Journal articles on the topic 'Polivinil alcool (PVA)'
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Escobar-Sierra, Diana Marcela, and Yuli Paola Perea-Mesa. "Manufacturing and evaluation of Chitosan, PVA and Aloe Vera hydrogels for skin applications." DYNA 84, no. 203 (October 1, 2017): 134–42. http://dx.doi.org/10.15446/dyna.v84n203.62742.
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El objetivo fue desarrollar membranas de Polivinil Alcohol (PVA) y Quitosano (Qo), capaces de absorber solución de Aloe Vera y luego liberarla gradualmente para acelerar la cicatrización de la herida. La metodología empleada consistió en variar la composición de las membranas usando quitosano y Polivinil Alcohol al 5 y 10% p/v, e implementar diferentes relaciones de PVA/Qo de 30/70, 50/50 y 70/30 (v/v), para posteriormente embeberlas en solución de Aloe Vera al 2% (v/v) y formar hidrogeles. Una vez obtenidos, éstos fueron caracterizados por Espectroscopía de Infrarrojo y Microscopía Electrónica de Barrido, y evaluadas por pruebas mecánicas, pruebas de absorción, y ensayos de actividad bactericida.El grado de entrecruzamiento entre el PVA y el Quitosano permitió obtener una matriz con alta capacidad de absorción y liberación controlada de Aloe Vera, con propiedades mecánicas y estabilidad dimensional aún después de rehidratadas. Las pruebas bactericidas mostraron actividad protectora del quitosano y del Aloe Vera, lo cual hace que este compuesto sea adecuado para aplicaciones que ayudan en la curación de heridas.
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Irawan, Maria Gracella, Henky Muljana, Asaf Kleopas Sugih, Usman Oemar, and Jessica Atin. "Sintesis polivinil alkohol tersulfonasi sebagai katalis dalam produksi metil ester: review." Jurnal Rekayasa Proses 16, no. 1 (July 21, 2022): 66. http://dx.doi.org/10.22146/jrekpros.70698.
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A B S T R A C TSulfonated polyvinyl alcohol (PVA) can be used as a heterogeneous catalyst in esterification or transesterification reactions during methyl ester production. This catalyst with PVA support has the potential to be used commercially like Amberlyst 46. However, there are several drawbacks in the conventional methods to produce sulfonated PVA compared to Amberlyst 46. In this paper, various processes of sulfonated PVA synthesis will be discussed including the advantages and disadvantages compared to Amberlyst 46. The synthesis of sulfonated PVA catalysts can be carried out using sulfosuccinate acid reagents or other acid reagents that have sulfonic groups that act as the active sites of the catalysts. The use of sulfosuccinate acid as the reagent produces catalysts with better catalytic activity, but the resulting product is not in granule form like Amberlyst 46 and can only be used continuously for seven times. The use of chlorosulfonic acid as the reagent resulted in granular catalysts. However, the catalyst has less catalytic activity and stability, and the reagent has a relatively high environmental impact. For the synthesis performed using sulfuric acid as the reagent, no result regarding catalytic activity has been reported elsewhere. The blending of the catalyst with other polymers resulted in improvements in the thermal stability and mechanical strength of the sulfonated polyvinyl alcohol. After a careful review of the procedures, we propose blending or double cross-linking processes combined with sulfonated PVA synthesis as a promising method to increase the thermal stability and mechanical strength of the catalysts. However, it is necessary to perform further laboratory validations on the catalytic activity of the catalysts produced from the combined method because blending may reduce the acid capacity of the catalyst.Keywords: esterification catalyst, polyvinyl alcohol, sulfonation A B S T R A KPolivinil alkohol (PVA) tersulfonasi dapat digunakan sebagai katalis heterogen dalam reaksi esterifikasi atau transesterifikasi dalam produksi metil ester. Katalis dengan support polivinil alkohol ini berpotensi untuk digunakan secara komersial seperti Amberlyst 46. Akan tetapi, PVA tersulfonasi yang disintesis secara konvensional masih memiliki banyak kekurangan dibandingkan dengan Amberlyst 46. Pada kajian ini akan dibahas mengenai berbagai alternatif proses sintesis PVA tersulfonasi termasuk kelebihan dan kekurangannya jika dibandingkan dengan Amberlyst 46. Sintesis katalis PVA tersulfonasi dapat dilakukan menggunakan reagen asam sulfosuksinat (SSA) maupun reagen asam lainnya yang memiliki gugus sulfonat yang berperan sebagai situs aktif katalis. Penggunaan reagen SSA menghasilkan katalis dengan aktivitas katalitik yang baik namun produk yang dihasilkan tidak berbentuk granula seperti Amberlyst 46 dan hanya dapat digunakan ulang sebanyak tujuh kali. Penggunaan reagen asam klorosulfonat dapat menghasilkan katalis berbentuk granula, namun memiliki aktivitas katalitik dan kestabilan kurang baik, serta reagen yang digunakan cukup berbahaya. Untuk proses sintesis menggunakan reagen asam sulfat belum ada hasil mengenai aktivitas katalitik, tetapi dengan adanya blending dengan polimer lain dapat memperbaiki kestabilan termal dan kekuatan mekanik PVA tersulfonasi yang dihasilkan. Proses blending atau double cross-linking yang digabung dengan sintesis PVA tersulfonasi dapat meningkatkan kestabilan termal dan kekuatan mekanik sehingga metode gabungan ini diyakini sebagai metode yang paling potensial dilakukan untuk menghasilkan PVA tersulfonasi dengan karakteristik terbaik. Meskipun demikian, perlu dilakukan penelitian lebih lanjut disertai tahapan pengujian aktivitas katalitik pada katalis yang dihasilkan dari metode gabungan karena kemungkinan proses blending dapat mengurangi kapasitas asam pada katalis.Kata kunci: katalis esterifikasi; polivinil alkohol; sulfonasi
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B Tou, Fathia Arami, Eti Indarti, and Ismail Sulaiman. "Pengaruh Penambahan Nanoselulosa dari Tandan Kosong Kelapa Sawit (Elaeis guinensis Jacq) terhadap Karakteristik Polivinil Alkohol (PVA)." Jurnal Ilmiah Mahasiswa Pertanian 5, no. 2 (May 1, 2020): 203–9. http://dx.doi.org/10.17969/jimfp.v5i2.14837.
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Abstrak: Tandan kosong kelapa sawit merupakan limbah padat terbesar yang dihasilkan oleh perkebunan kelapa sawit. Kandungan utama tandan kosong kelapa sawit adalah selulosa. Tingginya kandungan selulosa pada tandan kosong kelapa sawit dapat dimanfaatkan sebagai bahan dasar pembuatan nanoselulosa. Nanoselulosa merupakan selulosa yang dihasilkan dalam skala nano dan memiliki sifat karakteristik yang jauh lebih baik dibandingkan dengan selulosa. Pada penelitian ini dilakukan isolasi selulosa yang berasal dari tandan kosong kelapa sawit untuk menghasilkan nanoselulosa yang dapat dimanfaatkan sebagai pencampur (filler) pada polimer polivinil alkohol (PVA), sehingga diharapkan dapat memperbaiki karakteristik pada PVA. Tujuan dari penelitian ini yaitu untuk mengkaji isolasi selulosa menjadi nanoselulosa dari tandan kosong kelapa sawit serta mempelajari karakteristik pada PVA dengan adanya penambahan nanoselulosa. Penelitian ini dilakukan menggunakan rancangan penelitian deskriptif yang terdiri dari jumlah penambahan nanoselulosa (N) dan jumlah PVA (P). Karakterisasi yang dilakukan adalah uji ketebalan, uji kuat tarik, uji FT-IR, uji WVP, dan uji UV-Vis Spectrophotometer. Hasil dari penelitian menunjukkan bahwa penambahan nanoselulosa berpengaruh terhadap karakteristik film PVA. The Effects of Adding Nanocellulose From Oil Palm Empty Fruit Bunch (Elaeis guinensis Jacq) For Characterization of Polyvinil Alcohol (PVA) Abstract: Oil palm empty fruit bunches (OPEFB) are the largest solid waste produced by oil palm plantations. The main content of oil palm empty fruit bunches is cellulose. High cellulose content in oil palm empty fruit bunches can be used for making nanocellulose. Nanocellulose is cellulose that produced in nanoscale and it has better characteristic properties compared to cellulose. In this study, cellulose from oil palm empty fruit bunches was isolated to produce nanocellulose that can be used as filler for characterization of polyvinil alcohol (PVA). The purpose of this study is to examined the isolation of cellulose into nanocellulose from oil palm empty fruit bunches and to investiage the characteristics of PVA with the addition of nanocellulose. This study was conducted using a descriptive research design consisting of 2 (two) factors. The first factor was the total addition of nanocellulose (N) and the second factor was the amount of polyvinyl alcohol (P). The characterization that carried out were a thickness test, tensile strength, Fourier Transform Infra-Red (FT-IR), Water Vapor Permeability (WVP), and UV-Vis Spectrophotometer. The results of the study showed that the addition of nanocellulose can effect the characteristics of PVA films.
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Purwandari, Vivi, and Malemta Tarigan. "PREPARASI FILM NANOKOMPOSIT POLIVINIL ALKOHOL (PVA)/NANOKARBON DARI CANGKANG BUAH SAWIT (NCCS) DENGAN METODE PENCAMPURAN LARUTAN." JURNAL KIMIA SAINTEK DAN PENDIDIKAN 6, no. 1 (July 24, 2022): 11–16. http://dx.doi.org/10.51544/kimia.v6i1.2977.
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Polyvinyl alcohol (PVA) has good compatibility when added as filler in the form of nanocarbon so that it can produce environmentally friendly nanocomposite products. Thus, the addition of nanocomposites to PVA-based films is expected to increase and improve the mechanical properties of the resulting PVA films. This study aims to utilize palm fruit shells as raw materials for nanocarbons and as fillers for nanocomposites, as well as to determine the mechanical properties and thermal strength of nanocarbon nanofibers in the PVA matrix. Composite films were made using the solution mixing method. The research was conducted by mixing PVA solution (3.5 g) with various concentrations of nanocarbon from palm fruit shells (NCCS) and 2 ml of glycerol and 1 g of PEG 400. Film characterization includes tensile test, scanning differential calorimetry (DSC), and conductivity test. Tensile test of PVA/NCCS nanocomposite resulted in tensile strength of 0.314 MPa and an elongation of 4.21925 %. The thermal test of PVA/NCCS nanocomposite with DSC yielded a melting point of around 146.06oC. Electrical conductivity of PVA/NCCS 107.1 (1.07 x 10-3) s/cm. PVA/NCCS nanocomposite based on conductivity scale including a semiconductor material.
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Ayuni, Ni Putu Sri, Ni Wayan Yuningrat, and Ni Wayan Citra. "Kajian Transpor Kreatinin Menggunakan Membran Kitosan-Alginat Tertaut Silang Polivinil Alkohol (PVA)." Jurnal Rekayasa Proses 12, no. 2 (December 31, 2018): 56. http://dx.doi.org/10.22146/jrekpros.38401.
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A B S T R A C TThe objective of this research was to determine the efficiency of the creatinine transport using chitosan alginate cross linked by polyvinyl alcohol (PVA) 0.1% with 70, 100, and 130 mg/L of creatinine concentration. The subject of this study was the membranes of chitosan alginate PVA, while the object of this study was the efficiency of the creatinine transport. The PVA 0.1% cross-linking chitosan-alginate membrane (1:0.15) was successfully synthesized. The membrane synthesized was characterized by FTIR, as well as tensile and strain test. The FTIR spectra showed that there is a new peak of the amino group of chitosan and carboxyl group of alginate at ca. 1651 cm-1. The hydroxyl group appears at ca. 1088 cm-1 while ester groups at ca. 1088 cm-1 and ca. 1265 cm-1 which indicate the cross binding between alginate and PVA. The water uptake test of the chitosan alginate PVA membrane reaches 257.76% for 6 hours. The tensile test results of the membrane before and after creatinine transport are 2.77 MPa and 12.56 MPa while the strain tests yield 14.24% and 18.51%, respectively. The maximum efficiency of the creatinine transport using the chitosan-alginate cross linked by PVA is 51.02% at 130 mg/L creatinine. This creatinine transport result using the PVA cross linking chitosan-alginate membrane are more efficient than chitosan-pectin membrane (25.24%) with the same creatinine concentration.Keywords: chitosan-alginate PVA membrane; creatinine; cross-link; synthesis; transportA B S T R A KPenelitian ini bertujuan untuk menentukan nilai efisiensi transpor kreatinin menggunakan membran kitosan-alginat tertaut silang polivinil alkohol (PVA) 0,1% dengan konsentrasi kreatinin 70, 100 dan 130 mg/L. Subjek dalam penelitian ini adalah membran kitosan-alginat PVA, sedangkan objek penelitian ini adalah pengaruh efisiensi transpor pada variasi konsentrasi kreatinin. Membran kitosan alginat (1:0,15) tertaut silang PVA 0,1% telah berhasil disintesis. Karakterisasi membran kitosan-alginat tertaut silang PVA diperoleh untuk spektra FTIR membran menunjukkan bahwa telah terjadi pergeseran serapan gugus amino dari kitosan dan gugus karboksil dari alginat pada puncak sekitar 1651 cm-1. Pada bilangan gelombang 3363,86 cm-1 terdapat serapan gugus –OH serta pada bilangan gelombang sekitar 1088 cm-1 dan 1265 cm-1 berasal dari gugus ester yang menunjukkan ikatan silang antara alginat dan PVA. Hasil uji serapan air pada membran kitosan-alginat PVA selama 6 jam mencapai rata-rata 257,76%. Hasil uji tarik membran sebelum dan setelah transpor masing-masing: 2,77 MPa dan 12,56 MPa dan untuk hasil uji regang membran sebelum dan setelah transpor masing-masing: 14,24% dan 18,51%. Efisiensi transpor kreatinin pada membran kitosan-alginat tertaut silang PVA mencapai efisiensi transpor maksimal pada konsentrasi 130 mg/L (51,02%). Efisiensi transpor kreatinin ini lebih tinggi jika dibandingkan menggunakan membran kitosan-pektin (25,24%) pada konsentrasi yang sama.Kata kunci: kreatinin; membran kitosan-alginat PVA; sintesis; taut silang; transpor
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Rahmawati, Lia, Sadi Sadi, and Tri Wibawa. "Peningkatan Kualitas Kuat Tekan Produk Scaffold Hidroksiapatit (Ha)-Gelatin-Polivinil Alkohol (PVA) Menggunakan Metode Taguchi." Seminar Nasional Teknik dan Manajemen Industri 1, no. 1 (December 1, 2021): 32–38. http://dx.doi.org/10.28932/sentekmi2021.v1i1.40.
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Kerusakan tulang yang akan terjadi di Indonesia pada golongan tenaga kerja sebesar 67,76% berupa penurunan massa tulang dan sebesar 28,58% berupa gangguan kepadatan tulang. Scaffold dapat dijadikan sebagai alternatif dari perawatan penyembuhan kerusakan tulang dalam bentuk perancah berpori 3D. Scaffold dapat menyediakan lingkungan yang sesuai untuk regenerasi jaringan tulang. Biomaterial keramik sebagai bahan dasar yang cocok untuk scaffold karena karakteristiknya, namun memiliki kekurangan berupa elastisitas rendah dengan permukaan yang keras dan rapuh. Pada penelitian ini dilakukan penambahan material berupa biomaterial gelatin dan PVA yang mana sangat ideal untuk diferensiasi sel dan kekuatan mekanik dari scaffold. Dalam upaya memperbaiki kualitas produk dan proses pembuatan scaffold, desain eksperimen dengan Metode Taguchi untuk mengetahui parameter yang memberikan nilai kuat tekan yang sesuai dengan tulang manusia. Parameter proses yang digunakan yaitu rasio bubuk hydroxyapatite (HA), rasio bubuk gelatin, dan rasio bubuk polyvynyl alcohol (PVA). Berdasarkan hasil penelitian yang dilakukan parameter proses rasio bubuk hydroxyapatite (HA), rasio bubuk gelatin, dan rasio bubuk polyvynyl alcohol (PVA) sangat berpengaruh terhadap nilai kuat tekan scaffold. Hasil eksperimen konfirmasi diperoleh mean sebesar 3,287 MPa menunjukkan bahwa nilai kuat tekan scaffold berada pada rentan nilai kuat tekan manusia.
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Sultan, Asriana, Nur Ida, and Isriany Ismail. "Peningkatan Kadar Ketoprofen Terdisolusi melalui Pembentukan Dispersi Padat menggunakan Polivinil Alkohol (PVA)." Jurnal Farmasi Galenika (Galenika Journal of Pharmacy) (e-Journal) 5, no. 1 (March 28, 2019): 43–48. http://dx.doi.org/10.22487/j24428744.2019.v5.i1.12096.
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Ketoprofen is included in the Class II of Biopharmaceutical Classification System (BCS) which has low solubility. Low solubility will affect the dissolution rate and the dissolved concentration, so the absorption and bioavailability are low as well. Several studies have been conducted to improve the solubility and the dissolution of drugs from these group, such as by solid dispersion system. This study aims to determine the effect of polyvinyl alcohol (PVA) on the dissolved concentration of ketoprofen in solid dispersion and in physical mixture, and to decidethe optimum formula.Solid dispersion and physical mixture of ketoprofen - PVA were formulated with the ratio of 1:1, 1:2 and 1:4, and then compared with the standard ketoprofen. Evaluation of solid dispersion was performed by the intervention test of PVA as a matrix on the maximum wavelength of standard ketoprofen using a UV-Vis spectrophotometer and the dissolution test in artificial gastric fluid media without pepsin using a basket stirrer at pH ± 1,2, the temperature of 37 ± 0.5ºC, and device speed of 50 rpm. The sample was collected at 10, 20, 30, 45, and 60 minutes. The amount of dissolved ketoprofen was determined by a UV-Vis spectrophotometer at a wavelength of 260 nm. The results showed that there was no shifting on maximum wavelength point in both solid dispersions and physical mixtures. The dissolved ketoprofen concentration that was represented in solid dispersion was greater than in physical mixture and standard ketoprofen. The highest dissolved ketoprofen concentration was indicated in solid dispersion formula with the ratio of 1:1.
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Rahayu, Lale Budi Hutami, Ika Oktavia Wulandari, D. J. Djoko H. Santjojo, and Akhmad Sabarudin. "Effect of Stirring Speed on Characteristics of Fe3O4 Nanoparticles Coated with Polyvinyl Alcohol and Glutaldehyde as a Crosslinker." Natural B 4, no. 3 (April 1, 2018): 127–34. http://dx.doi.org/10.21776/ub.natural-b.2018.004.03.1.
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Treviño López, Eduardo Alfonso, Alberto Sandoval-Rangel, Adalberto Benavides Mendoza, Adalberto Benavides Mendoza, Hortensia Ortega Ortiz, Gregorio Cadenas Pliego, and Marcelino Cabrera de la Fuente. "Nanopartículas de selenio absorbidas en hidrogeles de quitosán-polivinil alcohol en la producción de pepino injertado." Revista Mexicana de Ciencias Agrícolas, no. 26 (July 7, 2021): 159–69. http://dx.doi.org/10.29312/remexca.v0i26.2946.
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En la búsqueda por mejorar el uso de los recursos naturales y aumentar el rendimiento y la calidad de los frutos empleando técnicas amigables con el medio ambiente, como el injerto y el uso de nanopartículas metálicas. El objetivo de este trabajo fue determinar el efecto del injerto combinado con la aplicación de diferentes concentraciones de nanopartículas de selenio (Se NPs) encapsuladas en un gramo del hidrogel de quitosán-polivinil alcohol (CS-PVA) en la productividad y producción de pepino injertado. Los tratamientos fueron aplicados al sustrato al momento del trasplante de la siguiente manera: 1, 2.5 y 5 mg de NPs de Se absorbidas en un gamo de hidrogeles de CS-PVA, CS-PVA sin NPs y un tratamiento control, en plantas de pepino con injerto y sin injerto. Las variables evaluadas fueron longitud y diámetro de tallo, peso fresco y seco de hojas, área foliar, longitud de raíz, longitud de fruto, número de frutos y rendimiento por planta. Los resultados mostraron que la aplicación de las NPs de Se tienen un efecto benéfico para las plantas, como un agente promotor del crecimiento y que junto con el injerto coadyuvan a obtener una mayor altura de la planta y peso de fruto obteniendo un mayor rendimiento por planta.
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Hamzah, Mohd Syahir Anwar, Nurul Amira Ab Razak, Celine Ng, Akmal Hafiszi Abdul Azize, Jumadi Abdul Sukor, Soon Chin Fhong, Mohd Safiee Idris, and Nadirul Hasraf Mat Nayan. "PREPARATION OF THE ELECTROSPUN POLYVINYLIDENE FLUORIDE / POLYVINYL ALCOHOL SCAFFOLD AS A POTENTIAL TISSUE REPLACEMENT." IIUM Engineering Journal 22, no. 1 (January 4, 2021): 245–58. http://dx.doi.org/10.31436/iiumej.v22i1.1548.
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: Polyvinylidene fluoride (PVDF), a piezoelectric material, is commonly used in tissue engineering due to its potential for mimicking the electrical microenvironment of biological conditions for tissue development. In this present research, polyvinyl alcohol (PVA) was introduced into electrospun PVDF fabrication through an electrospinning process, aiming to enhance the nanofibrous membrane's biocompatibility properties by improving the hydrophilicity properties to act as an artificial tissue scaffold. The electrospun PVDF/PVA membranes are found to be optimum at a PVDF-to-PVA ratio of 90:10 due to its excellent mechanical, morphological, and hydrophilicity conductivity properties. Fourier transform infrared (FTIR) spectroscopy verified strong hydrogen bonding interaction formed between the fluorine group of PVDF with oxygen-containing in the hydroxyl group of PVA. In-vitro cell culture showed that the enhanced hydrophilic property of electrospun PVDF/PVA could significantly enhance the cell growth. These positive results indicated that the scaffold could be implemented as artificial tissue material for tissue engineering applications. ABSTRAK: Polivinilidena fluorida (PVDF) adalah bahan piezoelektrik yang biasa digunakan dalam kejuruteraan tisu kerana potensinya menyerupai keadaan persekitaran mikro-elektrik biologi bagi perkembangan tisu. Dalam penyelidikan ini, polivinil alkohol (PVA) diperkenalkan ke dalam fabrikasi pintalan-elektro PVDF melalui proses pemintalan-elektro, yang bertujuan bagi mengembangkan sifat biokompatibiliti membran nanogentian dengan meningkatkan sifat hidrofilik bagi menjadi perancah tisu tiruan. Membran pintalan-elektro PVDF / PVA didapati optimum pada nisbah PVDF-ke-PVA, 90:10 kerana sifat kekonduksian, mekanikal, morfologi dan hidrofiliknya yang sangat baik. Spektroskopi transformasi inframerah Fourier (FTIR) mengesahkan interaksi ikatan hidrogen yang kuat terbentuk antara kumpulan fluoro PVDF dengan oksigen yang terkandung dalam kumpulan hidroksil PVA. Kultur sel secara in-vitro menunjukkan bahawa sifat hidrofilik pintalan-elektro PVDF / PVA dapat meningkatkan pertumbuhan sel secara signifikan. Hasil positif ini menunjukkan bahawa perancah ini dapat digunakan sebagai bahan tisu buatan bagi aplikasi kejuruteraan tisu.
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Arevalo, K., E. Aleman, G. Rojas, L. Morales, and L. J. Galan. "Properties and biodegradability of cast films based on agroindustrial residues, pectin and polivinilic alcohol (PVA)." New Biotechnology 25 (September 2009): S287—S288. http://dx.doi.org/10.1016/j.nbt.2009.06.651.
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Pamudji, Jessie S., Khairurrijal, Rachmat Mauludin, Titi Sudiati, and Maria Evita. "PVA-Ketoprofen Nanofibers Manufacturing Using Electrospinning Method for Dissolution Improvement of Ketoprofen." Materials Science Forum 737 (January 2013): 166–75. http://dx.doi.org/10.4028/www.scientific.net/msf.737.166.
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Background and purpose: Ketoprofen is an NSAIDs agent which has analgesic and anti inflammation effects. Ketoprofen is classified into class II in the biopharmaceutical classification system that has a high permeability but low solubility. Hence, the absorption rate of this substance is governed by its dissolution rate. Electrospinning is a method that combine solid dispersion technology and nanotechnology. This method can be selected to enhance the dissolution rate of active substances. The aim of this research is to improve the dissolution rate of ketoprofen through the preparation of polymeric nanofiber polivinyl alcohol (PVA) containing ketoprofen using electrospinning process. Methods: Preparation of nanofibers with various of PVA-ketoprofen ratio, flow rate, and PVA concentration in the solution were accomplished using electrospinning instrument. Casting solid dispersion film were also prepared by solvent evaporation method and used as a reference. The rates of dissolution of ketoprofen from each of nanofibers, casting films, and pure ketoprofen were conducted in HCl pH 1.2 medium at 37oC. Characterization of nanofibers was carried out using Scanning Electron Microscope (SEM) and X-ray Diffraction (XRD). Results: Nanofibers which contained of PVA-ketoprofen 1:1 in ratio w/w showed a significant improvement in dissolution (p<0.05) compared to the pure ketoprofen. Meanwhile, nanofibers obtained from a solution containing 7.5 % PVA (w/v) and 4 ml/h in flow rate showed the best dissolution rate improvement and significantly different (p<0.05) with either the casting film or the pure ketoprofen. The improvement of ketoprofen dissolution was due to the increasing of surface area of nanofiber and the change of ketoprofen from crystalline into amorphous form. Conclusion: Electrospinning technique can be used to improve the dissolution rate of ketoprofen through the PVA-ketoprofen nanofiber formation by choosing the appropriate polymer concentration and manufacturing process.
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Rahmadani, Dewi, Sumiati Side, and Suriati Eka Putri. "Pengaruh Penambahan PVA terhadap Ukuran Nanopartikel Perak Hasil Sintesis Menggunakan Bioreduktor Ekstrak Daun Sirsak (Annona muricata L.)." Sainsmat : Jurnal Ilmiah Ilmu Pengetahuan Alam 9, no. 1 (July 3, 2020): 1. http://dx.doi.org/10.35580/sainsmat91141862020.
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Penelitian ini bertujuan untuk menentukan pengaruh penambahan Polivinil Alkohol (PVA) terhadap ukuran nanopartikel perak hasil sintesis menggunakan bioreduktor ekstrak daun sirsak (Annona muricata L.). Nanopartikel perak dibuat melalui metode bioreduksi, larutan bioreduktor dicampur dengan prekursor AgNO3, tanpa penambahan PVA dan dengan penambahan PVA dengan variasi konsentrasi yang berbeda yaitu 1%; 1,5%; 2%; dan 2,5%. Berdasarkan hasil analisis gugus fungsi ekstrak daun sirsak menggunakan spektrofotometer FT-IR (Fourier Transform Infrared), menunjukkan serapan pada bilangan gelombang 3443 cm-1 yang menunjukkan adanya gugus –OH. Proses pembentukan nanopartikel perak dilihat dengan mengamati serapan UV-Vis. Hasil pengukuran menunjukkan bahwa nilai absorbansi meningkat dengan meningkatnya waktu kontak. Proses pembentukan nanopartikel diamati menggunakan Spektrofotometer UV-Vis melalui serapan UV-Vis. Hasil pengukuran serapan maksimun dari sampel hasil sintesis masing-masing konsentrasi menunjukkan λmax 503.0; 463.1; 436.0; 476.1; 503.1 nm selama dua hari dengan variasi konsentrasi PVA berturut-turut tanpa PVA 1%; 1,5%; 2%; dan 2,5%. Ukuran nanopartikel perak ditentukan menggunakan XRD (X-Ray Diffraction), distribusi rata-rata ukuran nanopartikel perak dengan tanpa penambahan PVA yaitu 30,80-50,25 nm dan kisaran ukuran terkecil nanopartikel perak yaitu 9,90-10,20 nm dengan penambahan PVA 1,5%. Berdasarkan penelitian yang telah dilakukan, maka dapat disimpulkan bahwa penambahan PVA mempengaruhi ukuran nanopartikel perak. Hal ini terjadi karena stabilisator berperan untuk mengontrol ukuran nanopartikel perak.Kata Kunci: Annona muricata Linn, PVA, reduksi, nanopartikel perak This study aims to determine the effect of adding Polyvinyl Alcohol (PVA) to the size of silver nanoparticle synthesized using bioreductor soursop leaf extract (Annona muricata L.). Silver nanoparticle made through method bioreduction, bioreductor solution was mixed with AgNO3 precursor, without addition of PVA and with the addition of PVA. That the variant of concentrations is 1%; 1.5%; 2%; and 2.5%. Based on the analysis of functional groups of soursop leaf extract using a spectrophotometer FT-IR (Fourier Transform Infrared), showed absorption at wave number 3443 cm-1 which indicate a -OH group.The process of formation of silver nanoparticles seen by UV-Vis absorption. The measurement results shows that the absorbance value increased with increasing contact time. The maximum absorbance measurement result of the samples synthesized each concentration showed λmax 503.0; 463.1; 436.0; 476.1; 503.1 nm for two days with various concentrations without PVA, 1%, 1.5%, 2%, and 2.5%. The size of silver nanoparticle were determined using XRD (X-Ray Diffraction), the average size distribution of silver nanoparticle without the addition of PVA is 30.80-50.25 nm and the smallest size range is 9.90-10.20 nm silver nanoparticle with addition PVA 1.5%. Based on research that has been done, it can concluded that addition of PVA have the effect to the size of silver nanoparticle. The stabilizer acts to control the size of silver nanoparticle.Keywords: Annona muricata Linn, PVA, reduction, silver nanoparticle.
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Haflin, Haflin, Agusriani Agusriani, Ruri Putri Mariska, and Barmi Hartesi. "Pengaruh Polimer Terhadap Kualitas Sabun Kertas Ekstrak Metanol Daun Sungkai (Peronema canescens Jack) Sebagai Antibakteri." Majalah Farmasetika 8, no. 2 (January 24, 2023): 175. http://dx.doi.org/10.24198/mfarmasetika.v8i2.43376.
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Penggunaan polimer pada sediaan sabun kertas sangat mempengaruhi bentuk sediaan dikarenakan sifat polimer memiliki volume rasio yang kecil sehingga sediaan yang dihasilkan menjadi elastis dan ringan. Polimer yang akan digunakan oleh peneliti yaitu polimer HPMC (Hydroxylpropyl methyl cellulose) dan PVA (Polivinil alcohol) dikarenakan polimer HPMC bersifat netral dan stabil dalam berbagai pH serta sediaan yang dihasilkan akan tampak jernih dan dapat membentuk film dengan baik [1] sedangkan polimer PVA dapat memudahkan difusi sediaan karena dapat terikat dengan air sehingga mudah diproses dalam pembuatan sediaan [2] maka hal tersebut menjadi pemicu bagi peneliti untuk melakukan uji pengaruh penggunaan polimer HPMC dan PVA terhadap kualitas sediaan sabun kertas dengan menggunakan zat aktif ekstrak metanol daun sungkai (Peronema canescens Jack) yang digunakan sebagai antibakteri. Penelitian ini bertujuan mengetahui pengaruh polimer HPMC dan PVA pada sediaan sabun kertas ekstrak metanol daun sungkai dan mengetahui aktivitas antibakteri sediaan sabun kertas ekstrak metanol daun sungkai menggunakan polimer yang berbeda. Formula sediaan diperoleh dari ekstraksi metanol daun sungkai dalam sediaan sabun kertas pencuci tangan antibakteri terhadap bakteri Staphylococcus aureus. Metode pengujian antibakteri menggunakan difusi cakram. Hasil penelitian menunjukkan sediaan yang baik yaitu pada sediaan F2B dengan formula sebagai berikut : Ekstrak daun sungkai (1%), HPMC (0,75%), Gliserin (1,25%), NaOH 50% (2,5%), Sodium lauryl sulfate (1,25%), Disodium EDTA (0.05%), Aquadestilata (ad 25) setiap masing-masing evaluasi seperti oganoleptis dengan hasil bentuk tipis elastis berbau khas sungkai dan berwarna hijau pekat, uji pH dengan hasil yang didapatkan yaitu 7,1, uji kestabilan busa dengan hasil yang didapatkan yaitu 94,2%, uji kadar asam lemak dan alkali bebas dengan hasil yang didapatkan yaitu 0,06%, dan uji kadar air mendapatkan hasil 15%. semua uji yang dilakukan telah memenuhi persyaratan uji menurut SNI. Hasil uji aktivitas antibakteri sabun kertas ekstrak metanol daun sungkai dengan konsentrasi 1% serta konsentrasi polimer HPMC 0,75% dapat menghambat bakteri Staphylococcus aureus dengan kategori zona hambat yang sedang yaitu persentase sebesar 5-10 mm.
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Abdillah, Hamid, Muhammad Baharits, Rijal Abidin, and Firdaus Rizki Biantoro. "Synthesis of Antimicrobial Silver Nanoparticle Varnish using Moringa Leaf Bioreductor (Moringa Olifiera)." Jurnal Kimia dan Rekayasa 2, no. 2 (January 21, 2022): 84–93. http://dx.doi.org/10.31001/jkireka.v2i2.38.
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Silver nanoparticles have stable properties and potential applications especially as anti-microbial agents. The growth of fungi and bacteria on the wood surface can be inhibited by varnishing with silver nanoparticles. The nano-silver particles were prepared by synthesizing silver nitrate at concentration of 1, 3, and 5 mM with Moringa oleifera as a bioreductant. PVA (Polyvinyl Alcohol) as a stabilizer was varied at the levels of 0.5%, 1%, and 2%. In the UV-Vis test, the wave peaks are in the range 395-515 nm, this is in accordance with the characteristics of silver nanoparticles. The addition of 1% PVA to silver nanoparticles provided the best stability among the four concentrations provided by evidence of low maximum wavelength shift after storing. Particle size examination using the Particle Size Analyzer (PSA) showed silver nanoparticles had a size of 75.6 nm. Then the silver nanoparticle solution was applied to the resin varnish. The solution of silver nanoparticles has an effect on the antimicrobial properties of resin varnish, as evidenced by the absence of mold growth in the media with silver nanoparticles added. Abstrak Nanopartikel perak memiliki sifat yang stabil dan aplikasi yang potensial khususnya sebagai agen anti-mikroba. Pertumbuhan jamur dan bakteri pada permukaan kayu dapat dihambat dengan pernis yang diberi bahan nanopartikel perak. Partikel nano-perak dibuat melalui sintesis perak nitrat konsentrasi 1, 3, dan 5 mM dengan bioreduktor daun kelor (Moringa oleifera). PVA (Polivinil Alkohol) sebagai stabilsator divariasikan pada kadar 0,5, 1, dan 2%. Pada pengujian UV-Vis, puncak gelombang berada pada rentang 395-515 nm yang sesuai dengan karakteristik nanopartikel perak. Penambahan PVA 1% pada nanopartikel perak memberikan kestabilan paling baik diantara keempat konsentrasi karena pergeseran panjang gelombang maksimal yang rendah. Pemeriksaan ukuran partikel menggunakan Partikel Size Analyzer ( PSA ) menunjukkan nanopartikel perak memiliki ukuran 75,6 nm. Selanjutnya larutan nanopartikel perak tersebut diaplikasikan pada pernis damar. Larutan nanopartikel perak berpengaruh terhadap sifat anti mikroba pada pernis damar, dibuktikan dengan tidak tumbuhnya jamur pada media yang ditambahkan nanopartikel perak.
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Suhendar, Haris, Ahmad Kusumaatmaja, Kuwat Triyana, and Iman Santoso. "Effect of Chemical Reduction Temperature on Optical Properties of Reduced Graphene Oxide (rGO) and its Potentials Supercapacitor Device." Materials Science Forum 901 (July 2017): 55–61. http://dx.doi.org/10.4028/www.scientific.net/msf.901.55.
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Reduced graphene oxide (rGO) has been successfully synthesized from graphite powder using Hummer’s Method. The epoxy group in GO structure was reduced by hydrazine 80 wt% at a temperature of 70o, 80o, and 90°C. The optical properties of produced rGO were characterized by using Uv-Vis and FTIR spectrometer. From Uv-Vis spectroscopy we observe that the absorbance of rGO decreased as increasing the reduction temperature. This is because the higher reduction temperature yields a high degree of rGO defect. The rGO produced at a reduction temperature of 70oC has very close similiraties absorbance spectrum with rGO produced by Sigma Aldrich Company. The Uv-Vis absorbance of rGO was used to calculated optical constant, and by using Kramers-Kronig relation we got refractive index values of rGO. The decreasing of absorbance may also stem out from the reducing of C=C bonding with sp2 hybridization due to the presence of energetic Hydrazine as indicated by the decrease of FTIR spectrum at ~1600 cm-1. Our produced rGO then used to fabricated the supercapacitor device with a mass of 0,03 gram using Polivinyl Alcohol (PVA) as a binder. From cyclic voltammetry measurement, we obtain the specific capacitance of our rGO-based supercapacitor is 2.45 F which is still in the category of supercapacitive although the optimization of rGO and PVA composition is still required. Our result shows the exciting potential of rGO based supercapacitor as electrical energy storage.
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Velásquez-Penagos, José, Sonia Gutiérrez-Parrado, and Diana Barajas-Pardo. "Evaluación de diferentes medios de cultivo en la producción in vitro de embriones bovinos." Ciencias Veterinarias 36, no. 3 (December 31, 2018): 32. http://dx.doi.org/10.15359/rcv.36-3.22.
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La producción de embriones in vitro de bovinos es una biotecnología que se viene adelantando yconsolidando como una práctica cada vez mayor para la mejora de nuestras ganaderías; sin embargo,una de las preocupaciones es sobre el tema de medios y su eficiencia, en este sentido el propósito delestudio se enmarcó en probar cuatro protocolos diferenciales en las fases de maduración oocitaria(MO) y desarrollo embrionario (DE): 1. MO-(LH-Hormona Luteinizante + FSH-Hormona folículoestimulante + EGF-factor de crecimiento epidermal + IGF-factor de crecimiento insulinico + ITSinsulinatransferrenina y selenio + SFB10 %-suero fetal bovino al 10 %), DE-(SOF-fluido oviductalsintético + SFB10 %); 2.MO-(LH + FSH + EGF + IGF + ITS + SFB5 %), DE-(SOF + BSA-albumina séricabovina + ITS); 3. MO-(LH + FSH + EGF + IGF + ITS + PVA-polivinil alcohol), DE-(SOF + PVA); 4.MO-(LH + FSH + SFB10 %), DE-(SOF + SFB5 %). Las variables consideradas para los 4 protocolos fueron:1) maduración de ovocitos, 2) división a las 48 horas de fecundación y 3) producción de blastocitos.El estudio se apoyó en estadística descriptiva análisis de varianza, pruebas de Chi2. Los resultadosobtenidos nos indican un comportamiento similar en las tasas de maduración de oocitos (p>0.05) paralos protocolos 1 (78.3 %), 2 (85.00 %), 3 (85.00 %) y diferente (p<0.05) para el protocolo 4 (70.36 %). Paralas tasas de división a las 48 horas se observan mayores valores (p<0.05) para los protocolos 1 (71.15%) y 4 (71.94 %) que guardan similitud con respecto al 2 (50.20 %) y 3 (55.88 %) que igualmente sonsimilares (p>0.05). Podemos concluir que las mejores tasas de blastocitos se obtuvieron en el protocolo1 (50.82 %) en forma significativa (p<0.05) seguido del 4, 2, y 3. En términos integrales el estudiorealizado brinda las posibilidades de cuatro protocolos para la producción de embriones.
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Rafaela Mendes Santos Pereira, Fernanda Sana Pertrini, Rodrigo Fernandes Castanha, Vera Lucia S. S. De Castro, and Claudio Martin Jonsson. "Efeito da nanoprata no crescimento e teor de clorofila da macrófita aquática Lemna minor." STUDIES IN ENVIRONMENTAL AND ANIMAL SCIENCES 2, no. 3 (December 20, 2021): 70–80. http://dx.doi.org/10.54020/seasv2n3-005.
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As nanopartículas de prata (AgNP) vêm despertando grande interesse no meio científico por possuírem propriedades importantes, tais como, condutividade elétrica e térmica, atividade catalítica, flexibilidade, estabilidade química, maleabilidade e o baixo custo de produção. Apesar do desempenho em diferentes função, estudos têm alertados sobre os possíveis efeitos que a AgNP pode causar ao meio ambiente decorrente do aumento de sua produção e utilização. A Lemna minor (Lentilha-de-água) é uma macrófita encontrada em água doce e normalmente utilizada em testes de ecotoxicidade de poluentes ambientais. Este estudo teve como objetivo avaliar os efeitos da AgNP estabilizada em polivinil álcool (PVA) sobre o crescimento, teor de clorofila e massa da matéria úmida da macrófita. As mudas foram expostas em 5 mL de solução teste, com 24 repetições para cada concentração-teste: 0,0; 0,01; 0,1; 1; 10 e 100 mg L-1 de AgNP-PVA. Foi contabilizado diariamente o número de frondes, e ao final do período de exposição de 7 dias foi determinada a concentração efetiva média a 168 horas (CE50-168h) para cada indicador avaliado. A concentração de efeito não observado (CENO) associada à taxa de crescimento, teor de clorofila e peso úmido é respectivamente de 0,326; 0,370 e 0,261 mg L-1. Os resultados deste estudo em conjunto com o de outros organismos servem como parâmetros de ecotoxicidade para estabelecimento de concentração máximas de proteção das comunidades. Silver nanoparticles (AgNP) have attracted great interest in the scientific community because they have important properties, such as eletrical and thermal conductivity, catalytic activity, flxibility, chemical stability, malleabillity and low production cost. Despite the performace in different functions, studies have warned about the possible effects that AgNP can cause to the environment due to its increased production and use. Lemna minor (Duckweed) is a macrophyte found in fresh water and commonly used in ecotoxicity tests for environmental pollutants. This study aimed to evaluate the effects of AgNP stabilized in polynivyl alcohol (PVA) on macrophyte growth, chlorophyll content and wet matter mass. The seedlings were exposed to 5 mL of test solution, with 24 repetitions for each test concentration: 0.0; 0.01; 0.1; 1; 10 and 100 mg L-1 AgNP-PVA. The number of fronds was counted daily and the mean effective concentration at 168 hours (EC50-168 h) was evaluated for each end point at the end of the 7-day exposure period. The no observed effect concentration (CENO) related with the growth rate, chlorophyll content and wet weight is respectively of 0.326; 0.370 and 0.261 mg L-1. The results of this study serve as ecotoxicity parameters in conjunction with the parameters of other organisms in order to establish maximum concentrations for protection of the communities.
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Ayunata, Yudi, Laili Fitria, and Ulli Kadaria. "Pengolahan Air Gambut dengan Media Filter Keramik Berpori (Peat Water Treatment Using Portable Ceramic Filter Media)." Jurnal Teknologi Lingkungan Lahan Basah 8, no. 2 (November 12, 2020): 049. http://dx.doi.org/10.26418/jtllb.v8i2.43030.
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AbstractAreas characteristic of the soil peaty usually contains brown water, PH (3-5), humus acid, organic substances, and high iron. In this research samples of raw water from the river agreed II which has a pH of 5.67, organic substances 232.17 mg/L, color is 1,346 PT-CO, and Iron Metal (Fe) is 0.96 mg/L. Quality of the parameter is not qualified (PERMESKES No 32 the year 2017) hygiene sanitation and clean water. This study knows the effectiveness of porous ceramic filters with a mixture of eggshells, zeolite, and polyvinyl alcohol (PVA) in sintering at 220 oC for 6 hours. Mixed variation of eggshell, zeolite, and PVA made is type (I) 67.5%: 22.5%: 10%, type (II) 45%: 45%: 10%, and type (II) 22.5%: 67,5%: 10%. Results showed a porous ceramic filter with a mixture of eggshells, zeolite, and PVA for each type filter (I), type (II), and type (III) have the density of 2, 092gr/CM3, 2, 080gr/CM3, 2, 006gr/Cm3. Porosity of 18%, 43%, and 69% as well as flux 1305 L/m2. Jam, 1813 L/m2. Clock, and 2209 L/m2. Jam. The highest color loss effectiveness in type Filter (II) 40% from 1001 TCU to 592.5 TCU. The type (I) effectiveness increases peat water pH from 5.67 to 6.84 by 17%. The highest efficacy organic substances Parameter type (II) amounted to 77% from 232.17 mg/L to 51.64 mg/L. turbidity of highest efficacy type (III) 48% of 29.6 mg/L to 15.35 mg/L. Iron Parameters Highest efficacy type (III) amounted to 53.12% from 0.96 mg/L to 0.45 mg/L and the highest effectiveness parameters of the type (III) of 78% from 139.44 mg/L to 59.91 mg/L. Keywords: peat water, eggshells, ceramic filters, zeolite Abstrak Daerah karakteristik tanah bergambut biasanya mengandung air berwarna coklat, pH (3-5), berkadar asam humus, zat organik,dan besi yang tinggi. Dalam penelitian ini sampel air baku dari sungai Sepakat II yang memiliki pH 5,67, zat organik 232,17 mg/L, warna adalah 1.346 pt-co, dan logam besi (Fe) adalah 0,96 mg/L. Kualitas parameter tersebut tidak memenuhi syarat (PERMESKES No 32 Tahun 2017) higiene sanitasi dan air bersih. Penelitian ini mengetahui efektivitas filter keramik berpori dengan campuran media cangkang telur, zeolit, dan Polivinil Alkohol (PVA) yang disintering dengan suhu 220 oC selama 6 jam. Variasi campuran bahan cangkang telur, zeolit, dan PVA yang dibuat adalah Tipe (I) 67,5 % : 22,5 % : 10%, Tipe (II) 45%:45% : 10%, dan Tipe (II) 22,5% : 67,5%:10%. Hasil menunjukan filter keramik berpori dengan campuran cangkang telur, zeolit, dan PVA untuk setiap filter Tipe (I), Tipe (II), dan Tipe (III) yaitu memiliki densitas sebesar 2,092gr/Cm3, 2,080gr/Cm3, 2,006gr/Cm3. Porositas sebesar 18%, 43%, dan 69% serta Fluks 1305 L/m2.jam, 1813 L/m2.jam, dan 2209 L/m2.jam. Penurunan warna efektivitas tertinggi pada filter Tipe (II) 40% dari 1001 TCU menjadi 592,5 TCU. Tipe (I) efektivitas meningkatkan pH air gambut dari 5,67 menjadi 6,84 sebesar 17%. Parameter zat organik efektivitas tertinggi Tipe (II) sebesar 77% dari 232,17 mg/L menjadi 51,64 mg/L. Kekeruhan efektivitas tertinggi Tipe (III) 48% dari 29,6 mg/L menjadi 15,35 mg/L. Parameter besi efektivitas tertinggi Tipe (III) sebesar 53,12 % dari 0,96 mg/L menjadi 0,45 mg/L dan parameter kesadahan efektivitas tertinggi Tipe (III) sebesar 78% dari 139,44 mg/L menjadi 59,91 mg/L. Kata Kunci: peat water, eggshells, ceramic filters, zeolite
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Etikaningrum, Nfn, Joko Hermanianto, Evi Savitri Iriani, Rizal Syarief, and Asep Wawan Permana. "PENGARUH PENAMBAHAN BERBAGAI MODIFIKASI SERAT TANDAN KOSONG SAWIT PADA SIFAT FUNGSIONAL BIODEGRADABLE FOAM." Jurnal Penelitian Pascapanen Pertanian 13, no. 3 (February 2, 2018): 146. http://dx.doi.org/10.21082/jpasca.v13n3.2016.146-155.
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<p>Pengembangan <em>biofoam</em> sebagai alternatif pengganti styrofoam telah banyak dilakukan. Bahan utama dalam pembuatan <em>biofoam</em> adalah pati murni, namun biofoam yang dihasilkan masih bersifat rapuh dan mudah menyerap air. Oleh karena itu adonan <em>biofoam</em> perlu ditambahkan bahan lain diantaranya <em>plasticizer</em>, pati modifikasi, polimer sintetis dan serat. Salah satu serat alam yang cukup potensial yaitu tandan kosong sawit (TKS). Tujuan penelitian ini adalah untuk mengetahui pengaruh pembuatan <em>biofoam</em> dari serat yang dimodifikasi dengan beberapa metode yang berbeda serta dengan konsentrasi yang berbeda sehingga dapat menghasilkan <em>biofoam</em> dengan karakteristik terbaik. Proses pembuatan biofoam dilakukan menggunakan teknik <em>thermopressing</em> dengan mencampurkan tapioka, <em>Polivinil alcohol</em> (PVA) dan dan jenis modifikasi STKS (selulosa tandan kosong sawit), NSTKS (nanoselulosa tandan kosong sawit) dan SATKS (selulosa asetat tandan kosong sawit) dengan konsentrasi serat (1%, 3% dan 5%). Karakterisasi <em>biofoam</em> meliputi daya serap air, kuat tekan, densitas, kristalinitas, titik leleh (Tm) dan morfologi. Jenis modifikasi NSTKS dan SATKS pada konsentrasi tinggi menghasilkan nilai daya serap air tinggi, kuat tekan rendah dan densitas rendah. Hasil penelitian menunjukkan bahwa STKS 5% dapat menurunkan daya serap air, meningkatkan densitas dan kuat tekan.</p><p align="center"><strong>English Version Abstract</strong></p><p align="center"><strong><strong>Effect of Addition Various Modification Empty Fruit Bunches Fiber on Functional Properties of Biodegradable Foam</strong></strong></p><p>Biodegradable foam as alternative to styrofoam has been developed with pure starch as the main ingredient, but biofoam produced is still fragile and easyly absorbs water. Therefore, other materials such as plasticizer, modified starch, synthetic polymers and fiber need to be added into dough formulation. One of the natural fibers of considerable potential is oil palm empty fruit bunches (EFB). The purpose of this study was determine the effect of incorporation of different concentration of fibers modified with several different methods on the biofoam characteristics. Biofoam was prepared by mixing tapioca, polyvinyl alcohol (PVA), and various modification of EFB, namely STKS (empty fruit bunches cellulose), NSTKS (empty fruit bunches nanocellulose) and SATKS (empty fruit bunches cellulose acetate) by thermopressing technique. Each type of cellulose was added in three different concentrartion (1%, 3%, and 5%). Biofoam characterization included water absorbtion capacity, compressive strength, density, crystalinity, melting point (Tm) and morphology. Biofoam made from NSTKS and SATKS with high concentration have high water absorb capacity, low compressive strenght and density. The results showed that the addition of STKS at a concentration of 5% decreased water absorbtion capacity and, increased density and compressive strength.</p>
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Mohd Rusdi, Muhamad Khairul Nizam, Afiq Arif Aminuddin Jafry, Nur Farhanah Zulkifli, Farina Saffa Mohamad Samsamnun, Mohamad Badrol Hisyam Mahyuddin, SULAIMAN WADI HARUN, Mohd Shahnan Zainal Abidin, and Norazlina Saidin. "PASSIVELY Q-SWITCHED YTTERBIUM-DOPED FIBER LASER EMPLOYING SAMARIUM OXIDE AS SATURABLE ABSORBER." IIUM Engineering Journal 22, no. 1 (January 4, 2021): 58–67. http://dx.doi.org/10.31436/iiumej.v22i1.1396.
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The rapid developments in transition metal dichalcogenide materials as a saturable absorber (SAs) have been demonstrated to be an effective method for generating Q-switched fiber laser. This work, reports on the generation of Q-switched fiber laser in the 1-micron region using samarium oxide (Sm2O3) saturable absorber (SA). The Sm2O3 thin film SA was fabricated in- The rapid developments in transition metal dichalcogenide materials as saturable absorbers (SAs) have been reported to be efficient materials for generating Q?switched fiber lasers. In this paper, we report on the use of samarium oxide (Sm2O3) saturable absorber (SA) for 1-micron Q-switched fiber laser generation. The Sm2O3 thin film SA was constructed in-house through which the Sm2O3 powder was mixed and stirred in polyvinyl alcohol (PVA) solution. It was then integrated into the ytterbium-doped fiber laser (YDFL) ring cavity, hence producing a sequence of Q-switched pulsed lasers at 1062.49 nm wavelength. The stable pulse train appeared from 69.97 to 111.1 kHz between the applied pump power of 57 mW to 96 mW. The signal-to-noise ratio (SNR) of 38.56 dB was recorded at the 57 mW pump power, whereas the pulse energy raised until 15.21 nJ at 96 mW. These results showed that the Sm2O3 could be a favourable SA material to iniatiate Q-switched ytterbium-doped pulsed fiber laser. ABSTRAK: Perkembangan pesat dalam bahan logam peralihan dichalcogenide sebagai bahan penyerap boleh larut (SAs) telah dilaporkan sebagai kaedah yang berkesan bagi menjana laser fiber Q-switched. Kajian ini menggunakan samarium oksida (Sm2O3) saturable absorber (SA) bagi menjana laser gentian Q-switched 1-Micron. Filem nipis Sm2O3 SA telah dihasilkan melalui campuran serbuk Sm2O3 ke dalam cecair polivinil alkohol (PVA) dalam persekitaran makmal. Kemudian, ia diintegrasi ke dalam rongga gelang laser gentian dop-ytterbium (YDFL), lalu menghasilkan denyut laser Q-switched stabil pada jarak gelombang 1062.49 nm. Denyutan stabil muncul dari 69.97 kepada 111.1 kHz pada kuasa pam yang dikenakan antara 57 mW hingga 96 mW. Nisbah isyarat-hinggar (SNR) pada 38.56 dB telah direkodkan pada pam kuasa 57 mW, sementara denyut tenaga ditingkatkan kepada 15.21 nJ pada 96 mW. Keputusan menunjukkan Sm2O3 merupakan bahan SA penggalak yang memuaskan bagi menjana denyut laser gentian dop-ytterbium Q-switched. house. It was integrated into the ytterbium-doped fiber laser (YDFL) ring cavity, hence producing a stable passively Q-switched laser operating at 1062.49 nm wavelength. Stable pulse train appeared from 69.97 to 111.1 kHz at the tunable pump power of 57 mW to 96 mW. The pulse energy of up to 15.21 nJ and signal-to-noise ratio (SNR) of 38.56 dB for the fundamental frequency were recorded. The results showed that the Sm2O3 could be a favourable SA material for the broadband generation of Q-switched fiber laser.
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Chabala, Luisa Fernanda Gomez, Martha Elena Londoño Lopez, and Claudia Elena Echeverri Cuartas. "Caracterización de matrices de Polivinil alcohol-Alginato-Quitosano-Aloe vera." Revista Ingeniería Biomédica 12, no. 23 (December 10, 2018). http://dx.doi.org/10.24050/19099762.n23.2018.806.
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El objetivo de este trabajo fue obtener un sistema que pueda ser usado para conservar de manera localizada en una herida dérmica las propiedades cicatrizantes y refrescantes del Aloe Vera usado en la medicina tradicional, integrando dicho principio activo en una matriz polimérica compuesta por alginato, quitosano y alcohol polivinílico (PVA), los cuales en conjunto poseen propiedades de resistencia mecánica, biodegradabilildad y biocompatibilidad, necesarios para este tipo de aplicación. Para llevar a cabo esta investigación, se evaluó la morfología, grupos funcionales, propiedades mecánicas y cinética de liberación de las muestras. Cada una de las matrices evidenciaron una morfología con poros interconectados y estabilidad mecánica. La liberación de Aloe vera desde la matriz de PVA-alginato-quitosano tuvo un comportamiento no fickiano, mientras la de alginato-quitosano siguió un comportamiento más cercano al fickiano. Las matrices de PVA-quitosano-alginato y alginato- quitosano por sus características, mecánicas, morfológicas de poros definidos e interconectados, y de cinética de liberación representan buenos modelos para ser tenidos en cuenta como sistemas de liberación controlada de medicamentos.
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Abd. Aziz, Azila. "Quantitative Analysis Of Performance Of A Hydrogen Peroxide–Based Glucose Biosensor." Jurnal Teknologi, January 20, 2012. http://dx.doi.org/10.11113/jt.v51.149.
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Satu biosensor glukosa separa telah dibina menggunakan satu lapisan dalaman yang selektif, satu lapisan enzim dan satu elektrod emas. Kedua–dua lapisan membran tersebut adalah berasaskan polivinil alcohol (PVA) tersambung silang. Prestasi biosensor glukosa tersebut telah dinilai terutamanya prestasi terhadap gangguan asetaminofen, yang merupakan molekul tak ionik. Sensitiviti enzim tersekat gerak tersebut terhadap glukosa adalah tinggi tetapi ianya tidak mencukupi untuk melawan gangguan asetaminofen. Kehadiran lapisan dalaman PVA yang hanya sederhana selektif tidak menyebabkan kesan yang ketara pada gangguan. Satu model matematik kemudiannya digunakan untuk menganalisis prestasi biosensor yang lengkap. Satu lapisan luar ditambah secara simulasi kepada dua lapisan terdahulu. Model matematik tersebut meramalkan bahawa penambahan satu lapisan luar yang mempunyai kebolehtelapan yang rendah terhadap bahan larut mampu memperbaiki prestasi sensor. Kata kunci: Biosensor glukosa; model matematik; asetaminofen; gangguan elektrokimia; polivinil alkohol tersambung silang A partial glucose biosensor was constructed using a selective internal layer, an enzyme layer and a gold electrode. Both membrane layers are based on cross–linked polyvinyl alcohol (PVA). The performance of the partial glucose biosensor was analyzed particularly with respect to the interfering effects of acetaminophen, a non–ionic molecule. The sensitivity of the immobilized enzyme to glucose was high but it was not high enough to counter acetaminophen interference. The addition of the moderately selective PVA internal layer did not seem to have a significant effect on interference. A mathematical model was then used to analyze the performance of a completed biosensor. A simulated external layer was added to the two layers. The mathematical model predicted that the addition of an external layer with lowered permeability to solutes could improve the performance of the sensor. Key words: Glucose biosensor; mathematical modeling; acetaminophen; electrochemical interference; cross-linked polyvinyl alcohol
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Alva Edy Tontowi, M. Taha Ma’ruf, Widowati Siswomihardjo, Marsetyawan HNE. "UJI BIOKOMPATIBILITAS KOMPOSIT POLIVINIL ALKOHOLHIDROKSIAPATIT DENGAN PENGUAT CATGUT SEBAGAI BAHAN PENYAMBUNG PATAH TULANG." Jurnal Teknosains 3, no. 1 (December 22, 2013). http://dx.doi.org/10.22146/teknosains.6128.
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Bone fracture fixation devices have been using rigid metallic materials such as titanium, titanium-alloy or cobalt chrome. Besides having some advantages, the titanium fixation devices also have disadvantages, such as too high strength and stiffness. This continuously stimulates the bone, causing bone atrophy under the plate, further disrupting the growth of bones, especially in children. Other deficiencies of this metal material is its sensitivity to temperature changes and the spread of metal ions in several organs. Some of these shortcomings led to the need for a secondary operation. Bone fracture fixation devices, such as the poly-l-lactic acid (PLLA), can be absorbed by the body and show some other advantages. However, it also has some drawbacks due to the high crystalline products during the degradation process. Lactic acid monomer released after degradation causes cellular response at the implant site, which facilitates the release of chemical mediators, such as prostaglandine by fibroblasts and macrophages as a cause of bone resorption. Therefore, this study aimed to develop the use of other polymeric materials that have good biocompatibility,appropriate mechanical strength, and can be absorbed by the body, such as Polyvinyl Alcohol (PVA). Previous research suggests that the PVA-HA composite with catgut reinforcement has sufficient and stable mechanical strength to be used as bone fracture fixation material. The purpose of this study is to know whether the PVA-HA composite with catgut reinforcement has good biocompatibility without toxicity and hypersensitivity effects in experimental animals. Biocompatibility testing includes local cytotoxicity and type IV contact hypersensitivity test. This type of research is experimental in vivo laboratory using wistar rats (Rattus norvegicus). Testing is done through two phases, in which induction or sensitization phase is done by rubbing PVA-HA composite with catgut reinforced ointment powder on the ears that lasts up to 10 days. After being rested for 3 days, this is followed by a second phase contact (elicitation) on day 14 and observed in the period of 24, 48, and 72 hours. Observations were made macroscopically and ear thickness was measured with a micrometer. Local toxicity testing is done by implantation of PVA-HA composite with catgut reinforcement on the back catgut of wistar rats. After a certain time period, the implant material is opened,examined, and observed histologically under a light microscope. The results showed no discoloration or induration on the animal ears in all treatment and control groups, both for the sensitization and the elicitation phase. One way ANOVA statistical test showed that there were no significant differences in the results of measurements of the thickness of the wistar rats ears from all treatment groups before and after treatment on measures 24, 48 and 72 hours (ρ >0.05). Microscopic examination showed no infiltration of acute inflammatory cells such as neutrophils, basophils or eusinofil, and chronic inflammatory cell infiltration such as macrophages, lymphocytes and plasma cells. It can be concluded that the PVA-HA composite with catgut reinforcement is a material that does not cause toxicity and hypersensitivity in experimental animals, thus potentially can be used as bone fractures fixation material.
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Uce Lestari, Yokhobet Ade Jesika, and Muhaimin. "Formulasi Masker Gel Peel Off Arang Aktif Dari Cangkang Kelapa Sawit(Eleis Quinemis Jacq) Sebagai Pembersih Wajah Dengan Basis Polivinil Alkohol (Pva)." Talenta Conference Series: Science and Technology (ST) 2, no. 2 (June 30, 2019). http://dx.doi.org/10.32734/st.v2i2.505.
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Cangkang kelapa sawit adalah salah satu limbah yang dapat diolah menjadi arang aktif. Arang aktif adalah karbon yang telah diaktivasi sehingga karbon memiliki pori-pori dan area permukaan yang besar guna meningkatkan daya serap kotoran pada wajah sebagai pembersih wajah. Tujuan dari penelitian ini adalah mencari alternative aplikasi limbah cangkang kelapa sawit guna memberikan nilai tambah, arang aktif dapat dimanfaatkan sebagai masker pembersih wajah dalam bentuk gel peel off. Untuk membuat masker gel untuk kulit dapat menggunakan Polyvinyl Alcohol (PVA). PVA digunakan karena dapat membentuk lapisan elastis dan kuat ketika kontakdengankulit dan mudah mongering tanpa perlu adanya bahan aditif. Masker gel peel off arang aktif diuji stabilitas fisiknya. Evaluasi sifat fisik yang dilakukan adalah pemeriksaan organoleptik, pemeriksaan homogenitas, pemeriksaan pH, viskositas dan reologi, uji sebaran, uji waktu kering, uji iritasi, uji kesukaan, dan uji kondisional. Hasil penelitian menunjukkan bahwa formula ke-3 memiliki sifat fisik paling ideal dan lebih disukai oleh panelis. Efektivitas masker PVA-arang aktif diamati dengan menggunakan kamera digital yang menunjukkan struktur permukaan kulit lebih halus dan bersih setelah masker diaplikasikan dibandingkan dengan kulit yang tidak menggunakan masker.
Palm shell is one of the waste that can be processed into activated charcoal. Activated charcoal is a carbon that has been treated by activation so that the compound has pores and a very large surface area in order to increase the absorber power to the dirt on the face as a facial cleanser. The purpose of this research is to look for alternative utilization of waste into activated charcoal that can provide added value so it can be formed into a face cleansing mask in the form of peel off gel. To create gel masks made of skin containing such as Polyvinyl Alcohol (PVA). PVA is used because PVA will form an elastic and strong peel off coating to get in contact with the skin well and easily dry out without the help of other materials. Gel mask exfoliated activated charcoal tested its physical stability. Evaluation of physical properties performed is organoleptic examination, homogeneity examination, pH examination, viscosity and rheology, spreading test, dry time test, favorite test irritation test, and test conditional test. The results showed that the 3rd formula has the most ideal physical properties and preffered more by panelists, which then tested the effectiveness in the dirt net. The effectiveness is using a digital camera shows the structure of skin surfaces are smoother and cleaner after the mask was being applied compare to those skin where no mask applied.