scholarly journals Ekstraksi Glukomanan dari Umbi Gembili (Dioscorea esculenta L.)

KOVALEN ◽  
2021 ◽  
Vol 7 (1) ◽  
pp. 51-58
Author(s):  
Pratiwi Listyana Sareu ◽  
Nurhaeni ◽  
Ahmad Ridhay ◽  
Moh. Mirzan ◽  
Syamsuddin
Keyword(s):  
Molecular Weight ◽  
Water Content ◽  
Functional Groups ◽  
Isopropyl Alcohol ◽  
Functional Group ◽  
Extraction Time ◽  
Glycosidic Bond ◽  
Bending Vibration ◽  
High Carbohydrate ◽  
Stretching Vibration

Gembili bulbs (Dioscorea esculenta L.) have a fairly high carbohydrate content, so they can potentially be a new source of glucomannan compounds. This study aims to determine the yield and glucomannan characteristics of Gembili bulbs at different extraction times and temperatures. Glucomannan was obtained by extraction with water at temperatures of 45, 60, 75, 90, and 105oC for 45, 60, 75, 90, and 105 minutes, and precipitated with isopropyl alcohol. The results showed that the highest yield was obtained at the extraction time of 90 minutes and a temperature of 105oC of 53.09%. The glucomannan of Gembili bulb has a molecular weight of 1,865 x 104 g/mol with ash and water content values of 0.866% and 10.45%, respectively. The results of identification of functional groups with an FTIR spectrophotometer showed that there was a functional group stretching vibration of glucomannan compounds, including the –OH group at a wavenumber of 3431 cm-1 and -C-O-C (glycosidic bond) at a wavenumber of 1020.34 cm-1 and bending vibration of -CH functional groups on wavenumber of 850.61 cm-1.

FTIR STUDY ON MOLECULAR CONTAMINATION ON SURFACE OF OPTICAL MATERIALS

2006 ◽  
Vol 20 (25n27) ◽  
pp. 3860-3865 ◽  
Author(s):  
MASAHIRO KATOH ◽  
NOBUAKI OKANO ◽  
TOSHIHIDE HORIKAWA ◽  
TAHEI TOMIDA ◽  
NOBUNARI ITOH
Keyword(s):  
Ir Spectra ◽  
Optical Materials ◽  
Functional Group ◽  
The Other ◽  
Absorption Bands ◽  
Bending Vibration ◽  
Absorption Intensity ◽  
Stretching Vibration ◽  
Optical Disks ◽  
Molecular Contaminants

The IR spectra of the molecular contaminants on surface of optical materials were measured. The optical disks used were SiO 2, BK7 ( SiO 2 70%, B 2 O 3 10%, K 2 O 8%, N 2 O 8%), CaF 2, ZnSe and Al 2 O 3. N 2, O 2, H 2 O , and CO 2 were adopted as contamination gases. IR spectra of H 2 O (2.7kPa) on BK7 at 373K showed two absorption bands ( OH stretching vibration: around 4000cm-1-3500cm-1 and OH bending vibration: around 2000cm-1-1500cm-1). The absorption intensity decreased with a decrease in temperature and a new band (around 3250cm-1) appeared at 173K. The new band was attributed to phase transition of H 2 O . These phenomena were also observed on the other three discs, except for SiO 2. IR spectra of SiO 2 showed OH stretching band (3676cm-1). The absorption intensity decreased with a decrease in temperature. But two new bands (3720cm-1 and 3620cm-1) appeared under an atmosphere of N 2 (66.5kPa), O 2 (66.5kPa), H 2 O (2.7kPa) or CO 2 (0.7 or 13.3kPa). A similar phenomenon was also observed for BK7, which has OH group. These results suggested the functional group of SiOH interacted with contamination molecules.

scholarly journals The Effects of Fire on Organic Functional Groups of Peat in Relation to Water Content

2015 ◽  
Vol 19 (3) ◽  
pp. 143
Author(s):  
Said Ramadhan ◽  
Fadly Hairannoor Yusran ◽  
Abdul Haris ◽  
Suhaili Asmawi
Keyword(s):  
Moisture Content ◽  
Water Content ◽  
Functional Groups ◽  
Functional Group ◽  
Water Levels ◽  
Time Interval ◽  
Total Acidity ◽  
Organic Functional Group ◽  
Organic Functional Groups ◽  
The Relationship

The aim of this research was to study the decline of organic functional group through the process of burning in peat. In addition, this study was also to examine the relationship between water content in peat and organic functional group after combustion (burning).  Peat drying was conducted in an oven at a temperature of 75°C with the interval of 0, 1, 2, 3, 4, 5 and 6 hours.  Each time interval had three replicates within two sets of experiments so that the total number of samples were 42 (experimental units).  Variables measured were moisture content, total acidity, COOH groups, and OH-phenolate.  The relationship between the water content with total acidity, COOH groups and OH-phenolate were determined by the equation y = bx + a.  The results showed that the relationship between the water content with organic functional group was linear.  While the relationship between peat water content with organic functional group after burning was irregular, although water levels through the process of burning have been greatly reduced. Keywords: Burning peat; organic functional groups; water content [How to Cite: Said R, FH Yusran, A Haris and S Asmawi. 2014. The Effects of Fire on Organic Functional Groups of Peat in Relation to Water Content. J Trop Soils 19: 143-149. Doi: 10.5400/jts.2014.19.3.143]    

scholarly journals Incorporation of amine functional group on surface of hydroxyapatite prepared fromstriped catfish (Pagasianodon hypophthalmus) bone

2021 ◽  
Vol 13 (Aquaculture) ◽  
pp. 64-72
Author(s):  
Quoc Phong Ho ◽  
Takagi Yasuaki ◽  
Lien Huong Huynh ◽  
Thanh Tuyen Nguyen ◽  
Minh Phu Tran ◽  
...  
Keyword(s):  
Reaction Time ◽  
Water Content ◽  
Functional Groups ◽  
Functional Group ◽  
X Ray Diffraction ◽  
X Ray ◽  
Grafting Efficiency ◽  
Grafting Reaction ◽  
Striped Catfish ◽  
Surface Modified

This study was conducted to incorporate amine functional groups on the surface of hydroxyapatite to enhance its potential application in biomedical materials. Hydroxyapatite particles (HA) were synthesized from striped catfish (Pagasianodon hypophthalmus) bone and surface modified by grafting with (3-aminopropyl)triethoxysilane (APTES). Important factors affected grafting efficiency such as concentration of APTES, water content, reaction temperature and reaction time were studied. X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and Scanning electron microscopy (SEM) were used to confirm the grafting reaction on HA surfaces. Grafting efficiency was evaluated based on intensity of characteristic absorption peaks of APTES. The experimental results showed that amine functional groups were successfully introduced on HA surface at optimal condition of 0.2 M APTES, 0.75 wt.% water content, at 60°C and 12-hour reaction time.

scholarly journals Resilience of Epiphytic Lichens to Combined Effects of Increasing Nitrogen and Solar Radiation

2021 ◽  
Vol 7 (5) ◽  
pp. 333
Author(s):  
Lourdes Morillas ◽  
Javier Roales ◽  
Cristina Cruz ◽  
Silvana Munzi
Keyword(s):  
Global Change ◽  
Solar Radiation ◽  
Functional Groups ◽  
Physiological Response ◽  
Functional Group ◽  
Environmental Drivers ◽  
Combined Effects ◽  
Environmental Stressor ◽  
Comprehensive Understanding ◽  
Direct Sunlight

Lichens are classified into different functional groups depending on their ecological and physiological response to a given environmental stressor. However, knowledge on lichen response to the synergistic effect of multiple environmental factors is extremely scarce, although vital to get a comprehensive understanding of the effects of global change. We exposed six lichen species belonging to different functional groups to the combined effects of two nitrogen (N) doses and direct sunlight involving both high temperatures and ultraviolet (UV) radiation for 58 days. Irrespective of their functional group, all species showed a homogenous response to N with cumulative, detrimental effects and an inability to recover following sunlight, UV exposure. Moreover, solar radiation made a tolerant species more prone to N pollution’s effects. Our results draw attention to the combined effects of global change and other environmental drivers on canopy defoliation and tree death, with consequences for the protection of ecosystems.

scholarly journals Effects of Molecular Weight of Functionalized Liquid Butadiene Rubber as a Processing Aid on the Properties of SSBR/Silica Compounds

Polymers ◽  
2021 ◽  
Vol 13 (6) ◽  
pp. 850
Author(s):  
Donghyuk Kim ◽  
Byungkyu Ahn ◽  
Kihyun Kim ◽  
JongYeop Lee ◽  
Il Jin Kim ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Anionic Polymerization ◽  
High Performance ◽  
Crosslink Density ◽  
Functional Group ◽  
Vital Role ◽  
Butadiene Rubber ◽  
Molecular Weights ◽  
Mooney Viscosity ◽  
Silica Dispersion

Liquid butadiene rubber (LqBR) which used as a processing aid play a vital role in the manufacturing of high-performance tire tread compounds. However, the studies on the effect of molecular weight, microstructure, and functionalization of LqBR on the properties of compounds are still insufficient. In this study, non-functionalized and center-functionalized liquid butadiene rubbers (N-LqBR and C-LqBR modified with ethoxysilyl group, respectively) were synthesized with low vinyl content and different molecular weights using anionic polymerization. In addition, LqBR was added to the silica-filled SSBR compounds as an alternative to treated distillate aromatic extract (TDAE) oil, and the effect of molecular weight and functionalization on the properties of the silica-filled SSBR compound was examined. C-LqBR showed a low Payne effect and Mooney viscosity because of improved silica dispersion due to the ethoxysilyl functional group. Furthermore, C-LqBR showed an increased crosslink density, improved mechanical properties, and reduced organic matter extraction compared to the N-LqBR compound. LqBR reduced the glass transition temperature (Tg) of the compound significantly, thereby improving snow traction and abrasion resistance compared to TDAE oil. Furthermore, the energy loss characteristics revealed that the hysteresis loss attributable to the free chain ends of LqBR was dominant.

Specific Volume−Hole Volume Correlations in Amorphous Carbohydrates: Effect of Temperature, Molecular Weight, and Water Content

2010 ◽  
Vol 114 (4) ◽  
pp. 1568-1578 ◽  
Author(s):  
Sam Townrow ◽  
Mina Roussenova ◽  
Maria-Isabelle Giardiello ◽  
Ashraf Alam ◽  
Job Ubbink
Keyword(s):  
Molecular Weight ◽  
Water Content ◽  
Specific Volume ◽  
Effect Of Temperature

scholarly journals Food Additives Frequency in processed baby products in Cochabamba, Bolivia

2021 ◽  
Vol 17 (Especial) ◽  
pp. 19-27
Author(s):  
Nelcy Aguilar Sasari ◽  
Milenka Alessandra Fernández Ledezma ◽  
Tania Araujo-Burgos
Keyword(s):  
Shelf Life ◽  
Functional Groups ◽  
Frequency Analysis ◽  
Metropolitan Area ◽  
Sodium Nitrate ◽  
Functional Group ◽  
Food Additives ◽  
Processed Food ◽  
Food Labels ◽  
Organoleptic Properties

Additives are necessary substances to improve the nutritional and organoleptic properties and the shelf life of processed food. In addition, their use is regulated, and it must be declared on the food labels. Thus, the objective of this research was to determine the frequency of food additives in processed baby products in Cochabamba metropolitan area (Bolivia). Data were collected by label reading and a frequency analysis was performed by additives and by functional group. 26 baby products were found where 41 food additives were identified with an occurrence of 256 times, and a mean of 9,8 additives per product. Moreover, the functional groups most widely used are antioxidants and colorants. Finally, the most frequent additives are mostly harmless, except for sodium nitrate and copper sulfate.

scholarly journals Phytochemical Screening, Spectrum Profile of Functional Groups, and Effervescent Formulation of Kepok Banana Peels Stem Extract

2021 ◽  
Vol 4 (2) ◽  
pp. 66-72
Author(s):  
Robby Candra Purnama ◽  
Annisa Primadiamanti
Keyword(s):  
Fourier Transform ◽  
Infrared Spectroscopy ◽  
Secondary Metabolites ◽  
Functional Groups ◽  
Functional Group ◽  
Screening Method ◽  
Phytochemical Screening ◽  
Stem Extract ◽  
Group Profile ◽  
Banana Stem

Kepok banana plants contain secondary metabolites such as tannins and flavonoids. Tannins and flavonoids have various properties for human health. Research has been carried out to identify secondary metabolite compounds (tannins, flavonoids, and saponins) by using the phytochemical screening method to see the functional group profile contained in the extract of kepok banana stem waste. Kepok banana stem waste was extracted in 96% ethanol, then evaporated and screened phytochemically. This extract was used to prepare effervescently. Screening results showed that tannin and flavonoids were identified by the appearance of the following color black-green and dark red, respectively. Meanwhile, saponins were negative because the foam formed had a height of 0.3 cm and did not meet the saponins' positive requirements (1-3 cm high foam and stable for 5 minutes). Identification of functional groups in the extract of kepok banana stem waste using Fourier-transform Infrared Spectroscopy (FTIR) showed that C-C stretching in the area 2927.24 cm-1, O-H stretching in the 3423.87 cm-1 area, C=O stretching in the 1648.87 cm-1 area. Also appeared bending CH2 in the region of 1421.45 cm-1, and C-C in the area of 1149.98 cm-1. The characteristics of three different formulas (A, B, and C) of effervescent have been investigated: the moisture content of 2.51%; 2.55%, and 2.52%, respectively. Then, flow rate of 8.81 g/s; 8.83 g/s; and 8.82 g/s, compressibility of 14.5%; 14.4%; and 14.5%, and a pH of 5.97; 5.98; and 5.97 respectively. All parameters are eligible.

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