scholarly journals Effect of Temperature on Biological Macromolecules of Three Microalgae and Application of FT-IR for Evaluating Microalgal Lipid Characterization

ACS Omega ◽  
2020 ◽  
Vol 5 (51) ◽  
pp. 33262-33268
Author(s):  
Ting Zhao ◽  
Xiaotian Han ◽  
Huidi Cao
Keyword(s):  
Effect Of Temperature ◽  
Biological Macromolecules ◽  
Ft Ir ◽  
Lipid Characterization

scholarly journals PENGARUH SUHU DAN KECEPATAN PENGADUKAN PADA PROSES PEMBUATAN SURFAKTAN NATRIUM LIGNOSULFONAT DARI TEMPURUNG KELAPA

2013 ◽  
Vol 2 (1) ◽  
pp. 21-25
Author(s):  
Jhon Peri Rinaldo Sirait ◽  
Nico Sihombing ◽  
Zuhrina Masyithah
Keyword(s):  
Base Material ◽  
Sodium Bisulfite ◽  
Coconut Shell ◽  
Effect Of Temperature ◽  
Agitation Rate ◽  
Reactant Ratio ◽  
Ir Spectrophotometry ◽  
Ft Ir ◽  
Coconut Shell Powder ◽  
Shell Powder

Coconut shell is one of agricultural wastes that having low commercial value. This research is objected to use coconut shell as the base material of producing surfactant. The use of coconut shell is basically due to its content of lignin, about 29,4%. The objective of this research is to obtain isolate lignin with increasing chatalis NaOH and H2SO4 with lignin identification, the effect of temperature and agitation rate of producing surfactant. The research was done in a reactor with temperature of 100 0C, 110 0C, 120 0C, 3 hours reaction time, pH 6, 80 rpm, 90 rpm, 100 rpm agitation rate, and coconut shell as the base material. Dry coconut shell is grinded and the powder is collected to be reacted. The coconut shell powder is reacted with sodium bisulfite solution with variation in ratio of 1:0,5.  The product is filtered to get filtrate and residue. The filtrate is further analyzed by using the FT-IR spectrophotometry method. From the research we get maximum purity of surfactant at sodium bisulfite with reactant ratio of 1:0,5;  Speed 100 rpm and temperature 120 0C.

Effect of Temperature Variation on FT-IR Spectrometer Stability

1997 ◽  
Vol 51 (1) ◽  
pp. 43-50 ◽  
Author(s):  
D. M. MacBride ◽  
C. G. Malone ◽  
J. P. Hebb ◽  
E. G. Cravalho
Keyword(s):  
Temperature Variation ◽  
Thermal Instability ◽  
Effect Of Temperature ◽  
Optical Bench ◽  
Infrared Source ◽  
Ft Ir ◽  
Purge Gas ◽  
Response Variation ◽  
Spectrometer Response ◽  
Gas Supply

The effect of temperature variation on Fourier transform infrared (FT-IR) spectrometer response stability is investigated for wavenumbers from 10,000 to 100 cm−1 with the use of a temperature measurement and data acquisition system on the spectrometer optical bench. Spectrometer response instability is correlated with local temperature variation for two FT-IR spectrometer systems, with the use of various infrared source, beamsplitter, and detector combinations. The data obtained show that detector responsivity variation and beamsplitter misalignment associated with thermal instability of the spectrometer optical bench are responsible for the observed response instability. Response variation of up to 4% per °C temperature variation is observed. Variations of the laboratory environment and spectrometer purge gas supply temperatures are shown to affect spectrometer thermal stability directly.

scholarly journals Hydrogenative Cyclization of Levulinic Acid to γ-Valerolactone with Methanol and Ni-Fe Bimetallic Catalysts

Catalysts ◽  
2020 ◽  
Vol 10 (9) ◽  
pp. 1096
Author(s):  
Ligang Luo ◽  
Xiao Han ◽  
Qin Zeng
Keyword(s):  
Photoelectron Spectroscopy ◽  
Levulinic Acid ◽  
Hydrogen Donor ◽  
Effect Of Temperature ◽  
X Ray ◽  
Transmission Electron ◽  
Ft Ir ◽  
Temperature Programmed

A series of Ni-Fe/SBA-15 catalysts was prepared and tested for the catalytic hydrogenation of levulinic acid to γ-valerolactone, adopting methanol as the only hydrogen donor, and investigating the synergism between Fe and Ni, both supported on SBA-15, towards this reaction. The characterization of the synthesized catalysts was carried out by XRD (X-ray powder diffraction), TEM (transmission electron microscopy), H2-TPD (hydrogen temperature-programmed desorption), XPS (X-ray photoelectron spectroscopy), and in situ FT-IR (Fourier transform–infrared spectroscopy) techniques. H2-TPD and XPS results have shown that electron transfer occurs from Fe to Ni, which is helpful both for the activation of the C=O bond and for the dissociative activation of H2 molecules, also in agreement with the results of the in situ FT-IR spectroscopy. The effect of temperature and reaction time on γ-valerolactone production was also investigated, identifying the best reaction conditions at 200 °C and 180 min, allowing for the complete conversion of levulinic acid and the complete selectivity to γ-valerolactone. Moreover, methanol was identified as an efficient hydrogen donor, if used in combination with the Ni-Fe/SBA-15 catalyst. The obtained results are promising, especially if compared with those obtained with the traditional and more expensive molecular hydrogen and noble-based catalysts.

scholarly journals MODEL KINETIKA EKSTRAKSI FLAVONOID DARI BAYAM MERAH (Alternanthera amoena voss)

2018 ◽  
Vol 6 (4) ◽  
pp. 8-14
Author(s):  
Iriany ◽  
Irsa Septiawan ◽  
Salwa Jody Gustia
Keyword(s):  
Mass Transfer ◽  
Transfer Coefficient ◽  
Mass Transfer Coefficient ◽  
Total Content ◽  
Effect Of Temperature ◽  
Polyphenol Compounds ◽  
Water Solvent ◽  
Ir Spectrophotometry ◽  
Ft Ir

Red spinach (Alternanthera amoena voss) contains vitamins, protein, and flavonoids. Flavonoid is polyphenol compounds having properties as a free radical catcher.The purpose of this research is to obtain the kinetic rate of flavonoid mass transfer from red spinach.Extraction is one of the way to take flavonoids contained in solids with the assist of solvents. Mass transfer in liquid solid extraction occurs by diffusion. The determination of mass transfer coefficient (KC) is to conduct the rate of mass transfer of flavonoids from solids. In this study, the effect of temperature on the extraction of flavonoids from red spinach with water solvent is observed. The temperatures extraction in this research are of 50°C, 60°C, and 70°C respectively. Determinationof total flavonoid, mass transfer coefficient, and antioxidant activity carried out using FT-IR Spectrophotometry and UV-VIS Spectrophotometry. This study concluded that the increase in extraction time and temperature will increase the total content of flavonoids and extract rendement.Mass transfer coefficient equation in this study is K = 3078645 . Antioxidants in red spinach are included in the group of very strong antioxidants.

Evaluation of FT-IR and Nile Red methods for microalgal lipid characterization and biomass composition determination

2013 ◽  
Vol 128 ◽  
pp. 107-112 ◽  
Author(s):  
Guo-Dong Feng ◽  
Fang Zhang ◽  
Li-Hua Cheng ◽  
Xin-Hua Xu ◽  
Lin Zhang ◽  
...  
Keyword(s):  
Nile Red ◽  
Biomass Composition ◽  
Composition Determination ◽  
Ft Ir ◽  
Lipid Characterization

scholarly journals Desulfurisasi Katalitik Tiofen Menggunakan Katalis CoMo/USY dalam Reaktor Batch

2018 ◽  
Vol 14 (1) ◽  
pp. 136 ◽  
Author(s):  
Khoirina Dwi Nugrahaningtyas ◽  
Nanda Pratiwi ◽  
Eddy Heraldy
Keyword(s):  
Batch Reactor ◽  
Catalyst Activity ◽  
Product Yield ◽  
Effect Of Temperature ◽  
Temperature Range ◽  
Activity Test ◽  
Character Variation ◽  
Ft Ir ◽  
Increasing Temperature ◽  
Desulfurization Activity

<p>Telah dilakukan uji aktivitas katalis CoMo/USY pada reaksi desulfurisasi tiofen. Reaksi dilakukan pada reaktor sistem batch dengan tekanan gas N<sub>2</sub> sebesar 1 bar gas N<sub>2</sub> dan waktu reaksi selama 1 jam. Penelitian ini bertujuan untuk mengetahui pengaruh variasi temperatur dan variasi karakter katalis pada reaksi desulfurisasi tiofen. Product desulfurisasi dianalisis dengan GC-MS. Karakter kestabilan struktur katalis dilihat dengan analisis menggunakan instrument FT-IR. Hasil analisis terhadap uji aktivitas desulfurisasi menunjukkan bahwa pada rentang temperatur 200-300°C, rendemen bertambah dengan meningkatnya temperatur. Adapun efek karakter katalis terhadap aktivitas katalitiknya menunjukkan bahwa karakter katalis yang paling dominan adalah sifat keasaman. Katalis dengan keasaman tertinggi, yaitu katalis CoMo/USY, memiliki aktivitas tertinggi dalam desulfurisasi tiofen dengan rendemen produk sebesar 2,88%. Hasil analisis FT-IR terhadap katalis bekas menunjukkan bahwa struktur cukup stabil dan tidak ada pengotor yang terikat pada katalis.</p><p><strong>Catalytic Desulfurization of Thiophene </strong><strong>using</strong><strong> Como/Usy Catalyst </strong><strong>in</strong><strong> Batch Reactor</strong>. CoMo/USY catalyst activity has been tested for thiophene desulfurization reaction. The reaction was carried out in batch system reactor with N<sub>2</sub> gas pressure of 1 bar and reaction time for 1 hour. This study aims to determine the effect of temperature variation and catalyst character variation in thiophene desulfurization reaction. The desulfurization products were analyzed by <em>Gas Chromatography - Mass Spectra </em>(GC-MS). The characters of structure catalyst were analyzed by <em>Fourier Transform Infrared Spectroscopy</em> (FT-IR). The results of the analysis of the desulfurization activity test showed that in the temperature range 200-300 °C, the yield raised with increasing temperature The analysis results of the desulfurization activity test showed that in the temperature range of 200-300°C, the yield raised with increasing temperature. The effect of the catalysts character on its catalytic activity shows that the most dominant character of the catalysts were its acidity. The highest acidity catalyst, CoMo/USY catalyst, has highest activity in thiophene thiophene with the product yield of 2,88%. The result of the FTIR analysis on used catalyst show that the structure was stable and no impurities were attached the catalyst.</p>

scholarly journals Krokot (Portulaca oleracea L) As a Natural Sensitizer for TiO2 Dye-sensitized Solar Cells: The Effect of Temperature Extract

2015 ◽  
Vol 4 (2) ◽  
pp. 25
Author(s):  
Reyza Anni Mufidah ◽  
Khamidinal Khamidinal ◽  
Endaruji Sedyadi ◽  
Didik Krisdiyanto
Keyword(s):  
Wave Length ◽  
Dye Sensitized Solar Cells ◽  
Visible Region ◽  
Hydroxyl Group ◽  
Effect Of Temperature ◽  
Uv Spectrum ◽  
Ito Glass ◽  
Ft Ir ◽  
Absorbance Peak ◽  
C 50

<p>The solar cell is formed by a sandwich structure, in which two electrodes flank the primary electrolyte that is containing redox I-/based on PEG (Polyethylene Glycol). The working-electrode which is TiO<sub>2</sub> layer on an ITO glass substrate is sensitized with krokot dye as the electron donor. The counter electrode is a layer of carbon. The fabrication cell is immersed with the krokot dye with 40°C, 50°C, 60°C extract temperature. The result of the UV-Vis shows that the absorption of wave-length from dye extract of krokot is located in the visible region with the absorbance peak in 420,5 nm and 665,5 nm which are the peak of chlorophyll. For the UV-Vis solid system, there are the highest band gap  in  50°C extract temperature that make the capability of absorption toward UV spectrum is large. Furthermore, in the functional group analysed by FT-IR, there are shiften-carbonil and hydroxyl group after they are sensitized. From the current and voltage test with I-V meter keithley 2400 is resulted that on the 50°C extract temperature produces the highest efficiency of reaches which is 2.63 x 10<sup>-3</sup> %.</p>

scholarly journals The Effect of Temperature, Sulfonation, and PEG Addition on Physicochemical Characteristics of PVDF Membranes and Its Application on Hemodialysis Membrane

2021 ◽  
Vol 21 (4) ◽  
pp. 942
Author(s):  
Retno Ariadi Lusiana ◽  
Ayub Indra ◽  
Nor Basid Adiwibawa Prasetya ◽  
Nurwarrohman Andre Sasongko ◽  
Parsaoran Siahaan ◽  
...  
Keyword(s):  
Membrane Permeability ◽  
Water Uptake ◽  
Polyvinylidene Fluoride ◽  
Bath Temperature ◽  
Physicochemical Characteristics ◽  
Effect Of Temperature ◽  
Coagulation Bath ◽  
Pvdf Membrane ◽  
Swelling Degree ◽  
Ft Ir

Polyvinylidene fluoride (PVDF) membrane and its derivative have been investigated the permeation ability for creatinine and urea. The membrane was made by an inversion precipitation system in N,N-dimethyl acetamide (DMAc) and water as non-solvents. In this study, the modification of PVDF membrane permeability with PEG additives, CBT variations, and sulfonation was successfully carried out. The membrane solidification process was carried out on three variations of the coagulation bath temperature (CBT): 30, 45, and 60 °C. Eight types of membranes were characterized by using FT-IR and TGA/DSC, followed by the analysis of their porosity, hydrophilicity, water uptake, swelling degree, tensile strength, and permeability of creatinine and urea. The FT-IR spectra indicate that PVDF modification has been successfully carried out. The porosity, hydrophilicity, water uptake, and swelling degree values increase with the modification of functional groups. Furthermore, improvements in creatinine and urea permeability and clearances are achieved by increasing CBT and sulfonation in the PVDF/PEG membrane. The presence of sulfonate groups improves the membrane permeability through the interaction of intermolecular hydrogen with water and dialysate compounds. The existence of PEG as a porogen enhanced membrane porosity. Creatinine and urea clearance values increase from 0.29–0.58 and 6.38–20.63 mg/dL, respectively.

Sign in / Sign up

Export Citation Format

Share Document