Encapsulation of Nanometer CaCO3 by Polymer Network

2005 ◽  
Vol 475-479 ◽  
pp. 1005-1008
Author(s):  
Wen Fang Liu ◽  
Zhao Xia Guo ◽  
Jian Yu
Keyword(s):  
Stearic Acid ◽  
Ir Spectra ◽  
Direct Evidence ◽  
Polymer Network ◽  
Composite Particles ◽  
Continuous Mode ◽  
Batch Mode ◽  
Polyfunctional Monomer ◽  
Divinyl Benzene ◽  
Ft Ir

Stearic acid coated nanometer CaCO3 was encapsulated by polystyrene (PS) network via emulsion polymerization, where a polyfunctional monomer trimethyol propane trimethacrylate (TMPTMA) or divinyl benzene (DVB) was used as crosslinker. The feed modes of monomer and initiator are investigated. Batch mode is shown to be more convenient than semi-continuous mode in view of network perfection. With the amount of crosslinkers increased from 1 wt% to 7 wt%, the percentage of unextractable PS is high (not lower than 95%) for all samples in the system of TMPTMA, while this value decreases sharply from 74% to 3% in the system of DVB. The yield in the system of DVB is higher than that of TMPTMA. With increased amount of CaCO3, encapsulation ratio can be varied from 5.2 to 2.6, while the yield and unextractable PS decrease. FT-IR spectra of the products after extraction indicate tight encapsulation between PS and CaCO3, and TEM photographs of composite particles give direct evidence of encapsulation.

Nondestructive Analysis of Biological Materials by FT-IR-ATR. Method I: Direct Evidence for the Existence of Collagen Helix Structure in Lens Capsule

1989 ◽  
Vol 43 (1) ◽  
pp. 138-141 ◽  
Author(s):  
Y. Ozaki ◽  
F. Kaneuchi ◽  
T. Iwamoto ◽  
M. Yoshiura ◽  
K. Iriyama
Keyword(s):  
Ir Spectra ◽  
Direct Evidence ◽  
Lens Capsule ◽  
Random Coil ◽  
Albino Rabbit ◽  
Difference Spectra ◽  
Type Iv ◽  
Ir Frequencies ◽  
Ft Ir ◽  
Rabbit Lens

FT-IR spectra were measured in situ for an albino rabbit lens capsule by use of the ATR method, and the spectrum of water was subtracted. The obtained difference spectra resemble the spectrum of purified Type IV collagen in aqueous solution and show intense bands at 1637 and 1553 cm−1 assignable to the amide I and II modes, respectively. These frequencies are very close to those of the amide I and II bands of a 31 helix. This is direct evidence for the existence of the so-called collagen helix (a slightly modified 31 helix) in the lens capsule. FT-IR spectra were also measured by the diffuse reflectance method for the dried capsule stripped from a dried lens. IR frequencies of the amide I and II bands of the capsule collagen shift from 1637 and 1553 cm−1 to 1654 and 1540 cm−1, respectively, upon going from the intact capsule to the dried one, showing that the collagen helix is converted to a random coil structure upon drying.

Light- or Dark-Colored, L-DOPA-Based Melanins

2018 ◽  
Author(s):  
Koen Vercruysse ◽  
Margaret M. Whalen
Keyword(s):  
Human Physiology ◽  
Ir Spectra ◽  
Immune Cells ◽  
Chemical Properties ◽  
Chemical Signature ◽  
Ft Ir

<p>This report is a continuation of previous research on the H<sub>2</sub>O<sub>2</sub>-mediated synthesis of melanin-like pigments. We synthesized and characterized L-DOPA-based pigments using air- or H<sub>2</sub>O<sub>2</sub>-mediated<sub> </sub>oxidation. We compared their physic-chemical properties and evaluated their capacity to affect the interleukin release from immune cells. The use of higher concentrations of H<sub>2</sub>O<sub>2</sub> resulted in melanin-like materials with a distinct chemical signature in their FT-IR spectra and a lighter color. All pigments enhanced the interleukin release from immune cells. The possibility that lighter-colored melanins can be generated is discussed in the context of the importance of melanin-based pigmentation in human physiology.</p>

Growth Characteristics of Activated Sludges Acclimated to para-Nitrophenol in Batch and Continuous Modes

1994 ◽  
Vol 29 (7) ◽  
pp. 327-333
Author(s):  
Y. Matsui ◽  
F. Yamaguchi ◽  
Y. Suwa ◽  
Y. Urushigawa
Keyword(s):  
Growth Characteristics ◽  
The Other ◽  
Operational Mode ◽  
Continuous Mode ◽  
Relative Resistance ◽  
Batch Mode ◽  
The Given ◽  
Operational Modes ◽  
Very High ◽  
Sensitive Group

Activated sludges were acclimated to p-nitrophenol (PNP) in two operational modes, a batch and a continuous. The operational mode of the PNP acclimation of activated sludges strongly affected the physiological characteristics of predominant microorganisms responsible for PNP degradation. Predominant PNP degraders in the sludge in batch mode (Sludge B) had lower PNP affinity and were relatively insensitive to PNP concentration. Those of the sludge in continuous mode (Sludge C), on the other hand, had very high PNP affinity and were sensitive to PNP. MPN enumeration of PNP degraders in sludge B and C using media with different PNP concentrations (0.05, 0.2,0.5 and 2.0 mM) supported the above results. Medium with 0.2 mM of PNP did not recover PNP degraders in sludge C well, while it recovered PNP degraders in sludge B as well as the medium with 0.05 mM did. When switching from one operational mode to the other, the predominant population in sludge B shifted to the sensitive group, but that of sludge C did not shift at the given loading of PNP, showing relative resistance to inhibitive concentration.

scholarly journals Spectroscopy as a useful tool for the identification of changes with time in post-mortem vitreous humor for forensic toxicology purposes

2021 ◽  
Author(s):  
Anna Wójtowicz ◽  
Agata Mitura ◽  
Renata Wietecha-Posłuszny ◽  
Rafał Kurczab ◽  
Marcin Zawadzki
Keyword(s):  
Ir Spectra ◽  
Forensic Toxicology ◽  
Principal Component ◽  
Hierarchical Cluster ◽  
Vitreous Humor ◽  
Attenuated Total Reflection ◽  
Glass Slides ◽  
Added Benefit ◽  
Ft Ir ◽  
Non Destructive

AbstractVitreous humor (VH) is an alternative biological matrix with a great advantage of longer availability for analysis due to the lack of many enzymes. The use of VH in forensic toxicology may have an added benefit, however, this application requires rapid, simple, non-destructive, and relatively portable analytical analysis methods. These requirements may be met by Fourier transform infrared spectroscopy technique (FT-IR) equipped with attenuated total reflection accessory (ATR). FT-IR spectra of vitreous humor samples, deposited on glass slides, were collected and subsequent chemometric data analysis by means of Hierarchical Cluster Analysis and Principal Component Analysis was conducted. Differences between animal and human VH samples and human VH samples stored for diverse periods of time were detected. A kinetic study of changes in the VH composition up to 2 weeks showed the distinction of FT-IR spectra collected on the 1st and 14th day of storage. In addition, data obtained for the most recent human vitreous humor samples—collected 3 and 2 years before the study, presented successful discrimination of all time points studied. The method introduced was unable to detect mephedrone addition to VH in the concentration of 10 µg/cm3. Graphic abstract

scholarly journals Batch and Semi-Continuous Anaerobic Digestion of Industrial Solid Citrus Waste for the Production of Bioenergy

Processes ◽  
2021 ◽  
Vol 9 (4) ◽  
pp. 648
Author(s):  
Erik Samuel Rosas-Mendoza ◽  
Andrea Alvarado-Vallejo ◽  
Norma Alejandra Vallejo-Cantú ◽  
Raúl Snell-Castro ◽  
Sergio Martínez-Hernández ◽  
...  
Keyword(s):  
Anaerobic Digestion ◽  
Oxygen Demand ◽  
Continuous Mode ◽  
Citrus Industry ◽  
Batch Mode ◽  
Volatile Solids ◽  
Working Volume ◽  
Plant Level ◽  
Citrus Waste ◽  
Mesophilic Conditions

The aim of this paper is to describe a study of the anaerobic digestion of industrial citrus solid waste (ISCW) in both batch and semi-continuous modes for the production of bioenergy without the elimination of D-limonene. The study was conducted at the pilot plant level in an anaerobic reactor with a working volume of 220 L under mesophilic conditions of 35 ± 2 °C. Cattle manure (CM) was used as the inoculum. Three batches were studied. The first batch had a CM/ISCW ratio of 90/10, and Batches 2 and 3 had CM/ISCW ratios of 80/20 and 70/30, respectively. In the semi-continuous mode an OLR of approximately 8 g total chemical oxygen demand (COD)/Ld (4.43 gVS/Ld) was used. The results showed that 49%, 44%, and 60% of volatile solids were removed in the batch mode, and 35% was removed in the semi-continuous mode. In the batch mode, 0.322, 0.382, and 0.316 LCH4 were obtained at STP/gVSremoved. A total of 24.4 L/d (34% methane) was measured in the semi-continuous mode. Bioenergy potentials of 3.97, 5.66, and 8.79 kWh were obtained for the respective batches, and 0.09 kWh was calculated in the semi-continuous mode. The citrus industry could produce 37 GWh per season. A ton of processed oranges has a bioenergy potential of 162 kWh, which is equivalent to 49 kWh of available electricity ($3.90).

Luminescent Properties of Zn2SiO4:Eu3+,Dy3+ Phosphors via Sol-Gel Process

2012 ◽  
Vol 217-219 ◽  
pp. 733-736
Author(s):  
Xiu Mei Han ◽  
Shu Ai Hao ◽  
Ying Ling Wang ◽  
Gui Fang Sun ◽  
Xi Wei Qi
Keyword(s):  
Thermal Analysis ◽  
Ir Spectra ◽  
Sol Gel ◽  
Luminescent Properties ◽  
Photoluminescence Spectra ◽  
X Ray Diffraction ◽  
X Ray ◽  
Sol Gel Process ◽  
Ft Ir

Zn2SiO4:Eu3+, Dy3+ phosphors have been prepared through the sol-gel process. X-ray diffraction (XRD), thermogravimetric and ddifferential thermal analysis (TG-DTA), FT-IR spectra and photoluminescence spectra were used to characterize the resulting phosphors. The results of XRD indicated that the phosphors crystallized completely at 1000oC. In Zn2SiO4:Eu3+,Dy3+ phosphors, the Eu3+ and Dy3+ show their characteristic red(613nm, 5D0-7F2), blue (481nm, 4F9/2–6H15/2) and yellow (577nm, 4F9/2–6H13/2) emissions.

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