scholarly journals Preparation of carboxymethyl-quaternized oligochitosan and its scale inhibition and antibacterial activity

2013 ◽  
Vol 4 (2) ◽  
pp. 65-75 ◽  
Author(s):  
Hui-xin Zhang ◽  
Dong-xue Sun ◽  
Yu-chao Zhu ◽  
Ting-ru Yang ◽  
Xiu-hong Jin ◽  
...  
Keyword(s):  
Calcium Sulfate ◽  
Oxygen Demand ◽  
Xrd Analysis ◽  
X Ray Diffraction ◽  
Static Test ◽  
X Ray ◽  
Microbial Inhibition ◽  
Scale Inhibition ◽  
Calcium Sulfate Scale ◽  
Ft Ir

Carboxymethyl-quaternized oligochitosan (CMQAOC) was prepared through carboxymethylization and N-quaternization of oligochitosan (OC) which was obtained from chitosan degradation. The structure was confirmed by Fourier transform infrared spectroscopy (FT-IR), 1H-NMR, and X-ray diffraction (XRD) analysis. The performances for both scale and microbial inhibition of CMQAOC were evaluated by static test and culture flask method, respectively. The results showed that the scale inhibition rate for calcium carbonate and calcium sulfate scale were both beyond 80% with a CMQAOC dosage of 20 mg/L. With a degree of substitution for quaternary ammonia of up to 0.74, the killing rate for saprophytic bacteria and sulfate-reducting bacteria was 98.9 and 100%, respectively. The ratio of biochemical oxygen demand/chemical oxygen demand (BOD5/COD) of CMQAOC was 0.45, showing that CMQAOC is as biodegradable as OC.

Identification of acid-insoluble filter-plugging compounds and optimal acid-washing procedures for tubular backpulse pressure filters

TAPPI Journal ◽  
2011 ◽  
Vol 10 (1) ◽  
pp. 17-23
Author(s):  
KEVIN TAYLOR ◽  
RICH ADDERLY ◽  
GAVIN BAXTER
Keyword(s):  
Calcium Sulfate ◽  
Membrane Filter ◽  
Sulfamic Acid ◽  
Xrd Analysis ◽  
Metal Sulfides ◽  
X Ray Diffraction ◽  
X Ray ◽  
Gypsum Formation ◽  
Acid Washing ◽  
Hydrolysis Of

Over time, performance of tubular backpulse pressure filters in kraft mills deteriorates, even with regular acid washing. Unscheduled filter replacement due to filter plugging results in significant costs and may result in mill downtime. We identified acid-insoluble filter-plugging materials by scanning electron microscope/energy-dispersion X-ray spectroscopy (SEM/EDS) and X-ray diffraction (XRD) analysis in both polypropylene and Gore-Tex™ membrane filter socks. The major filter-plugging components were calcium sulfate (gypsum), calcium phosphate (hydroxylapatite), aluminosilicate clays, metal sulfides, and carbon. We carried out detailed sample analysis of both the standard acid-washing procedure and a modified procedure. Filter plugging by gypsum and metal sulfides appeared to occur because of the acid-washing procedure. Gypsum formation on the filter resulted from significant hydrolysis of sulfamic acid solution at temperatures greater than 130°F. Modification of the acid-washing procedure greatly reduced the amount of gypsum and addition of a surfactant to the acid reduced wash time and mobilized some of the carbon from the filter. With surfactant, acid washing was 95% complete after 40 min.

A study on using expanded perlite with hydroxyapatite: Reinforced bio-composites

2021 ◽  
pp. 095441192199656
Author(s):  
Erdoğan Karip ◽  
Mehtap Muratoğlu
Keyword(s):  
Body Fluid ◽  
Xrd Analysis ◽  
Cold Isostatic Pressing ◽  
Expanded Perlite ◽  
X Ray Diffraction ◽  
Pressing Method ◽  
X Ray ◽  
Infra Red ◽  
Ft Ir

People are exposed to different kinds of diseases or various accidents in life. Hydroxyapatite (HA) has been widely employed for bone treatment applications. In this study, HA was extracted from sheep bones. Bio-composites were doped with 1, 5, and 10 wt.% of expanded perlite and 5 wt.% of ZrO2–MgO-P2O5. The bio-composites were prepared by the cold isostatic pressing method (250 MPa) and sintered at 900°C for 1 h. In order to evaluate the characteristics of the bio-composites, microhardness, density, X-ray diffraction (XRD), Fourier transform infra-red spectroscopy (FT-IR), scanning electron microscopy (SEM), and energy dispersive spectroscopy (EDS) analyses were carried out on them. Additionally, the specimens whose characteristics were determined were kept in synthetic body fluid (SBF), and their in vitro behavior was examined. As a result, it was observed that microhardness increased as both the weight and the grain size of the expanded perlite were increased. Calcium silicate, tri-calcium phosphate, and hydroxyapatite were observed in the XRD analysis of all samples, and the formation of apatite structures was increased by addition of ZrO2–MgO–P2O5.

The Characteristic Evaluation of Hydroxyapatite Powders Synthesized from CaCO3 Refined from Oyster Shell and H3PO4

2006 ◽  
Vol 118 ◽  
pp. 639-644
Author(s):  
Hye Sung Kim ◽  
Su Chak Ryu
Keyword(s):  
Bone Density ◽  
Inductively Coupled Plasma ◽  
Oyster Shell ◽  
Atomic Emission ◽  
Xrd Analysis ◽  
X Ray Diffraction ◽  
X Ray ◽  
Inductively Coupled ◽  
Infra Red ◽  
Ft Ir

Hydroxyapatite (Ca10(PO4)6(OH)2, HAp) powders is synthesized using the mixed powders of CaCO3 refined from oyster shells and phosphoric acid (H3PO4-98%, Daejung) as starting materials. The characteristic evaluation and chemical analysis of the synthesized powders is performed by X-ray diffraction (XRD), Fourier-transformed infra-red spectroscopy (FT-IR), and inductively-coupled plasma atomic emission spectroscopy (ICPAES). XRD analysis of synthetic powder by heat treatment at 1300°C for 2hrs shows only HAp peaks corresponding to stoichiometric HAp. It is confirmed by ICP-AES test that impurities such as Zn, In, Ti, Ba, Cd, Pb, and Mn, is not detected at all, but small amounts of Ti and Be is observed (0.099ppm Ti and 0.002ppm Ba). Variation of bone density is measured by giving medication of HAp powder with drinking water into human body continuously for three month. After the medication, the bone density is higher than the medication before. This means that HAp powder made from this process can be used as improver of bone density.

Research on the Thermal Decomposition Process of K-Feldspar-CaSO4-CaO System

2013 ◽  
Vol 734-737 ◽  
pp. 916-920 ◽  
Author(s):  
Jing Xia Chao ◽  
Ju Pei Xia ◽  
Chao Qin Yang ◽  
Zhao Shu Zhang ◽  
Xue Jiao Ren
Keyword(s):  
Thermal Decomposition ◽  
Calcium Sulfate ◽  
Xrd Analysis ◽  
Operating Conditions ◽  
Decomposition Process ◽  
Complex Reaction ◽  
X Ray Diffraction ◽  
Thermal Decomposition Process ◽  
X Ray

The thermal decomposition process of K-feldspar-CaSO4-CaO system was studied by X-ray diffraction (XRD) analysis of the product which calcined at 1473K. The results show that KAlSi3O8 firstly is decomposed into KAlSi2O6 and released the SiO2, then has a complex reaction between KAlSi2O6 and CaO, which generated intermediates-K2SiO3 under the operating conditions. K2SiO3 is unstable and reacted with calcium sulfate to generate K2SO4. When the CaO amount is insufficient, the main products are KAlSi2O6 and 2CaOAl2O3SiO2, the potassium existed as K2S2O8; when n (CaO) / n (KAS6) 12:1, the products will further transfer into CaOSiO2 and 2CaO SiO2 and the potassium existed as K2SO4.

Performance of a non-phosphorus antiscalant on inhibition of calcium-sulfate precipitation

2012 ◽  
Vol 66 (1) ◽  
pp. 193-200 ◽  
Author(s):  
Xiaoxu Xue ◽  
Change Fu ◽  
Na Li ◽  
Fangfang Zheng ◽  
Weiben Yang ◽  
...  
Keyword(s):  
Calcium Sulfate ◽  
Water Systems ◽  
Sem Analysis ◽  
Solution Ph ◽  
X Ray ◽  
Thermodynamics And Kinetics ◽  
Scale Inhibition ◽  
Calcium Sulfate Scale ◽  
Different Temperatures ◽  
Strong Ability

The aim of this study is to report on the performance of a novel non-phosphorus antiscalant, acrylic acid (AA)-allylpolyethoxy carboxylate (APEC), being developed for calcium-sulfate scale inhibition in industrial water systems. The performance of AA-APEC on calcium-sulfate scale inhibition was compared with that of the two commercial inhibitors, polyamino polyether methylene phosphonates (PAPEMP) and polyacrylic acid (PAA), containing the same polyethylene glycol segments or carboxyl functional groups as AA-APEC. The study indicated that AA-APEC could act as a highly effective calcium sulfate inhibitor, having strong ability to inhibit the precipitation of calcium sulfate at a dosage of 2 mg L−1, showing approximately 83.6% inhibition. The results also showed that AA-APEC dosage, the solution pH, inhibiting temperature, concentration of Ca2+, and SO42− all play important roles in inhibiting calcium-sulfate precipitation. The precipitation thermodynamics and kinetics at different temperatures were also discussed. X-ray diffractometer (XRD) and scanning electron microscope (SEM) analysis showed that AA-APEC strongly affected the texture and the morphology of the deposited calcium sulfate. Calcium sulfate has been inhibited through stabilization by adsorption onto crystal growth sites of nascent crystals altering their morphology.

scholarly journals Photocatalytic degradation of Direct Brown RN dye in the presence of ZnO nanoparticles

2015 ◽  
Vol 50 (1) ◽  
pp. 1-6 ◽  
Author(s):  
ASM A Islam ◽  
T Ferdous ◽  
AK Das ◽  
MM Karim ◽  
SM Masum
Keyword(s):  
Photocatalytic Degradation ◽  
Oxygen Demand ◽  
Major Constituent ◽  
Zno Nanoparticle ◽  
X Ray Diffraction ◽  
Reaction Conditions ◽  
X Ray ◽  
Treated Effluent ◽  
Optimum Reaction ◽  
Ft Ir

The ZnO nanoparticle was prepared by using Zn(NO3)2.6H2O and NaOH under optimum reaction conditions and the prepared nanoparticle was characterized by UV-visible spectroscopy, X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), energy dispersion X-ray spectroscopy (EDX) and scanning electron microscopy (SEM). The sunlight irradiated photocatalytic degradation of Direct Brown RN dye was studied using ZnO nanoparticle. The results of this investigation revealed that in the presence of sunlight, catalyst load of 0.5 g?L-1 and time of contact of 40 min, ZnO nanoparticle showed substantial capability of destroying Direct Brown RN dye from solution. An actual leather effluent containing Brown RN as a major constituent along with other dyes and dyeing auxiliaries was treated using ZnO and the reduction in the chemical oxygen demand (COD) of the treated effluent revealed almost complete destruction of the organic molecules along with color removal.Bangladesh J. Sci. Ind. Res. 50(1), 1-6, 2015

Montmorillonite Intercalated Norfloxacin and Tobramycin for New Drug-Delivery Systems

2020 ◽  
Vol 20 (8) ◽  
pp. 5246-5251
Author(s):  
El-Refaie Kenawy ◽  
Nehal O. Shaker ◽  
Mohamed Azaam ◽  
Aya S. Lasheen ◽  
Jianjian Lin ◽  
...  
Keyword(s):  
Drug Delivery ◽  
Drug Delivery Systems ◽  
Fourier Transforms ◽  
Xrd Analysis ◽  
Delivery Systems ◽  
Release Behavior ◽  
X Ray Diffraction ◽  
Release Rates ◽  
X Ray ◽  
Ft Ir

The urgent need of safe, therapeutically and patient-compliant drug delivery systems (DDSs) continuously stimulates researchers to explore novel tools and strategies to monitor the loading and release of drugs. In this context, this study demonstrates that montmorillonite clay (MMT) is an appropriate material for changing the release behavior of Tobramycin and Norfloxacin drugs into medium. The DDSs were prepared by the intercalation of Tobramycin or Norfloxacin between MMT layers. The MMT-drug systems were analyzed using X-ray diffraction (XRD) analysis, scanning electron microscope (SEM), and Fourier transforms infrared (FT-IR). After insertion of the drugs between the layers of MMT, the periodicity in c-axis changed because of the formation of layered hybrid structures. The release of drugs was investigated using UV-spectrophotometer. The release rates are found to be dependent on pH of the medium. Moreover, we found that the percentage of release increases as the pH increases, however the release rate is low. These findings would be beneficial for controlled release of drugs for prolonged time in the future.

scholarly journals Preparation and Characterization of Photoactive Anatase TiO2 from Algae Bloomed Surface Water

Catalysts ◽  
2020 ◽  
Vol 10 (4) ◽  
pp. 452 ◽  
Author(s):  
Sayed Mukit Hossain ◽  
Heeju Park ◽  
Hui-Ju Kang ◽  
Jong Beom Kim ◽  
Leonard Tijing ◽  
...  
Keyword(s):  
Removal Rate ◽  
Anatase Phase ◽  
Oxygen Demand ◽  
Xrd Analysis ◽  
Anatase Tio2 ◽  
X Ray Diffraction ◽  
X Ray ◽  
Uv Irradiance ◽  
Mixed Mortar

The purpose of the study was to effectively treat algae bloomed water while using a Ti-based coagulant (TiCl4) and recover photoactive novel anatase TiO2 from the flocculated sludge. Conventional jar tests were conducted in order to evaluate the coagulation efficiency, and TiCl4 was found superior compared to commercially available poly aluminum chloride (PAC). At a dose of 0.3 g Ti/L, the removal rate of turbidity, chemical oxygen demand (COD), and total phosphorus (TP) were measured as 99.8%, 66.7%, and 96.9%, respectively. Besides, TiO2 nanoparticles (NPs) were recovered from the flocculated sludge and scanning electron microscope (SEM), energy dispersive X-ray spectroscope (EDX), and X-ray diffraction (XRD) analysis confirmed the presence of only anatase phase. The recovered TiO2 was found to be effective in removing gaseous CH3CHO and NOx under UV-A lamp at a light intensity of 10 W/m2. Additionally, the TiO2 mixed mortar blocks that were prepared in this study successfully removed atmospheric nitrogen oxide (NOx) under UV irradiance. This study is one of the first to prepare anatase TiO2 from flocculated algal sludge and it showed promising results. Further research on this novel TiO2 concerning internal chemical bonds and shift in the absorbance spectrum could explore several practical implications.

scholarly journals Preparation and Characterization of Cetyl Trimethylammonium Intercalated Sericite

2014 ◽  
Vol 2014 ◽  
pp. 1-8 ◽  
Author(s):  
Hao Ding ◽  
Yuebo Wang ◽  
Yu Liang ◽  
Faxiang Qin
Keyword(s):  
Ion Exchange ◽  
Interlayer Space ◽  
Xrd Analysis ◽  
Acid Activation ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Ft Ir ◽  
Ft Ir Spectroscopy

Intercalated sericite was prepared by intercalation of cetyl trimethylammonium bromide (CTAB) into activated sericite through ion exchange with the following two steps: the activation of sericite by thermal modification, acid activation and sodium modification; the ion exchange intercalation of CTA+into activated sericite. Effects of reaction time, reaction temperature, CTAB quantity, kinds of medium, and aqueous pH on the intercalation of activated sericite were examined by X-ray diffraction (XRD) analysis, Fourier transform infrared (FT-IR) spectroscopy, differential scanning calorimetry (DSC), and thermogravimetric analysis (TGA). The results indicated that the CTA+entered sericite interlayers and anchored in the aluminosilicate interlayers through strong electrostatic attraction. The arrangement of CTA+in sericite interlayers was that alkyl chain of CTA+mainly tilted at an angle about 60° (paraffin-type bilayer) and 38° (paraffin-type monolayer) with aluminosilicate layers. The largest interlayer space was enlarged from 0.9 nm to 5.2 nm. The intercalated sericite could be used as an excellent layer silicate to prepare clay-polymer nanocomposites.

Synthesis, Different Characterizations and Pigment Application of Nanoceramic Zirconate Powder

2021 ◽  
Vol 21 (4) ◽  
pp. 2212-2220
Author(s):  
T. S. Gokul Raja ◽  
S. Balamurugan ◽  
A. Reshma
Keyword(s):  
Near Infrared ◽  
Pyrochlore Phase ◽  
Pyrochlore Structure ◽  
Nir Spectroscopy ◽  
Xrd Analysis ◽  
X Ray Diffraction ◽  
X Ray ◽  
Ft Ir ◽  
Ir Analysis ◽  
Highly Uniform

In this work, several attempts were made to prepare nanoceramic zirconate (Nd2Zr2O7) powder for pigment applications. The single pyrochlore phase, Nd2Zr2O7 was successfully synthesized with the aid of flux at relatively low temperature (1000 °C) upon milling the reaction mixture made from Nd2O3 and ZrO2 in a tungsten carbide vial. Several characterizations were done on the thermal analysis (TG/DTA), X-ray diffraction (XRD), High-resolution scanning electron microscope (HRSEM), energy dispersive X-ray (EDX) analysis, Fourier-transform infrared (FT-IR) analysis, and near-infrared (NIR spectroscopy). A single-phase nanocrystalline (˜28 nm) pyrochlore structure (Fd3m) was confirmed through XRD analysis. A highly uniform particle in the size of ˜110 nm was observed for the Nd2Zr2O7 phase in the microimages. The vibrational (FT-IR) peaks at 423 cm-1 and 510 cm-1 in FTIR spectroscopic study confirmed the formation of pyrochlore structure. Higher NIR reflectivity recorded for this material in the 750–2500 nm region shows its novel application in color cool pigments for energy-saving paints reminiscent of Bi2−xYxCe2O7, Bi2Ce2−xTbxO7, and Gd2Ti2O7.

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