scholarly journals Bio-Mediated Soil Improvement Using Plant Derived Enzyme in Addition to Magnesium Ion

Crystals ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 516
Author(s):  
Md Al Imran ◽  
Kazunori Nakashima ◽  
Satoru Kawasaki
Keyword(s):  
Unconfined Compressive Strength ◽  
Xrd Analysis ◽  
Soil Improvement ◽  
Magnesium Ion ◽  
Carbonate Precipitation ◽  
X Ray Diffraction ◽  
X Ray ◽  
Molar Ratios ◽  
Sand Particles ◽  
Lower Molar

Recently, soil improvement using EICP (Enzyme-Induced Carbonate Precipitation) methods in the geotechnical and geo-environmental field has become a prominent interest worldwide. The objective of this study was to develop an improved extraction technique of crude urease from watermelon seeds in both dry and germinated conditions. Subsequently, this study also analyzed the improvement methodology of crystal polymorphs and soil bonding incorporation of various Mg2+/Ca2+ ratios. The optimization of enzyme-mediated carbonate precipitation was also investigated by Scanning Electron Microscope (SEM) and X-ray Diffraction (XRD) analysis. Results confirmed that the precipitated crystals are mainly calcite, vaterite and aragonite primarily (depending on the Mg2+/Ca2+ ratios). Therefore, to improve the bonding capacity in between the sand particles a novel improvement methodology was investigated by adding various Mg2+/Ca2+ ratios. The mechanical properties of the treated soil (Mikawa Sand, D50 = 0.870 mm) specimens were tested by unconfined compressive strength (UCS) and this confirmed the effectiveness of adding various Mg2+/Ca2+ ratios. The results of the UCS tests showed that, the lower molar ratios of Mg2+/Ca2+ can significantly improve the UCS of the specimen (up to 50%) which could be considered a significant outcome for different bio-geotechnical applications.

Parascholzite Coatings on Niobium Substrates

2011 ◽  
Vol 493-494 ◽  
pp. 477-482
Author(s):  
Felipe Nobre Moura ◽  
Luis Henrique Leme Louro ◽  
Luciano Andrade Gobbo ◽  
Marcelo Henrique Prado da Silva
Keyword(s):  
Hydrothermal Process ◽  
Xrd Analysis ◽  
X Ray Diffraction ◽  
X Ray ◽  
Molar Ratios ◽  
Phosphate Coatings ◽  
Calcium Phosphate Coatings ◽  
Titanium Substrates ◽  
New Phase ◽  
Scanning Electron

This study proposes a hydrothermal process to produce monetite and zinc-doped calcium phosphate coatings with different (Ca+Zn)/P molar ratios, in an attempt to incorporate zinc benefits on bone formation to hydroxyapatite precursors. The method consists of coating niobium and titanium substrates in an aqueous solution rich in (PO4)3-and calcium (Ca)2+ions under specific conditions (pH ≡ 3.7, 80°C). Scanning electron microscopy (SEM) and X-ray diffraction (XRD) analyses were performed to characterize the coatings. From XRD analysis, we concluded that substitution of Ca by Zn was feasible up to 15% mol Zn, and the new phase obtained was parascholzite (JCPDS-01-086-2372).

scholarly journals Effect of Three Bioenzymes on Compaction, Consistency Limits, and Strength Characteristics of a Sedimentary Residual Soil

2015 ◽  
Vol 2015 ◽  
pp. 1-9 ◽  
Author(s):  
Tanveer Ahmed Khan ◽  
Mohd Raihan Taha
Keyword(s):  
Compressive Strength ◽  
Unconfined Compressive Strength ◽  
Soil Improvement ◽  
Soil Samples ◽  
Atterberg Limits ◽  
Residual Soil ◽  
X Ray Diffraction ◽  
Compaction Characteristics ◽  
X Ray ◽  
Curing Period

Bioenzymes are organic degradable materials, currently introduced as soil improvement additives. In this experimental study, three types of bioenzymes from three different countries were used to improve Universiti Kebangsaan Malaysia (UKM) soil. UKM soil has properties quite similar to soils recommended as suitable by bioenzyme suppliers. The effect of the three bioenzymes on Atterberg limits, compaction characteristics, and unconfined compressive strength was studied. Controlled untreated and treated samples for two dosages at curing times up to three months were prepared and tested after completion of the curing period. Some results showed little improvement in compaction characteristics, and unconfined compressive strength, but no notable improvement was noticed in Atterberg limits. X-ray diffraction (XRD), X-ray fluorescence (XRF), and field emission scanning electron microscopy (FESEM) tests were conducted for untreated and treated soil samples after two months of curing. XRD and XRF did not show any change in mineralogy and chemical composition between controlled untreated samples and samples treated with the three bioenzymes. However, the FESEM images revealed a denser packing of particles for soil samples treated with two of the bioenzymes.

A Simple Microwave Route for the Synthesis of Tricalcium Phosphate (β-TCP) Powders for Bone Healing Applications

2017 ◽  
Vol 894 ◽  
pp. 14-16
Author(s):  
Nida Iqbal ◽  
M.R. Abdul Kadir
Keyword(s):  
Tricalcium Phosphate ◽  
Xrd Analysis ◽  
Biological Properties ◽  
X Ray Diffraction ◽  
X Ray ◽  
Molar Ratios ◽  
Defect Site ◽  
Ft Ir ◽  
Xrd Patterns ◽  
Tricalcium Phosphates

The recent trend in bioceramics research is mainly concentrated on bioactive ceramics, i.e. hydroxyapatite, tricalcium phosphates and bioactive glasses, as they exhibit superior biological properties over other materials. Among these tricalcium phosphates have been found very important member due to their biocompatible and biodegradable properties that can help to promote new bone formation when implanted in a bone defect site. Therefore the aimed of the present work was to investigate the synthesis of tricalcium phosphate via simple microwave route at Ca/P molar ratios below, 1.67 and at pH of reaction environment equal 5. The detail characterizations of the prepared samples were carried out using Energy-dispersive X-ray spectroscopy (EDX), FT-IR spectroscopy (FTIR) and X-Ray Diffraction (XRD) analysis. From the analysis of EDX, FTIR and XRD patterns, the formation of β-TCP was confirmed.

scholarly journals Pengaruh medan magnet pada presipitasi CaCO3 untuk pencegahan pembentukan kerak

2018 ◽  
Vol 5 (2) ◽  
pp. 401
Author(s):  
Nelson Laksono ◽  
Setijo Bismo ◽  
Elsa Kristanti ◽  
Roekmijati Widaningrum
Keyword(s):  
Magnetic Fields ◽  
Formation Rate ◽  
Hard Water ◽  
Xrd Analysis ◽  
Carbonate Precipitation ◽  
X Ray Diffraction ◽  
Calcium Carbonate Precipitation ◽  
X Ray ◽  
Quantitative Results ◽  
Cacl2 Solution

Hard water magnetizing is applied as physical water treatment for reducing the formation of scale (CaCO3) in piping equipment and boiler Na2 CO3 and CaCl2 solution had been used as sample of hard water in many researches to investigate the influence of magnetic fields on CaCO3 formation. Na2 CO3 solution had been magnetized first before it was mixed with CaCl2 solution. By changing the strength of magnetic fields, exposed time, precipitated time, and temperature of sample, this study presents quantitative results of total scale deposit, total precipitated CaC03 and morphology of the deposits. This research was run by comparing magnetically and non-magnetically-treated samples. The results showed a decrease of deposits formation rate and total amount of precipitated CaCO3 of magnetically-treated samples. An increase in precipitation temperature increased the total amount of precipitated CaCO3 and the maximum precipitation was achieved at the 50°C. Microscope images showed that a smaller amount but larger size of CaCO3 particles formed in magnetically-treated samples. X-ray diffraction (XRD) analysis showed that samples contain mostly calcite. This research's result showed that magnetization of Na2 CO3 solution could reduce formation rate of CaCO3 either in solution or in the surface of hard water.Keywords: Magnetic Treatment, Hard Water; Calcium Carbonate Precipitation; CaCO3 Deposit Morphology AbstrakMagnetisasi air sadah merupakan proses fisik yang bertujuan menekan terbentuknya kerak (CaCO3) pada sistem perpipaan dan boiler. Campuran larutan Na2 CO3 dan CaCl2 banyak digunakan sebagai model air sadah sintetik guna mengamati pengaruh medan magnet terhadap pembentukan CaCO3 dalam air sadah. Larutan Na2 CO3 dimagnetisasi terlebih dahulu sebelum dicampur dengan larutan CaCl2 Variabel proses meliputi waktu magnetisasi, waktu presipitasi, kuat medan, dan suhu larutan sampel sementara parameter yang akan diamati adalah jumlah deposit CaCO3 jumlah presipitasi total CaCO3 dan morfologi deposit CaCO3. Perbandingan parameter pengamatan dilakukan terhadap sampel yang dimagnetisasi dan sampel non-magnetisasi. Hasil percobaan menunjukkan adanya penurunan pembentukan deposit dan presipitasi total CaCO3 pada sampel yang dimagnetisasi dibanding sampel non-magnetisasi.   Peningkatan suhu presipitasi CaCO3 meningkatkan jumlah presipitasi total CaCO3 dan harga maksimum deposit CaCO3 yang terbentuk dicapai pada suhu 50°C. Hasil foto mikroskop menunjukkan jumlah partikel CaCO3 yang terbentuk pada sampel yang dimagnetisasi lebih sedikit dan ukuran partikelnya lebih besar dibanding sampel non-magnetisasi. Hasil uji XRD menunjukkan hanya kristal kalsit yang dominan pada kedua jenis sampel. Hasil penelitian ini menunjukkan bahwa magnetisasi larutan Na2 CO3 dapat menahan laju pembentukan CaCO3 dilarutan maupun dipermukaan pada air sadah.Kata Kunci: Perlakuan Magnetik, Air Sadah, Presipitasi Kalsium Karbonat, Morfologi Deposit CaCO3

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.

scholarly journals Photocatalytic Reduction of CO2 to Methanol Using a Copper-Zirconia Imidazolate Framework

Catalysts ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 346
Author(s):  
Sonam Goyal ◽  
Maizatul Shima Shaharun ◽  
Ganaga Suriya Jayabal ◽  
Chong Fai Kait ◽  
Bawadi Abdullah ◽  
...  
Keyword(s):  
Photoelectron Spectroscopy ◽  
Catalyst Support ◽  
Oxidation Potential ◽  
Molar Ratio ◽  
X Ray Diffraction ◽  
X Ray ◽  
Molar Ratios ◽  
Optimum Parameters ◽  
Reduction Of Co2 ◽  
Enhanced Yield

A set of novel photocatalysts, i.e., copper-zirconia imidazolate (CuZrIm) frameworks, were synthesized using different zirconia molar ratios (i.e., 0.5, 1, and 1.5 mmol). The photoreduction process of CO2 to methanol in a continuous-flow stirred photoreactor at pressure and temperature of 1 atm and 25 °C, respectively, was studied. The physicochemical properties of the synthesized catalysts were studied using X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and photoluminescence (PL) spectroscopy. The highest methanol activity of 818.59 µmol/L.g was recorded when the CuZrIm1 catalyst with Cu/Zr/Im/NH4OH molar ratio of 2:1:4:2 (mmol/mmol/mmol/M) was employed. The enhanced yield is attributed to the presence of Cu2+ oxidation state and the uniformly dispersed active metals. The response surface methodology (RSM) was used to optimize the reaction parameters. The predicted results agreed well with the experimental ones with the correlation coefficient (R2) of 0.99. The optimization results showed that the highest methanol activity of 1054 µmol/L.g was recorded when the optimum parameters were employed, i.e., stirring rate (540 rpm), intensity of light (275 W/m2) and photocatalyst loading (1.3 g/L). The redox potential value for the CuZrIm1 shows that the reduction potential is −1.70 V and the oxidation potential is +1.28 V for the photoreduction of CO2 to methanol. The current work has established the potential utilization of the imidazolate framework as catalyst support for the photoreduction of CO2 to methanol.

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.

scholarly journals An Insight into Chemistry and Structure of Colloidal 2D-WS2 Nanoflakes: Combined XPS and XRD Study

Nanomaterials ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 1969
Author(s):  
Riccardo Scarfiello ◽  
Elisabetta Mazzotta ◽  
Davide Altamura ◽  
Concetta Nobile ◽  
Rosanna Mastria ◽  
...  
Keyword(s):  
Photoelectron Spectroscopy ◽  
Xrd Analysis ◽  
Crystal Habit ◽  
Phase Identification ◽  
X Ray Diffraction ◽  
X Ray ◽  
Morphological Evaluation ◽  
Rational Understanding ◽  
Structural Inspection

The surface and structural characterization techniques of three atom-thick bi-dimensional 2D-WS2 colloidal nanocrystals cross the limit of bulk investigation, offering the possibility of simultaneous phase identification, structural-to-morphological evaluation, and surface chemical description. In the present study, we report a rational understanding based on X-ray photoelectron spectroscopy (XPS) and structural inspection of two kinds of dimensionally controllable 2D-WS2 colloidal nanoflakes (NFLs) generated with a surfactant assisted non-hydrolytic route. The qualitative and quantitative determination of 1T’ and 2H phases based on W 4f XPS signal components, together with the presence of two kinds of sulfur ions, S22− and S2−, based on S 2p signal and related to the formation of WS2 and WOxSy in a mixed oxygen-sulfur environment, are carefully reported and discussed for both nanocrystals breeds. The XPS results are used as an input for detailed X-ray Diffraction (XRD) analysis allowing for a clear discrimination of NFLs crystal habit, and an estimation of the exact number of atomic monolayers composing the 2D-WS2 nanocrystalline samples.

scholarly journals Effect of Molybdenum Content on the Corrosion and Microstructure of Low-Ni, Co-Free Maraging Steels

Metals ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 852
Author(s):  
Asiful H. Seikh ◽  
Hossam Halfa ◽  
Mahmoud S. Soliman
Keyword(s):  
Corrosion Resistance ◽  
Electrochemical Impedance ◽  
Microstructural Analysis ◽  
Xrd Analysis ◽  
X Ray Diffraction ◽  
Alloying Element ◽  
X Ray ◽  
Maraging Steels ◽  
Eds Analysis ◽  
Electroslag Refining

Molybdenum (Mo) is an important alloying element in maraging steels. In this study, we altered the Mo concentration during the production of four cobalt-free maraging steels using an electroslag refining process. The microstructure of the four forged maraging steels was evaluated to examine phase contents by optical microscopy, scanning electron microscopy (SEM), and X-ray diffraction (XRD) analysis. Additionally, we assessed the corrosion resistance of the newly developed alloys in 3.5% NaCl solution and 1 M H2SO4 solution through potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) techniques. Furthermore, we performed SEM and energy-dispersive spectroscopy (EDS) analysis after corrosion to assess changes in microstructure and Raman spectroscopy to identify the presence of phases on the electrode surface. The microstructural analysis shows that the formation of retained austenite increases with increasing Mo concentrations. It is found from corrosion study that increasing Mo concentration up to 4.6% increased the corrosion resistance of the steel. However, further increase in Mo concentration reduces the corrosion resistance.

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