scholarly journals Effects of Formulated Nano-Urea Hydroxyapatite Slow Release Fertilizer Composite on the Physical, Chemical Properties, Growth and Yield of Cyamopsis tetragonoloba (Cluster Beans)

2020 ◽  
Vol 33 (1) ◽  
pp. 159-165
Author(s):  
Shylaja Singam ◽  
Anand Rao Mesineni ◽  
Ch. Shilpa Chakra
Keyword(s):  
High Surface ◽  
High Surface Area ◽  
Chemical Properties ◽  
Growth And Yield ◽  
Precipitation Method ◽  
Cyamopsis Tetragonoloba ◽  
X Ray ◽  
Bean Plants ◽  
Co Precipitation ◽  
The Impact

Urea and phosphorous fertilizers are commonly used in agriculture but, due to their solubility in water and transportation, cause eutrophication. Hence, it is thought worthwhile to investigate for urea hydroxyapatite nanoparticles which have less mobility and could supply required N and P macronutrients to the crops. These high surface area nanoparticles are synthesized through chemical co-precipitation method and it is assumed that due to their biocompatibility, act as rich phosphorous and nitrogen source. These are characterized by powder X-ray diffraction (PXRD), dynamic light scattering (DLS), scanning electron microscope (SEM), energy dispersive X-ray analysis (EDX) and Fourier transform infrared (FT-IR). The impact of urea hydroxyapatite nanofertilizer on growth and yield of cluster bean plants for the period of four months has been carried out. The experimental results have shown that the usage of these nanofertilizers have enhanced both the plant growth and yield. The application of urea hydroxyapatite nanocomposites for the bio-availability of plants considered to be environment friendly.

Preparation of High Surface Area Ni-SDC Cermets Using a Surfactant-Assisted Co-Precipitation Method

2006 ◽  
Vol 942 ◽  
Author(s):  
Sang Joon Park ◽  
Tae Wook Eom ◽  
Jae Eun Oh ◽  
Hae Kwang Yang ◽  
Kyung Hwan Kim
Keyword(s):  
Surface Area ◽  
Cetyltrimethylammonium Bromide ◽  
High Surface ◽  
High Surface Area ◽  
Precipitation Method ◽  
X Ray Diffraction ◽  
X Ray ◽  
Two Phases ◽  
Co Precipitation ◽  
Surfactant Assisted

ABSTRACTA surfactant-assisted co-precipitation method was employed for obtaining high surface area Ni-SDC with improved structural properties for SOFC applications. In the work, a cationic surfactant, cetyltrimethylammonium bromide(CTAB) was employed with NiCl2, SmCl3 and CeCl3 as precursors and NH4OH as mineralizer. The elimination of surfactants upon calcination gives rise to the formation of high surface area NiO-SDC. When calcined at 600°C, the powders with surface area of 249 m2/g, were obtained and the pore size was 14.45 nm. The powders consist of two phases, the cubic NiO and SDC confirmed with X-ray diffraction identification.

scholarly journals Lanthanum based high surface area perovskite-type oxide and application in CO and propane combustion

2018 ◽  
Vol 34 (1) ◽  
pp. 31
Author(s):  
Paulo Roberto Nagipe Da Silva ◽  
Ana Brígida Soares
Keyword(s):  
Catalytic Activity ◽  
Photoelectron Spectroscopy ◽  
Perovskite Phase ◽  
High Surface ◽  
High Surface Area ◽  
Propane Combustion ◽  
Total Oxidation ◽  
X Ray ◽  
Co Precipitation ◽  
Perovskite Type

The perovskite-type oxides using transition metals present a promising potential as catalysts in total oxidation reaction. The present work investigates the effect of synthesis by oxidant co-precipitation on the catalytic activity of perovskite-type oxides LaBO3 (B= Co, Ni, Mn) in total oxidation of propane and CO. The perovskite-type oxides were characterized by means of X-ray diffraction, nitrogen adsorption (BET method), thermo gravimetric and differential thermal analysis (ATG-DTA) and X-ray photoelectron spectroscopy (XPS). Through a method involving the oxidant co-precipitation it’s possible to obtain catalysts with different BET surface areas, of 33-44 m2/g, according the salts of metal used. The characterization results proved that catalysts have a perovskite phase as well as lanthanum oxide, except LaMnO3, that presents a cationic vacancies and generation for known oxygen excess. The results of catalytic test showed that all oxides have a specific catalytic activity for total oxidation of CO and propane even though the temperatures for total conversion change for each transition metal and substance to be oxidized.

scholarly journals Nanocellulose: Resources, Physio-Chemical Properties, Current Uses and Future Applications

2021 ◽  
Vol 3 ◽  
Author(s):  
Prabhpreet Kaur ◽  
Neha Sharma ◽  
Meghana Munagala ◽  
Rangam Rajkhowa ◽  
Ben Aallardyce ◽  
...  
Keyword(s):  
Energy Use ◽  
High Surface ◽  
High Surface Area ◽  
Chemical Properties ◽  
Value Added ◽  
Processing Technique ◽  
Future Research ◽  
Wide Range ◽  
Systems View ◽  
The Impact

The growing environmental concerns due to the excessive use of non-renewable petroleum based products have raised interest for the sustainable synthesis of bio-based value added products and chemicals. Recently, nanocellulose has attracted wide attention because of its unique properties such as high surface area, tunable surface chemistry, excellent mechanical strength, biodegradability and renewable nature. It serves wide range of applications in paper making, biosensor, hydrogel and aerogel synthesis, water purification, biomedical industry and food industry. Variations in selection of source, processing technique and subsequent chemical modifications influence the size, morphology, and other characteristics of nanocellulose and ultimately their area of application. The current review is focused on extraction/synthesis of nanocellulose from different sources such as bacteria and lignocellulosic biomass, by using various production techniques ranging from traditional harsh chemicals to green methods. Further, the challenges in nanocellulose production, physio-chemical properties and applications are discussed with future opportunities. Finally, the sustainability of nanocellulose product as well as processes is reviewed by taking a systems view. The impact of chemicals, energy use, and waste generated can often negate the benefit of a bio-based product. These issues are evaluated and future research needs are identified.

scholarly journals Cu K-edge XANES: polymer, organic, inorganic spectra, and experimental considerations

2017 ◽  
Vol 32 (S2) ◽  
pp. S28-S32 ◽  
Author(s):  
Mikael Larsson ◽  
Johan B. Lindén ◽  
Simarpreet Kaur ◽  
Brock Le Cerf ◽  
Ivan Kempson
Keyword(s):  
Thin Films ◽  
Design Of Experiments ◽  
High Surface ◽  
High Surface Area ◽  
Polymer Nanoparticles ◽  
Valuable Resource ◽  
X Ray ◽  
The Impact ◽  
X Ray Absorption ◽  
Beam Damage

In pursuit of design and characterisation of Cu adsorbing in thin films, we present data from a large variety of Cu-K edge X-ray Absorption Near Edge Spectroscopy (XANES) spectra obtained from organic and inorganic standards. Additionally, we have explored the impact of beam damage inducing redox alterations. Polymer nanoparticles were tested against films to produce higher concentration samples while maintaining high surface area to bulk effects. Spectra from nanoparticles were highly comparable to thin films of ~8 nm thickness, implying comparable contributions by surface effects on copper association. Finally, we observed no impact on Cu XANES spectra from vitrification with dimethyl sulfoxide to produce amorphous frozen, hydrated samples. The spectra should act as a valuable resource in assisting the design of experiments and identification of copper associations.

Facile preparation of a Ni/MgAl2O4 catalyst with high surface area: enhancement in activity and stability for CO methanation

2018 ◽  
Vol 41 (3-4) ◽  
pp. 73-89 ◽  
Author(s):  
Shengjia Wang ◽  
Zhiwei Tian ◽  
Qing Liu ◽  
Yingyun Qiao ◽  
Yuanyu Tian
Keyword(s):  
Carbon Black ◽  
Surface Area ◽  
High Surface ◽  
High Surface Area ◽  
Catalytic Performance ◽  
Precipitation Method ◽  
Co Methanation ◽  
Co Precipitation ◽  
Spinel Catalysts ◽  
Nickel Species

Abstract To enhance the performance of anti-coking and anti-sintering of the Ni-based catalysts during the reaction process of CO methanation, we synthesized a group of catalysts denoted as “Ni-xMgAl2O4” via the modified co-precipitation method utilizing carbon black as hard template. The addition of carbon black could significantly improve the specific surface area of MgAl2O4 to 235.8 m2 g−1. The Ni catalysts supported on high-surface-area MgAl2O4 (Ni-0.25MA) exhibited enhanced catalytic performance and hydrothermal stability in comparison with the conventional Ni-based magnesia alumina spinel catalysts with the same NiO content. In the process of 120-h stability test, the Ni-0.25MA catalyst exhibited remarkable improvement in both anti-sintering and anti-coking. After a series of characterizations, we found that the addition of carbon black could make more pores over MgAl2O4, resulting in the supported Ni particles being anchored in the pore rather than on the outside surface of support. This structure enhanced the dispersion of nickel nanoparticles, thus strengthening the interaction between nickel species and the MgAl2O4 support, which led to the promotion in catalytic activity and stability of high-surface-area Ni/MgAl2O4.

Physicochemical Characterization of Natural Diatomite from Lampang Province, Thailand as a Solid Catalyst

2020 ◽  
Vol 861 ◽  
pp. 371-377
Author(s):  
Wilasinee Kingkam ◽  
Sasikarn Nuchdang ◽  
Pipat Laowattanabandit ◽  
Dussadee Rattanaphra
Keyword(s):  
Pore Size ◽  
Surface Area ◽  
Calcination Temperature ◽  
High Surface ◽  
High Surface Area ◽  
Physicochemical Characterization ◽  
Chemical Properties ◽  
Biodiesel Production ◽  
Solid Catalyst ◽  
X Ray

This paper presents the studies on physical and chemical properties of the natural diatomite originating from Mae Tha District, Lampang the northern of Thailand as solid catalyst. The diatomite was characterized by X-ray diffraction (XRD), X-ray fluorescence (XRF) and nitrogen adsorption-desorption isotherm. The effect of calcination temperature on chemical composition, cyrytalline phase and textural properties of diatomite was also investigated. The XRF results indicated that the diatomite was composed mostly of SiO2, K2O, CaO and MgO. The calcination temperature ranging from 300 to 900 °C had no effect on the crystalline phase of diatiomite. The high surface area and large pore size diameter of diatomite was observed when the calcination temperature was below 900 °C. All the physicochemical results show the existence of SiO2, K2O, CaO and MgO, the high surface area and pore size diameter, indicate that the diatomite could potentially be used to a solid catalyst for biodiesel production.

In Situ microscopy of the anodic etching of silicon

1995 ◽  
Vol 53 ◽  
pp. 232-233
Author(s):  
Frances M. Ross ◽  
Peter C. Searson
Keyword(s):  
Composite Structures ◽  
High Surface ◽  
High Surface Area ◽  
Chemical Properties ◽  
Selective Etching ◽  
Silicon On Insulator ◽  
Second Phase ◽  
Porous Layers ◽  
New Class ◽  
Porous Semiconductors

Porous semiconductors represent a relatively new class of materials formed by the selective etching of a single or polycrystalline substrate. Although porous silicon has received considerable attention due to its novel optical properties1, porous layers can be formed in other semiconductors such as GaAs and GaP. These materials are characterised by very high surface area and by electrical, optical and chemical properties that may differ considerably from bulk. The properties depend on the pore morphology, which can be controlled by adjusting the processing conditions and the dopant concentration. A number of novel structures can be fabricated using selective etching. For example, self-supporting membranes can be made by growing pores through a wafer, films with modulated pore structure can be fabricated by varying the applied potential during growth, composite structures can be prepared by depositing a second phase into the pores and silicon-on-insulator structures can be formed by oxidising a buried porous layer. In all these applications the ability to grow nanostructures controllably is critical.

scholarly journals Non-Thermal Plasma-Modified Ru-Sn-Ti Catalyst for Chlorinated Volatile Organic Compound Degradation

Catalysts ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 1456
Author(s):  
Yujie Fu ◽  
You Zhang ◽  
Qi Xin ◽  
Zhong Zheng ◽  
Yu Zhang ◽  
...  
Keyword(s):  
Plasma Treatment ◽  
Photoelectron Spectroscopy ◽  
High Surface ◽  
High Surface Area ◽  
Surface Oxidation ◽  
Treatment Method ◽  
X Ray ◽  
Chlorinated Volatile Organic Compounds ◽  
Volatile Organic ◽  
Doped Titania

Chlorinated volatile organic compounds (CVOCs) are vital environmental concerns due to their low biodegradability and long-term persistence. Catalytic combustion technology is one of the more commonly used technologies for the treatment of CVOCs. Catalysts with high low-temperature activity, superior selectivity of non-toxic products, and resistance to chlorine poisoning are desirable. Here we adopted a plasma treatment method to synthesize a tin-doped titania loaded with ruthenium dioxide (RuO2) catalyst, possessing enhanced activity (T90%, the temperature at which 90% of dichloromethane (DCM) is decomposed, is 262 °C) compared to the catalyst prepared by the conventional calcination method. As revealed by transmission electron microscopy, X-ray diffraction, N2 adsorption, X-ray photoelectron spectroscopy, and hydrogen temperature-programmed reduction, the high surface area of the tin-doped titania catalyst and the enhanced dispersion and surface oxidation of RuO2 induced by plasma treatment were found to be the main factors determining excellent catalytic activities.

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