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Elemental analysis of these medicinal plants was performed by employing Instrumental Neutron Activation Analysis (INAA) and Atomic Absorption Spectroscopy (AAS) techniques. The samples were irradiated with thermal neutrons in a nuclear reactor and the induced radio activity was counted by gamma ray spectrometry using an efficiency calibrated high resolution High Purity Germanium (HPGe) detector. Most of the medicinal plants were found to be rich in one or more of the elements under study. The variation in elemental concentration in same medicinal plant samples collected from different regions was studied and the biological effects of these elements on human beings are discussed. The study was also extended further to estimate the level of toxic elements like Cr, Cd, Ni, Pb and Hg in medicinal plants which arises due to environmental pollution. The results were discussed with careful reference to established role of essential and rare elements to the physiology and pathology of plant and human life.

Nutritional and medicinal properties of black sesame seeds (Sesamum indicum) make it very valuable in traditional system of food. Minerals in Sesamum indicum play an important role to enhance its nutritional value. The present research comprises on proximate and chemical analysis of Sesamum indicum. This study is also based on the development of ashing methods for extraction of metals in black sesame seeds. The paper aims to discuss these issues.

Black sesame seeds were taken from local market at Karachi-Pakistan. Proximate analysis of seeds comprises of moisture content, ash content and total metal content by EDTA titration. Digestion of this herb was done in different medium, i.e. HNO₃, HCl, H₂SO₄ and simple ash (ash was prepared without using any acid). Atomic absorption spectroscopy was used for the analysis of metals, i.e. Fe, Zn, Cu and Mg in all these ashes.

From the results it is concluded that best medium for ashing is H₂SO₄, by which maximum ash (5.39±0.0021 per cent) produced. Qualitative analysis (based on Ksp values) also confirmed the presence of maximum number of metals in H₂SO₄ medium. Complexometric titration also revealed that maximum metal content was found to be in HCl and H₂SO₄ ash. Results from atomic absorption spectroscopy revealed that H₂SO₄ is the best method for copper (0.399±0.0001 mg/g) and iron (0.3993±0.0015 mg/g), while simple ash can extract zinc and magnesium at their maximum level.

This research demonstrates the best ashing method for the extraction of micronutrients, present in Sesamum indicum. These micronutrients are very beneficial for human health.

The purpose of this paper is to investigate the surface corrosion products of copper alloys by non‐destructive techniques (NDT) and correlate them with their bulk composition.

Specimens of copper alloys, whose compositions were close to those of ancient copper‐based artefacts, were left to be corroded in simulated soil solution containing ammoniacal buffering solution of pH =10 in 1:1 ratio, in order to accelerate the corrosion rate. The elemental compositions of the surface corrosion products were determined versus time using X‐Ray Fluorescence Spectroscopy, and the surface morphology by Scanning Electron Microscopy with Energy Dispersive X‐Ray Micro‐detector methods, and the results were compared to the bulk composition, as measured by Atomic Absorption Spectroscopy and Inductively Coupled Plasma Atomic Emission Spectroscopy.

During the corrosion evolution of the copper alloys in the corrosive solution, transitional phenomena were observed such as an initial decrease of the copper concentration with a simultaneous increase of the concentrations of the secondary alloying metals (Sn, Zn and Pb). After 30‐60 immersion days, the alloy concentrations were stabilised.

The results of this research could contribute to the non‐destructive characterisation of copper‐based ancient artefacts (from which the taking of samples is not allowed).

The commercial stainless steels have been used extensively in the biomedicine application and their electrochemical behaviour in the simulated body fluid (SBF) are not uncovered obviously. In this research, the corrosion resistance of the commercial stainless steel of Fe–17Cr–xNi alloys (x = 4, 8, 10 and 14) has been studied. This study aims to evaluate the rate of corrosion and corrosion resistance of some Fe–Cr–Ni alloys in SBF at 37°C.

In this research, the corrosion resistance of the commercial stainless steel of Fe–17Cr–xNi alloys has been studied using open circuit potential, electrochemical impedance spectroscopy and potentiodynamic polarization in the SBF at 37°C and pH 7.4 for a week. Also, the surface morphology of the four alloys was investigated using scanning electron microscopy, elemental composition was obtained via energy dispersive spectroscopy and the crystal lattice structure of Fe–17Cr–xNi alloys was obtained using X-ray diffraction technique. The chemical structure of the protective oxide film has been examined by X-ray photoelectron spectroscopy (XPS) and metals ions released into the solution have been detected after different immersion time using atomic absorption spectroscopy.

The results revealed that the increase of the Ni content leads to the formation of the stable protective film on the alloys such as the Fe–17Cr–10Ni and Fe–17Cr–14Ni alloys which possess solid solution properties. The Fe–17Cr–14Ni alloy displayed highest resistance of corrosion, notable resistance for localized corrosion and the low corrosion rate in SBF because of the formation of a homogenously protective oxide film on the surface. The XPS analysis showed that the elemental Fe, Cr and Ni react with the electrolyte medium and the passive film is mainly composed of Cr₂O₃ with some amounts of Fe(II) hydroxide at pH 7.4.

This work includes important investigation to use commercial stainless steel alloys for biomedical application.

In aqueous alkaline ink media aluminium pigments react with the evolution of hydrogen, whereas the more noble copper and brass pigments react by the absorption of oxygen, which can be measured gas‐volumetrically. These different corrosion reactions can be inhibited with addition of certain binders for printing inks, such as styrene‐maleic acid resins, maleic resins and to some extent styrene‐acrylate resins. So, certain ink resins inhibit corrosion reactions of different noble metal pigments in a reducing hydrogen atmosphere (aluminium) as well as in an oxidizing oxygen atmosphere (copper and brass). The overall best resin is that with the lowest acid number. Atomic absorption spectroscopy measurements showed that a lower acid number pruduces a lower solubility of copper and zinc in the medium.

The innovation process is not homogeneous, but highly variable according to industrial sector and the level of abstraction of the innovation itself. This level of abstraction from existing products while not precisely measurable, can be graded, thus giving some guidance as to the probability of success according to the size of investment and the risk involved. The complexity of the new product and its technological level (the monograph confines the argument to product innovation) will also determine how the innovating organisation handles the innovation. Much research has now been done into the innovation process, and some of the leading projects and their findings are analysed. Supporting the basic argument there are two case histories, one of a successful scientific instrument, together with reference to an unsuccessful attempt to launch it, and one of a failure with a new material, in spite of highly successful technology.

The purpose of this paper is to investigate the inhibitive performance of Coreopsis tinctoria (C. tinctoria) plant extract for the corrosion of mild steel in 0.5 M H₂SO₄.

The inhibition efficiency was studied by weight loss, electrochemical measurements and the surface analysis was done by Raman, scanning electron microscopy/energy-dispersive X-ray spectroscopy (SEM-EDS) and atomic absorption spectroscopy (AAS) analysis.

Maximum inhibition efficiency of C. tinctoria in 0.5 M H₂SO₄ on mild steel is 80.62 per cent (500 ppm) at 303 ± 1K. The adsorption of the C. tinctoria on the mild steel surface in 0.5 M H₂SO₄ was found to obey Langmuir adsorption isotherm. Temperature studies were carried out and the significant parameters, such as change in enthalpy (ΔH^°), change in entropy (ΔS^°) and change in free energy (ΔG°_ads) and heat of adsorption (Qads), were calculated. The productive layer formed on the mild steel surface in 0.5 M H₂SO₄ were confirmed by the Raman spectral analysis.

This paper provides information on the inhibitive properties of C. tinctoria plant extract which is found to be a good corrosion inhibitor for mild steel in 0.5 M H₂SO₄.

The purpose of this paper (in vitro) study was to determine the effect of pH of artificial saliva on the corrosion behavior of a Ni-Cr-Mo alloy at 37 ± 1°C.

The corrosion behavior of a commercially available Ni-Cr-Mo base dental alloy was studied by potentiodynamic polarization and electrochemical impedance spectroscopy techniques. The effect of pH on corrosion and Ni ion release was also investigated by scanning electron microscopy and atomic absorption spectroscopy.

The results suggested that the order of corrosion rate was: pH3 > pH5 > pH9 > pH7. Corrosion rate in pH3 was significantly different with other pH levels. Nickel depletion significantly occurred in alloy without passivation. The corrosion resistance and ion release of Ni-Cr-Mo alloys in different pH levels of artificial saliva depended on the stability of the passive layer. Acidic pH level severely corrodes Ni-Cr-Mo base metal alloys and increases Ni ion release.

This manuscript describes the relationship between corrosion rate and nickel ion release of a dental Ni-Cr-Mo base alloy as a function of saliva pH examined by electrochemical impedance spectroscopy (EIS), polarization, scanning electron microscopy and energy dispersive X-ray spectroscopy in artificial saliva. The main novelty of this work includes the material/structure/corrosion relationship in artificial saliva with different pH. This property would be very interesting for dental materials applications and clinical dentistry.

Flowers and fruits of Madhuca longifolia (Koenig) (mahua) tree are edible and used as traditional Indian medicines. The physicochemical properties of different parts of mahua are investigated. This study aims to estimate the different mineral contents, polyphenols compounds and antioxidant activities by 2,2-diphenyl-1-picrylhydrazyl inhibition, reducing power, free radical scavenging activity using 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) and ferric reducing antioxidant power assays of mahua flower, ripe and unripe fruit.

Flavonoids were identified and quantified in yellow flowers and fruits of M. longifolia tree by high-performance liquid chromatography with diode array detector. Low molecular weight carbohydrates were determined by the ICBio scan, a specific method for determining of carbohydrates. Mineral content is determined by laser-induced breakdown spectroscopy (LIBS) and atomic absorption spectroscopy. Physicochemical, nutritional and mineral properties of mahua flower, ripe and unripe fruit were investigated by the statistical approach of principal component analysis (PCA).

Ascorbic acid, gallic acid (GA), quercetin and myrcetin were the phenolic compounds identified and quantified in mahua flower and fruit extracts. Sugar profiling of mahua flowers and fruits confirmed the presence of inositol, sorbitol, mannitol, dextrose, fructose, sucrose, raffinose and maltose. The mineral content of Na, K, Mg and Ca was present in quite a good amount in all samples. Total phenolic content (TPC) was significantly high in mahua flower (25.3 ± 1.0 mg GA equivalent/g FW) followed by mahua unripe (15.8 ± 1.0 mg GA equivalent/g FW) and ripe fruit (14.3 ± 1.0 mg GA equivalent/g FW) at p = 5%. In contrast, total flavonoid contents (TFCs) were highest in ripe fruit, then mahua flower and unripe fruit. Positive correlations were predicted by PCA for mahua flower with TPC, antioxidant activity assays and minerals except for Na; ripe fruit with TFC and Na; and unripe fruit with maltose and sorbitol.

This study demonstrates the application of LIBS for the determination of elements present in the mahua flowers and fruits and reveals that mahua can be a good source of nutrients. Sugar profiling of mahua flower showed that it is a rich source of reducing and non-reducing sugar, proving that mahua flower juice can be used as a natural sweetener in the development of different food products, namely, biscuits, cookies, cake, jam, jelly, juice and squash.

The purpose of this paper was to study the parameters affecting corrosion of the closed-loop oscillating heat-pipe with check valves (CLOHP/CV) in a system in clear that will be basic data to be used in future research. The majority of research focuses on the inner surface corrosion heat-pipe systems. The CLOHP/CV is commonly favored in cooling electronic devices, etc. Despite these common applications, limited reliable experimental research findings are available on the operation of the CLOHP/CV. Because of these reasons, the lack of detailed data, working fluids effect, working temperatures and duration of testing of the CLOHP/CV, this study focuses on determining the actual inner surface corrosion.

Seven types of copper tubes used in the CLOHP/CV set were sectioned to observe their inner surfaces. Seven different specimens with tube corrosion were examined by a visual inspection, scanning electron microscopy (SEM) and energy dispersive X-ray spectrometry (EDX). The technique for detecting metals solution in samples is based on the fact that ground state metals absorb light at specific wavelengths. Metal ions in a solution are converted to atomic state by means of a flame. In this study, concentration of copper particle in the working fluid was found by flame atomic absorption spectroscopy (Flame-AAS) and elements that occurred on inner surface tube were analyzed by EDX.

The analyses with SEM and EDX testing found that the character corrosion of inner surface of CLOHP/CV was pitting clearly. The analysis with Flame-AAS found that the concentration of copper particles in the distilled water and ethanol as working fluid is more than after 1,000 hours until 3,000 hours because of excess volume of oxygen in working fluid which causes many reactions at the beginning. When the oxygen decreases after 1,000 hours, it causes the reaction to decrease too and get the most concentration of copper particles, i.e. 18.57228 ppm or 0.40859 mg.

Corrosion-dependant maintenance must also be factored into the design. Producing reliable equipment that will become standardized and fixing the time for proper maintenance will require individuals that are knowledgeable about the materials that are going to be used in the design of such equipment. Nowadays, the lack of detailed data of working fluids effect, working temperatures and duration of testing of the CLOHP/CV focuses on determining the actual inner surface corrosion. Therefore, this research aimed to study the parameters affecting corrosion of the CLOHP/CV in a system in clear that will be basic data to be used in future research.