Plasma Nitriding of 90CrMoV8 Tool Steel for the Enhancement of Hardness and Corrosion Resistance

The aim of the study is to apply a plasma nitriding process to the 90CrMoV8 steel commonly employed in wood machining, and to determine its efficiency to improve both mechanical and electrochemical properties of the surface. Treatments were performed at a constant N2:H2 gas mixture and by varying the temperature and process duration. The structural and morphological properties of nitrided layers were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM) coupled with EDS microanalyses. Surface hardening and hardness profiles were evaluated by micro hardness measurements. To simulate the woodmachining conditions, electrochemical tests were carried out with an oak wood electrolyte with the purpose of understanding the effects of the nitriding treatment on the corrosion resistance of the tool in operation. X-ray diffraction analyses revealed the presence of both γ′ (Fe4N) and ε (Fe2–3N) nitrides with a predominance of the ε phase. Moreover, α-Fe (110), γ′ and ε diffraction peaks were shifted to lower angles suggesting the development of compressive stresses in the post nitrided steel. As a result, it was shown that nitriding allowed a significant hardening of steel with hardness values higher than 1200 HV. The diffusion layers were always composed of an outer compound layer and a hardened bulk layer which thickness was half of the total diffusion layer one.No white layer was observed. Similarly, no traces of chromium nitrides were detected. The temperature seemed to be a parameter more influent than the process duration on the morphological properties of the nitrided layer, while it had no real influence on their crystallinity. Finally, the optimal nitriding conditions to obtain a thick and hard diffusion layer are 500 °C for 10 h. On the other hand, to verify the effect of these parameters on the corrosion resistance, potentiodynamic polarization tests were carried out in an original “wood juice” electrolyte. After corrosion, surface was then observed at the SEM scale. Electrochemical study indicated that the untreated steel behaved as a passive material. Although the very noble character of steel was somewhat mitigated and the corrosion propensity increased for nitrided steels, the passive-like nature of themodified surfacewas preserved. For the same optimized parameters as those deduced from the mechanical characterization (500 °C, 10 h), surface presented, in addition to a huge surface hardening, a high corrosion resistance.Regional Council of Burgundy and EGID

Does Internet Banking Affect the Performance of Community Banks?

This study examines the impact of online banking on bank performance. Results show that online banking improves bank earnings as well as helps in improving asset quality.Research and Development/Tech Change/Emerging Technologies,

Bending Of Aelotropic Blocks II

In part I the authors had obtained a solution for bending an aelotropic circular block into an ellipsoidal and obtained the solution for the problem of bending and aelotropic circular block into a spherical shell as a particular case. In this paper, the solution for bending a circular block into a paraboloidal shell has been obtained on the same lines in terms of a completely general energy function for both compressible and incompressible materials

Finite Bending of Blocks

The problem of bending of a circular block with concentric hole into ellipsoidal shell is considered, and the earlier results have been obtained as particular cases

Channa Reddy In Telangana Statehood Movement: Initiation, Intervention And Contribution

The present paper tries to explore some of the repeated accusations and half-truths against the Telangana leader – Dr. Marri Channa Reddy, who led the movement in 1969. It is believed that the leaders started the Telangana Statehood movement as a problem-solving movement against subregionalism. Dr. Reddy was a staunch opponent of Andhra’s internal colonization. This is not only absurd but also a parody of the truth. This is mainly due to the lack of original documents in an organized campaign for the separate state of Telangana. The print and electronic media reports speak of alarming national integration at the request of the state of Telangana. While national integration can no longer be mere integration, biased politicians and media cannot accept the exclusive right to speak on behalf of the common man. Therefore, an ordinary person needs to understand how effectively the public and leader’s participation took place in the country\u27s democratic and political process in articulating their rights and entitlements. And, thus, the initiation, intervention, and contribution of a prominent political leader of Telangana State were discussed in this paper with substantial shreds of evidence

Photoplethysmography

The process of breathing occurs as a physiological cycle in which one nasal cavity is functionally active while the other is resting, i.e., breathing alternates between the nostrils according to a regular pattern referred to as the "nasal cycle" and this cycle has been found to have a profound effect on a number of brain functions. It is suspected that some cross coupling exists between the dominant nostril and the active cerebral hemisphere. It is believed that breathing has a profound effect on man's physical/psychological functioning and is the link between the body and the mind. Pranayama is a well-proven technique for controlled rhythmic breathing with beneficial effects reported both for the body and the mind. In this study the arterial blood volumetric changes from 10 normal breathing subjects and 30 subjects practicing pranayama are monitored non-invasively at the earlobes using optical sensors. This method is known as Photoplethysmography (PPG). Spectral analysis and Heart Rate Variability (HRV) studies are performed on the collected PPG data. The results show fundamental changes in the spectral components of the PPG signal in relation to the breathing brought about by pranayama. In addition, a bi-nasal respiratory airflow monitor is designed and developed for this study utilizing miniature thermistors that can be introduced into the two nostrils of the subject without causing discomfort to the subject. Another study is also reported in which changes in microcirculation in chakra points were studies as a result of concentration on these points. Results indicate the low frequency component around 0.18 Hz changes dramatically during these procedures. Concentration on heart increases the amplitude of the low frequency by about 4.5 times. Concentration on the eyebrow chakra increases the value of this component by about 3 times, but the curve is much broader showing more "power" in that band of frequencies. Since prana or chi is related to amount of blood flow, it is likely the increase in microcirculation is related to increase in prana, as suggested in ancient texts. Further work is contemplated to peruse this line of thinking through standard clinical methods

THE ANTIOXIDANT STUDIES OF TWO MEDICINAL PLANTS, SPHAERANTHUS INDICUS AND PSOPHOCARPUS TETRAGONOLOBUS

Objective: The present study deals with the antioxidant assays of the different leaf extracts of two medicinal plants, Sphaeranthus indicus and Psophocarpus tetragonolobus. Methods: Dried leaves of S. indicus and P. tetragonolobus were packed in separate round bottom flasks for sample extraction using ethanol, methanol, hexane, and distilled water as solvents for 72 h, and the extracts were collected after evaporating the solvents. Antioxidant studies of the various extracts were performed by 1-diphenyl-2-picrylhydrazyl and Ferric Reducing Ability of Plasma assays.Results: Among the two plants studied, S. indicus showed better 2-diphenyl-1-picryl-hydrazyl (DPPH), scavenging activity than P. tetragonolobus with IC50 values of 174.380 and 262.313, respectively, as compared to that of the standard, ascorbic acid, IC50 value of which being 111.16. The FRAP assay results for both the plants indicated that the methanol fractions showed closer results when compared with standards, ascorbic acid and quercetin. The IC50 value of S. indicus, P tetragonolobus, ascorbic acid, and quercetin was 70.065, 151.953, 85.162, and 79.647, respectively. These results clearly indicate that S. indicus methanol fraction had better antioxidant activity when compared to both standards.Conclusion: It is concluded that S. indicus and P. tetragonolobus have excellent antioxidant activities which could be the major contributing factors for their medicinal roles. Further studies in this direction are being carried on

Photoplethysmography

The process of breathing occurs as a physiological cycle in which one nasal cavity is functionally active while the other is resting, i.e., breathing alternates between the nostrils according to a regular pattern referred to as the "nasal cycle" and this cycle has been found to have a profound effect on a number of brain functions. It is suspected that some cross coupling exists between the dominant nostril and the active cerebral hemisphere. It is believed that breathing has a profound effect on man's physical/psychological functioning and is the link between the body and the mind. Pranayama is a well-proven technique for controlled rhythmic breathing with beneficial effects reported both for the body and the mind. In this study the arterial blood volumetric changes from 10 normal breathing subjects and 30 subjects practicing pranayama are monitored non-invasively at the earlobes using optical sensors. This method is known as Photoplethysmography (PPG). Spectral analysis and Heart Rate Variability (HRV) studies are performed on the collected PPG data. The results show fundamental changes in the spectral components of the PPG signal in relation to the breathing brought about by pranayama. In addition, a bi-nasal respiratory airflow monitor is designed and developed for this study utilizing miniature thermistors that can be introduced into the two nostrils of the subject without causing discomfort to the subject. Another study is also reported in which changes in microcirculation in chakra points were studies as a result of concentration on these points. Results indicate the low frequency component around 0.18 Hz changes dramatically during these procedures. Concentration on heart increases the amplitude of the low frequency by about 4.5 times. Concentration on the eyebrow chakra increases the value of this component by about 3 times, but the curve is much broader showing more "power" in that band of frequencies. Since prana or chi is related to amount of blood flow, it is likely the increase in microcirculation is related to increase in prana, as suggested in ancient texts. Further work is contemplated to peruse this line of thinking through standard clinical methods

In-vitro induction of aerial leaves and of precocious flowering in submerged shoots of Limnophila indica by abscisic acid

Nodal explants of submerged shoots of Limnophila indica (L.) Druce were cultured in Nitsch's liquid medium containing abscisic acid (ABA, 10-9-10-6 M). At 10-7 and 10-6 M, ABA induced typical aerial leaves (entire, ovate, opposite-decussately arranged) even under submerged conditions and completely suppressed the development of water leaves (pinnately dissected and whorled). Flowers that invariably arise from aerial shoots were induced precociously by ABA even on submerged nodes