Evaluation of Deformation and Densification Behavior in Sintered Fe-0.8%C-1.0%Mo Steel Preforms

Present investigation is aimed to evaluate the densification behaviour of sintered iron-carbon-molybdenum powder metallurgy steel system under the influence of two different heights – to – diameter ratio, namely 0.40 and 0.75 respectively. The sintered preforms are produced by proper selection of aforementioned materials and mixed in a proportion to yield Fe-0.8%C-1.0%Mo, which were blended to achieve a homogenous mix using pot mill. These powder mixes are consolidated on a suitable die set assembly to make a cylindrical shape of preform of two different aspect ratios using 100tons capacity hydraulic press. Further, the green compacts are sintered and are subjected to cold deformation operation. Incremental step of loadings were applied on the preform under dry friction condition. The critical evaluation of compressive deformation, which contributing for the densification of material reveals that induced strain are linearly contributing to enhance densification till the specimen fracture; however overall resistance to deformation of material is exhibiting in three different responses with respect to enhancement in densification. That is at initially, high resistance to deformation followed by high kinetics of deformation and finally exhibiting little resistance against overall deformation. Although, the aforementioned criteria is common for both the aspect ratios, the applied deformation is little homogeneous when aspect ratio is less that directly contributes to enhance the rate of attainment of densification as little faster

Workability behaviour of Fe-C-Mo steel preforms during cold forging

A systematic method to construct the workability diagram for powder metallurgy (P/M) materials has been proposed. Preforms of Fe-0.8%C, Fe-0.8%C-1%Mo and Fe-0.8%C-2%Mo were prepared to the relative density of 0.86 with two different geometries through primary operations of P/M processes. Each sintered preform was cold upset forged with incremental compressive loading of 0.04MN under three different lubricant conditions till a visible crack appeared at the free surface. Oyane's fracture criterion was used to develop a theory to study P/M products. The least square method was used to determine the constants in fracture criteria and these equations were eventually used to construct workability diagram. It is found that the proposed method was well in agreement with the experimental results

Towards the Formal Reliability Analysis of Oil and Gas Pipelines

It is customary to assess the reliability of underground oil and gas pipelines in the presence of excessive loading and corrosion effects to ensure a leak-free transport of hazardous materials. The main idea behind this reliability analysis is to model the given pipeline system as a Reliability Block Diagram (RBD) of segments such that the reliability of an individual pipeline segment can be represented by a random variable. Traditionally, computer simulation is used to perform this reliability analysis but it provides approximate results and requires an enormous amount of CPU time for attaining reasonable estimates. Due to its approximate nature, simulation is not very suitable for analyzing safety-critical systems like oil and gas pipelines, where even minor analysis flaws may result in catastrophic consequences. As an accurate alternative, we propose to use a higher-order-logic theorem prover (HOL) for the reliability analysis of pipelines. As a first step towards this idea, this paper provides a higher-order-logic formalization of reliability and the series RBD using the HOL theorem prover. For illustration, we present the formal analysis of a simple pipeline that can be modeled as a series RBD of segments with exponentially distributed failure times.Comment: 15 page

Epidemiology and Clinicopathological Profile of Renal Cell Carcinoma: A Review from Tertiary Care Referral Centre

Renal cell carcinoma (RCC) accounts for 3% of all adult cancers and 85% of all kidney tumours. Incidence of RCC is lower in Asian region, particularly in India, probably due to lack of reporting. Most of the data about RCC are from Western countries; and data from India are scarce, especially regarding para-neoplastic syndromes. We sought to determine the epidemiology, clinicopathological profile and management of RCCin a tertiary care centre in Western India. This was a retrospective study that involved data analysis of records of RCC patients who presented to our institution from April 2016 to February 2020. Laboratory investigations, including tests for paraneoplastic syndrome (PNS), and relevant radiologic investigations were performed and treatment was offered according to the stage, patient factors and available modalities. A total 142 RCC patients were included in the study. The median age of presentation was 58 years. Most of the patients (67%) were symptomatic, and 33% of the patients were asymptomatic, and the RCC was diagnosed incidentally. A large number of patients (56.3%) had PNS. The most common histopathologic type of RCC was clear cell carcinoma (68.8%), followed by papillary (20%) and chromophobe (8%) carcinoma. 40% of carcinomas with sarcomatoid differentiation were seen in patients under 50 years of age. Two cases of multicystic RCC were both seen in patients less than 50 years of age. 65.5% of the patients presented at Stage 1 and 2. Most surgeries (71.2%) were done in a minimally invasive manner. A significant number of patients were asymptomatic, in which RCC was detected incidentally. The age of presentation was earlier, yet the patients had a higher tumour stage. More than half of the patients had PNSs. Despite growing trend towards Western data, the significantly higher number of patients with PNSs and early age of presentation suggest inherent differences in tumour biology, possibly related to differences in genetic and environmental factors

Plane-symmetric inhomogeneous magnetized viscous fluid universe with a variable Λ\Lambda

The behavior of magnetic field in plane symmetric inhomogeneous cosmological models for bulk viscous distribution is investigated. The coefficient of bulk viscosity is assumed to be a power function of mass density $(\xi =\xi_{0}\rho^{n})$. The values of cosmological constant for these models are found to be small and positive which are supported by the results from recent supernovae Ia observations. Some physical and geometric aspects of the models are also discussed.Comment: 18 pages, LaTex, no figur

Measurement of the Bottom-Strange Meson Mixing Phase in the Full CDF Data Set

We report a measurement of the bottom-strange meson mixing phase \beta_s using the time evolution of B0_s -> J/\psi (->\mu+\mu-) \phi (-> K+ K-) decays in which the quark-flavor content of the bottom-strange meson is identified at production. This measurement uses the full data set of proton-antiproton collisions at sqrt(s)= 1.96 TeV collected by the Collider Detector experiment at the Fermilab Tevatron, corresponding to 9.6 fb-1 of integrated luminosity. We report confidence regions in the two-dimensional space of \beta_s and the B0_s decay-width difference \Delta\Gamma_s, and measure \beta_s in [-\pi/2, -1.51] U [-0.06, 0.30] U [1.26, \pi/2] at the 68% confidence level, in agreement with the standard model expectation. Assuming the standard model value of \beta_s, we also determine \Delta\Gamma_s = 0.068 +- 0.026 (stat) +- 0.009 (syst) ps-1 and the mean B0_s lifetime, \tau_s = 1.528 +- 0.019 (stat) +- 0.009 (syst) ps, which are consistent and competitive with determinations by other experiments.Comment: 8 pages, 2 figures, Phys. Rev. Lett 109, 171802 (2012

Phytochemical-loaded mesoporous silica nanoparticles for nose-to-brain olfactory drug delivery

Central nervous system (CNS) drug delivery is often hampered due to the insidious nature of the blood-brain barrier (BBB). Nose-to-brain delivery via olfactory pathways have become a target of attention for drug delivery due to bypassing of the BBB. The antioxidant properties of phytochemicals make them promising as CNS active agents but possess poor water solubility and limited BBB penetration. The primary aim of this study was the development of mesoporous silica nanoparticles (MSNs) loaded with the poorly water-soluble phytochemicals curcumin and chrysin which could be utilised for nose-to-brain delivery. We formulated spherical MSNP using a templating approach resulting in ∼220nm particles with a high surface porosity. Curcumin and chrysin were successfully loaded into MSNP and confirmed through Fourier transformation infrared spectroscopy (FT-IR), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA) and HPLC approaches with a loading of 11-14% for curcumin and chrysin. Release was pH dependant with curcumin demonstrating increased chemical stability at a lower pH (5.5) with a release of 53.2%±2.2% over 24h and 9.4±0.6% for chrysin. MSNP were demonstrated to be non-toxic to olfactory neuroblastoma cells OBGF400, with chrysin (100μM) demonstrating a decrease in cell viability to 58.2±8.5% and curcumin an IC50 of 33±0.18μM. Furthermore confocal microscopy demonstrated nanoparticles of <500nm were able to accumulate within cells with FITC-loaded MSNP showing membrane localised and cytoplasmic accumulation following a 2h incubation. MSNP are useful carriers for poorly soluble phytochemicals and provide a novel vehicle to target and deliver drugs into the CNS and bypass the BBB through olfactory drug delivery

Quantitative analyses and modelling to support achievement of the 2020 goals for nine neglected tropical diseases

Quantitative analysis and mathematical models are useful tools in informing strategies to control or eliminate disease. Currently, there is an urgent need to develop these tools to inform policy to achieve the 2020 goals for neglected tropical diseases (NTDs). In this paper we give an overview of a collection of novel model-based analyses which aim to address key questions on the dynamics of transmission and control of nine NTDs: Chagas disease, visceral leishmaniasis, human African trypanosomiasis, leprosy, soil-transmitted helminths, schistosomiasis, lymphatic filariasis, onchocerciasis and trachoma. Several common themes resonate throughout these analyses, including: the importance of epidemiological setting on the success of interventions; targeting groups who are at highest risk of infection or re-infection; and reaching populations who are not accessing interventions and may act as a reservoir for infection,. The results also highlight the challenge of maintaining elimination 'as a public health problem' when true elimination is not reached. The models elucidate the factors that may be contributing most to persistence of disease and discuss the requirements for eventually achieving true elimination, if that is possible. Overall this collection presents new analyses to inform current control initiatives. These papers form a base from which further development of the models and more rigorous validation against a variety of datasets can help to give more detailed advice. At the moment, the models' predictions are being considered as the world prepares for a final push towards control or elimination of neglected tropical diseases by 2020

Search for black holes and other new phenomena in high-multiplicity final states in proton-proton collisions at root s=13 TeV

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