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The present work investigates the effect of rolling (90% thickness reduction) on phase transformation, mechanical properties, and corrosion behaviour of 304L-austenitic stainless steel through cryorolling and room temperature rolling. The processed steel sheets were characterised through X-ray diffraction (XRD), electron backscattered diffraction (EBSD), and vibrating sample magnetometer (VSM). The analysis of XRD patterns, EBSD scan, and vibrating sample magnetometer results confirmed the transformation of the austenitic phase to the martensitic phase during rolling. Cryorolling resulted in improved tensile strength and microhardness of 1808 MPa and 538 VHN, respectively, as compared to 1566 MPa and 504 VHN for room temperature rolling. The enhancement in properties of cryorolled steel is attributed to its higher dislocation density compared to room temperature rolled steel. The corrosion behaviour was assessed via linear polarisation corrosion tests. Corrosion resistance was found to decrease with increasing rolling reduction in both room temperature rolled and cryorolled specimens. [ABSTRACT FROM AUTHOR]

Rapidly solidified Ni54Fe27-2xGa19+2x (x=0, 1, 2, 3, and 4) ferromagnetic shape memory alloys were made by melt-spinning with variation of Fe and Ga contents to report on the martensitic phase transformation, microstructures, and magnetic properties. Rapid solidification produced pure L21 phase by preventing the formation of γ-phase. To study the effect of heat treatment on the phase transitions, microstructures, and the magnetic properties, the melt-spun ribbons were partly heat treated at different temperatures of 800, 900, 1000, 1100, and 1200 K with holding times of 5, 10, and 15 min followed by either water quenching or air cooling. The microstructures of the as-spun ribbons as revealed by electron microscopy studies exhibited a gradual transition from cellular to dendritic structure with increasing Ga concentration and with the presence of some internal martensitic twin bands at higher Ga content. The ribbons exhibited very low coercivity with high saturation magnetization, as high as ∼87 emu/g (decreasing with Ga concentration). The above-ambient Curie temperature (TC) and the subambient martensitic transition temperature (Tm) were observed to be ∼320 and ∼195 K, respectively. At higher heat treatment temperatures formation of ductile γ phases was observed. [ABSTRACT FROM AUTHOR]

Microstructural evolution in Ti - 6.8Al - 3.2Mo - 1.8Zr - 0.3Si alloy during a newly designed thermomechanical schedule has been systematically studied with the aim of obtaining a suitable microstructure for superplastic forming. The schedule involves prior processing in the β phase field and subsequent rolling in the (α + β) phase field. In all experiments the starting material was thermally or thermomechanically treated in the β phase field and subsequently quenched in order to produce a martensitic structure. The morphology of the primary α in material for hot rolling could be substantially altered from that obtained with the conventional (α + β) processing schedule of two phase titanium alloys. Prior β processed microstructure, (α + β) rolling temperature, and deformation were found to influence the α phase morphology in the alloy. The effect of subsequent annealing in the (α + β) phase field on microstructural stability has been examined. The results show that the proposed thermomechanical processing schedule provides a relatively wide temperature - strain 'processing window' in β and (α + β) phase fields over which a fine grain (< 5 μm) equiaxed α structure can be obtained in Ti - 6.8Al - 3.2Mo - 1.8Zr - 0.3Si alloy. [ABSTRACT FROM AUTHOR]

Prevalence of asymptomatic Hepatitis B carrier state varies in different countries. Surgical procedures are an important mode of dissemination of Hepatitis B virus infection. Five hundred patients whose HBsAg status was not known and had undergone a major operative procedure in the Dhaka Medical College Hospital were screened for HBsAg. Of these, 43 (8.6%) were found to be HBsAg positive. Age, sex, and previous history of jaundice didn't show any relationship with the HBsAg status. But the HBsAg positivity was found to be positively related to the past history of blood transfusion, hospitalization and injections.

One hundred consecutive hypertensive patients with stroke admitted to the medicine units of Dhaka Medical College Hospital were studied. The main objective was to study the extent of drug compliance and control of blood pressure in hypertensive patients who had suffered a stroke. Detailed history and clinical examinations were performed in all patients and outcome was recorded. Of the 100 patients studied there were 73(73%) males, 27 (27%) patients had no formal schooling and 53 (53%) had some education. 48 (48%) patients were from middle class and 36 (36%) were poor, 66 (66%) patients were aware that they were hypertensive though only 8 (12.9%) were taking anti-hypertensive drugs regularly. 62% of the patients had suffered from stroke within 5 years of detection of hypertension, and 15 (15%) patients died in the hospital.