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81.
Ki-1 large cell anaplastic lymphoma is a recently described variant of malignant lymphoma. A retrospective study of 10 cases of Ki-1 lymphoma was carried out at the Armed Forces Institute of Pathology (AFIP) Rawalpindi to document its clinical and morphological features. The morphological features were evaluated by a study of paraffin embedded sections stained with haematoxylin and eosin stains. Immunohistochemical stains for BER-H2 and leucocyte common antigen (LCA) were performed in all cases. The age of the patients ranged from 2 to 60 years and male to female ratio was 2.3:1. Cervical lymphadenopathy was the most common presentation. Histologically, there was a complete effacement of the lymph node architecture in 8 cases. The Reed-Sternberg like cells were seen in 2 and histiocyte like cells in 7 cases. Immunohistochemically all cases were positive for BER-H2. It is suggested that the possibility of Ki-1 lymphoma should be considered in all cases of lymphoma with pleomorphic morphology.  相似文献   
82.
83.
Jamal Khan   《Thin solid films》1992,220(1-2):222-226
A lapping process for achieving high quality alumina (Al2O3) surfaces was investigated. Alumina films were sputter deposited on thick TiC---Al2O3 ceramic wafers. Polishing of these films was carried out on pitch plates (organic resin melted and set on the circular disk of a lapping machine). Abrasives with different grit sizes, 0.05–1.0 μm, were tried together with different lapping process parameters. Qualitu of the lapped surface was studied in terms of roughness and flatness. Stock removal rates were also measured. Correlation of surface quality with lapping parameters was established to achieve process optimization.

Scratch-free polished alumina surfaces were obtained by using this technique. Specific applications of the process in the fabrication of magnetic recording devices are indicated.  相似文献   

84.
85.
This paper presents the development of a multipurpose simulator with the general model describing a four-component, three-phase (oil, aqua, gas), multi-dimensional, finite-difference polymer injection simulator. The model uses a block-centered grid and a seven-point finite-difference scheme. Fluid saturations and pressure distributions are obtained from a fully implicit formulation using Newton's method, whereas polymer concentration is obtained, in a subsequent step, explicitly using the method of cascade. Practical features of the present simulator include: (1) a truly multipurpose simulation; and (2) ease of preparing a batch data file required for the simulator. A novel and simple procedure is implemented to reduce the general model of the polymer injection simulator (polymer, oil, aqua, and gas) to: (1) three-phase black-oil simulator (oil, water, and gas); (2) two-phase black-oil simulators (oil and water, oil and gas, or water and gas); (3) two-phase polymer injection simulator (polymer, oil, and aqua); and (4) one-phase simulators (oil, water, or gas) with only the relevant equations being solved at the matrix level for each simulator. Guidelines for other practical features are also presented.The simulator was tested and verified using a polymer injection test problem and a gas injection bench mark test problem both reported in the literature. The simulator was also used to model a field case and some results are highlighted.  相似文献   
86.
Thegem-dibromocyclopropanation of naturally occurring unsaturated hydroxy fatty esters, methyl ricinoleate (I) and methyl isoricinoleate (II), has been undertaken to provide compounds which might have potential utility. Phenyl(tribromomethyl)mercury reacts only with the carbon-carbon double bond of each substrate, leaving the OH group intact. The product, methyl 9,10-dibromomethylene-12-hydroxyoctadecanoate (III) and methyl 12,13-dibromomethylene-9-hydroxyoctadecanoate (IV), obtained from I and II, respectively, were characterized by elemental, infrared (IR) and nuclear magnetic resonance (NMR) analyses.  相似文献   
87.
Statistics show that fatigue crack development comes first and foremost as a damage source in aerospace metallic structures. Currently, widespread methods are available to inspect these structures, but they are quite time-consuming, costly and require the structural system to be idle. Next, attempts to develop damage detection integrated systems are paramount for the safety and cost of such structures. This paper describes an investigation into the feasibility of using an integrated system based on Lamb waves in order to assess the integrity of riveted aluminium joints during cyclical loading. In this experimental analysis, Lamb waves are excited and received outside the joint area using piezoelectric transducers coupled onto the plates. The detected damage is cracks in joint resulting from fatigue loading. The collected signals on the piezoelectric transducers are analysed using Hilbert transform and time–frequency analysis. It is shown that the final interpretation of Lamb wave analysis may provide a means of sizing the defects and following the crack development. In addition to that, an acoustic emission system is used jointly with the Lamb wave analysis in order to discuss results and damage development. Finally, it is demonstrated that both methods can work together and the results obtained are in good agreement.  相似文献   
88.
Food Science and Biotechnology - Recently, considerable attention has been paid to drug exploration from natural sources for treating memory loss, a major manifestation of various neurodegenerative...  相似文献   
89.
A food safety management system (FSMS)‐diagnostic instrument was applied in 22 dairy processing companies to analyse the set‐up and operation of core control and assurance activities in view of the risk characteristics of the systems' context. Three clusters of companies were identified differing in levels of set‐up and operation of this FSMS and system outputs, but all operated in a similar moderate‐risk context. Microbiological assessment of products, environmental and hand samples indicated a poor to moderate food safety level. A two stage intervention approach has been proposed to enable commitment and sustainable improvement for the longer term.  相似文献   
90.
Opopanax gum/gelatin nanofibre was produced by the electrospinning method, and the efficiency of this new technique for encapsulation of garlic essential oil was investigated. Fourier-transform infrared spectroscopy results showed the physical and weak interactions between opopanax gum and gelatin, as well as the improvement of their thermal stability in the nanofibres structure. Incorporating 10% garlic essential oil based on biopolymer weight in nanofibres was considered the best percentage. The results confirmed the presence of garlic essential oil in the nanofibres and the improvement of its thermal stability by entrapment to the nanofibre structure. The data of analysis of the stability of garlic essential oil in the forms of free and encapsulated conditions showed that its stability increased at 25 °C from 20 days to more than 60 days. It indicated the efficiency of opopanax gum/gelatin nanofibres as an applicable coating material for stability enhancement of essential oils.  相似文献   
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