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991.
R Radhakrishnan R Srinivasan K Krishnamoorthy S Sabesan SP Pani 《Canadian Metallurgical Quarterly》1994,7(3):117-118
In patients with filarial lymphoedema of the limbs, infestation by maggots is extremely rare. We saw three patients with lymphoedema who harboured Chrysomyia bezziana in leg ulcers and in one of them 128 maggots were recovered. A course of local dressing, antibiotics and anti-inflammatory drugs resulted in healing of the wounds. Ulcers in patients with lymphoedema should be carefully tended with cleaning and dressing otherwise myiasis may supervene. 相似文献
992.
Group technology tries to exploit the similarity between parts and machines and forms machine groups and part families. Just-in-time production tries to manufacture the parts whenever required there by reducing the inventory and eliminating waste.
In order to apply JIT in a GT cell, the cell is divided into modules and parts move from one module to another in small transfer batches. This paper addresses the problem of operator allocation for the modules and sequencing the variety of parts with the objective of minimizing the makespan.
Six different methodologies have been presented and the results compared in terms of makespan and computational time. 相似文献
993.
J Srinivasan DW Newell M Sturzenegger MR Mayberg HR Winn 《Canadian Metallurgical Quarterly》1996,27(7):1226-1230
BACKGROUND AND PURPOSE: A subject with dissection of the internal carotid artery (ICA) may present with a variety of symptoms, from headache to stroke. Thus far, it has not been possible to identify the subset of patients at risk for cerebral ischemia. Because the majority of these ischemic events are secondary to embolic phenomena, we used transcranial Doppler (TCD) evaluation with emboli monitoring to study 17 consecutive patients with ICA dissection treated at Harborview Medical Center, Seattle, Wash, during a 2-year period from 1992 until 1994. METHODS: Ten patients with ICA dissection secondary to trauma and seven with spontaneous ICA dissection were diagnosed by carotid angiography and studied by TCD from the time of diagnosis through initiation of therapy. Emboli monitoring was performed in the middle cerebral artery (MCA) ipsilateral to the dissection at the initial evaluation and intermittently thereafter to ensure that the emboli stopped with treatment. RESULTS: Emboli were detected in the MCA distal to the dissection in 10 of 17 patients (59%). Patients with microemboli detected by TCD presented with a stroke (70%) much more frequently than those without emboli (14%) (P=.0498). The presence of a pseudoaneurysm did not increase the risk of either microemboli or stroke. CONCLUSIONS: We have demonstrated a high incidence of intracranial microemboli in the MCA distal to carotid dissections and a significant correlation between the presence of emboli and stroke. TCD can therefore be used as an adjunctive tool to manage patients with suspected carotid dissection and may prove useful in evaluating the efficacy of treatment in reducing microemboli and subsequent stroke. 相似文献
994.
155 W continuous-wave output power from a 1 cm wide monolithic AlGaAs/InGaAs laser diode array with an emitting aperture of 4800 μm has been demonstrated at a cooling water temperature of 3°C. A continuous-wave output power of 72 W was achieved at room temperature with an emitting aperture of 1600 μm. High T0 was observed for the laser structures 相似文献
995.
The band structures, absorption coefficients, and Auger recombination rates in narrow-gap alloys HgCdTe, InTIP, InTlAs, and
InTlSb in the zinc blende structure, along with those of GaAs, are calculated using a hybrid pseudopotential and tight-binding
method. The composition-dependent band gaps of the thallium-based alloys are reported along with those of several other semiconductor
alloys. Within 50 meV from the absorption edge, the absorption coefficient of InxTl1−xP is found to have about the same magnitude as that of HgxCd1−xTe and GaAs, while that of InxTl1−xAs and InxTl1−xSb is much smaller. In agreement with previous theories, the calculated Auger lifetimes in Hg0.78Cd0.22Te with unit or k • p overlap agree very well with experiments. Among the thallium alloys studied, the Auger lifetimes are
longest in In0.33Tl0.67P, but still shorter than those in Hg0.78Cd0.22Te by an order of magnitude. In addition, realistic overlaps produce lifetimes one to two orders of magnitude larger than
those observed. 相似文献
996.
An analysis of temperature dependence of saturated liquid density along the liquid vapour coexistence curve shows that a plot of reduced properties Tr(=T/Tc) against Tr?r (=T?/Tc?c), goes through a maximum at a particular Tr for all the following liquids: Ne, Ar, Kr, Xe, N2, O2, CH4, C2H6, C2H4, CO2, R11, 12, 12B1, 13, 13B1, 14, 21, 22, 23, 32, 40, 113, 114, 115, H2O and NH3. For all these liquids, except NH3, Tr is ≈ 0.82, whether they are polar, non-polar, monoatomic or polyatomic. This characteristic temperature, , has been used to evaluate the energy parameter and the corresponding molar volume has been used to evaluate the length parameters for calculation of reduced critical properties. is also found to be a point of inflexion on the saturated liquid viscosity versus temperature plot. 相似文献
997.
This article describes a hybrid air-conditioning system consisting of a conventional R-22 vapor compression refrigeration system cascaded with a solar-operated, ammonia-water, vapour absorption system. The condenser of the R-22 system is cooled by the evaporator of the the ammonia system. This facilitates operation of the R-22 system at a low condensing temperature and pressure. This is found to yield considerable savings in electrical energy consumption by the compression system. 相似文献
998.
P. Selvam B. Viswanathan V. Srinivasan 《International Journal of Hydrogen Energy》1989,14(12):899-902
XPS and XAES studies of air-exposed Mg2Cu and Mg2Ni alloys showed surface decomposition and preferential segregation of Mg by the influence of oxygen and moisture. The segregated magnesium is mostly present as oxide and hydroxide on the surface. The second metallic component namely Ni or Cu is also present in the oxidized state. The passivation of these alloys arises by the oxidation of the transition metal component. We suggest that the activation of these alloys involves reduction of the oxidized 3d elements and the formation of metallic clusters. 相似文献
999.
This paper presents results of experimental investigations on a field of 8 photovoltaic panels assembled 2 in series and 4 such parallel combinations. The diurnal and environmental effects have been characterized systematically. The usage conditions are clean and dusty states of panels, the centers of each series combinations shorted and unshorted. It is observed that the curvature at the maximum power point of the I–V curve could be an indicator of the panel characteristics. The temperature effects on the voltage at the maximum power point are also discussed. It is brought out that field evaluation is essential and often maximum power point tracking can be dispensed if a known load exists and a judicious choice of battery bank capacity is made. 相似文献
1000.
Dense and uniform arrays of InP-based nanopillars were fabricated by dry etching using self-assembly of colloidal silica particles for masking. The pillars, both single and arrays, fabricated from epitaxially grown InP and InP/GaInAsP/InP quantum well structures show excellent photoluminescence (PL) even at room temperature. The measured PL line widths are comparable to the as-grown wafer indicating high quality fabricated pillars. A stamping technique enables transfer with arbitrary densities of the nanopillars freed from the substrate by selectively etching a sacrificial InGaAs layer. 相似文献