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71.
Recursive least squares (RLS) adaptive noise cancellation (ANC) and wavelet transform (WT) ANC have been applied and compared for heart sound (HS) reduction from lung sounds (LS) recordings. Novel processes for quantitative and qualitative evaluation of any method for HS reduction from LS have also been proposed.  相似文献   
72.
We have demonstrated the electroluminescent (EL) properties of 2-mercaptobenzothiazolate complexes of rare earth metals [Ln(mbt)3, Ln = Y, Sm, Eu, Gd, Tb, Dy, Tm] using simple non-doped two-layer organic light emitting diode with the configuration of indium tin oxide/N,N′-bis(3-methylphenyl)-N,N′-diphenylbenzidine/Ln(mbt)3/Yb. It was found that 2-mercaptobenzothiazolate complexes have highly efficient intra-energy transfer from the singlet to the triplet state of the ligand, and then to the excited state of the central lanthanide ions. Thus Y(mbt)3 and Gd(mbt)3 exhibit the broad ligand-centered emission with maximum near 600 nm and Dy(mbt)3, Tb(mbt)3 and Tm(mbt)3 complexes exhibit pure sharp emission bands from the intra f–f transitions of lanthanide ions Tb3+: 5D4  7F6 (492 nm), 5D4  7F5 (547 nm), 5D4  7F4 (589 nm), 5D4  7F3 (624 nm); Dy3+: 4F9/2  6H13/2 (575 nm) and Tm3+: 3H43H6 (795 нм).  相似文献   
73.
Bose and Lin introduced a class of systematic codes for detection of binary asymmetric errors. In this note, we describe a generalization to q-ary asymmetric error detecting codes. For these codes, the possible undetectable errors are characterized and the undetectable errors of minimum weight are determined  相似文献   
74.
The current industrial production of aluminum from alumina is based on the electrochemical Hall-Héroult process, which has the drawbacks of high-greenhouse gas emissions, reaching up to 0.70 kg CO2-equiv/kg Al, and large energy consumption, about 0.055 GJ/kg Al. An alternative process is the carbothermic reduction of alumina. Thermodynamic equilibrium calculations and experiments by induction furnace heating indicated that this reaction could be achieved under atmospheric pressure only above 2200°C. Lower required reaction temperatures can be achieved by alumina reduction under vacuum. This was experimentally demonstrated under simulated concentrated solar illumination and by induction furnace heating. By decreasing the CO partial pressure from 3.5 mbar to 0.2 mbar, the temperature required for almost complete reactant consumption could be decreased from 1800°C to 1550°C. Deposits condensed on the relatively cold reactor walls contained up to 71 wt% of Al. Almost pure aluminum was observed as Al drops, while a gray powder contained 60–80% Al and a yellow-orange powder contained only Al4C3, Al-oxycarbides and Al2O3.  相似文献   
75.
The demand for equality of recognition or respect is the dominant passion of modernity. The 20th century experienced a giant leap in technological inventiveness and ruthless use of technological power. In the 21st century, human welfare and environmental wellbeing demand fundamental political appraisal. We have the means, if we choose, to eradicate poverty and to responsibly protect the global environment. However, economic, political and cultural systems act to differentially allocate the benefits and risks for growth between socioeconomic groups. For example, it is a matter of pride that the neonatal mortality rate in affluent societies has dropped substantially since the late 1970s. However, the level of infant mortality (three times the national average) and low birthweight (13%) among the Indigenous Australian population is the highest in the country. With hindsight we now know that is the inevitable legacy of Australia's colonial history. Chronic physical and psychological stress is recognized as an important etiological factor in many lifestyle diseases of the cardiovascular, immune and reproductive systems. Diseases of adaptation are further advanced by non-adaptive lifestyle choices, depression, alcoholism and other drug dependencies. This review describes the principles of bioscience ethics and targets equity issues as they affect human reproduction across generations with particular reference to the Indigenous population of Australia. The review also considers ways we may advance global and cultural maturity from the Indigenous Australian perspective and proposes an ecologically based model of preventative care. If we are to embrace fundamental social change and protect future children without threatening parents' basic freedoms, then new beliefs and priorities--based on a compassionate understanding of biological systems--must evolve from the general public. Belief in human rights arising from a sense of human dignity is a collective outcome originating from individual commitment. The golden rule; that is, Nature's principle of reciprocity, is fundamental in bridging the gap between knowledge and effective action.  相似文献   
76.
General regularity of preparation of fibrous textured protein from field bean globulin fraction by wet non-spinneret spinning and the water absorption capacity of the textured protein were investigated. The optimal conditions for this process for minimum protein loss in the coagulation bath were determined. Use of a highly concentrated neutral protein solution (>500 g litre?1) as a dope avoids the need for neutralisation and washing of the textured product. The textured protein obtained had a microfibrous structure.  相似文献   
77.
This study investigates the influence of different types of reinforcing fillers on the mechanical properties and wettability of wood–plastic composite material. Micro-sized glass fibers (GF) and carbon fibers (CF) and nano-sized montmorillonite (MMT) were used to reinforce a polypropylene/wood flour composite. Clear improvement of the tensile strength and modulus, up to 20 and 29 %, respectively, was observed when GF was loaded; the impact strength was reduced by 7 %; the hardness of the composite was improved by up to 7 %. No significant change in the tensile strength was observed after the CF loading; the tensile modulus was improved by 18 %; the impact strength of the composite was reduced and hardness was improved by 19 and 7 %, respectively. The MMT enhanced the tensile modulus by 34 %; the other studied mechanical properties, tensile and impact strengths, as well as the hardness of the composite decreased by 12, 32 and 15 %, respectively. The water absorption level decreased with all three filler type loadings. The morphology of the composites was examined using a scanning electron microscope (SEM).  相似文献   
78.
With the use of the iteration method and bilinear functional based on two-dimensional volume integral equation, LM modes existing in a plane-layered dielectric waveguide and quasi-LM modes existing in a multilayered rectangular dielectric waveguide are studied. The semiconductor layers are described as a homogeneous single-component dissipative plasma that can exhibit negative conductivity owing to external electric field. The results obtained for a homogeneous single-layer rectangular waveguide are compared to the results obtained with a model of a planar single-layer waveguide. Structures with passive and active semiconductor-plasma layers are investigated. It is shown that amplification is possible at frequencies above the cutoff frequency and that the dispersion laws below the cutoff are complicated.  相似文献   
79.
Thermodynamics of the Na1−xLi x NbO3 system is investigated by high-temperature drop-solution calorimetry in molten 3Na2O–4MoO3 solvent at 973 K. Standard molar enthalpies of formation are derived. The estimated heats of transition between hypothetical and stable structures, lithium niobate and perovskite for NaNbO3 and vice versa for LiNbO3 are −6 kJ/mol and −10 kJ/mol, respectively. X-ray diffraction studies at room temperature showed for 0 ≤ x ≤ 0.14 there are three phases based on different ordering of the perovskite type lattice: orthorhombic with a quadrupled reduced perovskite cell at 0 ≤ x ≤ 0.02, orthorhombic with a doubled reduced perovskite cell at 0.015 ≤ x ≤ 0.14, and rhombohedral at 0.08 ≤ x ≤ 0.13. There are two two-phase (morphotropic) regions with coexistence of the two orthorhombic phases at 0.015 ≤ x ≤ 0.02 and with the second orthorhombic phase coexisting with the rhombohedral phase at 0.08 ≤ x ≤ 0.13. A reproducible anomaly in specific heat at ∼600 K, not reported previously, has been observed in pure NaNbO3. Heat-capacity measurements confirm a phase transition at 553 K for 0.07 ≤ x ≤ 0.09. With increasing lithium concentration, a gradual disappearance of high-temperature phase transitions associated with tilting of oxygen octahedra has been observed.  相似文献   
80.
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