991 resultados para Part songs, Italian.
Resumo:
The methoxycyclophosphazenes [NP(OMe),], (n = 3-6) rearrange on heating to give oxocyclophosphazanes, [N(Me)PO(OMe)],. Isomeric products are formed when n = 4-6. The lH, ,lP, and 13C n.m.r. data for the starting materials and the products are presented. The ethoxy- and n-propoxy-derivatives N,P,( OR)* do not undergo the above rearrangement. The geminal derivatives N,P,R,(OMe), (R = Ph or NHBut) on heating yield both fully and partially rearranged products, namely dioxophosphaz-1 -enes and oxophosphazadienes, as shown by 270- MHz lH n.m.r. spectroscopy. The non-geminal derivative N,P,( NMe,),(OMe), gives only the fully rearranged product N,Me,P,(NMe,),O,(OMe), whose structure has been established from its lH and 31P n.m.r. spectra.
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Several channels provided by many-body couplings — both fermion-fermion and fermion-boson — for the evolution of the chemisorption system are discussed. This provides an opportunity of a systematic study of the effects of correlations reflected through the intricate pole structure of the absorbate Green functions. The results of Newns, Anda and others in the context of chemisorption are generalized.
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Several boson subsystems may be involved in electrosorption phenomena. To accommodate this possibility, the one-boson formalism described in Parts I–III is extended to this case. The hierarchy in the superoperator scheme, the evaluation of operator averages for closure and several special cases are indicated. As an illustration, some calculations are presented to indicate the trends of many-body corrections in chemisorption.
Resumo:
With many innovations in process technology, forging is establishing itself as a precision manufacturing process: as forging is used to produce complex shapes in difficult materials, it requires dies of complex configuration of high strength and of wear-resistant materials. Extensive research and development work is being undertaken, internationally, to analyse the stresses in forging dies and the flow of material in forged components. Identification of the location, size and shape of dead-metal zones is required for component design. Further, knowledge of the strain distribution in the flowing metal indicates the degree to which the component is being work hardened. Such information is helpful in the selection of process parameters such as dimensional allowances and interface lubrication, as well as in the determination of post-forging operations such as heat treatment and machining. In the presently reported work the effect of aperture width and initial specimen height on the strain distribution in the plane-strain extrusion forging of machined lead billets is observed: the distortion of grids inscribed on the face of the specimen gives the strain distribution. The stress-equilibrium approach is used to optimise a model of flow in extrusion forging, which model is found to be effective in estimating the size of the dead-metal zone. The work carried out so far indicates that the methodology of using the stress-equilibrium approach to develop models of flow in closed-die forging can be a useful tool in component, process and die design.
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In an effort to develop a fully computerized approach for structural synthesis of kinematic chains the steps involved in the method of structural synthesis based on transformation of binary chains [38] have been recast in a format suitable for implementation on a digital computer. The methodology thus evolved has been combined with the algebraic procedures for structural analysis [44] to develop a unified computer program for structural synthesis and analysis of simple jointed kinematic chains with a degree of freedom 0. Applications of this program are presented in the succeeding parts of the paper.
Resumo:
The reliability of the computer program for structural synthesis and analysis of simple-jointed kinematic chains developed in Part 1 has been established by applying it to several cases for whuch solutions are either fully or partially available in the literature, such as 7-link, zero-freedom chains; 8- and 10-link, single-freedom chains; 12-link, single-freedom binary chains; and 9-link, two-freedom chains. In the process some discrepancies in the results reported in previous literature have been brought to light.
Resumo:
The unified computer program for structural synthesis and analysis developed in Part 1 has been employed to derive the new and complete collection of 97 10-link, three-freedom simple-jointed kinematic chains. The program shows that of these chains, 3 have total freedom, 70 have partial freedom and the remaining 24 have fractionated freedom and that the 97 chains yield a total of 676 distinct mechanisms.
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A unified approach to the problem of electrochemical fluctuations is presented. On the basis of the Langevin procedure, primary noise sources are introduced in the basic phenomenological equations and a discussion of the secondary noise sources arising in the expressions for the power spectra of currents is given.
Resumo:
A discussion of the modelling of the primary and secondary noise sources introduced in the formalism of fluctuation phenomena in a previous report is presented. It is illustrated that the generalisation of the modelling of noise sources in mass transport as given by Tyagai is limited in its applicability. A general procedure for the same is discussed in detail.
Resumo:
This dissertation consists of four articles and an introduction. The five parts address the same topic, nonverbal predication in Erzya, from different perspectives. The work is at the same time linguistic typology and Uralic studies. The findings based on a large corpus of empirical Erzya data, which was collected using several different methods and included recordings of the spoken language, made it possible for the present study to apply, then test and finally discuss the previous theories based on cross-linguistic data. Erzya makes use of multiple predication patterns which vary from totally analytic to the morphologically very complex. Nonverbal predicate clause types are classified on the basis of propositional acts in clauses denoting class-membership, identity, property and location. The predicates of these clauses are nouns, adjectives and locational expressions, respectively. The following three predication strategies in Erzya nonverbal predication can be identified: i. the zero-copula construction, ii. the predicative suffix construction and iii. the copula construction. It has been suggested that verbs and nouns cannot be clearly distinguished on morphological grounds when functioning as predicates in Erzya. This study shows that even though predicativity must not be considered a sufficient tool for defining parts of speech in any language, the Erzya lexical classes of adjective, noun and verb can be distinguished from each other also in predicate position. The relative frequency and degree of obligation for using the predicative suffix construction decreases when moving left to right on the scale verb adjective/locative noun ( identificational statement). The predicative suffix is the main pattern in the present tense over the whole domain of nonverbal predication in Standard Erzya, but if it is replaced it is most likely to be with a zero-copula construction in a nominal predication. This study exploits the theory of (a)symmetry for the first time in order to describe verbal vs. nonverbal predication. It is shown that the asymmetry of paradigms and constructions differentiates the lexical classes. Asymmetrical structures are motivated by functional level asymmetry. Variation in predication as such adds to the complexity of the grammar. When symmetric structures are employed, the functional complexity of grammar decreases, even though morphological complexity increases. The genre affects the employment of predication strategies in Erzya. There are differences in the relative frequency of the patterns, and some patterns are totally lacking from some of the data. The clearest difference is that the past tense predicative suffix construction occurs relatively frequently in Standard Erzya, while it occurs infrequently in the other data. Also, the predicative suffixes of the present tense are used more regularly in written Standard Erzya than in any other genre. The genre also affects the incidence of the translative in uľ(ń)ems copula constructions. In translations from Russian to Erzya the translative case is employed relatively frequently in comparison to other data. This study reveals differences between the two Mordvinic languages Erzya and Moksha. The predicative suffixes (bound person markers) of the present tense are used more regularly in Moksha in all kinds of nonverbal predicate clauses compared to Erzya. It should further be observed that identificational statements are encoded with a predicative suffix in Moksha, but seldom in Erzya. Erzya clauses are more frequently encoded using zero-constructions, displaying agreement in number only.
Resumo:
Non-linear planar response of a string to planar narrow band random excitation is investigated in this paper. A response equation for the mean square deflection σ2 is obtained under a single mode approximation by using the equivalent linearization technique. It is shown that the response is triple valued, as in the case of harmonic excitation, if the centre frequency of excitation Ω lies in a certain specified range. The triple valued response occurs only if the excitation bandwidth β is smaller than a critical value βcrit which is a monotonically increasing function of the intensity of excitation. An approximate method of investigating the almost sure asymptotic stability of the solution is presented and regions of instability in the Ω-σ2 plane have been charted. It is shown that planar response can become unstable either due to an unbounded growth of the in-plane component of motion or due to a spontaneous appearance of an out-of-plane component.
Resumo:
The tautomeric behaviour of monohydroxycyclotriphosphazatrienes has been investigated by 31P n.m.r. spectroscopy. These derivatives exist as oxocyclotriphosphazadiene tautomers in which the hydrogen atom is attached to a ring nitrogen atom to the phosphoryl group. Three types of prototropic behaviour are observed : (a) no exchange is detected and only one tautomer is present [e.g. N3HP3(NHBut)2R3O (R = OMe or OEt)]; (b) exchange takes place between two equivalent sites and only one tautomer is observed [e.g. N3HP3R5O (R = OMe or OPh); N3HP3Ph4RO (R = OMe or OEt)]; and (c) exchange occurs between two non-equivalent sites and two tautomers are present [e.g. N3HP3Ph2R3O (R = OMe, OEt, or OPrn)]. It is shown that basicity calculations using substituent constants have predictive value since they are in good agreement with the spectroscopic observations.
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Fibre diameter can vary dramatically along a wool staple, especially in the Mediterranean environment of southern Australia with its dry summers and abundance of green feed in spring. Other research results have shown a very low phenotypic correlation between fibre diameter grown between seasons. Many breeders use short staples to measure fibre diameter for breeding purposes and also to promote animals for sale. The effectiveness of this practice is determined by the relative response to selection by measuring fibre traits on a full 12 months wool staple as compared to measuring them only on part of a staple. If a high genetic correlation exists between the part record and the full record, then using part records may be acceptable to identify genetically superior animals. No information is available on the effectiveness of part records. This paper investigated whether wool growth and fibre diameter traits of Merino wool grown at different times of the year in a Mediterranean environment, are genetically the same trait, respectively. The work was carried out on about 7 dyebanded wool sections/animal.year, on ewes from weaning to hogget age, in the Katanning Merino resource flocks over 6 years. Relative clean wool growth of the different sections had very low heritability estimates of less than 0.10, and they were phenotypically and genetically poorly correlated with 6 or 12 months wool growth. This indicates that part record measurement of clean wool growth of these sections will be ineffective as indirect selection criteria to improve wool growth genetically. Staple length growth as measured by the length between dyebands, would be more effective with heritability estimates of between 0.20 and 0.30. However, these measurements were shown to have a low genetic correlation with wool grown for 12 months which implies that these staple length measurements would only be half as efficient as the wool weight for 6 or 12 months to improve total clean wool weight. Heritability estimates of fibre diameter, coefficient of variation of fibre diameter and fibre curvature were relatively high and were genetically and phenotypically highly correlated across sections. High positive phenotypic and genetic correlations were also found between fibre diameter, coefficient of variation of fibre diameter and fibre curvature of the different sections and similar measurements for wool grown over 6 or 12 months. Coefficient of variation of fibre diameter of the sections also had a moderate negative phenotypic and genetic correlation with staple strength of wool staples grown over 6 months indicating that coefficient of variation of fibre diameter of any section would be as good an indirect selection criterion to improve stable strength as coefficient of variation of fibre diameter for wool grown over 6 or 12 months. The results indicate that fibre diameter, coefficient of variation of fibre diameter and fibre curvature of wool grown over short periods of time have virtually the same heritability as that of wool grown over 12 months, and that the genetic correlation between fibre diameter, coefficient of variation of fibre diameter and fibre curvature on part and on full records is very high (rg > 0.85). This indicates that fibre diameter, coefficient of variation of fibre diameter and fibre curvature on part records can be used as selection criteria to improve these traits. However, part records of greasy and clean wool growth would be much less efficient than fleece weight for wool grown over 6 or 12 months because of the low heritability of part records and the low genetic correlation between these traits on part records and on wool grown for 12 months.
Resumo:
Airborne particles, including both ultrafine and supermicrometric particles, contain various carcinogens. Exposure and risk-assessment studies regularly use particle mass concentration as dosimetry parameter, therefore neglecting the potential impact of ultrafine particles due to their negligible mass compared to supermicrometric particles. The main purpose of this study was the characterization of lung cancer risk due to exposure to polycyclic aromatic hydrocarbons and some heavy metals associated with particle inhalation by Italian non-smoking people. A risk-assessment scheme, modified from an existing risk model, was applied to estimate the cancer risk contribution from both ultrafine and supermicrometric particles. Exposure assessment was carried out on the basis of particle number distributions measured in 25 smoke-free microenvironments in Italy. The predicted lung cancer risk was then compared to the cancer incidence rate in Italy to assess the number of lung cancer cases attributed to airborne particle inhalation, which represents one of the main causes of lung cancer, apart from smoking. Ultrafine particles are associated with a much higher risk than supermicrometric particles, and the modified risk-assessment scheme provided a more accurate estimate than the conventional scheme. Great attention has to be paid to indoor microenvironments and, in particular, to cooking and eating times, which represent the major contributors to lung cancer incidence in the Italian population. The modified risk assessment scheme can serve as a tool for assessing environmental quality, as well as setting up exposure standards for particulate matter.