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1.
Biotechnol J ; 4(10): 1441-9, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19557799

RESUMO

Enzyme technology is explored on wool fibers to prevent shrinkage and consolidation behavior during washing of woolen bed coverings using normal household machine conditions. Enzyme modification of wool fibers after two different pretreatments has been realized on industrial scale. Enlarged proteolytic enzyme by chemical modification was applied successfully to prevent substantial fiber strength loss. Felt-ball analysis of the fibers as obtained from this industrial process showed substantial improvement in felting resistance. Further processing of these enzyme-modified fibers and finally integration in bed covering quilts have been executed successfully on industrial production lines. The observed fiber losses during processing were in the range of 4.5-6% which is comparable with that of nonmodified fibers. The machine-washability of these produced bed covering quilts was tested in a household washing machine using both wool and normal wash programs applied at different temperatures. It appeared that, contrary to the good washing results in terms of shrinkage and consolidation resistance using the wool program at moderate temperatures, this resistance is marginal when washed with the normal washing program with higher mechanical agitation level or with the wool program at elevated temperature. This result was different from that obtained with woolen fabrics and explained by the less-structured organisation of fibers within a fleece.


Assuntos
Biotecnologia/métodos , Enzimas/química , Lavanderia , Lã/química , Animais , Ovinos , Resistência à Tração
2.
Biotechnol J ; 2(3): 306-15, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17219460

RESUMO

A rational approach has been applied to design a new environmentally acceptable and industrially viable enzymatic scouring process. Owing to the substrate specificity, the selection of enzymes depends on the structure and composition of the substrate, i.e. cotton fibre. The structure and composition of the outer layers of cotton fibre has been established on the basis of thorough literature study, which identifies wax and pectin removal to be the key steps for successful scouring process. Three main issues are discussed here, i.e. benchmarking of the existing alkaline scouring process, an evaluation of several selected acidic and alkaline pectinases for scouring, and the effect of wax removal treatment on pectinase performance. It has been found that the pectinolytic capability of alkaline pectinases on cotton pectin is nearly 75% higher than that of acidic pectinases. It is concluded that an efficient wax removal prior to pectinase treatment indeed results in improved performance in terms of hydrophilicity and pectin removal. To evaluate the hydrophilicity, the structural contact angle (theta) was measured using an auto-porosimeter.


Assuntos
Gossypium/metabolismo , Poligalacturonase/metabolismo , Ceras/metabolismo , Celulose/química , Celulose/metabolismo , Fibra de Algodão , Concentração de Íons de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Modelos Teóricos , Pectinas/química , Pectinas/metabolismo , Temperatura , Têxteis/normas , Ceras/química
3.
Appl Opt ; 37(36): 8306-17, 1998 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-18301653

RESUMO

Vertical profiles of atmospheric density and temperature obtained with the technique of solar refractive sounding can potentially be used to improve satellite solar occultation trace species retrievals by reducing the uncertainties associated with Rayleigh scattering and the temperature dependence of absorption bands. The required refraction measurements and the algorithm utilized to recover density and temperature are described. Simulations are performed to estimate the measurement accuracy that is necessary to retrieve useful meteorological soundings at stratospheric altitudes. The method is applied to data measured by the Stratospheric Aerosol and Gas Experiment (SAGE) II. Unfortunately, because of poor vertical sampling and measurement uncertainties, the meteorological profiles derived from the SAGE II data are not consistently accurate enough to improve the SAGE II estimates for the concentrations of trace species. However, the qualitatively decent results provide optimism for future development and implementation of visible refractive sounding as a tool to help improve the accuracy of trace species retrievals within solar or stellar occultation experiments, including the SAGE III program.

4.
Appl Opt ; 34(21): 4563-72, 1995 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-21052289

RESUMO

Calculations that use the Gauss-Seidel method are presented of the diffusely scattered light in a spherical atmosphere with polarization fully included. Comparisons are made between this method and the Monte Carlo calculations of other researchers for spherical geometry in a pure Rayleigh atmosphere. Comparisons with plane-parallel atmospheres are also presented. Single-scatter intensity comparisons with spherical geometry show excellent agreement. When all orders of scattering are included, comparisons of polarization parameters I, Q and U as well as the plane of polarization show good agreement when allowances are made for the statistical variability inherent in the Monte Carlo method.

5.
Appl Opt ; 33(9): 1760-70, 1994 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-20885505

RESUMO

A method for numerically solving the equation of radiative transfer in a spherical shell atmosphere is presented. The method uses a conical boundary and a Gauss-Seidel iteration scheme to solve for all orders of scattering along a single radial line in the atmosphere. Tests of the model indicate an accuracy better than 1% for most Earth-atmosphere situations. Results from this model are compared with flat-atmosphere model results for a scattering-only atmosphere. These comparisons indicate that excluding spherical effects for solar zenith angles greater than 85° leads to errors larger than 5% at optical depths as small as 0.10.

6.
Med Clin North Am ; 73(2): 361-71, 1989 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-2645481

RESUMO

An important role for nitrates in the treatment of patients with congestive heart failure has been demonstrated. By dilating the venous and arterial vasculature, they improve hemodynamics as well as exercise tolerance. Attenuation of nitrate action that occurs with chronic therapy can be minimized by following certain treatment strategies.


Assuntos
Insuficiência Cardíaca/tratamento farmacológico , Nitratos/uso terapêutico , Insuficiência Cardíaca/mortalidade , Insuficiência Cardíaca/fisiopatologia , Hemodinâmica/efeitos dos fármacos , Humanos , Nitratos/efeitos adversos , Esforço Físico
7.
Appl Opt ; 27(7): 1235-42, 1988 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-20531549

RESUMO

In situations where a large library of observed distributions of a function, such as temperature vs height, is available, these distributions may be used to form a set of empirical orthogonal functions. When sufficient observed distributions are not available, but when the general mathematical form of the distributions is known, a library may be constructed from the set of mathematical functions. A set of pseudoempirical orthogonal functions may then be constructed from this mathematical library. It is assumed that any distribution of the function may then be constructed from a linear sum of this pseudoempirical orthogonal set. This idea is employed to develop an inversion method using pseudoempirical orthogonal functions when a sufficient library of observations is not available. The technique employs a smoothing constraint as well as a positivity constraint, when warranted by the physical nature of the unknown.

8.
Appl Opt ; 27(7): 1243-54, 1988 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-20531550

RESUMO

The information content about tropospheric rural aerosol size distributions (i.e., functional form, accuracy of solution, and moments of the solution) that may be obtained from measurements of the backscattered radiation with no additional information is discussed. The need for additional information in the form of constraints is demonstrated. The resulting solution depends on these constraints and is thus not entirely objective. The accuracy of the solution will depend, to some degree, on the validity of the constraints. The influence of constraints is examined for the inverse problem of determining aerosol size distributions from multiwavelength measurements of backscattered radiation. Using the method of pseudoempirical orthogonal functions, two types of constraint are employed: positivity and positivity combined with smoothing. A discussion of the effects on the solutions of the two constraints is presented.

10.
Appl Opt ; 21(7): 1191-5, 1982 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-20389830

RESUMO

The dependence on bandwidth of the error in estimating both optical depth and extraterrestrial solar flux due to an assumption of Beer's law applicability across finite bandwidths is determined by a numerical integration of Beer's law across the bandwidth. It was found that for 0.1% accuracy, 100-A bandwidths suffice for central wavelengths of 0.45 microm or greater; the maximum width yielding 0.1% accuracy decreases rapidly for shorter wavelengths. The accuracy to which solar elevation angle must be known to yield 0.1% accuracy is also examined and found to be a noteworthy though noncritical effect.

11.
Science ; 214(4518): 328-31, 1981 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-17829788

RESUMO

Results of the first year of data collection by the SAM (Stratospheric Aerosol Measurement) II satellite system are presented. Almost 10,000 profiles of stratospheric aerosol extinction in the Arctic and Antarctic regions are used to construct plots of weekly averaged aerosol extinction versus altitude and time and stratospheric optical depth versus time. Corresponding temperature fields are presented. These data show striking similarities in the aerosol behavior for corresponding seasons. Wintertime polar stratospheric clouds that are strongly correlated with temperature are documented. They are much more prevalent in the Antarctic stratosphere during the cold austral winter and increase the stratospheric optical depths by as much as an order of magnitude for a period of about 2 months. These clouds might represent a sink for stratospheric water vapor and must be considered in the radiative budget for this region and time.

12.
Appl Opt ; 20(17): 2925-8, 1981 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-20333075

RESUMO

The standard technique of analyzing solar photometer data to determine atmospheric optical depth and the spectral solar constant is shown to inadvertently weight the data unequally. A new approach is proposed which equally weights all the data. Assuming that the deviations of the data points result from real random variations of optical depth during the period of the measurements, this latter approach is shown to yield more reliable results.

13.
Science ; 201(4353): 378, 1978 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-17793737
14.
Appl Opt ; 13(12): 2947-56, 1974 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-20134814

RESUMO

The Phillips-Twomey method for solving simultaneous integral equations is applied to the problem of removing blur effects arising from atmospheric and instrumental sources from astronomical observations made with photoelectric area-scanning instruments. Details of the method and the effects of observational errors on the quality of the results are discussed in the context of applications to actual observations of stars and the planet Saturn.

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