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1.
Photo-CIDNP is a useful technique to identify surface residues in proteins and to assign resonances in their 1H NMR spectra by the spectral simplification that is obtained. In spite of this simplification, conventional photo-CIDNP spectra can be quite complex due to spectral overlap. For this reason two-dimensional (2D) methods are welcome. We present combinations of photo-CIDNP with 2D J-correlated spectroscopy (CIDNP-COSY) and with 2D NOE spectroscopy (CIDNP-NOESY). In these experiments we insert a saturation pulse sequence and a short laser-irradiation period at the beginning of the preparation period to generate CIDNP, leaving the remaining of the pulse scheme essentially unaltered. The CIDNP-COSY and CIDNP-NOESY spectra of a hen egg-white (HEW) lysozyme are presented. The CIDNP-NOESY spectrum of lysozyme is compared with the results from 1D cross-polarisation experiments on the same protein. CIDNP-NOESY spectra of lysozyme with and without inhibitor NAG are compared.  相似文献   
2.
An advanced x-ray diffraction technique allows the development of texture components to be monitored and provides supplementary information about the cold work and residual stresses in cold-rolled copper sheet. The new technique confirms the results of an ultrasonic test, except for the ultrasonic test’s sensitivity to grain size. The new x-ray diffraction technique could be adapted to provide in-process, nondestructive evaluation of thin copper sheet, even for material moving at high speeds.  相似文献   
3.
This paper determines the optimal timing of dike heightenings as well as the corresponding optimal dike heightenings to protect against floods. To derive the optimal policy, we design an algorithm based on the Impulse Control Maximum Principle. In this way, this paper presents one of the first real-life applications of the Impulse Control Maximum Principle developed by Blaquière. We show that the proposed impulse control (IC) approach performs better than dynamic programming with respect to computational time. This is caused by the fact that IC does not need discretization in time.  相似文献   
4.
Most one-dimensional soil moisture flow simulation models have restricted applicability due to (amongst other things): i) insufficient user flexibility; ii) a lack of user friendliness; iii) dependency on scale, temporal and/or spatial, and iv) fixed boundary conditions. Therefore, we developed a simple and highly flexible software package to simulate, visualize and analyze 1-D moisture flow in soils: SoWaM (Soil Water Model). The package has a modular setup and consists of a range of tools to visualize, analyze and compare input data and results. Soil hydraulic properties for each specified soil layer can be defined by either Van Genuchten parameters or cubical splines. Since the model does not impose limits on element size or time interval, it is possible to perform simulations in very high detail, both spatially and temporally. Furthermore, four different criteria for irrigation scheduling have been implemented. The SoWaM package provides an accurate, simple and highly flexible tool to simulate soil moisture flow and to evaluate the effects of various factors on soil water movement, such as timing and amount of irrigation, soil hydraulic properties and soil layering. Results of a case study are presented to illustrate model performance.  相似文献   
5.
The amount of information available to information workers recently has becomeoverwhelming. This confronts information workers with two majorproblems: finding the information needed, and accessing it; they arecalled the search problem and the access problem, respectively. Asthe main result of our research an architecture is specified of anautomated tool that provides integrated support for searching andaccessing multimedia documents that may be located at arbitraryplaces. The architecture contains a database with information aboutthe documents and with thesaurus-like information. The architecturealso contains a browse mechanism and a query mechanism for inspectingthe database. In the design process of the architecture, severalfundamental questions arose, like “What is a document?”and “ What is a medium kind?”. The developed answers tosome of these questions are considered to have a general characterand thus to be useful also outside the scope of the research at hand.The paper concludes with an overview of the current status of theproject and a discussion of future work.  相似文献   
6.
Investigations on Potato Pulp as a Dietary Fiber Source. Composition of Potato Pulp After Influence of Pectinases and Cellulases and Enzymatic Degradation of Starch. The composition of alcohol insoluble substances (AIS) of potato pulp have been investigated after succesive degradation with different pectolytic and cellulolytic enzymes followed by starch degrading enzymes. The pretreatment with pectinase/cellulase combinations has a significant influence on the amount and the properties of the residues after starch degradation. Furthermore the most important changes in the composition were found in the receiving residues after action of amylolytic enzymes. A correlation exists between the content of residual starch in the residues and the action of the cell wall degrading enzymes. The amount of residual starch correlates negatively with the intensity of cell wall degradation. The enzymatic susceptibility of starch depends on the damage of cell wall of potato pulp, especially on the degree of degradation of the cellulose. The water binding capacity decreases intensively after action of pectinase/cellulase combinations. The treatment with amylolytic enzymes causes only a negligible variation of the water binding capacity.  相似文献   
7.
Small-scale food fermentation technologies in developing countries have evolved through years of experience rather than through scientific breakthroughs. Many small-scale manufacturers are, therefore, reluctant to accept change and modify fermentation processes. Upgrading the quality and safety of fermented foods, while reducing their production cost and maintaining their authenticity and uniqueness, is of utmost importance. One strategic approach, which has been successfully implemented for the improvement of small-scale soy sauce fermentation in Thailand, is the consortium approach. This approach has allowed industry to work closely in sharing knowledge and common problems, which in turn has provided scientists with the research direction that would best benefit the industry. This consortium approach has brought about changes in the methodologies used in the production of soy sauce, by shortening processing times, introducing fiberglass tanks as bioreactors instead of the traditionally used small earthenware containers and introducing cost-effective waste management systems. One barrier to the application of starter cultures in the small-scale fermentation industry is the loss of uniqueness of fermented products. However, the advent of molecular biology techniques has allowed science to tailor starter cultures to the specific requirements of the manufacturer. Using the techniques of molecular biology, it has been shown that microflora of a specific product vary according to origin and sensory quality. A cell bank is being developed to serve as a resource base for Thai fermented pork sausage in order to facilitate the application of starter cultures in the manufacture of that product.  相似文献   
8.
The conscious experience of self-agency (i.e., the feeling that one causes one’s own actions and their outcomes) is fundamental to human self-perception. Four experiments explored how experienced self-agency arises from a match between nonconsciously activated outcome representations and the subsequent production of the outcome and explored specifically how implicit motivation to produce the outcome may impinge on this process. Participants stopped a rapidly presented sequence of colors on a computer screen. Subsequently, they were presented with what could be the color on which they had stopped the sequence or a color that was randomly chosen by the computer. Agency ratings after each trial revealed that priming outcomes (a specific color) just before the outcome was produced enhanced experienced self-agency. Importantly, priming outcomes relatively far in advance also augmented self-agency, but only if the outcome was attached to positive affect and thus operating as a nonconscious goal maintaining the outcome representation active over time. As such, these studies show how the mechanisms underlying nonconscious goal pursuit promote experiences of self-agency, thus integrating 2 lines of research that so far have led separate lives. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
9.
Failure mechanisms were determined for electron-beam physical-vapor-deposited thermal barrier coating (TBC) systems from the degradation of mechanical properties and microstructural changes in a furnace cycle test. Bond strength degradation for TBCs resulted from the initiation and growth of interfacial delamination defects between the yttria-stabilized zirconia topcoat and the thermally grown alumina (TGO). It is proposed that defects started from concave depressions in the bondcoat surface created by the grit-blast-cleaning process and that defect growth was driven by the reduction in compressive strain in the TGO as the alumina deformed into and displaced the bondcoat during the cooling cycles. Inclusion of yttrium in the substrate resulted in a doubling of the furnace cycle life of the TBCs because of enhanced fracture toughness of the TGO-bondcoat interface.  相似文献   
10.
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