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121.
This study examined the influence of soft-money-sponsored issue-advocacy advertising in U.S. House and Senate campaigns, comparing its effects against candidate-sponsored positive advertising and contrast advertising on viewers' candidate preferences and on their attitudes that reflect democratic values. The results revealed no main effects for advertising approach on candidate preference. Instead, advertising approach exerted unique impacts based on viewer party affiliation: Advocacy ads influenced only nonpartisans, whereas candidate-sponsored contrast advertising primarily affected Republicans. Viewer exposure to candidate-sponsored advertising, both positive and contrast, elicited greater viewer awareness and interest in campaigns and more knowledge of the candidates and their positions, both in comparison to the control condition and to soft-money-sponsored issue-advocacy ads.  相似文献   
122.
This work aims to study the parameters that affect the micro hole machining process (diameter smaller than 0.1 mm and thickness/diameter relation bigger than 20), by electro-erosion penetration process in sheets. To make the execution of the micro holes in conventional machines possible, the construction of two devices is proposed, a mechanical and an optical one. From results experimentally obtained, the process proved to be technically and economically viable, mainly if compared with mechanic drilling, as it presents advantages when cost per tool, number of holes per tool, drilling length, and precision of the holed dimension are considered. The circularity deviation provided by the experiment was smaller than 0.01 for 0.1 mm diameter holes made in 2.4 mm thick SAE 1010 steel sheets. It was also concluded that the quality of the hole directly depends on the cleaning process.  相似文献   
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A fracture control technique for composite structures is presented which takes advantage of the unique capability of composite materials to be tailored in stiffness and fracture toughness. Crack arrestment is achieved through the use of integral ‘buffer’ strips in the primary load-carrying laminate. Experimental uniaxial tension data obtained from damaged laminates containing such buffer strips indicate residual strength capacity in excess of the limit design stress for the selected laminate.  相似文献   
125.
Jacek Kaminski   《Applied Energy》2003,75(3-4):165-172
The emissions limits, which are currently harder to meet than a few years ago, foster energy sector entrepreneurs to consider the possibilities of economically efficient emissions-reductions at their power plants. Within this paper the main methods of sulphur dioxide reduction will be described. The second problem considered in this paper is related to the economic aspect of emissions reduction. The choice of the method is often based on the comparison of costs associated with the appropriate methods. Therefore, for the technologies described, the average reduction costs will be presented and the most efficient way will be highlighted.  相似文献   
126.
Sustainable management of mineral nutrition in vineyards, as well as in other fruit plantations, should aim at exploiting the use of internal sources of nutrients, in order to reduce the need for external nutrient inputs. In this paper we explore the potential of the grassed alleys to provide nutrients to the vines. We followed for one vegetative season the decomposition of ryegrass and clover, frequently present as floor vegetation in vineyards, using litter bags filled with 15N-enriched grass material. In addition, we quantified the amount of nitrogen (N) transferred from the decomposing litter to field-grown grapevines. Ryegrass and clover had a relatively rapid decomposition rate, with a loss of C approaching 80% in only 16 weeks. The release of nutrients was particularly fast for potassium (95% in 16 weeks) followed by nitrogen (80%), calcium (70–80%), phosphorous (65–85%), magnesium (70–75%), and sulfur (60–70%). In spite of the rapid release of N from decomposing material, the N uptake by grapevines was on average less than 4% of the initial amount of N present in the litter of ryegrass and clover. Even if N release during the decomposition of mowed perennial ryegrass and white clover little contributed to the N nutrition of grapevine in the same growing season, most N from mowed grassed was still recovered in the soil.  相似文献   
127.
The organization and implementation of a stability program for marketed batches is addressed by answering the questions: (1) What is a stability program?, (2) Why are stability programs necessary?, and (3) How do we conduct the program? Comments will be made regarding historical considerations and remarks will be directed toward the tools that are necessary for the program. There is no documented cookbook describing how to organize and perform your stability program. There are indications however, and these will be incorporated into a discussion of how one program is being used.  相似文献   
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129.
Parenteral hyperalimentation, when used free of associated morbidity, usually produces a dramatic reversal in the deteriorating clinical course of the patient. However, most patients who need nutritional support have at least a minimally functioning gastrointestinal tract. By using a continuous enteral gavage of a chemically defined diet through a 4F tube, the same positive nitrogen balance, weight gain and accelerated wound healing can be achieved. As with parenteral hyperalimentation, there are avoidable iatrogenic morbidities. A policy and procedure for safe and effective enteral hyperalimentation, results of clinical experience and a simplified method for assessing achievement of a therapeutic goal are presented.  相似文献   
130.
Abstract— A low‐temperature amorphous‐silicon (a‐Si:H) thin‐film‐transistor (TFT) backplane technology for high‐information‐content flexible displays has been developed. Backplanes were integrated with frontplane technologies to produce high‐performance active‐matrix reflective electrophoretic ink, reflective cholesteric liquid crystal and emissive OLED flexible‐display technology demonstrators (TDs). Backplanes up to 4 in. on the diagonal have been fabricated on a 6‐in. wafer‐scale pilot line. The critical steps in the evolution of backplane technology, from qualification of baseline low‐temperature (180°C) a‐Si:H process on the 6‐in. line with rigid substrates, to transferring the process to flexible plastic and flexible stainless‐steel substrates, to form factor scale‐up of the TFT arrays, and finally manufacturing scale‐up to a Gen 2 (370 × 470 mm) display‐scale pilot line, will be reviewed.  相似文献   
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