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211.
Polarography     
J Heyrovsky’s invention of polarography in which a dropping mercury electrode is used in the electrochemical cell revolutionised electroanalysis, study of electrode kinetics and adsorption studies on mercury electrodes. Polarography has also directly contributed to the development of new and innovative ideas in electrochemical techniques, instrumentation and applications  相似文献   
212.
Previous attempts to examine the effects of different types of text format on reading have focused on the improvement of reading. The present study investigated the effect of using a text format that might be predicted to disrupt reading. In this study 56 individuals were presented with reading material presented in right-justified format and in'ragged'uneven line format. Subjects performed significantly worse on right-justified material. Subjects who were classified as good readers on the basis of a pretest were more affected than poor readers. It is suggested that this may result from differences in the reading style of good and poor readers.  相似文献   
213.
Methods for identifying students with learning disabilities continue to be an area of controversy. The present investigation examined the impact of implementing statewide guidelines for the identification of these students. Data were collected from multidisciplinary team reports on 718 students with learning disabilities who were referred and labeled during the 1983-84 school year (before implementation of statewide learning disability guidelines) and 790 students who were identified during 1987-88 (after implementation of the guidelines). The results of the study revealed that the statewide guidelines significantly changed the characteristics of students who were identified. After the implementation of the guidelines, students with much more severe academic problems were identified. These students were much more likely to have a severe discrepancy and be chronically failing in the regular classroom. However, even with explicit, widely accepted guidelines, approximately one third of all students identified in 1987-88 failed to meet the stated criteria for identification. The implications of these findings for professional practice and future research are discussed.  相似文献   
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A great number of Central Asian wall paintings, archeological materials, architectural fragments, and textiles, as well as painting fragments on silk and paper, make up the so called Turfan Collection at the Asian Art Museum in Berlin. The largest part of the collection comes from the Kucha region, a very important cultural center in the third to ninth centuries. Between 1902 and 1914, four German expeditions traveled along the northern Silk Road. During these expeditions, wall paintings were detached from their original settings in Buddhist cave complexes. This paper reports a technical study of a wall painting, existing in eight fragments, from the Buddhist cave no. 40 (Ritterhöhle). Its original painted surface is soot blackened and largely illegible. Grünwedel, leader of the first and third expeditions, described the almost complete destruction of the rediscovered temple complex and evidence of fire damage. The aim of this case study is to identify the materials used for the wall paintings. Furthermore, soot deposits as well as materials from conservation interventions were of interest. Non-invasive analyses were preferred but a limited number of samples were taken to provide more precise information on the painting technique. By employing optical and scanning electron microscopy, energy dispersive X-ray spectroscopy, micro X-ray fluorescence spectroscopy, X-ray diffraction analysis, and Raman spectroscopy, a layer sequence of earthen render, a ground layer made of gypsum, and a paint layer containing a variety of inorganic pigments were identified.  相似文献   
217.
In 2013, The Better Image (TBI) was contacted to examine A Play of Selves, a unique work created by artist Cindy Sherman during her graduate studies in 1975. The work is composed of 244 paper doll-like photographs of Sherman that are presented within 72 frames. During initial condition checks, it was noted that a number of individual elements had begun to show signs of chemical staining. Over the course of 2013/2014, a collaborative response was developed with the help of the artist, the artist's printer, the representing gallery, TBI staff and the owner. The main goal was to address the physical and chemical issues present and preserve this work for future exhibition and study. Determining an effective decision- making model based on a hierarchy of values was crucial before undertaking any conservation treatment, as there were several invested parties, each with a different perspective. The focus of this paper is the interplay of our responsibilities as conservators with the concerns of the artist, her gallery, her printer, and the owner to balance aesthetic vs. physical integrity of the artwork, reversibility of treatments, importance of record keeping while developing a balanced response within a world of rapidly disappearing traditional photographic papers.  相似文献   
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Though there is a long tradition of band members quitting the group or taking a hiatus, the rock group as an organization to produce music continues to be both popular and economically viable. The research question addressed in this paper is whether or not it is a good idea to quit or take a hiatus from the group. We begin with a discussion of the framework for understanding why groups are formed and why they may be difficult to keep together. We then discuss differences between groups in the decade of the 1960s versus today. We argue that there is something unique about the output of the group even with the changes in the structure of contracts, compensation, and consumer focus on the artist that explain the resilience of the rock band as an organizational form within which to create music. We compare the charting success of bands that have members leave the group with the charting success of the members who left the group. We identified the groups in five representative years: 1965, 1975, 1985, 1995, and 2005. We then analyzed the entire Billboard Hot 100 charting careers of those groups and the artists who quit those groups. Our main finding is that when charting success is divided equally among members, going solo pays off—there is a clear economic rationale because solo acts have greater average charting success than the original bands they started in. The other ensuing side projects: duos, collaborations, and other groups are not as lucrative as the original bands. These findings are valid for members of charting groups from each of the 5 years examined. Despite the difficulties in keeping a rock band together, there are fewer band breakups today and remaining with the group generally results in a longer and more productive charting career. Thus, the rock group remains an important organization for producing contemporary music. However, there remains a compelling incentive to go solo. Superstars may benefit from solo projects, but for the average, non-superstar group member, in many circumstances it is better for the band to stay together if the income is divided equally.  相似文献   
220.
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