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1.
《文物保护研究》2013,58(1):23-29
Abstract

Upon aging, paper documents and books become progressively damaged. Paper deacidification is a fundamental conservation intervention. In this study, we report on the use of nanoparticles of titanium dioxide (TiO2) and magnesium hydroxide (Mg(OH)2) associated with hydroxyethylcellulose (HEC) to inhibit acidification, photo-induced degradation, and biodeterioration of paper. With the aid of ultrasound, Mg(OH)2 nanoparticles with a narrow size distribution can be obtained through homogeneous precipitation in water. Furthermore, to demonstrate the efficacy of the nanocomposite and the performance of treated and untreated paper, photo- and thermal-induced degradation is discussed. The results show that using the controlled double-jet precipitation (CDJP) it is possible to synthesize Mg(OH)2 particles with a narrow size distribution (18–87 nm). The nanocomposite of Mg(OH)2–TiO2–HEC increases the durability of paper by imparting fungal growth resistance (D = 34.6 mm), moderate alkalinity (pH = 8.4), mechanical reinforcement (from 817–896 N/m), and UV protection. Additionally, there is a slight color difference (ΔE* = 0.8) between the treated and untreated paper. Both photodegradation and thermal degradation indicate that the paper treated with this nanocomposite (Mg(OH)2–TiO2–HEC) has increased stability.  相似文献   

2.
A new coating system for archeological bronze protection that consists of a primer coating and a top coating was prepared in this study. The primer coating was prepared by mixing water-based acrylic emulsion with 1,2,3-benzotriazole, and the ultraviolet (UV) light-resistant top coating was prepared by mixing water-based acrylic emulsion with nano-sized TiO2 and SiO2 particles. UV light resistance and visible light transmission, contact angle, corrosion resistance, and mechanical properties of the new coating system were investigated and the results showed that UV resistance, hydrophobicity, oleophobicity, glossiness, and corrosion resistance all were improved. Application of the new system on real archaeological bronzes showed that the coating film was colorless, odorless, transparent, soft low-lustre, removable, and the original appearance of the archaeological bronze was well maintained.  相似文献   

3.
Online Updates     
No abstract available for this article.  相似文献   

4.
ABSTRACT

Calcarenite stone samples from a historic building (Bizerte, Tunisia) were collected and treated under different environmental conditions with several consolidating products: alkoxysilane (ethyl silicate), a surfactant-templated novel sol–gel, Ca(OH)2, and SiO2 nanoparticles. These were subjected to marine aerosol accelerated aging cycles and studied by several non-destructive tests and techniques to assess the stability of the products. Results show that weathering caused by salt crystallization is not inhibited but it is slowed down due to the enhancement of superficial mechanical properties (surface cohesion and micro-hardness) achieved after one month of treatments application. A high or low relative humidity of the consolidation environment significantly affects the final mechanical and aesthetical physical properties and therefore conditions the durability of the treated substrates, even producing higher damage than observed in the blank specimens, depending on the product.  相似文献   

5.
ABSTRACT

A decontamination treatment using liquid CO2 (li-CO2) and specifically developed for the requirements of museum objects (Lombardo, T., M. Wörle, V. Hubert, E. Hildbrand, I. Mayer, C. Hinterleitner, U. von Arx. 2020. “Influence of Process Parameters on Chlorinated Biocide Decontamination by li-CO2 on Artificially Contaminated Model Materials.” Studies in Conservation, in press, doi:10.1080/00393630.2019.1641001) was first tested on model materials of wood (with and without coating), silk, and wool with different dyes, paper, and leather in order to evaluate possible material changes. Then, selected museum objects from the collection of the Swiss National Museum were treated to determine the efficiency of biocide decontamination and any resulting chemical and/or structural changes. Results show that dichlorodiphenyltrichloroethane (DDT), pentachlorophenol (PCP), lindane, and chlorpyrifos were successfully removed. Wool, silk, leather, and non-coated wood did not experience any detectable modifications, while moderate to major modifications were observed in wood coated with shellac and polychromy.  相似文献   

6.
《Communication monographs》2012,79(2):252-270
This study surveyed German heterosexual men's interest and engagement in a variety of dominant behaviors observed in recent analyses of pornography. Interest in watching popular pornographic movies or more frequent consumption of pornography was associated with men's desire to engage in or having already engaged in behaviors such as hair pulling, spanking a partner hard enough to leave a mark, facial ejaculation, confinement, double-penetration (i.e. penetrating a partner's anus or vagina simultaneously with another man), ass-to-mouth (i.e. anally penetrating a partner and then inserting the penis directly into her mouth), penile gagging, facial slapping, choking, and name-calling (e.g. “slut” or “whore”). Consistent with past experimental research on the effect of alcohol and pornography exposure on men's likelihood of sexual coercion, men who had engaged in the most dominant behaviors were those who frequently consumed pornography and regularly consumed alcohol before or during sex.  相似文献   

7.
Transmedia is a technique of telling a single narrative or creating a continuous imaginary world across multiple media platforms. The article seeks to explore this emerging phenomenon in terms of bibliographic organization. It analyzes transmedia features in the context of bibliographic entities and relationships, particularly those outlined in the Functional Requirements for Bibliographic Records FRBR and FRBROO (object-oriented redefinition) conceptual models.  相似文献   

8.
ABSTRACT

Previously, heavy use of biocides for the treatment of objects made of organic materials in museum collections (e.g. ethnographic, historical collections) was very common. Now suitable decontamination methods/technologies are being sought. A decontamination treatment by li-CO2 was optimized that considered the specific requirements of museum objects. The treatment was tested on model materials artificially contaminated with biocide solutions containing dichlorodiphenyltrichloroethane (DDT), pentachlorophenol (PCP), lindane, and permethrin or cypermethrin. High decontamination was achieved for DDT, lindane, PCP, and permethrin on artificially biocide loaded wool and wood model materials. Optimal process parameter settings for li-CO2 decontamination include a single 30?min cycle for woolen materials and three sequential 30?min cycles each for wood. These methods allow a reduction of at least 90% of all biocides for wool and between 70% and 85% for wood. Decontamination of the latter was more effective for less polar biocides as DDT and permethrin. Despite a significant improvement in decontamination for wood using co-solvents such as acetone, ethanol, and methyl tertiary-butyl ether (MTBE), their use is not recommended due to the increased risk of damage to the objects, in particular if a surface coating is present.  相似文献   

9.
ABSTRACT

The surface texture of a stone represents a sensitive parameter in evaluating its conservation state. In monuments and sculptures, in fact, external agents continuously alter the appearance of stones, determining peculiar weathering patterns and modifying properties such as retention of water and particles, interaction with light, color, and finishing. The application of protective coatings also determines changes in surface appearance of a stone, usually evaluated and monitored by color change tests. Surface metrology methods offer the possibility to quantify these changes, evaluating the impact of external agents (natural, i.e. weathering, and artificially, i.e. protective coatings) on natural stones. In this research, we demonstrate the potential of surface areal measurements in describing the evolution of weathering processes and the effects of protective treatments on porous stone materials. The obtained results suggest that the extent of the modifications is related to the scale of observation (small- vs. large-scale undulations, i.e. roughness and waviness, respectively), with an overall increase of surface roughness as the weathering proceeds. Unexpectedly, coatings based on nanoparticle dispersions increase the topographic height parameters, due to the absence of a homogeneous film.  相似文献   

10.
ABSTRACT

The article examines the most important periodicals of ethnic minorities in Poland. After 1989, many ethnic groups (e.g., Germans and Romanies) were allowed to publish journals and newspapers for the first time since the end of World War II. The publications examined show the rich cultural life of the various ethnic groups as well as their current status in Poland. In addition to popular titles, some scholarly publications are also discussed.  相似文献   

11.
The author answers a reference question on bibliographic sources for the Ukrainian periodical press 1840–1850. Helpful publications include bibliographies, guides, and library catalogs. These potentially make mention of revolutionary developments in Hungary (such as the Twelve Points paragraph of the Demands of the Hungarian Nation in March 1848, the subsequent April Laws, and Hungary's declaration of independence in April 1949), and elsewhere in the Hapsburg Empire.  相似文献   

12.
The author describes the Slavic Humanities Index, a bibliographic database of scholarly and cultural articles on subjects including history; literature; language teaching; linguistics; philosophy; ethnology; performing arts; and cultural, borderland, and regional studies. She discusses its development, its current form and functionality, and plans for the future.  相似文献   

13.
SUMMARY

This article discusses Jewish book publishing in most of the Soviet Union's successor states after 1990. All publications on Jewish history, culture, traditions, and religion (Judaism) are included under this rubric. In addition to scholarly and educational publications, fiction translated from Yiddish and Hebrew, and “Russian-Jewish literature” are also included. The author provides statistics and discusses basic themes, linguistic issues, and problems encountered in the post-Soviet states. The article lists different publishers and organizations involved in Jewish book publishing.  相似文献   

14.
This article describes a study of the two most popular plagiarism-detection software platforms available on today's market—Turnitin (http://www.turnitin.com/static/index.html) and SafeAssign (http://www.safeassign.com/). After a brief discussion of plagiarism's relevance to librarians, the authors examine plagiarism-detection methodology and conduct a review of the current literature regarding plagiarism-detection efficacy. To evaluate detection efficacy for Turnitin and SafeAssign, the authors constructed a brief study in which twenty sample papers containing portions of plagiarized material were submitted to each platform. The results show that Turnitin had the highest overall success at plagiarism detection with an 82.4 percent detection rate. Additionally, both platforms had a combined false-positive detection rate of 16.8 percent. The authors conclude that close review of material suspected of plagiarism is still essential for proper identification.  相似文献   

15.
本文选择了国内外几个典型的引文数据库,如:美国《艺术与人文科学引文索引》、《社会科学引文索引》、中国的《中文社会科学引文索引》、《中国科技论文引文分析数据库》、中国科学引文数据库等,并对其收录范围、来源文献的学科分布、更新频率等方面进行了比较研究,对今后我国引文数据库的建设提出了一些建议。  相似文献   

16.
ABSTRACT

The article describes the development and use of the database BAZTECH: Polish Technical Journal Contents. The database indexes Polish-language scientific and technical journals, and is available free-of-charge on the Internet.  相似文献   

17.
Abstract

The Russian government is exerting increasing control over the country's media, although the media are resisting. This government-media conflict is relevant to Western academics and libraries, because the variety and quality of Russian periodicals is at stake. In addition, if the media are constrained, publishers of books are likely to experience restrictions, too. The difficulties the government is having in controlling the media, however, are a measure of how much Russia has changed. At the same time this conflict is occurring, book publishing is thriving. Official statistics show the number of titles published surpassed even the previous record set in 1977. Planning is in progress to restructure the state book industry sector, including publishing, printing and distribution. Book prices have increased more rapidly than inflation, and postage costs have also increased. Russian Press Service is doing its best to keep its prices to Western libraries down.  相似文献   

18.
SUMMARY

Describing her experience of establishing an Electronic Document Delivery Service at the library of the Lahore University of Management Sciences (LUMS), the author discusses the various issues, which significantly effect the net cost, delivery time and management process of providing such a service by a library in Pakistan. While presenting multiple options leading to an effective solution, the advantages and disadvantages of each option have been highlighted, and their implications, with particular reference to Pakistani libraries, have been discussed. The various points to be considered by Pakistani Librarians, while selecting a commercial Document Provider, have also been discussed. In the end, the author discusses the potential of using the Electronic Document Delivery facility as a time-saving and cost-effective tool for Resource Sharing among libraries in Pakistan.  相似文献   

19.
ABSTRACT

No one can predict what document delivery will look like in the future, but librarians must guard patron confidentiality even in an electronic environment. This time it isn't an easily solved problem like finding another way of recording circulation than handwriting patron names onto circulation cards, it is instead the tracking of personal information attached to electronic text supplied by publishers that is a potential violator of patron privacy. Unmonitored in their efforts to protect their intellectual property without considering the rights of their customers, publishers could pose a threat to their customers' privacy, thus limiting their legal right of free access to information. Although encryption technology would appear to provide an answer to the confidentiality problem, it is not a panacea and that must be considered as the National Information Infrastructure is developed. Librarians need to stay alert to the developments in electronic publishing to be sure their concerns for patron privacy continue to be heard.  相似文献   

20.
Most studies of collection development mask inadequate theoretical underpinnings with facile assumptions and dazzling statistical manipulations. This essay, in moving toward a model for collection development within both specific collections and library systems as a whole, seeks to demonstrate the full range and complexity of relevant factors. An enlarged theoretical grasp should help highlight both the possibilities and the challenges of existing approaches. One result could be a shift toward gaming or simulation techniques as more realistic analytical tools.  相似文献   

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