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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.
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   

13.
An annotated list is presented describing seventeen periodicals that cover significant aspects of the gay, lesbian, bisexual, and transgender (GLBT) community and their culture in whole or in part, with popular content rather than an academic or research focus. The titles included are a selective and representative sampling. The entry for each periodical includes the following information: periodical title, publisher/editor and address, basic information, publication data, content, Internet information, an abstract/annotation, and evaluative statement  相似文献   

14.
SUMMARY

The state of Illinois funded a large scale Ariel project. This is a report of the project's successes and shortcomings. Although widely successful, additional training in the use of sophisticated hardware, primarily Minolta scanners, is needed. Data on sending and receiving is included.  相似文献   

15.
SUMMARY

Ariel files are the starting point for electronic delivery of interlibrary loan articles through ILLiad, Virginia Tech's interlibrary loan system. Despite some advantages to electronic delivery of articles to their desktops, a large majority of ILL customers continue to prefer print on paper delivery rather than electronic delivery. This fact has implications for introducing additional electronic services. Correctly choosing what services to impose on library customers, and what services to offer as value-added options, is fundamental to maintaining the credibility of libraries during these times of rapid change.  相似文献   

16.
SUMMARY

The authors discuss the development of the Slovak periodical press within its historical context and their expectations for its future. The article covers general characteristics of Slovak magazines and newspapers from World War II to 1989, and their later development since the Velvet Revolution up to the present. It also discusses the Slovak press outside of Slovakia from the late nineteenth century.  相似文献   

17.
SUMMARY

There are between fifteen and twenty U.S. libraries that collect publications from Central Asia, defined here as Kazakhstan, Kyrgyzstan, Tajikistan, Turkmenistan and Uzbekistan. Collection development responsibility for these countries tends to rest with the Slavic selector, the Middle East selector, or both, divided by language. Vendors who can supply this material mostly also supply publications from other countries of the former Soviet Union. The author briefly discusses the history of collecting from this region and the results of a survey conducted in 2004. She presents evidence indicating that the main reason U.S. libraries are not receiving more books from the region is most likely because they are not being published, not because vendors are doing an inadequate job.  相似文献   

18.
Library Journal's 2011 Ebook Penetration and Use in U.S. Libraries Survey testifies to e-books’ increasing popularity in academic libraries. This review tracked literature published from 2005 that focused on academic librarians’ best practices for acquiring, cataloging, maintaining, and promoting e-books at their institutions. Some of these practices include implementing trial accesses, considering institutional requirements, providing an e-book presence in the library catalog, monitoring usage statistics, and utilizing the library Web site for promotional efforts.  相似文献   

19.
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   

20.
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