Abstract:Removal of paintings from old backings is the most critical step in the process of remounting the paintings. The paste used in the process of mounting often makes it hard to separate the painting itself from the support paper. As a consequence, the removal process is very complex and easy to result in damage of ancient paintings and calligraphy. In the traditional method of removal, the object is moistened with water for a long time in order to reduce the viscosity of the paste, and then a conservator use his/her fingers to gently twist the support paper, making possible removal of the old support paper and paste from the back of the painting. In the present study, the extracellular fluid of Bacillus fermentation was used to make a biological removal agent. The effectiveness of the agent on the aged cotton paper was tested. The results showed that the biological agent obtained by using the fermentation broth of Bacillus subtilis, after dialysis to eliminate bacteria, had good effectiveness. The safety of using a biological agent to remove paintings was tested by scanning electron microscopy and tensile strength analysis. It is found that the biological agent can reduce the peeling force and fiber index, increase the tensile strength of paper samples, compared to water moistening, and has no significant effect on the paper microstructure. The agent improves the safety of removing backing papers. Good results have been achieved on treating a complete set of Ming Dynasty land and water paintings.

Abstract:Serious decay and interlayer adhesion are commonly found on longburied textiles of cultural heritage interest. An unfolding reagent based on the concept of selfstratification was developed. The reagent can reduce the intensity of interlayer adhesion, as well as increase the mechanical strength of the textile. Atomicforce microscopy and scanning electron microscope were used to characterize the filmforming ability and permeability of the unfolding reagent. The reagent was further assessed by measuring the mechanical strength, chromatic aberration and stiffness of the textiles treated. This reagent was then shown to be an excellent for unfolding and reinforcing the fragile textile. The reagent was used successfully to unfold a fragile Song dynasty textile unearthed at Nanling, Anhui.

Abstract:The repair of ancient books is a cultural activity of great significance. Prior to the actual restoration, a lot of care needs to be taken to determine the historical background of the book, to analyze the cause of decay and to think about the level of restoration to the book’s original physical status. At the same time, the readability of the book to library readers should be considered to some extent. Based on principles of “minimal”, “reversible ” and “identifiable” types of intervention, some protective restoration methods that might be applied to a Qing dynasty volume in the Central National Library of Italy were explored. The methods applied in the restoration process include paper deacidification, wetcleaning of surfaces, stiffening, repair of lacunae, rebinding, case making and preservation of the original binding line that has to be removed. Those methods are aimed at preserving the maximum faithfulness as well as the maximum culturalhistorical significance of the book. This study describes some new methods and some new thoughts for colleagues in China.

Abstract:Hyperspectral imaging technology is an efficient and nondestructive technique to study ancient Chinese paintings. The method is not affected by test objects and environment. A hyperspectral imaging system to scan and analyze some paintings in the Palace Museum was developed. It is found that this method has unique advantages in studies of text information enhancement, extraction of hidden information,extraction of line features from drawings, and that it benefits identification of colors and classification of paintings. The number of ancient paintings is very large in the Palace Museum.These paintings need to be well conserved and restored. Hyperspectral imaging technology can be applied in Chinese paintings conservation. It provides a safe and effective approach for scientific analysis and conservation.

Abstract:With the development of underwater archaeology in China, scientific conservation of underwater cultural relics becomes more and more important. It is difficult to remove the different kinds of attachments on the surface of underwater porcelain. Current mechanical and chemical methods have their own limitations. Due to its long existence time, high mass transfer efficiency and high zeta potential of surface charge, micronano bubble cleaning technology has shown great effectiveness on underwater porcelain in cleaning tests. This makes it essential to evaluate its safety in the next stage. Eighteen porcelain shards samples from the Nanhai I shipwreck were selected for the evaluation. Condition survey and diagnostic analysis were made, colorimetric analysis, gloss analysis, microscopic analysis and microscopic measurements were used. The results gave no indication that micronano bubble cleaning would lead to the change of color or gloss of underwater porcelain. No damage was detected on the glaze, and there was no change in existing cracks on the surface of the porcelain. The current evaluation results show that micronano bubble cleaning is safe for underwater porcelain, which provides important support for the application of this technology to the actual conservation of cultural relics.

Abstract:The dynamic response of cultural showcases under seismic and simple harmonic excitation is described in this paper. The upper limit of the acceleration magnification coefficient of the booth surface was determined for the fixed and floating showcases. First, the vibration experiments according to 1∶1/0.39 of a museum exhibition shelves were carried out to obtain the amplification coefficient of the surface of the showcase booth under two kinds of boundary conditions. The simulated results were compared with the experimental data to verify the correctness of the finite element model and analysis method. Second, the finite element model of the prototype was established in order to consider the influence of the excitation amplitude and excitation frequency on the amplification coefficient of the five sizes of showcases. These research results will help to direct the work for protection of cultural relics.

Abstract:Different materials have different absorption characteristics, so their spectral reflectances have different characteristics. In order to analyze the pigments of Dunhuang murals, an algorithm was designed to recognize pigments automatically based on extracted features of their visible reflectance spectra. The first and second order derivative of the visible reflectance spectrum in the range 400~700nm was computed to extract peak information. The absolute value of the negative position in second order derivative was selected as feature data to present the peaks. A median pyramid was used to derive three resolution representations of the featured curves to enhance the most important information, and then these three curves were normalized and combined as the feature space F.The Euclidean distance between sample points and pigments database was calculated as the similarity to identify the mineral pigment of target color points. Results show that the nondestructive identification method can recognize the pigments of Dunhuang murals efficiently and accurately. The method is worth applying to the restoration and digital archiving of murals.

Abstract:Portland cement has been utilized in the protection of historical sites. However, this usage is always controversial due to the high strength of the cement, its poor compatibility, ease of forming crystal deposits and inability to respond to the historical value of the original buildings. Many early repairs have demonstrated these problems.However, Portland cement is still used in China as an effective reinforcement material for rocks that are in danger of falling and breaking.Unfortunately, there is little research on the use and the possible problems of such mortar as applied for conservation purposes. For this reason, in this paper, the workability, mechanical properties and durability of different types of Portland cement and Portland cement with different additives were studied. The results revealed that organo silicones could control the ion release without affecting the workability and strength of the mortar. The strength, resistance to ion release and waterproofing properties of super fine cement are better than for common cement, although its rate of SO2-₄ ion release is 2 to 5 times higher than that for common cement, because the super fine cement contains more CaSO₄ than common cement does. For practical applications, it is suggested using super fine cement with low CaSO₄ and adding organo silicone.

Abstract:The main parts of the Longmen Grottoes were hewn in carbonate rocks of the Zhangxia Formation (Zhangxia Fm),in which waterrock interaction is intense. Acid rain has further aggravated the problem of dissolution of carbonate rocks over the years. Carbonate rocks were grouped and sampled,in order to analyze their compositions and microstructures and to study their dissolution in an erosion experiment simulating acid rain.This experiment has be done in order to determine the laws controlling dissolution of the carbonate rocks of Zhangxia Fm. Results of the simulation experiment show that the rates of dissolution are different for each layer of Zhangxia Fm. The dissolving quality per unit area correlated positively to the Ca / Mg molar ratio in the carbonate rocks. The surface roughness of weathered oolitic limestone and ooides were closely related. Oolitic limestone is more resistant to chemical corrosion than ordinary limestone in the area studied. The conclusion of this research could serve as a kind of basic information for protection of the Longmen Grottoes.

Abstract:D reconstruction of ancient buildings has become an important aspect of the protection and restoration of historic sites. Threedimensional laser scanning data of the Great Wild Goose Pagoda was taken as an example in order to study in detail the process of obtaining and processing point cloud data for the 3D reconstruction of ancient buildings. The advantages of Cyclone, AutoCAD and 3DMax software to build a real horizontal, profile and vertical section model of the Great Wild Goose Pagoda were combined. The method of block modeling of massive point cloud data in Cyclone was briefly studied. This study showed that block modeling of spliced mass point cloud data for the Great Wild Goose Pagoda not only accelerated the speed of data processing, but also met accuracy requirements. The methods of target splicing and corresponding point joining together and the method of each stand splicing between the stations were combined, and then whole fitting adjustment to reduce the error was made. In the end, each station splicing error is no more than 3cm. In the process of modeling, the wall fitting is calculated, after adjustment of thousands of points, bringing the precision to 2mm.Finally, rendered and textured the model in the 3DMax software was combined, and a 3D model of the Great Wild Goose Pagoda was constructed. This work provides an important reference for the repair and digital archiving of the ancient architecture.

Abstract:Extensive amounts of corrosion products were found on all surfaces of a large ironpot unearthed from the Sizhou City site. By XRF analysis, iron metallographic analysis and Raman spectroscopy, it was found that the iron pot was made of gray cast iron, and that the main corrosion products were Fe₂O₃, Fe₃O₄ and γFeOOH. Due to unstable environmental conditions, the iron pot is still rusting. At the site, several measures are adapted to protect the iron pot, such as cleaning the corrosion, to brush phosphating liquid to stop rusting and to seal the surface by microcrystalline wax. The iron pot was in a stable condition after treatment, and there is no more corrosion. These field conservation measures provide a reference for the conservation of large unearthed archaeological relics

Abstract:The No.6 and 7 bulkheads and the keel of the No.8 bulkhead, as well as silt under the shipboard of an ancient ship found in the Banjing River were collected in order to desalt them for conservation purposes.The concentrations of major elements and ions were measured. The change of electrical conductivity during the desalting process was measured with an electrical conductivity meter. Results showed that concentration of major ions in the wood and silt was higher than that of control samples. The ions are mainly soluble salts. The degree of corrosion of the wood was positively correlated with content of ions inside:the higher content of the ions, the more corrosion . After desalting of the samples, electrical conductivity in the desalted solution was seen to decrease. Such testing results could provide certain guidance to future desalting of ancient ships.

Abstract:The Sichuan University Museum has a massive collection of ancient books and archives. The collection has long history and great value. Now, after longterm storage the books are suffering from different degrees of deterioration and need to be repaired and preserved utilizing scientific concepts. In this study, survey of the state of deterioration of these books has been carried out and the books has been analyzed by nondestructive or microdestructive methods, such as acidity measurement using a pH meter, optical microscopy, Fourier transform infrared spectrometry and scanning electron microscopy with energy dispersive Xray spectrometry. The results showed that these books suffered from different degrees of worm, mildew, moisture, pollution, fracture and embrittlement damage. The analysis revealed that these ancient papers are mainly pulped with bamboo and straw fibers. CaCO₃ can reduce acidification of the paper. The lack of alkaline substance such as CaCO₃ in the pulp, the growth of mildew on the surface and the addition of alum or iron during the production process all probably accelerate the acidification of papers.

Abstract:A piece of red brocade with a confronting bird design, preserved in Gansu Provincial Museum is incomplete, severely polluted and badly deteriorated. The brocade needed to be restored. Before restoration, nondestructive analysis using a color photometer, portable fluorescence spectrophotometer, digital camera and handheld portable microscope scalar were done. Objective and reliable data were collected on this piece of brocade in order to determine its weave structure and dye components, in order to provide scientific guidance for the subsequent protection and restoration. The fixed support method was adopted to stitch and reinforce the piece. The difficulties encountered during the restoration are analyzed. This piece of brocade looks solid in texture and coordinated in color after restoration.This conservation result can be a reference for similar restoration and research in the future.

Abstract:The use of “big data” is an inevitable consequence of museum digitization efforts. Starting with the Data Center project of the Shanghai Museum, this paper sets forth how Data Center reinforces the collection and storage of museum’s data as well as employs intelligent analytical methods based on the data to dig more deeply into valuable information with the purpose of playing an extensive role in the museum’s operation. Big data methods analyze the museum’s daily operation to form a useful data model and to lay a preliminary foundation for the digitization operation framework of the museum. This work also introduces the effective data mining tools and proposes future big data development strategies for museum use.