A variety of large decorated pottery towers were unearthed from the Daqu tombs in Beijing that provide valuable information about the tower architecture，social economy，science and technology of the Han dynasty. Research of these and similar items will continue to enrich our understanding of ancient ceramic materials and technology in the border regions of China during the Han and Wei dynasties. This research conducts an in-depth study of the techniques used to create Han dynasty pottery and has obtained valuable results pertaining tothe firing temperature，technology，and molding techniques applied. This research was conducted by analyzing

pottery fragments using Differential Scanning Calorimetry -Thermal Gravity Analysis（DSC-TG），Fourier Transform Infrared Spectroscopy（FT-IR），and Dilatometry（DIL）. The results reveal that there is a discernible discrepancy in the firing temperatures used to make pottery towers and flat saucers found in the same collection：the temperature used for the pottery towers was higher than that of the saucers，though both were fired in an oxidative atmosphere. As for the molding technology of the pottery towers，the key feature worthy of note is that the molds were made using interchangeable，combinable parts，which indicates that the production mode of the pottery towers in the Beijing area during the Han and Wei dynasties was already quite mature. These research results currently mark the latest information available for the study of ancient Chinese pottery tower production techniques.

The mural tombs of the Wei and Jin dynasties in Jiayuguan are often known as an “underground gallery” that contains inestimable artistic，historic and cultural value，and represents a major discovery in the history of human civilization. Portable X-ray fluorescence （XRF） spectrometry，Raman spectroscopy and digital microscopy were combined to perform a non-destructive analysis of the pigments used to paint the portrait bricks in the tombs，which are now collected in the Jiayuguan Great Wall Museum. Through observation of themicro-morphology of the surface of the paintings，together with a comprehensive analysis of the pigments and

chromogenic molecule Raman spectrum，this study has identified four types of pigments，including white，black，red and yellow. Chemical analysis of the pigments has shown that the white pigments are mainly composed of gypsum and calcite，the black is carbon black，the red is cinnabar and hematite，and the yellow is vanadinite， mimetite and wulfenite. In terms of research methodology，this study has also proven that the combination of X-ray fluorescence spectrometry （XRF） and Raman spectroscopy can accurately identify the mineral pigments in rock brick paintings，and that this techniquehas the advantages of being simple，fast，accurate and non-destructive. These results are meant to provide a scientific basis for the formulation of a plan for the restoration and protection of portrait bricks currently held in museum collections.

Determining the ideal cementing material is the key to repairing the flaking and deterioration of murals. Pure acrylic emulsion is a commonly used material for mural conservation. This study conducted an array of tests in order to analyze thethermal stability，structure，morphology and particle size of pure acrylic emulsion by usinglaser particle size analysis，thermogravimetric analysis（TG），X-ray diffraction （XRD），Fourier Transform infrared spectrum （FTIR），transmission electron microscopy （TEM） and scanning electron microscopy （SEM）. The relationship between the concentration of pure acrylic emulsion and its relative viscosity，

surface tension，pH and conductivity were investigated by viscometer，surface tensiontesting，pH meter and electrical conductivity，respectively. The stability of pure acrylic emulsion was analyzed by freezing and thawing tests，by being placed in room temperatureand heated environments，and centrifugation. In addition，diluted pure acrylic emulsion was applied to flaking and blistering on a simulated mural surface. The results show that pure acrylic emulsion has good thermal stability and film-forming properties that can form evenly distributed particles 150 nm in size. As the concentration of the material is increased，surface tension decreases and relative viscosity increases. Pure acrylic emulsion has good mechanical stability，freeze-thaw stability and salt tolerance. When flaking and blistered samples of simulated mural surfaceswere repaired with 2.5% pure acrylic emulsionand then passed through a total of 32 aging cycles，no significant difference was found in the repaired layer of paint following the weathering tests. This analysis indicates that pure acrylic emulsion is an excellent cementing materialfor the conservation of flaking，deteriorating or blistered murals.

Materials made of polyacrylate are some of the most commonly used polymer materials in mural conservation. At present，little research has been done to understand the molecular weight and distribution of these materials，which has a significant impact on both their physicochemical properties and functional applications. Advanced Polymer Chromatography（APC） is a technique for comprehensive molecular weight an-alysis with high resolution and fast analysis speeds that can calculate various statistics related to molecular weight and distribution in a single test. In this research，the molecular weight and distribution of five kinds of polyacrylate materials （ZB-SE-3A，ZB-SE-1，B72，AC33，and SF016） were measured using APC，with particular attention paid to molecular weight，composition and characteristic properties by focusing on the materials Primal AC33（discontinued） and its substitute Primal SF016. The results show that the average molecular wei-ghts of different polyacrylate materials are similar and can be ordered as follows from lowest to highest：ZB-SE-3A< ZB-SE-1<Paraloid B72< Primal AC33<Primal SF016. The molecular weight distributions of the materials fall into a medium width distribution， weight distribution width indexes （σn 2 ） are all 109 ，and Polydispersity In dexes（Mw / Mn） are between 1.5~2.7. The molecular weight multi-dispersion coefficients of AC33 and SF016 are similar，but SF016 has more branch structures to the effect that its average molecular weight across different properties is slightly greater than that of AC33. These two materials mainly differ in the ethyl and butyl in their branch chain structures. This study supplements the body of research on polyacrylate materials and provides theoretical support for the development and application of new materials that can be used in the conservation of murals; it is also meant to supplement the current practices used in the evaluation， screening，optimization and application of mural conservation materials currently in use.

Calcium oxalate film or coating is well known in the field of cultural conservation as an effective method of protecting carbonate stone relics because of its low solubility，good compatibility with carbonate surfaces and good reversibility. Because of non-uniformity in the substrates，the uncontrollability of the reaction process and the amount of products that are involved when using a chemical solution method to make protective coatings on carbonate rocks，calcium oxalate coatings produced by this method are often defective and fail to protect the surfaces they cover. There are two main ways to improve the properties of these coatings: the calcium oxalate crystal structure can be modified with acidic solvents to improve coating densification，or；the area covered by the film can be increased by using slowly hydrolyzed oxalate solutions. This study sequentially applied ammonium oxalate solution，dimethyl oxalate mixed solution，and calcium acetate mixed solution to a marble substrate and then tested the surface with XRD，SEM，and stain resistance tests. The results demonstrate that the calcium oxalate coating made using these methods is denser and more effective at resisting dirt and scuffing.Moreover，the calcium oxalate coating can be easily removed with little effect on the object’s appearance.

Influenced by natural factors such as light，rainfall，environmental temperature and humidity changes，water and salt migration and man-made damage，most of the historic buildings have been damaged to certain extent. Due to the complexity of material composition and disease types of historic buildings，the development of effective restoration materials has always been an important and difficult problem to be solved by conservator. Natural hydraulic lime has moderate mechanical strength， good flexibility，workability and waterproof performance，and can be well compatible with the reinforced materials. Compared with cement and traditional air hardening lime，natural hydraulic lime has irreplaceable advantages in the restoration of historic buildings. However，the setting speed，early strength and durability of natural hydraulic lime restoration mortar need to be improved，which affects the restoration effect to a certain extent. In recent years，the research work on the modification of natural hydraulic lime mainly focuses on exploring the effects of mix proportion，additives and curing conditions on the pore structure，mechanical properties and durability of mortar，but the research is not comprehensive and sufficient. In addition，relevant scholars have carried out the manufacture of hydraulic lime，but the research on the service performance and durability of the prepared hydraulic lime is not sufficient. At present，we still mainly rely on imported products to carry out the restoration of cultural relics，with high cost. Therefore，there is great research space and significance in improving the service performance，prolonging the service life and saving the cost of natural hydraulic lime utilization. This paper introduces the research progress of natural hydraulic lime based mortar in theory，engineering application， modification and preparation，expounds the problems that can be improved in practical application，and puts forward some suggestions for the further research of natural hydraulic lime based mortar.

Reinforcement earth ruins by chemical materials is one of the more effective means to protect the artifacts of earth ruins. Acrylic non-aqueous dispersion has the advantages of good reinforcement strength and good infiltration performance. It has been used in the actual protection work， but there are still some problems. In the present experiment，the raw material and preparation process of Acrylic non-aqueous dispersion were firstly enhanced to improve the material preparation efficiency and material penetration properties. Secondly，to explore the influence of different factors on the permeability of the material，so that the best results can be

achieved by choosing the right material for different situations in practical applications. Finally，the reinforcement mechanism of the material was investigated，and it was found that the acrylic non -aqueous dispersion mainly formed a film and then acted as a bond to reinforce the soil，providing a basis for the subsequent removal of the material.