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Abstract Damage and fracture of archaeological potteries not only jeopardize the long-term preservation but also hinder their exhibition. To repair these pottery sherds effectively, this study introduces a novel inorganic phosphate-based adhesive and evaluates its effectiveness through a series of experiments. To determine the optimal base adhesive, the paper investigates the influence of varying weight ratios of the H2O–H3PO4 system and the Al(OH)3–H3PO4 system on properties including tensile lap-shear strength, microstructure, high-temperature resistance and phase composition. However, the original black color of the traditional CuO–phosphate adhesive limits its application. The innovation of this study lies in the addition of nano-TiO2 to the adhesive, which not only improves the bonding strength but also adjusts the color of the adhesive. This study has defined the optimal formulation (i.e., base adhesive = m[Al(OH)3]:m[H3PO4] = 7:100, filler = 10wt% nano-TiO2), and the final product shows no residual acid in adhesives. Additionally, the fracture surfaces are successfully bonded with a high strength of 3.56 MPa. Various ageing tests including dry-thermal ageing, hygrothermal ageing and UV irradiation ageing are conducted to assess the ageing resistance of the inorganic phosphate-based adhesive. The results indicate strong tolerance of adhesive to high temperature and high humidity environment. Preliminary applications in archaeological pottery restoration suggest that the inorganic phosphate-based adhesive offers considerable promise for repairing shattered pottery. Graphical Abstract

Abstract Cement-based grouting material is widely used to reinforce the unsafe rock and control seepage of rock-carved relics although it is considered inappropriate in protection of ancient sites. As this approach is irreversible, a longer service life is desirable for the grouting material and methods to predict the service life are needed. Here we propose a universal formula based on the dissolved amount of calcium ion to predict the deterioration rate of cement-based grout caused by acid deposition in the laboratory. The experimental results showed that the dissolved amount of calcium ion had a linear relationship with lnT and the pH value, with better accuracy when the pH value was greater than 3.0. This work maybe could provide a facile and quantitative method to help us predict the service life of cement-based grouting material under acid rain attack outdoors.

Since their invention by Akachi in 1990s, pulsating heat pipes (PHPs) have attracted widespread interest and application in practice, e.g., grinding, chip cooling, the thermal management of batteries, etc., owing to their notable efficiency in heat transfer and their simplicity and flexibility in structure. Key factors influencing the heat transfer efficacy of pulsating heat pipes are mainly attributed to the thermophysical properties of the working fluid, the structural parameters, and the operating conditions. Research on pulsating heat pipes is conducted through theoretical investigations, numerical simulations, and visual experiments. In this paper, the research on PHPs in recent decades is reviewed with the consideration of the heat transfer performance mechanism and application of pulsating heat pipes, especially research under operation conditions such as with “status with motion” and with “inconsistent heat flux”.

In this work, the performance and mechanism of a Chinese traditional sucrose-modified rammed earth-lime were discussed in lab for its potential utilization in the restoration of rammed earth-lime architectural heritages. The results showed that the addition of sucrose would effectively improve compressive strength and wet-dry resistance of rammed earth-lime. The addition of sucrose would markedly increase the concentration of Ca2+ in pore solution and prolong the duration of high temperature, thereby making the microstructures of the rammed earth-lime much more compact and improve the formation of C-S-H gel. These may be the reasons for the better performance of sucrose-modified rammed earth-lime. In general, the optimal amount of added sucrose was about 1–3 % by weight of the total mortar.

Abstract There are still many difficulties in the recovery and long-term preservation of underwater archaeological artifacts, in situ preservation should be the first choice before further procedures are considered. However, the materials, preservation status, and preservation environment of underwater artifacts are diverse, resulting in many fragile artifacts facing difficult situations. In order to prevent serious damage, it is a safe protective strategy to preserve them in a controlled environment for a long time after excavation. Extraction and transfer of fragile cultural relics are vital parts of this strategy. Due to the complexity of the underwater environment and the vulnerability of fragile artifacts, safety in extraction and transfer still faces enormous challenges. Researchers have developed new materials and technologies to tackle this problem. This paper focuses on introducing and developing prospects to different preservation techniques for fragile artifacts from underwater sites.

Abstract Background Carnitine palmitoyl transferase 1A (CPT1A), the key regulator of fatty acid oxidation, contributes to tumor metastasis and therapeutic resistance. We aimed to identify its clinical significance as a biomarker for the diagnosis and prediction of breast cancer. Methods Western blot, ELISA and in silico analysis were used to confirm CPT1A levels in breast cancer cell lines, cell culture medium and breast cancer tissues. Four hundred thirty breast cancer patients, 200 patients with benign breast disease, and 400 healthy controls were enrolled and randomly divided into a training set and a test set with a 7:3 ratio. Training set was used to build diagnostic models and 10-fold cross validation was used to demonstrate the performance of the models. Then test set was aimed to validate the effectiveness of the diagnostic models. ELISA was conducted to detect individual serum CPT1A levels. Receiver operating characteristic (ROC) curves were generated, and binary logistic regression analyses were performed to evaluate the effectiveness of CPT1A as a biomarker in breast cancer diagnosis. CPT1A levels between post-operative and pre-operative samples were also compared. Results CPT1A was overexpressed in breast cancer tissues, cell lines and cell culture medium. Serum CPT1A levels were higher in breast cancer patients than in controls and were significantly associated with metastasis, TNM stage, histological grading and molecular subtype. CPT1A levels were decreased in post-operative samples compared with paired pre-operative samples. Moreover, CPT1A exhibited a higher efficacy in differentiating breast cancer patients from healthy controls (training set: area under the curve, AUC, 0.892, 95% CI, 0.872–0.920; test set, AUC, 0.904, 95% CI, 0.869–0.939) than did CA15–3, CEA, or CA125. Conclusion CPT1A is overexpressed in breast cancer and can be secreted out of breast cancer cell. Serum CPT1A is positively associated with breast cancer progression and could serve as an indicator for disease monitoring. Serum CPT1A displayed a remarkably high diagnostic efficiency for breast cancer and could be a novel biomarker for the diagnosis of breast cancer.

Brown sugar and sticky rice were frequently used as organic additives in Chinese mortars. This study applied enzymatic spectrophotometric methods to identify sucrose and starch contents in traditional Chinese lime- and earth-based mortars. The focus was to understand and evaluate the qualitative detection capacity of enzymatic method in mortars, by first applying the method on a series of lab-prepared mortar specimens with specific amounts of brown sugar and sticky rice addition, then on historic mortar samples suspected to contain brown sugar and sticky rice. The potential contribution and limitations of enzymatic method in analysis of sucrose and starch in mortars was compared with other common available analytical methods. The results suggested that for lab-prepared brown sugar mortar specimens, enzymatic method was more sensitive and exclusive than chemical method, and particularly had higher detection capacity in lime mortars. For simulated mortars with sticky rice addition, enzymatic method showed no distinct detection capacity differences among the studied inorganic binders and comparing with chemical methods was more sensitive in earth-based mortars. Enzymatic analysis on historic mortar samples was able to distinguish some false-positive results from the chemical and FTIR analysis, which was then corroborated by SEM.

Abstract Water seepage is the primary cause of stone carvings corrosion in karst caverns, which is typically treated with cement-based grout intervention. In this paper, long-term monitoring (more than 1 1/2 years) was carried out in Qinglin cave and Yanxia cave in Hangzhou, China, to quantitatively evaluate the advantages and disadvantages of ordinary Portland cement- and superfine cement-based grout intervention. Results showed that both materials were efficient in preventing water seepage, reducing it by half after the grout interventions. Grout intervention had obvious efficacy in blocking off the strong water seepage points, at the same time decreasing seepage differences among seepage points. Ion Chromatography results suggested that the concentrations of Ca2+, Cl− and SO4 2− in the seeped water in both caves increased after intervention, and the concentration of SO4 2− in the seeped water after superfine cement application in Qinglin cave was much more than that in the seeped water in Yanxia cave, where ordinary Portland cement was applied. Therefore, using superfine cement may bring more potential risks than ordinary Portland cement. However, X-ray diffraction (XRD) and conductivity analysis results presented that these ions seemly did not deposit on rock surfaces of the caves during the monitoring period.

An amendment to this paper has been published and can be accessed via the original article.