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This paper focuses on the characterization of materials from fragmented pieces of an imperial lacquer plate in the Luozhuang Han tomb, which dates to the early Western Han dynasty. Various non-invasive and minimally invasive techniques were performed, including optical and electron microscopy, XRF, Raman spectromicroscopy, FT-IR, XRD and THM-Py-GC/MS. The lacquerware pieces consist of a five-layer structure, which includes (from the top): a red pigmented layer, two lacquer finish layers, a ground layer and a canvas/wood foundation layer. The red layer consists of ground cinnabar mixed with urushi. The lacquer finish layers are made of urushi mixed with perilla or tallow tree oil, without any pigment. The ground layer is a mixture of organic materials including urushi, tree oil and amorphous carbon (possibly burned ashes) and inorganic fillers such as quartz, albite and potassium feldspar. Urushi was also identified in the canvas/wood foundation layer. Though highly degraded, the canvas is probably made of hemp (bast fibres). The identification of high concentration of drying oil indicates an intentional addition of oil into the urushi to retard the rate of hardening and to increase gloss. [ABSTRACT FROM AUTHOR]

Abstract: Four different mesoporous silica (MS) samples were synthesized for assessment as candidate rapid-response desiccant materials. Their behaviour was compared with that of conventional desiccants. The aim was to enable tuning of hygrothermal functional behaviour by correlating this with microstructural composition. Pore geometry was characterized and validated using small-angle X-ray diffraction, Brunauer–Emmett–Teller analysis, Barrett–Joyner–Halenda analysis and high-resolution transmission electron microscopy. The volume and mean diameter of the mesopore network are directly related, and when increased cause a proportional decrease in macropore volume and bulk porosity, suggesting that the pore wall thickness decreases at larger mesopore volumes. Thermophysical properties were characterized using modified transient plane source and differential scanning calorimetry. Vapour storage and sorption/desorption response rates were characterized using modified dynamic vapour sorption (DVS) techniques. The DVS response time, t emc, has a positive logarithmic relationship with both mesopore diameter and mesopore volume, whilst vapour permeance appears to be inversely related. All MS samples had a significantly higher vapour storage capacity and quicker DVS response rate than the conventional desiccants, including silica gel, zeolite, molecular sieve and bentonite. [Copyright &y& Elsevier]

Abstract: Amphiboles are the main mafic minerals in most metaluminous to peralkaline alkali-feldspar granites and syenites, and they usually preserve an important record of the compositional evolution of the melts from which they crystallize. In the alkaline association of the Serra da Graciosa A-type Granites and Syenites (southern Brazil), amphibole compositions span a large range, including calcic, sodic–calcic, and sodic amphiboles. Calcic amphiboles are typically observed in the metaluminous rocks, while sodic amphiboles are characteristic of the more strongly peralkaline rocks; sodic–calcic amphiboles are found in intermediate varieties. Compositional variations record the differentiation trends within two petrographic series of the alkaline association. The overall evolution of amphibole compositions is similar in both: they reveal a progressive increase in Na and Fe3+ with differentiation (increase in alkalinity of the magmas), a characteristic shared by undersaturated peralkaline (or agpaitic) differentiation trends. In detail, however, the evolutions of the amphibole compositions in the two series are distinct. In Alkaline series 1, the cores of the crystals form a continuum from calcic to sodic compositions, with the exception of a small compositional gap within the sodic–calcic amphiboles. The rims, however, show compositions that diverge from this main trend; this divergence results from increasing amounts of the oxy-amphibole component, and reflects more oxidizing conditions at the final stages of magmatic crystallization. In Alkaline series 2, these oxidation trends are much more subtle and a reverse trend is observed in the sodic amphiboles. Sodic–calcic amphiboles are in several cases replaced by intergrowths of post-magmatic sodic amphibole and Al-poor (“tetrasilicic”) biotite. [Copyright &y& Elsevier]