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Building multiple chemical crosslinks is an effective strategy to improve mechanical properties and to diversify final application of polysaccharide nanoparticles reinforced poly(vinyl alcohol) (PVA) physical hydrogels. In this work, PVA/cellulose nanofibers (CNFs) were used as composite substrate to fabricate ionic conductive hydrogels for strain sensor. Three types of characteristic crosslinks, including chemical crosslinking via boronic ester covalent bonds only, and with additional metal coordination bonding, as well as coexistence of physical crosslinks via PVA crystallites and aforementioned two kinds of chemical crosslinks, were constructed. The sample with triple crosslinks has superior mechanical strength and resistance to fatigue, and the polydopamine/Fe

Natural hydraulic lime (NHL) based grout has been widely used in construction project related to ancient architecture in recent decades. In order to improve grouting performance of NHL based grout, silica fume (SF) and silicon-acrylic latex (SAL) were incorporated in the preparation of grout. For the grout in fresh state, compared with control grout, bleeding rate of modified grout with SF and SAL incorporation decreased. Wettability, interfacial bond and simulated grouting properties of grout were improved. For the grout in hardened state, water absorption of grout decreased. Compactness, mechanical strength and salt resistance were improved. SAL played a more important role in improving both grout’s flexural strength and interfacial bond property between grout and consolidated matrix. Generally, combined use of SF and SAL made the grout with the most beneficial grouting performance.

Natural hydraulic lime (NHL)-based mortars were prepared by introducing isobutyltriethoxysilane (SO) and silica fume (SF) as partial replacement of NHL by percentage of 20%. Main physical, mechanical and durability properties of mortars were evaluated. Compared with control mortars, apparent density, water absorption and shrinkage of modified mortars decreased, mechanical and durability properties were improved. Generally, SF was more effective than SO in improving main physical and mechanical properties of mortars. The reason was attributed to pozzolanic reaction between SF and Ca(OH)2, which generated more hydrate product and refined pore structure. SF modified mortars showed the highest compressive strength (CS). The combined use of SF and SO showed the largest improvement in mortars’ flexural strength (FS) and bond strength (BS), for that SO played a bridge coupling role between components in mortars. Durability properties of mortars were greatly improved by the presence of SO and it was related to water repellency of SO. Mortars prepared with SF and SO had the highest durability.

To definitively diagnose active pulmonary Tuberculosis (TB), Mycobacterium tuberculosis complex (MTBC) bacilli must be identified within clinical specimens from patients. In this study, we introduced a rapid and visual detection method of MTBC using recombinase polymerase amplification (RPA) combined with lateral flow (LF) strips. The LF-RPA assay, read results with naked eyes, could detect as few as 5 genome copies of M. tuberculosis H37Rv (ATCC 27294) per reaction and had no cross-reactions with other control bacteria even using excessive amount of template DNA. The system could work well at a broad range of temperature 25–45 °C and reach detectable level even within 5 min. When testing a total of 137 clinical specimens, the sensitivity and specificity of the LF-RPA assay were 100% (95% CI: 95.94%–100%) and 97.92% (95% CI: 88.93%–99.95%), respectively, compared to culture identification method. Therefore, the LF-RPA system we have demonstrated is a rapid, simple, robust method for MTBC detection which, subject to the availability of a suitable sample extraction method, has the potentiality to diagnose TB at the point-of-care testing.

Compared with other wall paintings, tomb murals are rarely and have been most seriously damaged by natural weathering, erosion of bacteria and vandalism. Traditional identification methods are time-consuming, laborious, and confined to the visible light range, which mainly relies on expert's experience, analogy and visual color. This calls for new recording methods for mural site protection, relics restoration and repairs. Hyperspectral imaging can capture pictures of spectral range from visible to near infrared light, which render visual enhancement of faded tomb murals. This paper presents a method that can extract faded mural pattern from the hyperspectral images of mural, taking the leaf-like mural patterns in typical Tang dynasty tomb in China as an example. In the method, the faded leaf-like patterns are highlighted through normalization of sensitive spectral bands and extracted by density slice and masking on image space. The result shows that the method can extract the target pattern efficiently with the simple operations.

Honglvcai (also named red and green porcelain) was prosperous in Jin Dynasty (1115–1234 AD) and had played a pivotal role in ancient ceramic development history in China, connecting with former glazed pottery Tang Sancai and later polychrome porcelain like Wucai and Doucai, but little scientific analysis has been reported up until the present day. In this research, one precious sherd unearthed from Linshui (one major site of Cizhou kiln system) in Hebei province was adopted as specimen for compositional and micro-structural analysis. Optical microscope (OM), X-ray fluorescence spectrometry (XRF) and energy dispersive spectrometry (EDS) in association with scanning electron microscope (SEM) were employed for investigation of the multi-colour decors and black outline. The extensive data reveal that although high lead content has been detected by surface analysis and the iron-rich pigment particles do locate in the middle of the whole vitrified region, the black outline in fact belongs to high temperature fired under-glaze painted decoration, rather than the deceptive low temperature fired lead based over-glaze decor or the generally believed ‘sandwich’ (glazed twice) structure. Furthermore, a corresponding criterion then has been established for differentiation among three main decorating methods, especially for the puzzling ‘sandwich’ effect scenario. Moreover, once this ongoing vexed debate over the nature of the black decoration in Cizhou kiln system has been clarified, it is then reasonable to deduce that, from idealistic and technical point of view, there is no difference between producing prototype like this sherd and real Doucai in Ming dynasty (1365–1644 AD) except for the types of under-glaze pigment. Overall, all these results together firstly provide realising scientific proofs for the origin of Doucai.

Research on the sedimentary architecture and provenance of sublacustrine fans is crucial not only to better understand the gravity flow evolution in lacustrine basins but to successfully locate hydrocarbon reservoirs. This study targets at a sublacustrine fan with a large petroleum reserve that has been revealed by drilling within an Eocene lacustrine succession in the Fushan Depression, northern South China Sea. The sedimentary architecture of the sublacustrine fan was investigated through the integration of core, well logs and 3D seismic data, and its provenance was identified by detrital zircon U Pb dating. The examination of 117 m long continuous drilling core reveals four major lithofacies in the sublacustrine fan deposits, which are interpreted as deposits of two types of gravity flows (cohesive debris flows and turbidity currents). The cohesive debris flows developed in the lower section are mainly composed of massive gravelly mudstones with various floating clasts and high clay content, whereas the turbidity currents in the upper section are characterized by parallel to ripple bedding and normal graded bedding. These observations reflect a transformation from cohesive debrites to turbidites from deep to shallow water environments. In addition, provenance analysis of 648 detrital zircon U Pb ages yield a well-defined relationship between potential provenance areas and sublacustrine fan deposits in the deep lake. The U Pb age pattern of the fan is similar to that of northern fan delta deposits, but different from sediments from the western and southern deltas, suggesting that the sublacustrine fan was sourced from the north. Therefore, a deep-lacustrine depositional model is proposed for the sublacustrine fan, showing a gravity-driven evolution process from fan delta front in the northern slope into cohesive debrites and then turbidites in the lake center. This was mainly controlled by fault-related topography and sediment supply. This study highlights the effective use of the detrital zircon U Pb dating method to identify the provenance direction of sublacustrine fans, and the proposed depositional model may be applicable to reservoir prediction in other lacustrine basins.

The Fushan sag is an important petroleum-bearing unit in the Beibuwan Basin, South China Sea. However, genetic relationship between oil and source rocks has not been well understood. In this work, 43 mudstone samples and 22 crude oil samples in the sag were collected for molecular geochemical and isotopic analyses to investigate this relationship. The geochemical data shows that the mudstones in Liushagang formation have poor to good oil generation potential with TOC ranging from 0.45 to 2.19 wt% and the kerogen is mainly type Ⅱ. Two types of crude oils were identified in this study. The first type of Group A oils including the subgroup A1 and subgroup A2 has the characteristics of low maturity with low saturated hydrocarbon content and lighter δ13C values in the Huachang uplift. The source rocks for the Group A oils were deposited under suboxic to oxic and freshwater environment containing more terrestrial higher plant and less angiosperm. The subgroup A1 oils in Els11 reservoirs are separated from subgroup A2 in the Els12 reservoirs by relatively lower maturity. The subgroup A1 and subgroup A2 oils are closely related to the Els1 to Els21 and Els12 to Els21 source rocks, respectively. While the second type of oils including Group B and Group C oils has higher level of maturity with higher saturated hydrocarbon content and heavier δ13C values. The source rocks of Group B oils were deposited in a freshwater environment with lower salinity, and more angiosperms and terrestrial higher plants input than those of Group C oils. Two subgroups are divided in the Group B oils, of which subgroup B1 oils have higher maturity and their source rocks were deposited in lower salinity with more terrestrial higher plant input than that of subgroup B2 oils. The subgroup B1 oils occurring in the Els31 reservoirs from the Huachang uplift are likely related to Els31 source rocks, while subgroup B2 oils in the Els22 reservoirs from the southern slope area of the Bailian subsag is linked with mixed source of Els22 and Els31 mudstones. The Group C oils are distributed in Els22 and Els31 reservoirs in the Huachang uplift and their oil source are from Els32 mudstones. Two petroleum plays are likely divided by the mfs in Els2 based on the oil-source correlation in the sag. Group B and Group C oils belong to the lower play, and Group A oils only occur in the upper play. The distribution and accumulation of different groups of oils are mainly controlled by the special two-layered tectonostratigraphic framework and the transport ability of fault zone in the sag. This study clarifies the types of oils, as well as the oil-source correlation and the spatial distribution of different groups of oils. The results could benefit the further petroleum exploration and resource evaluation in the sag.

Research on corrosion of archaeological porcelain glaze has rarely been carried out in the past, although corrosion damage precious heritage items continuously. A group of black-glazed porcelains from the Song Dynasty was excavated at a poor conservation site in Chongqing, and one of their fragments was investigated with optical microscope, SEM-EDX, FTIR and Raman spectroscopy. The results showed that the alteration crust of the glaze mainly consisted of silica-rich gel and contained a variety of heterogeneous phases, including the liquid phase separation structure and different crystals. The crystals mainly include hematite, magnetite, rutile, pseudobrookite and silicon dioxide. The inter-diffusion reaction between alkalis in glaze and hydrogenated species in contact solution was the main reaction, which led to the formation of silicon-rich hydrate layers. The amorphous layers eventually transformed into acicular silica crystals under long exposure to environment.

This paper presents the results of the analysis investigation of the lamp oil remains from a Tang Dynasty tomb (901 AD) in Lin An County, Zhejiang Province of China. The techniques applied include direct pyrolysis gas chromatography and mass spectrometry (Py-GC/MS), Py-GC/MS with in-situ hydrolysis and methylation, as well as Py-GC/MS with double-shot method. Through the analysis, plant oil—most likely perilla oil was identified in the sample. The detection of the aromatic compounds (such as calamene, calamenene, cycloisolongifolene, 8,9-dehydro-neoisolongifolene, cadalene, cedrene, ylangene, cuparene and cedrol) indicates the presence of cedar oil and other essential oils in the lamp remains. Unexpectedly, the marker compounds of urushi including methyl 7-(2,3-dimethoxyphenyl) heptanoate, methyl 9-(2,3-dimethoxyphenyl) nonanoate and 1,2-dimethoxy-3-pentadecylbenzene were also detected in the sample.

The effect of three kinds of lead additives on Chinese Purple synthesis was studied in this research. The barium source of the Chinese Purple was barium carbonate (BaCO3), and three common lead additives in the ancient samples, lead oxide (PbO), lead sulfide (PbS) and lead carbonate (PbCO3), were used in this study. The microstructures of the three additives were observed by SEM, and the thermal analyses of three formulation powders were conducted by TG. After the reaction, compositions and chrominance of the pigments were measured by XRD and colorimeter, respectively. It is shown that PbCO3 could decrease the synthesis reaction temperature effectively, thus the pigment synthesis reaction could occur under the low temperature (720 °C–900 °C), and a brighter, purer Chinese Purple pigment could be obtained.

In order to increase energy and resources utilization efficiency, and to find hydraulic mortars with improved properties, in this paper we employed diatomite as partial replacement of natural hydraulic lime NHL2 (NHL) and masonry waste powder (MWP) as aggregate in the preparation of mortars. Diatomite was used at 0%, 10% and 20% replacement by weight for NHL2 and the mortars were designed with different water binder ratios (w/b). The physical, mechanical, and anti-aggressive properties such as freeze and thaw, and acid and sulfate resistance properties of mortars were tested after 14, 28 and 90 days of curing. The introduction of diatomite reduced the density of mortars, and it also reduced the total amount of raw materials, especially the amount of NHL, to prepare same volume of mortars. Diatomite replacement generally enhanced the compressive and flexural strength of hydraulic mortars. The enhancement mainly happened after 14 days of curing when pozzolanic effect was noticeable. Diatomite replacement percentage and w/b influenced porosity, compactness and strength of mortars. There existed optimal diatomite replacement percentage and w/b for mortars to attain largest strength. The introduction of diatomite improved acid and sulfate resistance of mortars greatly. All the hydraulic mortars studied in this paper can still well develop strength under freeze and thaw condition.

Ancient Chinese objects dating from the Warring States period (475–221BC) to the Han dynasty (206BC–220AD), including faience beads, wall paintings, polychrome decoration on pottery, stone and bronze objects, were studied using Raman microscopy and polarized light microscopy (PLM). Chinese Blue (BaCuSi 4 O 10 ) and Chinese Purple (BaCuSi 2 O 6 ) were identified, and additionally dark blue particles of a new pigment BaCu 2 Si 2 O 7 were also detected in purple decoration. Based on PLM observation, Chinese Blue, Chinese Purple and BaCu 2 Si 2 O 7 frequently coexist in single polychrome samples and cannot be individually identified using other analytical methods because of the minute amount that these chemicals present: sometimes comprising just one or two particles. The use of Raman spectroscopy can identify such small presences. This paper illustrates the man-made barium copper silicate pigments along the Qin historical development and shows the advantage of PLM combined with Raman spectroscopy to analyses pigments giving us an overall picture of the dates and the places where barium copper silicate pigments were used in ancient China. Their origin, decline and manufacturing techniques are also discussed.

Drilling has shown that there is a large petroleum reserve in the Liushagang Formation of the Fushan Depression, South China Sea from reservoirs of the sublacustrine fans. To reduce the risk associated with exploration, the sedimentary characteristics of the sublacustrine fans should be identified and described. Analysis of the drilling cores, well data and 3D seismic data was conducted to identify and interpret the sublacustrine fans which formed in a lacustrine succession as the low-stand fan of the 2nd member of Liushagang Formation (SQEls2). The reservoirs were commonly associated with pebbly conglomerates, mudstone shivers, muddy debris, various deformation structures including micro-faults, liquified deformation structure, ball and pillow structure, slump and stress-release deformation. Further contrastive analysis of sedimentary characteristics and palaeogeomorphology between the western and eastern sublacustrine fans indicates that they belong to two different types of sublacustrine system in continental basins. More specifically, the western fan, controlled by the multi-level step-fault belt, is a typical gravel-rich sublacustrine system which is characterised by structurally controlled, high gradient (2.8–3.3°), admixtures of muddy debris and pebbly conglomerates and poor reservoir quality, while the eastern fan, controlled by the flexure slope-break belt, is a sand-rich sublacustrine system dominated by relatively low gradient (2.0–2.5°), general fining-upwards trend with good reservoir quality. Therefore, the development of future exploration should be conducted at different levels in the Fushan Depression.

Prototype foamy virus encodes a transactivator called Bel1 that enhances viral gene transcription and is essential for PFV replication. Nuclear localization of Bel1 has been reported to rely on two proximal basic motifs R(199)H(200) and R(221)R(222)R(223) that likely function together as a bipartite nuclear localization signal. In this study, we report that mutating R(221)R(222)R(223), but not R(199)H(200), relocates Bel1 from the nucleus to the cytoplasm, suggesting an essential role for R(221)R(222)R(223) in the nuclear localization of Bel1. Although not affecting the nuclear localization of Bel1, mutating R(199)H(200) disables Bel1 from transactivating PFV promoters. Results of EMSA reveal that the R(199)H(200) residues are vital for the binding of Bel1 to viral promoter DNA. Moreover, mutating R(199)H(200) in Bel1 impairs PFV replication to a much greater extent than mutating R(221)R(222)R(223). Collectively, our findings suggest that R(199)H(200) directly participate in Bel1 binding to viral promoter DNA and are indispensible for Bel1 transactivation activity.

A royal tomb of early period of the Western Han dynasty (206 B.C–8 A.D) was excavated by archaeologists in Qingzhou County, Shandong Province in 2006. Over 2000 polychromy terracotta soldiers, horses, chariots, servants etc. were unearthed from the tomb. All the terracotta figures are one quarter or one sixth as large as the livings, most of them were painted with well designed patterns. In order to gain complete information about the materials and techniques used for the polychromy on the terracotta army, five samples from the painted areas were taken. In addition, one sample from the area to adhere one leg to the ploychromy horse body was also obtained. The analytical techniques applied include XRF, FTIR, Py-GC/MS and GC/MS. Chinese purple, cinnabar, lead red and ochre were used as pigments, while animal glue was identified as binding medium and adhesive in the polychromy terracotta army in the Han Dynasty. The results definitely will provide new evidence about the materials and technologies used in Han Dynasty. Especially, the binding medium identified is different in comparison with Qin Shihuang's terracotta army (259–210 BC).

Unusual short chain lanostanes (C 24 and C 25 ) and C 30 lanostane were identified in sulfur rich crude oils from the Jinxian Sag, Bohai Bay Basin, northern China. Besides the regular steranes (C 27–30 ), a series of 4-methyl steranes (C 22−23 , C 27−30 ), 4,4-dimethyl steranes (C 22−24 , C 28−30 ), short chain steranes (C 23−26 ), abundant pregnanes (C 21−22 ) and androstanes (C 19−20 ), together with sulfur containing steroids (20-thienylpregnanes and thienylandrostanes) were detected in the aliphatic and branched-cyclic hydrocarbon fraction of these crude oils. A literature survey of some long chain sterane analogues (e.g., A-nor-steranes, norcholestanes, C 30 steranes, lanostanes) and pregnanes seems to point to a sponge and/or dinoflagellate source. 4-Methyl, 4,4-dimethyl steroids and lanosterols (4,4,14-trimethyl steroids as the basic skeleton of lanostanes) can be derived from methanotrophic bacteria. Thus, a biological origin from a prokaryotic methylotroph can be used to explain the common source of abundant short chain steranes (C 23–26 ), 4-methyl (C 22–23 ) and 4,4-dimethyl steranes (C 22–24 ), as well as lanostanes (C 24–25 and C 30 analogues) in our oil samples. Generally, the steroids appear to have been extensively sulfurized with sulfur substitution at the C-22 position in the side chain during the early stage of diagenesis, which was readily subject to attack by bacterial degradation (enzymatic cleavage) and/or abiotic oxidation. As a consequence, short chain sterane analogues (e.g., abundant pregnanes and androstanes in this study) and short chain lanostanes (C 24 −C 25 ) might later be released through cleavage of weak C–S bonds at the C-22 carbon in the sulfurized steroids and lanostane sulfides. Finally, the formation of the short chain C 24 −C 25 lanostanes and distinctive occurrence of short chain steranes in this study can be well explained by microbial biodegradation of sulfurized lanostanoids and steroids in the reservoir.

The aim of this work was to assess the ability of four representative fractions (saturated, aromatic, polar and asphaltene) of crude oils to participate in thermochemical sulfate reduction (TSR) and thus to evaluate their pyrolysis behaviors, which is of great relevance to the stability of reservoir hydrocarbons. Experiments simulating reactions between oil fractions and magnesium sulfates (anhydrous MgSO4 and hydrated MgSO4·7H2O) at a constant temperature of 420 °C and under a pressure of 50 MPa were conducted over a period of 24 h using a gold tube confined system. The yields of non-hydrocarbon and hydrocarbon gases and their δ13C values were measured and compared in order to reveal the main control factors on TSR under practical geological conditions. In pure blank pyrolysis experiments with oil fractions cracking without TSR, different pyrolysis rates were seen for the four petroleum fractions with a sequence of saturated > asphaltene > polar ≫ aromatic. Minimal yields of C1–C5 hydrocarbons in the aromatic fraction can mainly be attributed to the greater thermal stability of aromatic compounds, which was also reflected by their positive δ13C signatures. Upon addition of anhydrous MgSO4 to the saturated fraction, a small quantity of H2S was generated, indicating that only a weak TSR occurred in this series. Upon addition of hydrated MgSO4·7H2O to the four petroleum fractions, high yields of H2S were generated, indicating that water plays an important role in the occurrence of TSR. The presence of nitrogen and/or oxygen containing heteroatomic compounds in the polar fraction decreases the yields of H2S when subjected to MgSO4 TSR. Similar yields of H2S from the saturated, aromatic and asphaltene fractions revealed that TSR occurring in the aromatic fractions is unlikely to be associated with the opening of benzene rings but closely related to availability of hydrogen atom in the alkyl moiety. The addition of MgSO4·7H2O, TSR can significantly enhance the yield of methane, also reflected in an increase in its δ13C value. Besides methane, the other gaseous hydrocarbons (C2, C3) in the MgSO4·7H2O series also showed some less negative δ13C values relative to the blank series, irrespective of the fraction type. Relative to the other fractions (saturated, polar and asphaltene), low yields of C1–C5 gaseous hydrocarbons derived from the aromatic fraction could be attributed to the greater stability of the benzene ring and indicate that paraffinic oils may be more susceptible to thermal or thermochemical alterations than aromatic oils under the conditions of real subsurface reservoirs.

Relatively abundant C30 17α(H)-diahopane has been detected in oils and rock extracts in the Fushan Depression, a Tertiary lacustrine basin of the Northern South China Sea. C30 17α(H)-diahopane/(C30 17α(H)-diahopane + C30 17α(H)-hopane) ratios (DI) increase with increased burial depth of the source rocks. DI values of most oils from the upper unit ( E 2 l 3 1 ) of the third member of the Eocene Liushagang Formation (E2l3) in the Huachang oil and gas field show a positive correlation with other molecular maturity indicators, such as the DNR (dimethylnaphthalene ratio), MDR (methyldibenzothiophene ratio), 4,6-/1,4-DMDBT (4,6-/1,4-dimethyldibenzothiophene), MPR (methylphenanthrene ratios), or the MPI-1 (methylphenanthrene index). The inflection of the DI-depth curve occurring at about 3200 m, corresponds to 0.55 (Ro%). The oils of the Huachang oil and gas field have higher DI values than the extracts of in situ source rocks, indicating the oils might be sourced from deeply-buried source rocks. Two petroleum systems can be distinguished in the Huachang field in terms of the relative concentration of diahopane and other maturity parameters. The oils in the upper petroleum system, consisting of the reservoirs in E 2 l 3 1 , are mainly sourced from the E2l source rocks in the Bailian sag, and are characterized by relatively higher maturity, higher oil and gas yields, and lower contents of diahopane and oleananes. The oils in the lower system, consisting of middle ( E 2 l 3 2 ) and lower units ( E 2 l 3 3 ) of E2l3, have higher contents of diahopane, higher contents of CO2 gas, and lower maturity and oil and gas yields. The occurrence and geochemical characteristics of the petroleum system are mainly controlled by the “Double Fault System” in the Huachang uplift. The C30 17α(H)-diahopane is an effective biomarker for oil–source rock correlation, oil–oil correlation, maturity assessment and petroleum system study in some terrestrial lacustrine basins.

Fluorescence reactions among Co(II), with two new 8-sulfonamidoquinoline derivatives, 5-(4-chlorophenylazo)-8-(benzenesulfonamido)quinoline (CPBSQ), and 5-(3-fluo-4-chlorophenylazo)-8-(benzenesulfonamido)quinoline (FCPBSQ), and H2O2 were investigated. CPBSQ or FCPBSQ reacted with cobalt(II) in the presence of H2O2, and basic medium forming a chelate, which exhibited intensive fluorescence in ultraviolet region. The fluorescence intensities were proportional to the concentration of cobalt(II) over the range of 0.1–100 and 0.5–200 μg/l with the detection limits of 0.05 and 0.10 μg/l for CPBSQ and FCPBSQ systems, respectively. A range of metal ions, including Cu(II) and Ni(II) did not interfere with the determinations for both systems. The methods, which are high sensitive and more selective, have been successfully applied to the determination of trace amount of cobalt in food and hair samples.

Volumetric analysis, as a simple, rapid, accurate and economic method, has been used in studying the chemical composition of Chinese neolithic age pottery. The major component analysis, principal component analysis (PCA) and artificial neural networks (ANNs) have been used to classify these potteries; the results show that they belong to three categories, the Yellow River Valley (YR) region, the Yangtse River Valley (YV) region and other region (OR). This work reveals that the ANN seems to be more suitable than PCA in classifying such archaeological samples.