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Pervasive dolomites occur preferentially in the stromatoporoid biostromal (or reefal) facies in the basal Devonian (Givetian) carbonate rocks in the Guilin area, South China. The amount of dolomites, however, decreases sharply in the overlying Frasnian carbonate rocks. Dolostones are dominated by replacement dolomites with minor dolomite cements. Replacement dolomites include: (1) fine to medium, planar-e floating dolomite rhombs (Rd1); (2) medium to coarse, planar-s patchy/mosaic dolomites (Rd2); and (3) medium to very coarse nonplanar anhedral mosaic dolomites (Rd3). They post-date early submarine cements and overlap with stylolites. Two types of dolomite cements were identified: planar coarse euhedral dolomite cements (Cd1) and non-planar (saddle) dolomite cements (Cd2); they post-date replacement dolomites and predate late-stage calcite cements that line mouldic vugs and fractures. The replacement dolomites have d 18 O values from )13AE7 to )9AE7& VPDB, d 13 C values from )2AE7 to + 1AE5& VPDB and 87 Sr/ 86 Sr ratios from 0AE7082 to 0AE7114. Fluid inclusion data of Rd3 dolomites yield homogenization temperatures (T h ) of 136-149°C and salinities of 7AE2-11AE2 wt% NaCl equivalent. These data suggest that the replacive dolomitization could have occurred from slightly modified sea water and/or saline basinal fluids at relatively high temperatures, probably related to hydrothermal activities during the latest Givetian-middle Fammenian and Early Carboniferous times. Compared with replacement dolomites, Cd2 cements yield lower d 18 O values ()14AE2 to )9AE3& VPDB), lower d 13 C values ()3AE0 to )0AE7& VPDB), higher 87 Sr/ 86 Sr ratios ( 0AE7100) and higher T h values (171-209°C), which correspond to trapping temperatures (T r ) between 260 and 300°C after pressure corrections. These data suggest that the dolomite cements precipitated from higher temperature hydrothermal fluids, derived from underlying siliciclastic deposits, and were associated with more intense hydrothermal events during Permian-Early Triassic time, when the host dolostones were deeply buried. The petrographic similarities between some replacement dolomites and Cd2 dolomite cements and the partial overlap in 87 Sr/ 86 Sr and d 18 O values suggest neomorphism of early formed replacement dolomites that were exposed to later dolomitizing fluids. However, the dolomitization was finally stopped through invasion of meteoric water as a result of basin uplift induced by the Indosinian Orogeny from the early Middle Triassic, as indicated by the decrease in salinities in the dolomite cements in veins (5AE1-0AE4 wt% NaCl equivalent). Calcite cements generally yield the lowest d 18 O values ()18AE5 to )14AE3& VPDB), variable d 13 C values ()11AE3 to )1AE2& VPDB) and high T h values (145-170°C) and low salinities (0-0AE2 wt% NaCl equivalent), indicating an origin of high-temperature, dilute fluids recharged by meteoric water in the course of basin uplift during the Indosinian Orogeny. Faults were Sedimentology

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The conductance method has been used to measure the density of interface states of the ZnS/Hg0.775Cd0.225Te metal-insulator-semiconductor (MIS) system with three different HgCdTe surface treatments. It is found that the density of fast interface states increases from ∼1011 eV−1 cm−2 at the conduction-band minimum to ∼1013 eV−1 cm−2 near the valence-band maximum. In addition, the interface states located in the lower part of the band gap communicate with the valence band so efficiently that the effective band gap is reduced. Our observations explain why the p-type MIS photodiode is superior to the n-type version in terms of breakdown voltage and storage time.

Limestone consisting of finely to medium crystalline calcite mosaics is present in the upper part of the Winnipegosis Formation on the east‐central margin of the Elk Point Basin where the overlying Prairie Evaporite deposits have been removed. This type of crystalline limestone is interpreted as dedolomite, based on petrographic observations. The δ18O and δ13C values of the Winnipegosis dedolomite vary from −12·8‰ to −11·9‰ VPDB (Vienna Pee Dee Belemnite) and from −0·5‰ to +1·7‰ VPDB, respectively; both values are significantly lower than those for the corresponding dolomite. The 87Sr/86Sr ratios of the dedolomite are significantly higher, between 0·7082 and 0·7087. The spatial distribution and geochemical data of the Winnipegosis dedolomite suggest that dedolomitization was related to an influx of fresh groundwater and dissolution of the Prairie Evaporite anhydrite during the latest Mississippian to the Early Cretaceous when the basin was subjected to uplift and erosion. The Winnipegosis dedolomite displays a series of replacement fabrics showing progressive calcitization of dolomite, including the occurrence of dedolomite restricted along fractures and adjacent areas, dolomite patches ‘floating’ in the dedolomite masses and massive dedolomite with sparsely scattered dolomite relicts. However, the characteristic fabrics resulting from dedolomitization documented in the literature have not been observed in the Winnipegosis dedolomite. Coarsely to very coarsely crystalline, subhedral to euhedral calcite cement is restricted in the dedolomite. The petrographic features, isotopic compositions and homogenization temperatures, coupled with the burial history of the Winnipegosis Formation, constrain the precipitation of the calcite cement from a mixing of basinal brines and fresh groundwater during Late Cretaceous to Neogene time. The more negative C‐isotopic signatures of the calcite cement (−5·3‰ to −2·3‰ VPDB) probably reflect a hydrocarbon‐derived carbon.

Triaxial unloading creep tests of layered rock specimen of Jinping II hydropower station were carried out using the rock creep testing machine; thus the creep deformation curves under different confining pressures were acquired. The test results showed that, in addition to the obvious unloading creep characteristics of rock specimen, the nonlinear accelerating creep deformation emerged under the last stage confining stress condition, and the whole creep curves presented the typical rock creep three stages. On the other hand, the Burgers creep model constitutive equations under the three-dimensional stress state were also deduced. Based on the creep test data, through identifying the creep parameters using the optimized algorithm, the corresponding parameters of triaxial creep constitutive model were obtained. By comparative analysis of creep parameters, it can be concluded that creep parameters nonlinearly degraded with the decrease of confining pressure gradually. Moreover, when the load is below the long-term strength of rock, the creep parameters are only related to the unloading ratio, while in the case that the load is larger than the long-term strength of rock, the unloading creep parameters are related to both unloading ratio and creep time. According to the creep parameters under the first-stage stress level, and through introducing unloading ratio damage factor to describe the degrading rule of creep parameters on other stress levels, the method of uniformity determining the creep parameters was proposed. It was assumed that the damage degree in rock interior was relative to both unloading ratio and creep time; a nonlinear creep damage model of rock under unloading was proposed, which could better reflect the nonlinear characteristics of rock creep. The results showed that rock nonlinear creep damage model achieved perfectly consistent results with the creep test.

This work presents a brief introduction on the basics of fiber-optical sensors and an overview focused on the applications to measurements in multiphase reactors. The most commonly principle utilized is laser back scattering, which is also the foundation for almost all current probes used in multiphase reactors. The fiber-optical probe techniques in two-phase reactors are more developed than those in three-phase reactors. There are many studies on the measurement of gas holdup using fiber-optical probes in three-phase fluidized beds, but negative interference of particles on probe function was less studied. The interactions between solids and probe tips were less studied because glass beads etc. were always used as the solid phase. The vision probes may be the most promising for simultaneous measurements of gas dispersion and solids suspension in three-phase reactors. Thus, the following techniques of the fiber-optical probes in multiphase reactors should be developed further: (1) online measuring techniques under nearly industrial operating conditions; (2) corresponding signal data processing techniques; (3) joint application with other measuring techniques.