Lanthanide luminescent markers in hollow-point projectiles to facilitate post-mortem ballistic analysis.

Molecular dynamics simulations were applied to study the structural and transport properties, including the pair distribution function, the structure factor, the pair correlation entropy, self-diffusion coefficient, and viscosity, of liquid iron under high temperature and high pressure conditions. Our calculated results reproduced experimentally determined structure factors of liquid iron, and the calculated self-diffusion coefficients and viscosity agree well with previous simulation results. We show that there is a moderate increase of self-diffusion coefficients and viscosity along the melting curve up to the Earth-core pressure. Furthermore, the temperature dependencies of the pair correlation entropy, self-diffusion, and viscosity under high pressure condition have been investigated. Our results suggest that the temperature dependence of the pair correlation entropy is well described by T(-1) scaling, while the Arrhenius law well describes the temperature dependencies of self-diffusion coefficients and viscosity under high pressure. In particular, we find that the entropy-scaling laws, proposed by Rosenfeld [Phys. Rev. A 15, 2545 (1977)] and Dzugutov [Nature (London) 381, 137 (1996)] for self-diffusion coefficients and viscosity in liquid metals under ambient pressure, still hold well for liquid iron under high temperature and high pressure conditions. Using the entropy-scaling laws, we can obtain transport properties from structural properties under high pressure and high temperature conditions. The results provide a useful ingredient in understanding transport properties of planet's cores.

Olivine melting at high pressure condition in the chassignite Northwest Africa 2737

We review the methods of measuring the velocities of elastic-waves in rocks and summarize the temperature-dependence of elastic-wave velocities under high-temperature and high-pressure conditions. The elastic-wave velocities in rocks are strongly affected by several phenomena such as thermal cracking, phase transition of minerals, partial melting of rocks, and dehydration of hydrous minerals. These phenomena are strongly affected by pressure-temperature conditions and chemical compositions of rocks and minerals. Thus, it is very difficult to predict the elastic wave velocities of rocks and minerals under high-pressure and high-temperature conditions theoretically. Laboratory measurements of the velocities of elastic-waves in rocks under high-pressure and high-temperature conditions have provided useful data for estimating physical and geological properties in the crust and upper mantle. We also mention the next issues to be studied in relation to the velocity of elastic waves in rocks. It is important to measure elastic-wave velocities in rocks under high-temperature and high-pressure conditions in the presence of pore-fluids.

Scale prevention is one of the most important problems in the oil and gas industry. Due to the more aggressive production behavior recently, there are more chances to encounter high temperature, high pressure, and high TDS conditions. This study focuses on improving the scale prediction in the condition of high temperature (up to 210°C), and TDS (total dissolved solids, over 300,000 mg/L) with calcium concentration up to 2.0 molality (m). A hydrothermal autoclave reactor was developed for solubility measurement. The solubility of anhydrite was measured in the CaCl2-NaCl-H2O solution with constant ionic strength of 4 m. Results shows that the ionic strength effect and the Ca-SO4 association would increase the anhydrite solubility while the common ion effect decreased the anhydrite solubility. The measured solubility data can develop the virial coefficient for the ion interaction of Ca2+ and SO42. This virial coefficient can then be applied in Pitzer models to improve the calculation for the saturation index of scale. Quantifying the Ca-SO4 interaction parameters can make a better prediction of mineral solubility with high calcium concentration. The results can also improve not only anhydrite but all of the sulfate scale predictions at high temperature with high TDS conditions. This study offers a reliable and efficient method to obtain solubility under high temperature conditions and expands the scale prediction of the production brine with high calcium concentration at higher temperature and pressure limits.

A method to characterize and understand the fuel/air mixing under simulated high temperature and high pressure conditions is presented. These conditions were simulated using an isothermal liquid flow facility and model co-annular swirl burner. At increased pressures and temperatures the thermophysical properties (e.g. viscosity, vapor density) change which subsequently provides an influence on the fuel-air mixing, combustion efficiency, flame stability and generation of unwanted emissions. The results provide the effect of different flowrates and burner exit geometry (burner quads made of quartz glass) on the mixing behavior in the turbulent swirling flames. Planar laser-induced fluorescence (PLIF) diagnostics have been used to analyze the fuel-air mixing behavior under various conditions. A series of photographs of the flow field for twelve different cases have been examined. These photographs provide information on the evolutionary behavior of local and global flow structures in the flow field. Time averaged information on the flow field was obtained by averaging the desired number of photographs using an image processing software. Statistical evaluation on the scale and intensity of segregation has been determined for all cases using PLIF photographs of both the individual and time averaged results. These results provide the important role of burner geometry and flow parameters on mixing and its subsequent effect on combustion characteristics in advanced gas turbine combustors. These results provide inexpensive means of determining unmixedness and methods to improve mixedness under high pressure and high temperature gas turbine combustion conditions.

The key technology issue in deep hole drilling of hot dry rock (HDR) for geothermal energy exploitation is the stability of the surrounding rock. The temperature and in situ stress of the borehole play a significant role in its deformation and instability under high-pressure and high-temperature conditions. Based on the occurrence conditions of the granite reservoir of the Yangbajing geothermal field in Tibet, a research was conducted by means of experimental study, numerical simulation, and theoretical analysis, from which the following conclusions were drawn. (1) The deformation and failure laws of borehole are based on the physical experiment on granite specimen under high-temperature and high-pressure conditions. (2) The Weibull distribution of the thermal expansion coefficient is used for establishing rock heterogeneity, and the COMSOL software is used to reproduce the temperature and stress distribution of the borehole during physical experiment, thus demonstrating the distribution of the temperature field, stress field, and displacement field under thermo-mechanical coupling (TMC) condition. (3) Based on the complete analysis of the temperature field and stress field, combined with the conclusions of the deformation and failure of granite specimen under high-temperature and high-pressure conditions, the failure laws of borehole under the TMC condition were analyzed, as well as the critical conditions of borehole instability during deep hole drilling of HDR. (4) With the critical conditions of borehole instability during deep hole drilling of HDR, which the relation between the in situ stress σ and temperature T is σ = 241.9–0.3998 T. These conclusions have practical guiding significance to the stability control of the surrounding rocks of borehole in relation to projects such as geothermal energy exploitation from HDR, deep oil and gas resource extraction, and deep hole drilling in mainland China.

Hot Gas Desulfurizarion for IGCC is a new method to efficiently remove H2S in fuel gas with regenerable sorbents at high temperature and high-pressure conditions. The Korea Institute of Energy Research did operation of sulfidation in a desulfurizer and regeneration in a regenerator simultaneously at high pressure and high temperature conditions. The H2S concentration at exit was maintained continuously below 50ppmv at 11,000 ppmv of inlet H2S concentration. The sorbent had little effect on the reducing power in the inlet gas in the range from 11% to 33% of H2. As inlet H2S concentration was increased, H2S concentration in the product gas was also increased linearly. The sorbent was maintained at low sulfur level by the continuous regeneration and the continuous solid circulation at the rate of 1.58× 10−3 kg/s with little mean particle size change.

As a lesson learned from the Fukushima nuclear power plant accident, the industry recognized the importance of mitigating accident consequences after Beyond Design Basis Events (BDBE). We propose the concept of applying fracture control to mitigate failure consequences of nuclear components under BDBE. This paper discusses example applications of our proposed method to vessels and piping. As an example for vessels, the fracture controlled method of a fast reactor vessel was proposed to maintain coolant under high pressure and high temperature conditions. One of the important accidents to consider is fuel criticality upon a core meltdown. This accident will cause high temperature and high pressure conditions in the vessel. To maintain coolant to cover the fuel under above conditions, strength of the upper part of a vessel is controlled to be weaker than the lower part. When the upper parts fail, internal pressure will be released and the lower part will be protected. Coolant of fast reactors is liquid metal with a high boiling point. Therefore, there is no boiling when the pressure drops. As a result, the coolant stays within the vessel for continuous cooling after accidents. If nozzles penetrate only the upper part of a vessel, controlling strengths at the structural discontinuities can realize the proposed method. As a piping example, the fracture controlled method of main steam piping of a BWR was proposed to avoid collapse and break under excessive earthquake. The piping is constrained by supports to the building. Strength of piping supports should be weaker than that of the piping. If piping supports break before the piping, natural frequencies of piping decrease increasing the frequency ratios. When their frequency ratios are larger than one, the seismic energy hardly transfers to the piping and the piping will not collapse or break. When the primary stresses from dead weight are not negligible, simple supports by wire are enough to protect piping against dead weight.

The following study presents the results of research in the field of the performance of geopolymers consisting of Class F fly ash with an alkaline activator solution consisting only of sodium metasilicate (Na2SiO3) and water. The performances of this geopolymer are compared to the those of American Petroleum Institute (API) Class G cement. This comparison is to evaluate the potential of the geopolymer as an alternative to cement in cementing hydrocarbon wells in the oil and gas industry. The gap in the research is determining the performance properties that restrict the use of fly ash in the oil and gas industry. Using only sodium metasilicate as an activator with water, the solution creates a strong binding gel for the geopolymer and activates the aluminosilicate properties of the fly ash. This geopolymer is compared with Class G cement without additives to determine their base performances in high pressure and high temperature conditions, as well as note any properties that are affected in the process. This commences by formulating recipes of these two materials from workable ratios and concentrations. The ratios are narrowed down to the best working models to proceed to comparative performance testing. The tests included exploring their vital performances in fluid loss and thickening time. The results produced suggest that Class G cement generally has less fluid loss at low temperature than the geopolymer but could not maintain its integrity and structure as temperatures increased. Class G cement exhibited stability, consistencies of 100 Bcs (Bearden Consistency Units), and a faster thickening time of 1 h and 48 min when placed under high temperature and high-pressure conditions, respectively. However, the geopolymer showed more consistency regarding fluid loss with respect to rising pressure and temperature, and smoother, less fractured samples emerging from both tests. Though the geopolymer showed stronger performances in thickening and water retention, the experiments showed that it is not a uniform and consistent material like Class G cement. Through the use of different additives and intricate design, the sample may show success, but may prove more difficult and complex to apply than the industry standard and uniform content of Class G cement.

Mercury loss and isotope fractionation during high-pressure and high-temperature processing of sediments: Implication for the behaviors of mercury during metamorphism

A large volume cubic anvil press integrated with synchrotron energy-dispersive x-ray diffraction was employed to study the yielding behavior of powdered beta silicon carbide (SiC) under high pressure and high temperature conditions up to 7.4 GPa and 1400 °C. During compression and heating, the x-ray pattern was collected at each pressure–temperature point, and, then, via assessing the peak width of the x-ray diffraction pattern, the strains/stresses developed inside the sample under varied pressure–temperature conditions were determined. From the constitutive response of the sample as a function of pressure and temperature, we did not observe the yielding occurrence in SiC at cold compression. In contrast, high temperature induces a yielding at 1100 °C with a constant loading pressure of ∼7.4 GPa. By comparison, we found that this material is the most stable, compared with the other three strong ones (diamond, moissanite, and alfa silicon nitride), in terms of the yielding under high pressure and temperature conditions. Along with its much higher pressure and temperature requirements for phase transition and decomposition, SiC is a competent material for the development of novel tools/devices to be used in the harshly extreme working environment, such as deep drilling, high-speed cutting, and aerospace engineering.

Environmental risk assessment is generally based on atmospheric conditions for the modelling of chemical fate after entering the environment. However, during hydraulic fracturing, chemicals may be released deep underground. This study therefore focuses on the effects of high pressure and high temperature conditions on chemicals in flowback water to determine whether current environmental fate models need to be adapted in the context of downhole activities. Crushed shale and flowback water were mixed and exposed to different temperature (25–100 °C) and pressure (1–450 bar) conditions to investigate the effects they have on chemical fate. Samples were analysed using LC-HRMS based non-target screening. The results show that both high temperature and pressure conditions can impact the chemical fate of hydraulic fracturing related chemicals by increasing or decreasing concentrations via processes of transformation, sorption, degradation and/or dissolution. Furthermore, the degree and direction of change is chemical specific. The change is lower or equal to a factor of five, but for a few individual compounds the degree of change can exceed this factor of five. This suggests that environmental fate models based on surface conditions may be used for an approximation of chemical fate under downhole conditions by applying an additional factor of five to account for these uncertainties. More accurate insight into chemical fate under downhole conditions may be gained by studying a fluid of known chemical composition and an increased variability in temperature and pressure conditions including concentration, salinity and pH as variables.

To study the chemical changes of salvianolic acid B and lithospermic acid of Salvia miltiorrhiza under the conditions of high temperature and high pressure and explore the reaction mechanism. S. miltiorrhiza extracts, salvianolic acid B and lithospermic acid were put in the reactor under the conditions of high temperature and high pressure (120 degrees C, 0.2 MPa), and the chemical changes and stability was studied. Salvianolic acid A was the primary product in salvianolic acid B and lithospermic acid's conversion process, and lithospermic acid was an intermediate in the conversion process of salvianolic acid B. Compared with salvianolic acid B, lithospermic acid could convert into more salvianolic acid A and fewer other products in the same conditions. Salvianolic acid A was not stable under the conditions of high temperature and high pressure, and could sequentially convert into other small molecules. Referring to the chemical conversion of salvianolic acid B and lithospermic acid, a method of large-scale preparation of salvianolic acid A can be developed.

The supercritical water reactor (SCWR), which is one of the generation IV reactor concepts, has particular thermal hydraulics features. If a severe accident happens and pressure and mass flux in a reactor core are rapidly decreased, a film boiling on a fuel cladding tube surface may occur at subcritical conditions. Once the film boiling happens, heat transfer on the cladding tube surface drastically deteriorated and may result in serious damage to the reactor core. The cooling capability during the film boiling depends on the wetting phenomenon, therefore, experiments to clarify wettability phenomenon in subcritical condition are required. One of the experiments to clarify the wettability phenomenon is the capillary action experiment. In the closed system, the water level will elevate due to the injection of the water. The difference in water elevation is due to the capillary force in the different diameter of the pipes. Based on the different water levels with known surface tension, it is possible to quantify the contact angle. The challenge of the experiment is to measure the precise elevation of the water in small diameter metal pipes under high-temperature and high-pressure condition. Therefore, the neutron imaging was applied in this experiment. Neutron imaging is a structure visualization technique. The principle is the neutron flux captured after passing through the object for visualizing the structure of an object. Neutron flux which is captured using a scintillator plate thus can be seen as an image using CCD video camera. Our research group focuses on the radiation induced surface activation (RISA) effect. Significant improvements of surface wettability and boiling heat transfer on oxide film coatedmaterials by the RISA were confirmed especially under room temperature conditions. In this present research, we evaluate the RISA effect on capillary action in a subcritical condition using the various diameter of the pipe. Neutron imaging was used to visualize the water-gas interface in small diameter stainless steel pipes. The capillary pipes with various inside diameters such as 0.5, 0.8, 1.2, 1.4, and 1.8 mm were used as a test section which was heated up to a temperature of 320° C under a pressure of 21 MPa. The pipes irradiated by γ-ray with an integrated irradiation dose of approximately 500 kGy and non-irradiated pipes with various diameters are installed in parallel and water levels in each pipe were compared to evaluate capillary action differences.

<sec>When an incident high-energy heavy ion beam enters into solid material, the energy deposition density along the ion flight path can change the temperature and pressure of macroscopic target, and new material defects can be created under the high-pressure and high-density conditions. To accurately control the extreme state in material generated by heavy ion beam, it is necessary to conduct in-depth research on the energy deposition density of ions and ascertain the new potential defects in matter. Reported in this work is the new experiment conducted on the HIRFL-CSR at Lanzhou, with the extracted 264 MeV/u Xe<sup>36+</sup> ion beams irradiating an LiF crystal target. The emission spectrum of the LiF is measured <i>in-situ</i>. Moreover, the crystal color is observed to vary along the ion path, and X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) are used to observe the potential new phases at different positions of crystal through the target dissociation method.</sec><sec>It is apparent that in No. 3-front a new phase around 52.6° is found in XRD result, which is believed to be LiF<sub>3</sub> (LiF+F<sub>2</sub>) structural phase and appears in the Bragg peak region of Xe ions in LiF. Furthermore, to verify this result, a similar experiment is done by using a 430 MeV/u <sup>84</sup>Kr<sup>26+</sup> ion beam, and the stacked layered LiF target is analyzed after the irradiation. The XPS result shows more complex defects aggregating in the Bragg peak region of Kr ions in LiF at room temperature. In previous study, such complex defects were all created under high temperature conditions. We find that these complex defects can be produced around the Bragg peak region of ions in LiF at room temperature, resulting in a temporally high temperature and high pressure condition. This paper can provide some experimental evidences and references for the target material modification in heavy ion beam driven high-energy density physics research.</sec>