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A case of bullous pilomatricoma is reported. A 22-year-old female had brown blue nodule on the right shoulder for 3 months and blisters for over 2 months. Dermatological examination revealed a demarcated 1.6 cm×1.0 cm×0.7 cm light purple semitranslucent bulla with loose wall and movable base on the right shoulder. A movable hard mass sized 0.4 cm×0.3 cm could be palpated. Histopathological examination of the lesion showed a mass with clear boundaries, and filtrates of basophils, transitional cells and shadow cells, along with proliferation and dilation of lymphatic vessels. The diagnosis was bullous pilomatricoma. Following surgical removal of the tumor, no recurrence was observed during 6 months of follow-up.

Deep buried rock is often in a non-hydrostatic initial ground stress field, and the different stress states lead to different rock response under dynamic loading. To study the dynamic behavior of rocks under coupled non-hydrostatic pressure and dynamic loading, the dynamic compression tests under different initial stress are carried out by using the split Hopkinson pressure bar (SHPB) experimental system, and the influence of different non-hydrostatic pressure on energy dissipation and failure characteristics of rock is analyzed. Based on the test results, it is found that both axial and lateral confining pressure have a significant impact on the rock dynamic strength. Taking 8 MPa as the critical point, the rock dynamic strength first increases and then decreases with the increase of axial confining pressure, but the rock dynamic strength will continue to increase with the increase of lateral confining pressure. The rock dissipative energy gradually decreases with the increase of axial confining pressure, but the trend of dissipative energy changes with confining pressure is complicated. When the axial confining pressure is low, the dissipative energy decreases with the increase of the confining pressure, and when the axial confining pressure is high, the dissipative energy shows a characteristic of increasing first and then decreasing with the increase of lateral confining pressure. According to the apparent and internal damage patterns of the specimens, combined with fractal theory and CT scanning technology, the influence of the damage pattern of rocks under different non-hydrostatic pressure conditions is analyzed. It is found that there is a significant correlation between the apparent cracks of rock and the ratio of axial-confining pressure. When the axial confining pressure ratio is low, there are fewer cracks on the side and end faces of rock. With the increase of the axial confining pressure ratio, the number of apparent cracks of rock increases. Through the analysis of the cross-sectional and vertical slices of the rock, it is found that there are circumferential and radial cracks in the rock simultaneously, and the rock failure is controlled by the penetrating shear cracks. It also can be found that the damage of rocks under non-hydrostatic pressure conditions can be divided into two parts: the central spherical rock mass and the peripheral broken rock mass, and the damage degree of rocks increases when the axial pressure increases, while the elevation of the surrounding pressure makes the damage degree of rocks decrease.

The limitation of traditional measurement technology in gas-liquid two-phase flow measurement is broken through.The liquid velocity field and vortex rope morphology from two vertical directions were measured synchronically by using particle image velocimetry and pulsed shadowgraphy technique. Experimental measurements show that the vortex rope in the draft tube presents three kinds of unstable circulation flow evolution, single spiral, double spiral, and overstocked rupture. When a single spiral vortex rope is partially split into two, it becomes a double spiral vortex rope. When the local spiral rise angle of a single spiral vortex rope decreases, it becomes an overstocked rupture. When there is a single spiral vortex rope in the draft tube, the vortex rope rotates precession around the central axis along with the liquid main flow, and the flow is divided into two parts, the outer main flow zone and the central stagnation zone, according to the axial velocity. The shear layer between the main flow zone and the stagnation zone rolls up to form several vortices. The position of liquid vortices determines the spatial morphology of the spiral vortex rope.

The research and prospecting of uranium mineralization in South China mainly focus on the Indosinian and Yanshanian granites, and a series of theoretical innovations and prospecting achievements in uranium mineralization were achieved. Miaoershan ore field is an important granitetype uranium ore field in South China, which has strong magmatic activity, the fault depression zone, structure, hydrothermal activity and alteration were widespread, the conditions for uranium mineralization are favorable. Tianmen area is located in the middle of the Miaoershan ore field. In recent years, uranium ore bodies were discovered in the Caledonian granites of this region through geological exploration. The typical samples of black massive uranium mineralization ores were collected in Tianmen area in this paper, and a variety of modern high-precision analysis methods such as optical microscope, scanning electron microscope, electron probe, comprehensive mineral analyzer and high-resolution micro-X-ray fluorescence spectrometer were used to study uranium mineral species, mineral symbiotic association, uranium mineral composition characteristics and uranium occurrence state. The results indicate that uranium minerals are mainly in the form of independent uranium minerals, such as vein and massive pitchblende and a small amount of coffinite. The composition of massive pitchblende is relatively homogeneous, and is rarely affected by significant hydrothermal alteration. Vein pitchblende is closely associated with feldspar, chlorite, calcite and rutile, and the chemical composition of them changes due to the later fluid modification. The average values of UO2, SiO2 and CaO in massive pitchblende are 83.35%, 1.45% and 7.59%, respectively, which have the characteristics of SiO2-poor, UO2-rich and CaO-rich. While the average values of UO2, SiO2 and CaO in vein pitchblende are 79.96%, 5.19% and 5.70%, respectively. In addition, coffinite is closely related to pitchblende, which may be due to the change of pH and Eh and the solubility of SiO2. With the water-rock interaction between the uranium-bearing hydrothermal solution and surrounding rock, under the influence of reducing substances (pyrite or chlorite) and weakly alkaline alteration, the ore-forming hydrothermal solution evolves in the stable physical and chemical field of coffinite and pitchblende, which resulting in the phenomenon of alternating production of coffinite and pitchblende. There are many types of paragenetic association of minerals related to the uranium mineralization, like uranium minerals-chlorite-rutile, uranium minerals-hematite-quartz-feldspar, uranium minerals-pyrite-quartz and uranium minerals-quartz-calcite four types. Comprehensive study shows that there are various mineral associations in the Caledonian granite in the Tianmen area of the Miaoershan ore field. The characteristics of uranium minerals indicate that there may be early and late hydrothermal uranium mineralization.

In order to solve the problems of ecological environment caused by the shortage of filling materials and solid wastes in the goaf of coal mine, the paper puts forward some suggestions to solve these problems, in the paper, influencing factors of paste filling body strength were analyzed, and sample strength of filling body was determined by orthogonal test, the correlation between the influence factors and the strength of the filling body was determined with grey relational analysis method, and an improved BP strength prediction model was built, in which the factors affecting the strength of solid waste paste filling are input layer and the strength of the filling body is output layer. The strength test data obtained from orthogonal test were used as training samples and test samples of the network, the fitting ability and generalization ability of network data were tested by analog simulation. Test results show that the established prediction model has fast convergence speed and high accuracy, and its prediction accuracy reaches 93.75%, which indicates accurate prediction of the filling body strength can be realized.