The anti-corrosion and robust superhydrophobic stainless surface is obtained by nanosecond laser direct writing.

JUNO is a massive liquid scintillator detector with a primary scientific goal of determining the neutrino mass ordering by studying the oscillated anti-neutrino flux coming from two nuclear power plants at 53 km distance. The expected signal anti-neutrino interaction rate is only 60 counts per day (cpd), therefore a careful control of the background sources due to radioactivity is critical. In particular, natural radioactivity present in all materials and in the environment represents a serious issue that could impair the sensitivity of the experiment if appropriate countermeasures were not foreseen. In this paper we discuss the background reduction strategies undertaken by the JUNO collaboration to reduce at minimum the impact of natural radioactivity. We describe our efforts for an optimized experimental design, a careful material screening and accurate detector production handling, and a constant control of the expected results through a meticulous Monte Carlo simulation program. We show that all these actions should allow us to keep the background count rate safely below the target value of 10 Hz (i.e. ∼1 cpd accidental background) in the default fiducial volume, above an energy threshold of 0.7 MeV.

Denggezhuang gold deposit is an epithermal gold-quartz vein deposit in northern Muru gold belt, eastern Shandong, China. The deposit occurs in the NNE-striking faults within the Mesozoic granite. The deposit consists of four major veins with a general NNE-strike. Based on crosscutting relationships and mineral parageneses, the veins appear to have been formed during the same mineralization epochs, and are further divided into three stages: (1) massive barren quartz veins; (2) quartz-sulfides veins; (3) late, pure quartz or calcite veinlets. Most gold mineralization is associated with the second stage. The early stage is characterized by quartz, and small amounts of ore minerals (pyrite), the second stage is characterized by large amounts of ore minerals.Fluid inclusions in vein quartz contain C-H-O fluids of variable compositions. Three main types of fluid inclusions are recognized at room temperature: type I, two-phase, aqueous vapor and an aqueous liquid phase (L+V); type II, aqueouscarbonic inclusions, a CO 2 -liquid with/without vapor and aqueous liquid (LCO 2 +VCO 2 +Laq.); type III, mono-phase aqueous liquid (Laq.). Data from fluid inclusion distribution, microthermometry, and gas analysis indicate that fluids associated with Au mineralized quartz veins (stage 2) have moderate salinity ranging from 1.91 to 16.43 wt% NaCl equivalent (modeled salinity around 8-10 wt% NaCl equiv.). These veins formatted at temperatures from 80°to 280°C. Fluids associated with barren quartz veins (stage 3) have a low salinity of about 1.91 to 2.57 wt% NaCl equivalent and lower temperature. There is evidence of fluid immiscibility and boiling in ore-forming stages.Stable isotope analyses of quartz indicate that the veins were deposited by waters with δ 18 O and δD values ranging from those of magmatic water to typical meteoric water. The gold metallogenesis of Muru gold belt has no relationship with the granite, and formed during the late stage of the crust thinning of North China.

Precast reinforced concrete structures are widely used due to many constructional advantages such as faster construction speed, lower construction cost, being environmentally friendly, higher strength, and so on. To study the seismic performance of precast reinforced concrete structures, tests on beam-to-column joints of precast reinforced concrete structures were conducted under low reversed cyclic loading. In total, four joint specimens were produced in this study, including two precast joints and two cast-in-place joints. In addition to the comparison between different types of joints, the axial compression ratio of column was adopted as the main variable in this study. Analysis was carried out on the basis of the observed joint failure mode and relationships derived from the test data such as hysteresis curves, skeleton curves, stiffness degradation curves, energy dissipation capacities, and sleeve joint strain curves. Despite the closeness of energy dissipation capacity between the precast joints and the cast-in-place joints, they had different failure modes. Precast joints feature a relatively concentrated crack distribution in which the limited number of cracks was distributed throughout the plastic zone of the beam. Cast-in-place joints feature more evenly distributed cracks in the plastic zone, especially at the later stage of the loading. The steel slippage of the precast concrete joints was found influenced by the axial compression ratio. Through this study, it is concluded that seismic resistance capacity of precast concrete joint needs to be considered in design and construction and the grouting sleeve splice could be kept away from the hinge zones when precast concrete structures were used in regions of high seismicity. The results in this study can provide a theoretical basis for seismic design of precast reinforced concrete structures, which in turn can promote the application of precast reinforced concrete structures.

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