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[Objective] Jiaojia-type gold deposit is a new type of gold mine discovered by Shandong geologists in northwestern Jiaodong in the 1960s, and its output is controlled by regional tectonic fracture zones. Pyrite sericitized alteration generally occurred during the ore-forming period, which is characterized by a large scale, distinct alteration zones, concentration of mineralization, simple morphology of the ore body, relatively uniform grade, and simple mineral combinations. The deposit has gone through 12 years of exploration and scientific research, from discovery to establishment. [Methods] This new type of gold deposit has been rapidly promoted since its establishment and has achieved fruitful prospecting results in China. Deep exploration achievements of the Jiaojia-type gold deposit have been coming up in the Jiaodong area since the 21st century. [Results] The accumulated gold resource reserves submitted have been 3617.12 tons by 2020, which has helped the Jiaodong area become the third largest gold cluster in the world, and gold reserves of China have risen to the second rink in the world. Research on the Jiaojia-style gold mine has also made considerable progress, with the age of mineralization accurately limited to 126~120 Ma and formation occurring under a strong regional extension background. The source of mineralization material has multiple origins, with the Archean tholeiite being the initial source rock of gold-bearing minerals. The ore-forming process is divided into four stages, and the “thermo-extension”metallogenic theory and the step metallogenic model are proposed. The metallogenic depth is about 5~10 km, and the post-metallogenic denudation thickness is 5.2±1.2 km, with the deposits well preserved. [Conclusion] The metallogenic prediction study concluded that the total gold resources in the three major metallogenic zones of Sanshandao, Jiaojia, and Zhaoping in the northwestern Jiaozhou area were 7258~10150 tons of metal at a depth of 5000 m, which demonstrates the immense potential of the deeper part of the Jiaojia-type gold deposits for exploration. A set of key exploration techniques was summarized for different exploration stages, from shallow to deep. [Significance] These studies enriched the metallogenic theory of the Jiaojia-type gold deposit, making the metallogenic prediction results highly accurate, reliable, and effective in guiding the gold exploration in the Jiaodong peninsula.

In order to realize stable propagation of the ethylene-air rotating detonation wave with less velocity deficit in the annular combustion chamber, a series of experiments have been carried out while changing the combustor width (i.e. 10 mm, 15 mm, 25 mm, and a hollow combustor), mass flow rate of air, and equivalence ratio. The air and ethylene are supplied into the combustor through a slot-orifice impinging injection scheme, where air is injected through a slot with a height of 0.5 mm and ethylene is supplied by 160 orifices with a diameter of 0.35 mm. Experimental results indicate that four propagation modes have been obtained, i.e. the single wave mode, the sawtooth wave mode, the periodic oscillation mode, and the deflagration mode. The sawtooth wave mode and the periodic oscillation mode are considered unstable modes. In the single wave mode, the average propagation velocity of rotating detonations in the annular combustion chamber with a combustor width of 15 mm is between 1121 and 1215 m/s. The minimum velocity deficit is 21.9%, and the relative standard deviation of the propagation velocity is less than 5%, which is much lower than the experimental results of other studies utilizing ethylene and air in the annular combustors. In addition, the reasons may lead to the failure of producing rotating detonations have been analyzed. The effects of the chemical reactivity on the generation of rotating detonation waves have been demonstrated by installing a convergent nozzle at the exit of the combustor. [ABSTRACT FROM AUTHOR]

Objectives: This study examined the effect of a 4-week unsweetened cranberry beverage (CRAN) (317 mg polyphenols) versus placebo beverage (PLAC) ingestion (240 mL/day) on moderating exercise-induced changes in innate immunity. Methods: Participants included 25 male and female non-elite cyclists. A randomized, placebo-controlled, double-blind crossover design was used with two 4-week supplementation periods and a 2-week washout period. Supplementation periods were followed by an intensive 2.25 h cycling bout. Six blood samples were collected before and after supplementation (in an overnight fasted state) and at 0 h, 1.5 h, 3 h, and 24 h post-exercise. Stool and urine samples were collected pre- and post-supplementation. Outcome measures included serum creatine kinase, myoglobin, and cortisol, complete blood counts, plasma untargeted proteomics, plasma-targeted oxylipins, untargeted urine metabolomics, and stool microbiome composition via whole genome shotgun (WGS) sequencing. Results: Urine CRAN-linked metabolites increased significantly after supplementation, but no trial differences in alpha or beta microbiota diversity were found in the stool samples. The 2.25 h cycling bout caused significant increases in plasma arachidonic acid (ARA) and 53 oxylipins (FDR q-value < 0.05). The patterns of increase for ARA, four oxylipins generated from ARA-cytochrome P-450 (CYP) (5,6-, 8,9-, 11,12-, and 14,15-diHETrEs), two oxylipins from linoleic acid (LA) and CYP (9,10-DiHOME, 12,13-DiHOME), and two oxylipins generated from LA and lipoxygenase (LOX) (9-HODE, 13-HODE) were slightly but significantly higher for the CRAN versus PLAC trial (all interaction effects, p < 0.05). The untargeted proteomics analysis showed that two protein clusters differed significantly between the CRAN and PLAC trials, with CRAN-related elevations in proteins related to innate immune activation and reduced levels of proteins related to the regulation of the complement cascade, platelet activation, and binding and uptake of ligands by scavenger receptors. No trial differences were found for cortisol and muscle damage biomarkers. Conclusions: CRAN versus PLAC juice resulted in a significant increase in CRAN-related metabolites but no differences in the gut microbiome. CRAN supplementation was associated with a transient and modest but significant post-exercise elevation in selected oxylipins and proteins associated with the innate immune system. [ABSTRACT FROM AUTHOR]

The purpose of this paper is to study a predator–prey model with Allee effect and double time delays. This research examines the dynamics of the model, with a focus on positivity, existence, stability and Hopf bifurcations. The stability of the periodic solution and the direction of the Hopf bifurcation are elucidated by applying the normal form theory and the center manifold theorem. To validate the correctness of the theoretical analysis, numerical simulations were conducted. The results suggest that a weak Allee effect delay can promote stability within the model, transitioning it from instability to stability. Nevertheless, the competition delay induces periodic oscillations and chaotic dynamics, ultimately resulting in the population's collapse. [ABSTRACT FROM AUTHOR]

As the pressure ratio and the turbine inlet temperature keep increasing in high performance aero-engines, the kerosene injected into the combustion chamber becomes supercritical. Thus, the traditional self-excited oscillations of the kerosene jets in the fuel–gas mixing are much more pronounced because of the drastic changes in the kerosene thermal properties, which may exacerbate the combustion instability and threaten engine efficiency and safety. In this work, an experimental study was carried out on the self-excited oscillation phenomena of supercritical kerosene injected into a swirling flow field. The injection of supercritical kerosene under different operating conditions was studied using the Schlieren technique and the proper orthogonal decomposition method. The results present that the mixing dominated oscillations of the kerosene jet are induced by the fuel–gas interaction. While the condensation dominated oscillations are due to the phase change of supercritical kerosene in the subcritical environment and the swirling flow field. The spatial distribution of the self-excited oscillations is found to be highly related to the velocity magnitude, instead of the variations in the injection temperature and pressure. The self-excited oscillations are easier to be induced in a low velocity flow field and the oscillation region moves closer to the upstream. Thermal properties also show distinct influences on the injection. At the near-critical region, the suppression effects of high injection pressure on the high-frequency (>100 Hz) self-excited oscillations are much more distinct. [ABSTRACT FROM AUTHOR]