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ObjectiveThis study aimed to assess control measures regarding the epidemiological characteristics of food-borne disease outbreaks to guide future prevention measures and treatment methods.MethodsDescriptive epidemiological methods were used to retrospectively investigate poisoning events， and epidemiological characteristics were analyzed.ResultsA total of 55 incidents and three deaths were reported， of which 60% were in individuals aged over 50 years. The incidents were all caused by family meals， exhibiting distinct family clustering. The main clinical manifestations were abnormal liver function （54 cases， 98.2%）， nausea （36 cases， 65.5%）， fatigue （29 cases， 52.7%）， and partial numbness of the mouth and lip extremities （9 cases， 16.4%）. The food suspected to cause the disease was Bullacta exarata， of which paralytic shellfish poisoning was detected in six samples. After taking comprehensive prevention and control measures， the incident was brought under control.ConclusionThis is a food poisoning case study caused by the consumption of paralytic shellfish-poisoned snails. The presence of other pathogenic factors cannot be ruled out. It is suggested that related departments should strengthen education and monitor early warning symptoms.

The dynamic evolution in friction and wear can lead to interface failure and induce vibrations in pipeline inspection gauge. The friction behavior between polyurethane and X70 steel was evaluated with annular face contact under 0.042 to 0.07 MPa. The temperature increase was recorded using infrared cameras. Dynamic simulations of frictional heat and stress-strain were conducted using Abaqus software. The results indicate that in the initial stages, abrasive wear, stress (1.5 MPa), and frictional temperature rise (65 °C) of PU were observed in the inner-ring region at 0.056 MPa. The surface roughness (3.394 μm) of the PU became comparable to that of the steel ring (3.768 μm) due to abrasive wear. In the later stages, a higher frictional temperature (80 °C) and increased stress (3.8 MPa) were observed in the outer ring. Concurrently, Schallamach waves and ridge-like stripes indicative of stick-slip behavior emerged in the outer ring. The viscoelastic hysteresis effect is the fundamental cause of the dynamic evolution of the friction coefficient and wear. Frictional heat exacerbates the evolution of stick-slip behavior and increases fluctuations in the friction coefficient. The findings of this research can be utilized to analyze the causes of interface failure and vibration in pipeline inspection gauge. [ABSTRACT FROM AUTHOR]

The change of iron grade in the leaching residue and the leaching kinetics under normal pressure and pressure were examined. The pressure leaching of nickel and cobalt from a high iron and low grade laterite nickel ore in Indonesia with sulfuric acid was studied. The results show that under the conditions of acid/ore ratio of 260 kg/t, leaching temperature of 250 °C (corresponding to water vapor pressure of 4. 0 MPa), liquid volume/solid mass ratio of 3/1, stirring speed of 300 r/min, particle size of 100 mesh and reaction time of 1 h, the leaching rates of nickel, cobalt and iron are 98. 1 %, 98. 3% and 4. 7%, respectively, and the iron grade can reach 51. 3%. The leaching processes of nickel and cobalt under pressure and atmospheric pressure are in line with the shrinkage kernel model of interfacial chemical reaction control, and the activation energies of the reactions are 116 kj/mol and 91 kj/mol under pressure, respectively, and the activation energies of the reaction under atmospheric pressure are 41 kj/mol and 53 kj/mol, respectively. The leaching is mainly goethite under normal pressure, and chromite, magnetite and other mineral phases under high pressure. [ABSTRACT FROM AUTHOR]

The removal of fluorine from high fluorine manganese sulfate solution by lanthanum oxide was studied. The effects of initial solution pH, the amount of lanthanum oxide, reaction temperature, reaction time and stirring speed on the removal rate of fluorine were investigated. The defluorinated products were characterized by XRD and EDS. The results show that for the high fluoride manganese (II) sulfate solution with the fluoride ion mass concentration of 1 260 mg/L, the fluoride mass concentration is reduced to 10 mg/L and the fluoride removal rate is 99.93% under the conditions of initial solution pH = 3, lanthanum oxide amount of three times of the theoretical amount, reaction temperature of 55 °C, reaction time of 40 min, and stirring speed of 250 r/min. The fluorine mass concentration in manganese sulfate products is less than 14 mg/L, which can meet the requirements of preparing high-purity manganese (II) sulfate. This method has remarkable effect on defluorination of high fluoride manganese sulfate solution. [ABSTRACT FROM AUTHOR]

The effect of friction stir processing (FSP) on the microstructure, mechanical properties, and damping properties of as-cast Al-5Fe alloy was investigated. The results showed that the needlelike or rod-like eutectic Fe-rich phases were broken into fine particles and homogeneously distributed on the Al matrix with fine equiaxed recrystallized grains with the size of 2–5 μm in the stir zone after FSP. The hardness distribution in the as-cast alloy is highly dispersed. The strength, ductility increased simultaneously after FSP. The increase in the tensile strength values was about 15.6% after FSP. The FSPed alloy exhibited higher elongation to fracture of about 27.5% in comparison with the as-cast sample having only 3.7%. Meanwhile, FSP can obviously improve the damping properties of the Al-5Fe alloy. [ABSTRACT FROM AUTHOR]