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K403 nickel-base superalloy is widely used in the manufacture of aero-engine turbine blades because of its excellent properties at room temperature and high temperature. In order to solve the problem of turbine blade crack defects caused by long-term service in complex working conditions，in this work，two different processes of （tungsten inert gas，TIG） welding and laser cladding were used to repair the blade cracks，and the microstructure and properties of the repaired region were studied. The influence of TIG welding and laser cladding repairing on microstructure，mechanical properties and failure behavior was analyzed. The results show that the microcracks tend to occur near the repair interface using the TIG welding repairing process，which are mainly caused by carbides and low melting point eutectic structure. The grain and structure of the repaired area by laser cladding repair technology are more uniform，and the microcrack defects can be easier to control. The comprehensive mechanical properties of the samples repaired by laser cladding are obviously higher than those repaired by TIG welding repairing process，and the samples repaired by laser cladding have better process stability. The tensile strengths of the samples using the laser cladding repair process and the TIG welding repair process at room temperature have reached 87.44% and 69.22% of the strength of K403 base material，respectively. According to the failure analysis results，the tensile fracture at room temperature in the repaired region presents mixed fracture characteristics，and the tensile fracture at high temperature presents intergranular fracture characteristics. Microcracks in the repaired area，local liquid phase deficiency defects and carbide structure are the main reasons of failure. The laser cladding technology has the advantages of heat source concentration and smaller heat affected zone，which can effectively restrain the defects and refine the microstructure. Therefore，the laser cladding repair process is used to repair the edge plate crack damage generated during the blade test run. After fluorescence and kerosene-chalk detection，the repairing process meets the relevant reuse requirements.

Selective laser melting（SLM）can achieve nearly net-shape complex parts of GH3536 alloy，and its high temperature mechanical properties are important indicators for safe service. The effect of heat treatment on microstructure and high temperature tensile properties of SLM GH3536 alloy were studied. The heat treatment at 1225 ℃ for 1 h was carried out to explore the regulation mechanism of microstructure and properties. The results show that heat treatment can effectively eliminate the cellular subgrain structure inside the grains，which significantly enhances the dislocation slip ability. The tensile elongations at room temperature，650 ℃ and 815 ℃ are increased by 75%，92% and 683%，respectively. In addition，the decrease of the aspect ratio of the columnar grains significantly reduces the anisotropy in the heat-treated sample. The fracture analysis shows that the fracture mode of the heat-treated sample changes from intergranular fracture to mixed fracture with the increase of tensile environment temperature.

Background As socioeconomic status and population health develop, death patterns and disease spectrum have changed. The impact of diseases on life expectancy have changed as well. Objective To analyze the change in life expectancy and disease spectrum in residents of Jing'an District in Shanghai from 2016 to 2021. Methods Population data and mortality data of permanent residents in Jing'an District of Shanghai from 2016 to 2021 were collected from the Public Security Bureau of Jing'an District, and the Jing'an District Mortality Surveillance System. The ICD-10 was used to categorize the underlying causes of death. The Abridged Life Tables and Arriaga's decomposition method were used to analyze the impacts of age groups and causes of death on life expectancy. Results The life expectancy of these residents from 2016 to 2021 ranged from 83.68 to 84.40 years, which increased by 0.72 years in 2021 compared with that of 2016. The life expectancy of male residents was 81.47 to 82.15 years, demonstrating an increase of 0.68 years during the period. The life expectancy was 85.95 to 86.74 years for female residents, showing an increase of 0.79 years during the period. The decrease of mortality rate in 65 to 84 age group contributed 83.29% to the increase of the life expectancy (0.60 years) , while the decrease of mortality rate in 15 to 44 age group contributed -17.18% to the increase of the life expectancy (-0.12 years) . The largest contribution to the increase of life expectancy was the mortality reduction in cancer, followed by that in respiratory disease, which contributed 56.20% and 53.55%, respectively. The largest contribution to the decrease of life expectancy was increased mortality due to injuries and poisoning, followed by that due to endocrine, nutritional and metabolic diseases, which contributed -35.69% and -17.25%, respectively. Conclusion The life expectancy of residents in Jing'an District from 2016 to 2021 was 83.68 to 84.40 years, seeing an increase of 0.72 years. The increase of life expectancy was mainly attributed to the decrease of mortality in 65 to 84 age group and the decrease of mortality due to cancer. However, the increase of mortality due to injuries and poisoning had negative contribution.

In order to study the corrosion behavior of 316L and 2205 stainless steels and explore their application prospects in underwater production systems, the corrosion rate, electrochemical behavior and pitting corrosion resistance of 316L and 2205 stainless steels were analyzed and compared by using long period immersion test, cyclic polarization curve, potentiostatic polarization and electrochemical impedance spectroscopy (EIS) with the help of scanning electron microscope (SEM) and energy dispersive spectrometer (EDS). Results showed that the corrosion resistance of 2205 duplex stainless steel was better than that of 316L austenitic stainless steel in the simulated seawater environment with high CO2 content. Compared with 316L stainless steel, 2205 stainless steel had larger passive region, lower passive current density and larger passive film resistance. The high corrosion resistance of 2205 stainless steel was attributed to its higher pitting resistance equivalent (PREN) value and fewer inclusions, which enabled the passive film on the surface of 2205 stainless steel more stable and less prone to localized damage.

ObjectiveTo analyze the epidemiological characteristics of senile dementia death in Jing’an District from 2016 to 2020， as well as the trends of mortality， standardized mortality， years of life lost （YLL） due to early death， years lived with disability （YLD）， and disability-adjusted life year （DALY）， and to provide scientific basis for the prevention and control of senile dementia.MethodsThe distribution of senile dementia in terms of gender， age， marital status and education level was investigated in the senile dementia death cases from 2016 to 2020 in Jing’an District. The YLL， YLD， DALY and their rates of the residents of Jing’an District from 2016 to 2020 were calculated by using Global Burden of Disease （GBD 2019） research method and results in combination with the corresponding population data.ResultsCompared to those without dementia， deaths with dementia were more likely to be female， more likely to be over 80 years old， less likely to be married， and more likely to have education level under middle school. Among the deaths with dementia， only 27.70% of the primary cause of death was dementia， and the other main causes were cerebrovascular disease， coronary heart disease and diabetes mellitus， which accounted for 25.54%， 17.81% and 7.28%， respectively. There was a significant gender difference in the burden of disease on senile dementia in Jing’an District. Mortality， standardized mortality， YLL， YLD and DALY rates of females were higher than those of males. The burden of disease on senile dementia increased with age. The change trend of mortality and YLL rate from 2016 to 2020 was not statistically significant， while the YLD rate and DALY rate showed an upward trend， which was statistically significant.ConclusionAs the life span of residents in Jing’an District increases and the population aging deepens， the burden of disease on senile dementia is still heavy. This requires extensive attention of the whole society， and active exploration of prevention and control strategies and measures for senile dementia， so as to improve the life quality of patients and reduce the burden of disease.

A method for measuring (n,α) reaction cross sections of the gas sample induced by fast neutrons using a gridded ionization chamber (GIC) was established. There are several advantages using the GIC to measure gas samples. With this method, the (n,α) reaction cross sections of inert gases which are hard to exist as a solid can be measured. And the (n,α) reaction cross section for α particle emitting in all directions can be directly measured by using the gas sample. Furthermore, compared with using solid samples, using gas samples have far more nuclei in the measurement samples. Therefore, it is feasible to use neutron source with a better energy resolution to measure the resonance cross sections with gas sample. However, there are many problems to be solved when measuring (n,α) reaction cross section of gas sample by using the GIC. On the one hand, the nuclear reaction event will be affected by the wall effect, when the nuclear reaction is generated near the electrodes of the GIC or at the edge of the electric field. The wall effect will cause the measured event to locate outside the event area which cannot be counted. Not only is the number of nuclei of the gas samples involved in the (n,α) reaction difficult to determine, but the number of events, which are affected by the background or located below the threshold, is also difficult to count. On the other hand, the neutron fluence involved in the measurement of (n,α) reaction cross section of gas sample is difficult to measure. Aiming at solving the problems of the determination of the sample nuclei number, the measurement of neutron fluence, and the selection of events, which are all difficult for the gas sample, this method included three steps: First, simulation calculation was performed to select a suitable effective volume of the gas samples, so that the event is free of background and easy to be counted. Second, the neutron collimator and the timing information of cathode and anode signals were used to select and count the events generated in the effective volume of the gas sample. Third, combining the fission fragment measurement of the 238U(n,f) reaction and the simulation based on SuperMC, the neutron fluence through the effective volume was obtained. Measurements of relative cross sections of the 14N(n,α0) reaction using gas sample were performed at En=471, 487, 500, 512, 529, and 545 MeV. The results are in good agreement with those of ENDF/BⅧ.0 which verified the present measurement method.

Using wedge-splitting method, the changes of moisture content and double K fracture mechanical properties of three strength grades (C20, C30 and C40) concrete immersed in free water environment for 0 h, 2 h, 5 h, 24 h and 120 h were studied, so as to provide support for the safety evaluation of concrete structure in water environment. The results show that the higher the concrete strength grade is, the slower the water absorption rate is, the lower the moisture content is, and the longer soaking time it takes to reach saturation state. The initial cracking fracture toughness and unstable fracture toughness of concrete decrease linearly with the increase of moisture content. The initial cracking fracture toughness of C20, C30 and C40 concrete in saturated state is 29. 6%, 23. 2% and 33. 4% lower than that in dry state, and the unstable fracture toughness of C20, C30 and C40 concrete in saturated state is 22. 7%, 23. 9% and 33. 8% lower than that in dry state, respectively. Under the same moisture content, the initial cracking fracture toughness and unstable fracture toughness of C20, C30 and C40 concrete decrease similar basically. The P-CMOD curves obviously have a linear elastic non-crack initial stage, a stable expansion stage and an unstable expansion stage. With the increase of moisture content, the slope of linear elastic stage and stable expansion stage gradually decreases, and the curve of unstable expansion stage drops more and more gently. The critical crack opening displacement decreases gradually with the increase of moisture content, the deformation capacity and toughness of concrete decrease gradually. [ABSTRACT FROM AUTHOR]

Polyethylene (PE) agricultural mulch is prone to embrittlement and decomposition into microplastics (MPs) in the environment. More and more studies have shown that MPs can absorb organic pollutants, which may affect their distribution and bioavailability. Pesticides such as diflubenzuron are widely used in field vegetables, which have potential environmental and personal safety risks. They may coexist with MPs in the environment for a long time, resulting in pollution to the ecosystem. Therefore, it is helpful to explore the adsorption behavior of diflubenzuron and PE microplastics from agricultural plastic mulching film for the risk assessment of co-exposure of pesticides and microplastics. In this study, a batch adsorption experiment was carried out to systematically study the adsorption process of diflubenzuron and PE microplastics, and the environmental factors affecting the adsorption capacity of microplastics were evaluated, and the adsorption mechanism was discussed. The results showed that diflubenzuron could be adsorbed by PE MPs and reached the equilibrium adsorption capacity of 84.89 µg/g in 80 min. The dosage of 10 g/L PE MPs will be determined as the most effective dosage for the adsorption of insecticide. Under the initial concentration of 1.0 mg/L of insecticide, the adsorption capacity of insecticide increases first and then becomes stable with the increase of pH value in the range of 3~6. In the salinity range of 0.05%~3.5%, high salt concentration is not conducive to the adsorption of PE MPs for diflubenzuron. The pseudo-second-order model is more suitable to describe the kinetic process of PE MPs adsorption on diflubenzuron, which indicates that the adsorption process involves mass transfer and intra-particle diffusion in addition to the adsorption on the surface. It is necessary to investigate the adsorption processes between other pesticides and MPs and their influencing factors. [ABSTRACT FROM AUTHOR]

Objective: To establish the mass spectrometry database of Salmonella species by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry., Methods: By use of standard stains representing 21 species of Salmonella, a reference database was established MALDI-TOF-MS-based species identification. The profiles of colonies in the identical culture condition with different times were analysed for each of standard strains. To evaluate the database, 200 blind-coded isolates were tested by the established database and the original database., Results: The positive rate of identification by the original database, the established database and conbine-database were 87.5%, 97.0% and 97.5%. 21 Salmonella strains were divided into 3 types by MALDI-TOF-MS at distance level of 500. PCA of the reference strains showed difference between them. There were little changes of mass spectrometric data of several strains in different culture condition., Conclusion: The established database could expand the original one and be used for identification of Salmonella species. The strategy may be fit for other bacteria.

A model of fluid dynamics related to the myocardial bridginged and mural coronary artery was designed and manufactured according to the physical principle and characteristic of the mural coronary artery. The model can imitate systematically well the effect of myocardial bridging on hemodynamic change of the mural coronary artery under different controlled experimental parameter. The methodology is proved to be feasible and has good prosperity of experimental study.

Unlabelled: To study the effects of lead exposure on nitric oxide (NO), nitric oxide synthase (NOS), super oxide dismutase (SOD) and malondialdehyde (MDA) in cerebral cortex of rats, Wistar rats are exposed to lead from drinking 0, 18.4, 184 mg/L lead acetate solution respectively., Results: Cerebral cortex NOS activity in low and high-dosed lead exposure groups are significantly increased at the time of 7 days (P < 0.05), cerebral cortex NOS activity in low-dosed group is significantly decreased after 90 days and 30 days in high-dosed group (P < 0.05) as compared with that of the controls. Cerebral cortex NO content is markedly decreased in low-dosed group after 90 days poisoning and 14 days, 60 days, 90 days in high-dosed group (P < 0.05). SOD activity in low and high-dosed group is significantly decreased after 30 days exposure. MDA content is markedly increased after 14 days exposure in high-dosed group., Conclusion: It is suggested that the damage of cerebral cortex may caused by lead toxicity that results from the changes of NOS activity, NO level, SOD activity and MDA content in cerebral cortex.