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BackgroundAlcohol dependence and related health problems have attracted greater than ever attention in recent years. Alcohol dependence not only affected personal behavior control ability， but also brought adverse effect to families and society.ObjectiveTo analyze the relationship between cognitive function and personality traits among male alcohol-dependent patients with aggressive behavior， in order to provide references for improving the cognitive function of male alcohol-dependent patients with aggressive behavior.MethodsMale patients with alcohol dependence attending Hunan Brain Hospital from March 2020 to March 2022 and fulfilling the International Classification of Diseases， tenth edition （ICD-10） diagnostic criteria were enrolled. According to the score of Modified Overt Aggression Scale （MOAS）， participants were classified into aggressive behavior group and non-aggressive behavior group at 1∶1 ratio， each with 80 cases. The enrolled subjects were then evaluated using Revised Eysenck Personality Questionnaire Short Scale for Chinese （EPQ-RSC） and Repeatable Battery for the Assessment of Neuropsychological Status （RBANS）. Pearson correlation analysis was utilized to examine the correlation between EPQ-RSC and RBANS scores among alcohol-dependent patients with aggressive behavior.ResultsScores on each subscale in RBANS were all lower in aggressive behavior group than those in non-aggressive behavior group （t=2.176， 2.580， 2.076， 2.308， 2.193， P

Traditional indicators such as equivalent salt deposit density, surface pollution layer conductance and leakage current are mainly used to measure the contamination grades of ceramic insulators, and the detection process is time-consuming and inefficient. Hyperspectral technology can obtain rich information of target spectrum non-contact, and has great application potential in insulator pollution detection. Therefore, a method of ceramic insulator pollution level detection based on hyperspectral technology is proposed in this paper. Firstly, there is a reflection phenomenon when collecting hyperspectral image due to the material of ceramic insulator, so histogram equalization is used to process the hyperspectral image to remove the reflective interference. Then, the hyperspectral image is preprocessed to remove the noise interference. And the successive projections algorithm (SPA) is used to extract the feature of the sample spectral line for removing the redundant information. Finally, the classification model of support vector machine (SVM) is established according to the characteristic spectral lines, and the classification accuracy of ceramic samples is 95%.

Due to the increasing speed of high-speed trains, the grounding system faces new challenges. When the relative motion between the train and the track occurs, the phenomenon of ground backflow will be intensified, resulting in the rise of train body potential, the abnormity or even damage of bearing and ground carbon brush, insulation joint, on-board sensors and other problems. In view of the existing problems of grounding reflux and train body potential of high-speed trains and the failure of twodimensional model of high-speed train grounding system to simulate and analyze the potential of the left and right sides of the same axle based on radial parameters, it is necessary to conduct a more perfect three-dimensional modeling of the integrated grounding system of high-speed trains. In order to suppress the grounding current and reduce the potential of the vehicle body, optimized analysis of the grounding mode and grounding parameters of the grounding system is conducted. In this paper, based on the measured data and theoretical analysis of the impedance and inductance parameters of the train body as well as the actual size parameters of the train body by the RCL tester, the three-dimensional circuit model of the integrated grounding system of the high-speed train is completed respectively from the aspects of traction transformer, overhead contact line, on-board transformer of high-speed train, high-voltage cable and train body under the premise of fully considering all the influencing factors. At the same time, combined with the dynamic grounding reflux test of the train passing under the on-line condition and the static overvoltage test of the high-speed train raising the pantograph and closing the VCB, the simulation results are compared with the measured results to verify the reliability of the three-dimensional model. Finally, based on the threedimensional simulation model, the radial parameters of the docking system and the three-dimensional distribution of the protection grounding and working grounding are optimized. After optimization, the ground current flowing through the protection grounding of the train is reduced to different degrees, and the distribution becomes more uniform. Meanwhile, the potential of the train body is maintained within the safety limit. [ABSTRACT FROM AUTHOR]

Anti‐icing of superhydrophobic materials has attracted a lot of attention. The potential for applications in power electronics, transportation, engineering and other fields is enormous. However, in practical applications, the anti‐icing performance parameters of superhydrophobic materials are still far from meeting the engineering requirements. It is a feasible solution to modify superhydrophobic materials to assist surface deicing by combining the vibration and heat generated by equipment in actual engineering. In this study, conventional superhydrophobic materials are modified by h‐BN. The electrical properties are improved to meet the engineering requirements. At the same time, it reduces the ice adhesion at the interface and improves the thermal conductivity of the material. The modified material has the possibility of assisting in de‐icing in engineering applications. A feasible solution is found for the engineering interface ice‐covering problem. [ABSTRACT FROM AUTHOR]

Plant communities may be co-invaded by invasive plants, sometimes even by congeneric invasive plants (CIPs). Despite the growing understanding of co-invasion in the environment, little is known about how CIP interactions and mechanisms regulate co-invasion. Darwin's naturalisation conundrum predicts that the coexistence of closely related species is difficult due to their structural and behavioural similarities. Nevertheless, communities containing closely related species are more susceptible to being invaded because close relatives may favour similar environments; therefore, this hypothesis should be followed in the co-invasion of CIPs. To explore whether the phylogenetic relatedness and origins of invasive species to CIPs can promote or hinder co-invasion, we conducted a controlled interaction and soil-legacy greenhouse experiment to quantify the growth response of invasive plants and their congeners. We consistently found that CIPs of identical origin were more likely to co-invade compared to CIPs of distinct origins. CIPs of distinct origins exhibited an antagonistic effect on co-invasion by allelopathy. Invasive plant-conditioned soil was more conducive to the growth of CIPs of identical origin than CIPs of distinct origins. Our results revealed the different effects of invader–invader phylogenetic relatedness on co-invader success and impact, suggesting the operation of different mechanisms across co-invasion. [ABSTRACT FROM AUTHOR]

In order to elucidate the reaction mechanism of ionic liquid-catalyzed CO2 with 2-aminobenzonitrile, [P4442]2[Hy] with two N− sites is designed for the efficient preparation of quinazoline-2,4(1H,3H)-diones. The results show that [Hy]2− can activate 2-aminobenzonitrile by hydrogen bonding with –NH2 in addition to activating CO2, and the key intermediate is revealed. [ABSTRACT FROM AUTHOR]

Because of the versatility of superhydrophobic materials, they have attracted a lot of attention even in power electronics, transportation, engineering, and other fields. The volume fraction of fluorinated silicon oxide nanoparticles in superhydrophobic materials is one of the most important factors. Increasing the volume fraction will decrease the stability between the coating and the hydrophobic surface. Especially, the flashover voltage of the coating gradually decreases from 10 to 35 vol.%. Meanwhile, the flashover voltage dispersion of the coating increases drastically after 30 vol.%. In order to improve the electrical properties of the superhydrophobic coating, self‐assembly of surface energy differences strategy is proposed in this work. A binary filling phase of the coating is introduced by 2D boron nitride nanosheets and silicon oxide nanoparticles. Although Hexagonal boron nitride with high surface energy and low roughness, it will be spontaneously assembled and wrapped by silicon oxide nanoparticle based on surface energy differences, which forming a low surface energy filled phase. Experiment results prove that the flashover voltage of the superhydrophobic coating is optimized by the binary filling phase coating. This method offers new ideas for the selection of filling phase and application of superhydrophobic materials. [ABSTRACT FROM AUTHOR]

The grounding electrode line is an important part of the Ultra high voltage direct current (UHVDC) transmission system. It acts as the channel to conduct the unbalanced current and the grounding current.The arcing horn consists of a pair of electrodes installed in parallel at both ends of the insulator string, which provides a discharge channel for the fault current by an air gap to protect the insulators. In this paper, the voltage and current distributions of the arcing horn were studied when the grounding electrode line was struck by lightning. It is found that the current and voltage gradually decrease along the direction from the converter station to the earth electrode. An active arc extinguishing method based on variable resistance for arcing horn was proposed. An electromagnetic transient simulation model of the grounding electrode line is established based on the electrical parameters of a ±800 kV UHVDC transmission system. It is found that the absorbed energy of the arc extinguishing unit needs to be at least 31.2 and 49.6 kJ when the lightning current is 20 and 50kA, respectively. According to the calculation results, the arcing horn with arc extinguishing unit was developed and tested. The test results verifies that the designed arcing horn can meet the requirements of engineering application. [ABSTRACT FROM AUTHOR]

Zinc indium sulfide (ZnIn2S4), as a significant visible-light-responsive photocatalyst, has become a research hotspot to tackle energy demand and environmental issues owing to its excellent properties of high stability, easy fabrication, and remarkable catalytic activity. However, its drawbacks, including low utilization of solar light and fast photoinduced charge carriers, limit its applications. Promoting the response for near-infrared (NIR) light (~52% solar light) of ZnIn2S4-based photocatalysts is the primary challenge to overcome. In this review, various modulation strategies of ZnIn2S4 have been described, which include hybrid with narrow optical gap materials, bandgap engineering, up-conversion materials, and surface plasmon materials for enhanced NIR photocatalytic performance in the applications of hydrogen evolution, pollutants purification, and CO2 reduction. In addition, the synthesis methods and mechanisms of NIR light-driven ZnIn2S4-based photocatalysts are summarized. Finally, this review presents perspectives for future development of efficient NIR photon conversion of ZnIn2S4-based photocatalysts. [ABSTRACT FROM AUTHOR]

Objectives: As genetic testing is increasingly used in non-medical fields, the judgment of people's potential conditions based on predictive genetic information inevitably causes genetic discrimination (henceforth GD). This article aimed to systematically investigate the disparity in attitudes and worrying scenarios concerning GD in China. Methods: A questionnaire survey of 555 respondents was conducted. Statistical tests were used to examine disparity in attitudes between gender, age, and education. A descriptive analysis was also conducted to explore other worrying scenarios. Results: It shows that (1) men are more tolerant of GD compared to women, and (2) participants aged between 18 and 30 years old possess the highest objection to GD. However, (3) no indication can attest to the relationship between educational level and perspective on GD. In addition, (4) the acceptance of gene testing in the three most common scenarios is ranked in descending order as follows: partner choice, insurance services, and recruitment. Moreover, (5) worrying scenarios relating to GD include: education, social occasions, medical services, fertility, shopping, and so on. Conclusions: Based on the results, suggestions proposed include developing a blacklist mechanism in the field of genetic data application and strengthening the security regulations for the commercial use of genetic data. [ABSTRACT FROM AUTHOR]

Corona discharge is one of the key factors that lead to the hydrophobicity loss of silicone rubber insulators used on the roof of high-speed trains. Based on the artificial experimental wind-tunnel platform, influences of AC corona intensity and airflow velocity on the hydrophobicity distribution of the silicone rubber surface were studied. According to the corona discharge phenomena and measured discharge current, influences of airflow velocity and voltage on the characteristics of corona discharge in a high-speed airflow environment were discussed. Results reveal that the hydrophobicity distribution on the silicone rubber surface shifts along the airflow direction in the high-speed airflow environment when the voltage is relatively high. When ionization zone develops to the needle-plate gap, the discharge path is deflected to the direction of airflow, which is responsible for the change of the hydrophobicity distribution. It is notable that the deflection distance decreases with the increase of airflow velocity. This is attributed to the fact that the electrons with variable horizontal distance from the electron to the plate electrode center are subjected to different electric field forces, resulting in different influences of high-speed airflow on them. These results are of engineering and theoretical significance for insulators used in high-speed railways. [ABSTRACT FROM AUTHOR]

In this paper, a surface discharge test was conducted on a silicone rubber insulating sheet, an epoxy resin insulating sheet, a porcelain insulating sheet, and a glass insulating sheet by using an independently constructed test platform of insulating media to study the discharge characteristics along the surface of insulating media under low air pressure and strong airflow environment. Experiments were conducted to obtain the variation in the discharge characteristics along the surface of the four kinds of insulation media with respect to airflow velocity at different air pressures. The discharge voltage characteristics and discharge morphology characteristics along the surface of the insulating media in a strong airflow environment at low air pressure are elucidated. This paper provides theoretical support for the selection of insulation materials and insulation protection design for a low air pressure and strong airflow environment. [ABSTRACT FROM AUTHOR]

The gas–solid interface of high-voltage insulating equipment is a weaker part of insulating equipment insulation, and preventing the occurrence of discharge along the surface of insulating equipment is a critical problem for high-voltage insulation. This article investigates the discharge characteristics and charge movement characteristics of insulating media under an airflow environment. The surface discharge characteristics of the insulating medium in the airflow environment were obtained by using a high-velocity airflow test platform, and the surface discharge voltage characteristics, discharge path characteristics, and force conditions of the discharge process were analyzed. The surface charge motion characteristics of the insulating medium in the high-velocity airflow environment were also tested, and the distribution characteristics, dissipation characteristics and conduction mechanism of the surface charge of the insulating medium in the high-velocity airflow environment were revealed. The research results showed that: the discharge voltage along the insulating medium surface gradually increases with the increasing velocity of airflow; the discharge path along the surface of the insulating medium gradually shifts backward under the action of airflow; under the action of airflow, the charge on the insulating medium surface is blown away, thus reducing the charge concentration on the insulating medium surface; the trap level center of the insulating medium gradually decreases under the action of airflow, which provides the conditions for the charge blowing effect on the insulating medium surface. This investigation supplies the theory support for the protection of insulation equipment in an airflow environment and technical guidance for the insulation design of insulating equipment in an airflow environment to ensure the secure and steady running of insulating equipment in high-speed trains and high-voltage transmission lines. [ABSTRACT FROM AUTHOR]

Knowing more about insulator pollution is of guiding significance to the development of anti-pollution strategies. Traditional methods can be used to determine only the pollution degree of insulators. However, the pollution distribution also has a substantial influence on the flashover voltage of insulators even under the same equivalent salt deposit densities (ESDD). In this article, an ESDD spectral density method and a visualization method based on hyperspectral technology are proposed. The proposed method presents the ESDD distribution using hyperspectral images. A detection model based on characteristic wavelengths is established with partial least squares regression to detect the insulator ESDDs. Based on the ESDD detection results, the features of the ESDD spectral density process, including the building of the ESDD probability graph, the overall ESDD, and visualization of the ESDD, are presented. Example analyses of field-operating insulators were conducted, revealing that the ESDD spectral density can be used to track the pollution distribution of insulators and that the pollution degree can be calculated from the overall ESDD. The error of the overall ESDD calculated by this method is within 10%. In addition, visualization of the pollution distribution can more intuitively record the degree of pollution and the nonuniform distribution characteristics. Both the pollution degree and distribution can be obtained by this method. Therefore, hyperspectral technology can overcome the limitations of traditional methods and convert the ESDD results into an image to determine the ESDD distribution. These research results provide theoretical instruction for guiding insulation design and anti-pollution strategies for operating transmission lines. [ABSTRACT FROM AUTHOR]

Highlights • Polyamidoamine generation 1.0 triggers aggregation of gold nanoparticles. • Fatty acids disassemble the polyamidoamine/nanoparticle aggregates. • The aggregation/disassembling process is reflected by changes in UV–Vis spectra. • The spectroscopy is employed in determining total free fatty acids in edible oils. Abstract We synthesized polyamidoamine (PAMAM) dendrimers and citrate-capped gold nanoparticles (AuNPs), and explored the applicability of the PAMAM/AuNP assay in determining total free fatty acid (FFA) contents in edible oils based on a competitive colorimetry, in which the PAMAM-triggered AuNP aggregation was suppressed by FFAs. The generation and concentration of PAMAMs, the chain lengths of FFAs as well as the concentration and pH of the background electrolytes of the assay were optimized. The average acid values of the sunflower seed, corn and extra virgin olive oils determined by PAMAM/AuNP assay were 1.31 ± 0.07, 0.33 ± 0.02 and 1.49 ± 0.07, respectively, which were not significantly different from the corresponding 1.27 ± 0.08, 0.32 ± 0.01 and 1.61 ± 0.06 by the standard nonaqueous titration. Our results suggest that the method is promising in detecting FFAs in edible oils, and implementation of the method expands the technological scope for FFA analysis. [ABSTRACT FROM AUTHOR]

Under natural environment, the washing effect of rainfall has great influence on the cleaning of outdoor insulators. To study the law of natural contamination on the insulator surface in the rainy weather. The natural contamination experimental study has been carried out for four 500 kV transmission lines in hundreds of sites and stations in Hunan Province for five years. The equivalent salt deposit density (ESDD) and non‐soluble deposit density (NSDD) were measured monthly, and the meteorological data were statistically analysed. The results show that the residual ESDD and NSDD on the surface of insulators were affected by the rainfall intensity, duration and flushing angle. Meanwhile, based on the measured data of ESDD and NSDD, a cleaning model of insulators was established. The effects of splash on the bottom surface of insulators were studied by using the raindrop kinetic energy and Gaussian probability statistical distribution. [ABSTRACT FROM AUTHOR]

The surface pollution layer of polluted insulator absorbs fog water and gets damp in salt fog. Meanwhile, the salts in the salt fog deposit on insulator surface, which increases the surface conductivity and degrades the flashover performance of insulators. At present, the effects of fog water conductivity (γ20) and equivalent salt deposit density (ESDD) are analysed separately, which does not reveal the essence of the flashover in salt fog. In this study, a plenty of experiments on porcelain, glass and composite insulators are carried out in salt fog conditions, and the 50% flashover voltage stress, leakage current and variation of ESDD during the wetting process are studied. The concept of additional salt deposit density (ASDD) is proposed to quantitatively analyse the additional ESDD caused by salt fog. The test results indicate that the ac flashover voltage stress decreases with the increase of both ESDD and fog‐water conductivity. Both the ESDD and leakage current become larger in salt fog compared with those in clean fog. The ASDD can be applied to analyse the combined effect of ESDD and fog‐water conductivity and be expressed as ASDD = k × γ20 × ESDD. Then the flashover voltage stress is E = A × (ESDD + ASDD)−a. The values of k for the porcelain, glass and composite insulators are 0.179, 0.191 and 0.230, respectively. The flashover in salt fog environment is a special kind of pollution flashover in essence. [ABSTRACT FROM AUTHOR]

The occurrence of large‐scale haze–fog weather in some developing countries brings a new threat to the safe operation of outdoor insulation. In order to study the effect of the haze–fog on the flashover performance of insulators and the flashover mechanism, kieselguhr, calcium sulphate (CaSO-4) and ammonium sulphate ((NH4)2SO4) in different particle sizes were mixed with ultrasonic fog to simulate the haze–fog environment and quantitative ac flashover experiments on the standard suspension porcelain insulator were carried out. The test results indicate that the flashover voltage is related with the pollution degree, particle component, particle size and fog‐water conductivity, and may decrease by more than 20% under haze–fog environment. The effect of salt aerosols on flashover voltage is determined by the solubility and larger than that of non‐soluble mineral aerosols or organic carbon aerosols. The flashover voltage increases with the increase of the particle size, but decreases with the increase of fog‐water conductivity. The flashover of insulator under haze–fog condition is a special kind of pollution flashover in essence. [ABSTRACT FROM AUTHOR]