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In order to effectively prevent and control the coal mine spontaneous combustion fire hazard, the research on the technology of cryogenic inert gas slurry was carried out aiming at the shortcomings of the existing inert gas fire-fighting technology, such as poor cooling effect and complicated conveying process. The experimental system for the preparation of cryogenic inert gas slurry and the cooling of heated loose coal was independently designed, and the temperature changes at different measuring points and the concentrations of CO and O2 in the experimental chamber were obtained under different injection flow rates. Results show that LCO2 (liquid CO2) is mixed with LN2(liquid nitrogen) in the pipeline transmission process, and injected into the experimental chamber in the form of solid, liquid and gas three-phase. The phase change occurs rapidly, the ordered structure is damaged, and a large amount of heat is absorbed. The temperature of air and coal in the box drops rapidly, and the fire prevention performance is better when large flow rate is injected. By comparing the fire-extinguishing effect of injecting liquid nitrogen and liquid carbon dioxide separately, it is concluded that the anti-fire-extinguishing technology of inert gas slurry has the advantages of both liquid nitrogen and liquid carbon dioxide, and the cooling and oxygen reduction effect is significant, and the anti-fire-extinguishing effect is better than that of liquid nitrogen and liquid carbon dioxide.

Magnetic anomaly is an important geophysical feature of coal field fires. In order to study the magnetic change law of high-temperature heated rocks and provide effective guidance for the application of magnetic method in the delineation of fire zones, the susceptibility measurement system was used to determine the magnetic susceptibility of Nalinmiao 3-1 coal roof sandstone. The effects of temperature, particle size, and magnetic field strength on the magnetic susceptibility of the samples were studied. The results show that the magnetic susceptibility of the burnt rock in the whole range of 25 ℃ to 600 ℃ increases with the increase of temperature, and decreases with the increase of the external magnetic induction intensity. When the heated temperature is less than 400 °C, the smaller the particle size of the sample, the greater the magnetic susceptibility; the effect of high temperature baking on the composition and structure of the rock is analyzed by X-ray diffraction experiments, indicating that during the high temperature baking of the rock, FeCO3 is oxidized into Fe3O4, which is the main reason why burnt rock is more magnetic than normal rock.

By comparing the change law of magnetic susceptibility of Ordos coal rock at normal temperature and during the temperature increase: as the temperature increases, the magnetic susceptibility also increases, and the composition of coal rock before and after heating is analyzed by X-ray diffractometer. It is found that the main reason for this change is that the ferromagnetic mineral composition of coal rock is changing during the heating process. This is used as the basis for the magnetic anomaly changes in the coalfield fire area. According to the theory of the gravitational potential field and magnetic potential field of the classic point, the coal bed fire area is used as a typical physical model to determine, and the Poisson formula method is used to determine the gravitational potential and magnetic potential. The second-order derivative of the cuboid gravitational potential is derived from the Poisson relationship, and the forward relationship of the magnetic anomaly of the coal field fire zone is obtained by integration. The magnetic anomaly characteristics of the coalfield fire zone model are calculated and simulated using Matlab. The results show that: as the depth increases, the extreme value of the magnetic field strength exhibited by the target body continues to decrease; the mutation rate of the intensity decreases continuously as it approaches the range of the anomaly; as the burial depth of the coalfield fire increases, the extent of magnetic anomalies has also continuously expanded to surrounding areas.

To improve the current situation of mine fire in China, and to optimize the deficiency of fire extinguishing technology of the single component inert gas, a dry ice preparation system and a visual test bench for CO2 phase transformation characteristics were set up. Based on different tube types experiments, the three-phase mixture were prepared, which were composed of liquid nitrogen and dry ice particles, the formation mechanism of three-phase was discussed and the phase transformation characteristics of CO2 was analyzed by numerical simulation. The result shows that as the included angle of CO2 pipeline increases, the desublimation temperature decreases from 168 K to 157 K, dry ice desublimation increases. Dry ice particles can be accumulated on the visual inner wall by gravity to form a coating, and its thickness showed a trend of extending to the upper part of the pipeline. The simulation result shows that as the angle between LN2 and CO2 branch pipe increases from 30° to 90°, the fluid flow rate increased from 14.5 m/s to 15.8 m/s, the temperature decrease-rating increased, and the volume fraction of dry ice at the bottom of the pipe increased, which was consistent with the experiment results.

Based on a torsional- transverse coupling model of a 2K- H spur planetary gear,the formula of vibration energy of the planetary gear transmission system is derived. The strain energy and kinetic energy of vibration of the planetary gear are calculated for four planetary gears under the operation condition,in which the ring gear is fixed. The distribution characteristic of vibration energy of the planetary gear is summarized. Without considering friction and damping of the planetary gear,the law of transmission of vibration energy of the planetary gear is obtained at the same and different orders of vibration.

The association between future time perspective and risk-taking behaviors has received extensive empirical attention. However, the underlying mechanisms that link future negative time perspective (FNTP) to risk-taking behaviors are complex and not well-understood. To address this gap, we adopted a longitudinal design that examined the association between FNTP and risk-taking behaviors, and the roles of coping styles and self-control in this association among 581 Chinese adolescents (age range = 12-18 years, 46.3% females). Results showed that FNTP at wave 1 was associated with risk-taking behavior at wave 3 via positive and negative coping styles at wave 2. Furthermore, adolescents with low self-control and more negative coping strategies preferred to engage in risk-taking behaviors as compared to their high self-control counterparts. Taken together, these research findings underscore the importance of considering the influence of the FNTP on adolescents' risk-taking behaviors and provide implications for developing preventions and interventions for reducing adolescents' risk-taking behaviors., Author(s): Kai Dou [sup.1] , Ming-Chen Zhang [sup.1] , Lin-Xin Wang [sup.1] [sup.3] , Yue Liang [sup.2] Author Affiliations: (1) https://ror.org/05ar8rn06, grid.411863.9, 0000 0001 0067 3588, Research Center of Adolescent [...]

Cyberbullying is a major youth social problem over the world and it has been associated with a variety of negative outcomes. However, few studies investigated how offline peer victimization affects cyberbullying and the potential relations between family factors and cyberbullying remains unknown. The current study addresses this gap in knowledge by examining the victimized by peers is associated with higher moral disengagement which further promotes college student's bullying online. A three-wave longitudinal study, each wave spanning six months apart, was conducted in a sample of 521 Chinese college students (M.sub.age = 21.91, SD = 1.18, 59.3% females). Results of moderated mediation model shown that peer victimization at Time 1 predicted more cyberbullying at Time 3 through moral disengagement at Time 2, after controlling for demographic variables and cyberbullying at Time 1. Time 2 moral disengagement significantly mediated the association between Time 1 peer victimization and Time 3 cyberbullying. In addition, high level of negative parenting strengthened the effect of moral disengagement at Time 2 on cyberbullying at Time 3. The prevention and intervention for both offline and online bullying victimization are discussed., Author(s): Ming-Chen Zhang [sup.1] , Lin-Xin Wang [sup.1] , Kai Dou [sup.1] , Yue Liang [sup.2] Author Affiliations: (1) grid.411863.9, 0000 0001 0067 3588, Research Center of Adolescent Psychology and [...]

Adaptation is an important issue in freshmen at the beginning of college life. Existing research on this topic has heavily relied on cross-sectional design and focused on the role of individual and family factors. Few studies have employed longitudinal design and focus on non-family contextual factors such as peers and teachers. This study aimed to explore the changes in academic, social, and personal-emotional adaptation throughout the first year of college and the associated individual (i.e., self-control, presence of life meaning, coping style, and allocentrism) and interpersonal (i.e., friendship quality and teacher-student relationship) correlates. Participants were Chinese freshmen recruited from two colleges in Southern China. They answered questionnaires on an online survey website at the second and eighth month after entering college (final N = 843). The results showed that academic adaptation did not change significantly over time, while social adaptation showed a significant decrease and personal-emotional adaptation showed a significant increase. Moreover, after controlling for respective baseline levels, each type of adaptation was predicted by a few factors. Noticeably, self-control positively predicted changes in all types of adaptation. In sum, the findings suggest that academic, social, and personal-emotional adaptation show different patterns of changes among Chinese college freshmen and that good self-control is a crucial factor that facilitates better college adaptation., Author(s): Jian-Bin Li [sup.1] [sup.2] , Ying-Shuang Wang [sup.3] , Yao Sun [sup.2] , Yue Liang [sup.4] , Kai Dou [sup.5] Author Affiliations: (1) grid.419993.f, 0000 0004 1799 6254, Department [...]

Panic buying is a globally witnessed behavior during the outbreak of COVID-19. This consumer behavior is related to many undesirable consequences, ranging from disrupting economic stability to hindering timely provision of supplies to those in dire need. As such, to understand the causes and underlying mechanisms of panic buying is crucial. Based on terror management theory, this study examined the contribution of perceived risk, social media use, and connection with close others to panic buying. Data were collected through an online survey from 972 Chinese citizens (65.9% female, M.sub.age = 33.69 years) at the beginning period of COVID-19 in early February 2020. The results found that individuals with a higher level of perceived risk were more prone to engage in panic buying, but this link was mitigated by connection with close others when individuals less used social media. Theoretically, this study advances the understandings of the psychological processes of panic buying during health crisis. Practically, alleviating individuals' perceived risk, establishing a healthy habit of social media use, and strengthening social ties are important to circumventing panic buying in times of COVID-19., Author(s): Jian-Bin Li [sup.1] , Rui Zhang [sup.2] [sup.3] , Lin-Xin Wang [sup.2] , Kai Dou [sup.2] Author Affiliations: (1) grid.419993.f, 0000 0004 1799 6254, Department of Early Childhood Education, [...]

Sickle cell disease (SCD) is a hereditary hemoglobinopathy characterized by painful vaso-occlusive crises (VOC) and chronic hemolysis. The mononuclear phagocyte system is pivotal to SCD pathophysiology, but the mechanisms governing monocyte/macrophage differentiation remain unknown. This study examined the influence of hemolysis on circulating monocyte trajectories in SCD. We discovered that hemolysis stimulated CSF-1 production, partly by endothelial cells via Nrf2, promoting classical monocyte (CMo) differentiation into blood patrolling monocytes (PMo) in SCD mice. However, hemolysis also upregulated CCL-2 through IFN-I, inducing CMo transmigration and differentiation into tissue monocyte-derived macrophages. Blocking CMo transmigration by anti-P selectin antibody in SCD mice increased circulating PMo, corroborating that CMo-to-tissue macrophage differentiation occurs at the expense of CMo-to-blood PMo differentiation. We observed a positive correlation between plasma CSF-1/CCL-2 ratios and blood PMo levels in patients with SCD, underscoring the clinical significance of these two opposing factors in monocyte differentiation. Combined treatment with CSF-1 and anti-P selectin antibody more effectively increased PMo numbers and reduced stasis compared with single-agent therapies in SCD mice. Altogether, these data indicate that monocyte fates are regulated by the balance between two heme pathways, Nrf2/CSF-1 and IFN-I/CCL-2, and suggest that the CSF-1/CCL-2 ratio may present a diagnostic and therapeutic target in SCD., Introduction Sickle cell disease (SCD) is characterized by hemolytic anemia and painful vaso-occlusive crises (VOC), caused by increased adherence of sickle RBCs to the underlying activated vascular endothelium (1, 2) [...]

Objective: Online aggression (OA) in Chinese university students is a public health concern. Drawing on the general aggression model (GAM), this study examines the extent to which nonviolent and violent stressful life events predict OA through altering moral cognition (i.e., moral disengagement). It also examines whether the two types of stressful life events interactively predict moral disengagement and whether violent stressful life events moderate the link between moral disengagement and OA. Method: Participants were 569 Chinese university students (Mage = 21.94 years, 42.5% males). They participated in a three-wave study, with 3-month spanning each wave, to self-report nonviolent stressful life events at Time 1 (T1), violent stressful life events and moral disengagement at T1 and Time 2 (T2), and OA at T1 and Time 3. Results: Results of path analysis showed that after controlling for the baseline levels of respective variables, T2 moral disengagement mediated the associations between T1 violent, but not nonviolent, stressful life events and Time 3 OA. The interactive effect between the two types of stressful life events at T1 on moral disengagement at T2 was insignificant; neither was the interactive effect between T2 moral disengagement and T2 violent stressful life events on Time 3 OA. The significance of results did not change after adjusting students' gender, age, and family socioeconomic status. Conclusion: These findings support the utility of GAM in explaining how OA develops in Chinese young people, implying that some situational inputs appear more important than others in these developmental processes. The results also shed light on strategies to prevent Chinese university students' OA. [ABSTRACT FROM AUTHOR]

This study used a quasi-experimental design to investigate the impact of Rapid Reading Skills Training (RRST) on some reading outcomes for primary school students in central China and also examined the influence of cognitive flexibility on intervention outcomes. A sample of 108 students (mean age = 11.75 years) were recruited. Students' cognitive flexibility was measured with the Wisconsin Card Sorting Task. Cluster randomization was used to assign students at the whole class level to either an experimental or control condition. A 12-session RRST intervention was completed with the experimental class (N = 54). Silent reading speed and passage comprehension were measured before and after training for all students. Independent samples t-tests and two-factor repeated measures ANOVA revealed that students in the experimental class displayed higher scores for reading speed and effective reading rate post-intervention than those in the control class. Students who had scored higher on cognitive flexibility showed significantly larger increases post-intervention than those scored lower. Results provide preliminary support for using RRST to increase rapid silent reading speed among Chinese primary school students, though replication and more rigorous experimental designs are needed. Cognitive flexibility may enhance gains associated with this type of intervention. Implications for school psychologists are discussed.