Advances in graphene reinforced metal matrix nanocomposites: Mechanisms, processing, modelling, properties and applications

Graphene has been extensively explored to enhance functional and mechanical properties of metal matrix nanocomposites for wide-range applications due to their superior mechanical, electrical and thermal properties. This article discusses recent advances of key mechanisms, synthesis, manufacture, modelling and applications of graphene metal matrix nanocomposites. The main strengthening mechanisms include load transfer, Orowan cycle, thermal mismatch, and refinement strengthening. Synthesis technologies are discussed including some conventional methods (such as liquid metallurgy, powder metallurgy, thermal spraying and deposition technology) and some advanced processing methods (such as molecular-level mixing and friction stir processing). Analytical modelling (including phenomenological models, semi-empirical models, homogenization models, and self-consistent model) and numerical simulations (including finite elements method, finite difference method, and boundary element method) have been discussed for understanding the interface bonding and performance characteristics between graphene and different metal matrices (Al, Cu, Mg, Ni). Key challenges in applying graphene as a reinforcing component for the metal matrix composites and the potential solutions as well as prospectives of future development and opportunities are highlighted

Quasi-static test study of tunnel with resistance-limiting shock absorption layer in high-intensity seismic

The Sichuan-Tibet Railway is faced with risks of active faults, unfavorable geological conditions, high in-situ stress levels, and a high potential for Traditional tunnel seismic measures that can no longer guarantee the safety of tunnel structures in high-intensity earthquake areas. The new shock absorption capacity layer with resistance-limiting is proposed in this paper and the resistance-limiting shock absorption principle. To study the safety of the new anti-shock lining structure, a large-scale quasi-static model test was carried out based on the improved static-dynamic coupling shear force. The test analyzes the response rules of strain, structural internal force, and lining failure form of tunnel lining, taking into consideration three influencing factors including layer layout position, layout density, and tunnel buried depth. The results showed that: 1) Under the action of low-cycle reciprocating shear strain, the failure mode of the shallow buried tunnel is mainly the tensile failure of the arch waist and the failure of the arch waist and the side wall, and the failure mode of the deeply buried tunnel is mainly the compression failure of the arch waist; 2) Compared with the case of no shock absorption layer, the lining tensile stress on the inner side of the arch waist position is significantly reduced. Under the high shear strain (0.20%), the increased tensile stress trend was slowed down on the inner side walls; 3) The main working area of the resistance-limiting layer can effectively improve the lining stress distribution underground vibration and protects the tensile damage on the arch waist to the side wall. The width and depth of the crack are weakened and the seismic bearing capacity of the width and depth of the crack is weakened and the seismic bearing capacity of the lining structure is greatly strengthened; 4) The lining cracks without the resistance limiting layer develop violently, and the crack at the arch waist runs The lining structure failure mode of the resistance limiting layer arranged at the arch waist is similar to The lining structure failure mode of the resistance limiting layer

Exploring the Impact of Passthrough on VR Exergaming in Public Environments: A Field Study

Sedentary behavior is becoming increasingly prevalent in daily work and study environments. VR exergaming has emerged as a promising solution in these places of work and study. However, private spaces in these environments are not easy, and engaging in VR exergaming in public settings presents its own set of challenges (e.g., safety, social acceptance, isolation, and privacy protection). The recent development of Passthrough functionality in VR headsets allows users to maintain awareness of their surroundings, enhancing safety and convenience. Despite its potential benefits, little is known about how Passthrough could affect user performance and experience and solve the challenges of playing VR exergames in real-world public environments. To our knowledge, this work is the first to conduct a field study in an underground passageway on a university campus to explore the use of Passthrough in a real-world public environment, with a disturbance-free closed room as a baseline. Results indicate that enabling Passthrough in a public environment improves performance without compromising presence. Moreover, Passthrough can increase social acceptance, especially among individuals with higher levels of self-consciousness. These findings highlight Passthrough's potential to encourage VR exergaming adoption in public environments, with promising implications for overall health and well-being

Exploring the Impact of Passthrough on VR Exergaming in Public Environments: A Field Study

Sedentary behavior is becoming increasingly prevalent in daily work and study environments. VR exergaming has emerged as a promising solution in these places of work and study. However, private spaces in these environments are not easy, and engaging in VR exergaming in public settings presents its own set of challenges (e.g., safety, social acceptance, isolation, and privacy protection). The recent development of Passthrough functionality in VR headsets allows users to maintain awareness of their surroundings, enhancing safety and convenience. Despite its potential benefits, little is known about how Passthrough could affect user performance and experience and solve the challenges of playing VR exergames in real-world public environments. To our knowledge, this work is the first to conduct a field study in an underground passageway on a university campus to explore the use of Passthrough in a real-world public environment, with a disturbance-free closed room as a baseline. Results indicate that enabling Passthrough in a public environment improves performance without compromising presence. Moreover, Passthrough can increase social acceptance, especially among individuals with higher levels of self-consciousness. These findings highlight Passthrough's potential to encourage VR exergaming adoption in public environments, with promising implications for overall health and well-being

Breaking the Isolation: Exploring the Impact of Passthrough in Shared Spaces on Player Performance and Experience in VR Exergames

VR exergames offer an engaging solution to combat sedentary behavior and promote physical activity. However, challenges emerge when playing these games in shared spaces, particularly due to the presence of bystanders. VR's passthrough functionality enables players to maintain awareness of their surrounding environment while immersed in VR gaming, rendering it a promising solution to improve users' awareness of the environment. This study investigates the passthrough's impact on player performance and experiences in shared spaces, involving an experiment with 24 participants that examines Space (Office vs. Corridor) and Passthrough Function (With vs. Without). Results reveal that Passthrough enhances game performance and environmental awareness while reducing immersion. Players prefer an open area to an enclosed room, whether with or without Passthrough, finding it more socially acceptable. Additionally, Passthrough appears to encourage participation among players with higher self-consciousness, potentially alleviating their concerns about being observed by bystanders. Our findings provide valuable insights for designing VR experiences in shared spaces, underscoring the potential of VR's passthrough to enhance user experiences and promote VR adoption in these environments

Effects of 60Co γ-ray and electron-beam irradiation on the color of dried chili products

This study was conducted to investigate the effects of 60Co γ-radiation and electron-beam irradiation on the color of dried chili products through comparative analysis of the color difference, non-enzymatic browning index, color value, and R/Y value. The experiment included different doses (0, 3, 7, and 16 kGy) and different storage times (0 and 30 d). The results revealed that when no storage time elapsed (0 d), the a* value decreased by 13% in the dried chili samples treated with a 60Co γ-ray dose of 16 kGy; the non-enzymatic browning value increased by 12%, and the R/Y value decreased by 16%. Moreover, the a*, b*, and L* values of the samples treated with electron beams at 7 kGy were significantly lower than those treated with 60Co γ-rays. Furthermore, increasing the dosage of either the 60Co γ-rays or electron beam resulted in large color differences and small non-enzymatic browning values for the chili powder samples stored for 0 d. Notably, at a dose of 16 kGy, ΔE* of the chili powder treated with 60Co γ-rays was higher than that of the powder subjected to electron-beam treatment. By contrast, the non-enzymatic browning value of the 60Co γ-ray-treated sample was significantly lower than that of the electron-beam-treated sample. After 30 d of storage, ΔE* of the chili powder samples treated with a 7 kGy dose of either 60Co γ-rays or electron beam was significantly higher than that recorded for the other dosage groups. Further, ΔE* was the highest for the samples treated with a 7 kGy dose of 60Co γ-rays. In conclusion, the impact of electron beams on the color of the dried chili products was less than that of the 60Co γ-rays. Furthermore, the effect of irradiation on the color of the chili powder was stronger than that on the color of the dried chilis

Outbreak of Acute Gastroenteritis Caused by Norovirus Genogroup II Attributed to Contaminated Cold Dishes on a Cruise Ship in Chongqing, China, 2017

In April 2017, several travelers with acute gastroenteritis on a cruise ship were reported. We conducted an investigation to identify the pathogen, mode of transmission, and risk factors. We searched and classified case-patient according to structured case definition, and collect date of the onset, clinical manifestations, and demographic information of cases. A case-control study was implemented to compare foods consumption between cases and asymptomatic travelers. Samples such as feces, rectal swab, vomitus, and environment swab were collected for testing. The attack rate was 18.2% (101/555), four cold dishes served on 11th, April were independently associated with an increased risk of disease: cold potherb (odds ratio (OR): 14.4; 95% confidence interval (CI): 2.2⁻93.3) and cold garlic sprout (OR: 26.1; 95% CI: 4.9⁻138.0) served at lunch, cold broad bean (OR: 5.8; 95% CI: 1.3⁻26.2), and cold cucumber (OR: 13.9; 95% CI: 2.3⁻84.2) served at dinner. A total of 15 samples were positive for norovirus genogroup II (GII) by using reverse transcription polymerase chain reaction (RT-PCR). This outbreak that occurred on the cruise ship was caused by norovirus GII. The evidence indicated that norovirus was mainly transmitted through consumption of cold dishes on 11th, April, which might be contaminated by asymptomatic cold dish cook

Real-world safety of ulinastatin: a post-marketing surveillance of 11,252 patients in China

Abstract Background The safety assessment of ulinastatin can guide clinical practice. The present study aimed to investigate the real-world safety of ulinastatin in China. Methods This multicenter study retrospectively analyzed the post-marketing surveillance data of consecutive patients treated with ulinastatin between August 2014 and June 2017 in the general wards and the intensive care units (ICU) of nine hospitals in China. Adverse drug reactions/adverse drug events (ADRs/ADEs) were collected and evaluated in a post-marketing database. Results A total of 11,252 consecutive patients were included in the study: 7009 ICU patients and 4243 general ward patients. Eleven patients with ADRs/ADEs were observed, including nine ICU patients and two general ward patients. The clinical manifestations were liver dysfunction (n = 5 ICU cases, n = 1 general case), thrombocytopenia (n = 2 ICU cases, n = 1 general case), leukopenia (n = 1 ICU case), and rash (n = 1 ICU case). During the study period, the drug ADR/ADE rate of ulinastatin injection was 0.98‰ (11/11,252 × 1000‰). Among the 11,252 valid patients, only 327 received ulinastatin in accordance with the drug specifications. After excluding unreasonable drug use, the calculated ADR rate was 3.06‰ (1/327 × 1000‰) (95% confidence interval: 0.0‰-17.1‰). In ICU and general ward patients, the use of other drugs combined with ulinastatin was associated with the occurrence of ADRs/ADEs (100% with ADRs/ADEs vs. 0% in controls, P < 0.001). Conclusions The incidence of ADRs/ADEs of ulinastatin is < 5‰. The ADRs/ADEs involved limited organs, mainly the skin, gastrointestinal tract, and blood. In most cases, the ADRs/ADEs gradually alleviated or recovered after drug withdrawal. The inappropriate/off-label use of ulinastatin should be the focus of surveillance

Management and control mode of underground coal mining based on medium and high-level intelligent technology

Coal is the guarantee energy in China, and its dominant position in energy will not change for a period of time in the future. Coal intelligent mining will show a rapid development trend and enter into a new stage of development. Through induction and analysis, the great significance, development law, contradiction, construction method and future development direction of intelligent construction of coal mine are summarized in this paper. This paper systematically expounds the reform process of coal mining technology and management mode in China, and summarizes the five stages of manual mining, ordinary mining, comprehensive mechanized mining, automatic mining, primary intelligent mining, as well as the corresponding technical modes. Breaking through the intelligent research ideas such as traditional coal roadheader mining, this paper puts forward 10 characteristics of medium and high-level intelligent mining technology of coal, namely, complete transparency of coal mine, comprehensive intelligence of perception, high-end intelligence of equipment, real-time reliability of network, integrated platform control, intelligent analysis of data, group collaboration intelligence, professional team employees, dynamic decision-making intelligence, disaster prevention and control matching, and gives the definition, characteristics, content and function of each characteristic. Based on the premise of medium and high-level intelligent technology, the corresponding ‘1+1’ management and control mode of coal mine mining is conceived, that is, one level is set in one coal mine, and a new flat platform management and control mode of ‘one command and control center+one professional team’ is constructed. Therefore, the mode can promote the reform of production mode, match the requirements of corresponding mining mode in the future intelligent rapid development and realize the real meaning of reducing personnel, increasing safety and improving efficiency. Finally, the further development of intelligent mining technology and mode in coal mine is prospected