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This study aims to evaluate the thermal performance of sodium alginate (SA) aerogel attached to nano SiO₂ and its radiative cooling effect on firefighting clothing without environmental pollution.

SA/SiO₂ aerogel with refractory heat insulation and enhanced radiative cooling performance was fabricated by freeze-drying method, which can be used in firefighting clothing. The microstructure, chemical composition, thermal stability, and thermal emissivity were analyzed using Fourier transform infrared spectroscopy, scanning electron microscopy, thermogravimetric analyzer and infrared emissivity measurement instrument. The radiative cooling effect of aerogel was studied using thermal infrared imager and thermocouple.

When the addition of SiO₂ is 25% of SA, the prepared aerogel has excellent heat insulation and a high radiative cooling effect. Under a clear sky, the temperature of SA/SiO₂ aerogel is 9.4°C lower than that of pure SA aerogel and 22.1°C lower than that of the simulated environment. In addition, aerogel has more exceptional heat insulation effect than other common fabrics in the heat insulation performance test.

SA/SiO₂ aerogel has passive radiative cooling function, which can efficaciously economize global energy, and it is paramount to environment-friendly cooling.

This method could pave the way for high-performance cooling materials designed for firefighting clothing to keep maintain the wearing comfort of firefighters.

SA/SiO₂ aerogel used in firefighting clothing can release heat to the low-temperature outer space in the form of thermal radiation to achieve its own cooling purpose, without additional energy supply.

This study aims to fabricate a novel electromagnetic interference (EMI) shielding composite aerogel with both thermal insulation and high temperature warning functions.

An emerging bio-based polypyrrole (PPy) gel/Fe₃O₄/calcium alginate (PFC) EMI shielding composite aerogel was prepared by freeze-drying and in situ polymerization method. First, Fe₃O₄/calcium alginate (CA) aerogel was obtained by freeze-drying the Fe₃O₄/CA mixture. Then, PPy/Fe₃O₄/CA was obtained by synthesizing PPy on the surface of CA/Fe₃O₄ aerogel through in situ polymerization. Finally, PPy/Fe₃O₄/CA was immersed in porphyrin solution (cross-linking agent) to get the final PFC EMI shielding composite aerogel.

Due to the matched impedance between Fe₃O₄ and PPy, the EMI shielding performance of PFC composite aerogel can reach up to −8 dB. In addition, the PFC EMI shielding composite aerogel also shows excellent self-extinguishing and thermal insulation properties. After leaving the flame, the burning PFC aerogel is quickly extinguished. When the PFC aerogel is placed on the heating plate at 230 °C, the temperature on the side of the aerogel away from the heating plate is only 90.3 °C after 5 min of heating. The electrical resistance of the PFC composite aerogel can be reduced from 3.62 × 104 O to 5 × 102 O to trigger the warning light after 3 s of exposure to the alcohol lamp flame. This reversible thermal resistance response characteristic can be used to give an early warning signal when the PFC encounters high temperature or flame.

This work provides a novel strategy for designing a multifunctional EMI shielding composite aerogel with repeatable high temperature warning performance. This PFC composite aerogel shows potential applications in the prevention of material combustion in high temperature electromagnetic environments.

This paper aims to investigate the dyeability of tussah silk fabric with lotus seedpod extract as the source of nontoxic and eco-friendly dyestuffs and functional agent.

Mordant free dyeing method was carried out using citric acid (CA) as the cross-linking agent to link the fibre and dye molecules. First, the natural pigment of oligomeric procyanidins was extracted from the lotus seedpod and then used to dye the tussah silk fabric. After the dyeing process, the dyed samples were treated with CA solution under different concentrations to improve the colour fastness.

The tussah silk fabric was successfully coloured in reddish brown through the dyeing process and charactered by using Fourier-transform infrared spectroscopy spectrometer. Moreover, lotus seedpod extract could impart excellent UV protection ability to the dyed samples, and UPF values reached up to 2000. CA dosage influenced the colour characteristics, UV protection and anti-wrinkling performance. The optimum dosage of CA was 7% (Wt.%). In addition, dyed silk fabric showed good antibacterial activity and the calculated bacteriostatic rate against Escherichia coli and Staphylococcus aureus were 83.27 and 60.2%, respectively.

This bio-dyeing strategy provided a simple and effective method for sustainable tussah silk fabric dyeing process.

This paper provides a novel dyeing strategy for mordant free dyeing and functionalization of tussah silk fabric, with lotus seedpod extract as natural pigment and CA as cross-linking agent to link the fibre and dye molecules.

This study aims to fabricate a multifunctional electromagnetic interference (EMI) shielding composite fabric with simultaneous high-efficiency photothermal conversion and Joule heating performances.

A multifunctional polypyrrole (PPy) hydrogel/multiwalled carbon nanotube (MWCNT)/cotton EMI shielding composite fabric (hereafter denoted as PHMC) was prepared by loading MWCNT onto tannin-treated cotton fabric, followed by in situ crosslinking-polymerization to synthesize three-dimensional (3D) conductive networked PPy hydrogel on the surface of MWCNT-coated cotton fabric.

Benefiting from the unique interconnected 3D networked conductive structure of PPy hydrogel, the obtained PHMC exhibited a high EMI-shielding effectiveness vale of 48 dB (the absorbing electromagnetic wave accounted for 84%) within a large frequency range (8.2–12.4 GHz). Moreover, the temperature of the laminated fabric reached 54°C within 900 s under 15 V, and it required more than 100 s to return to room temperature (28.7°C). When the light intensity was adjusted to 150 mW/cm², the PHMC temperature was about 38.2°C after lighting for 900 s, indicating high-efficiency electro-photothermal effect function.

This paper provides a novel strategy for designing a type of multifunctional EMI shielding composite fabric with great promise for wearable smart garments, EMI shielding and personal heating applications.

Most offender narrative being studied has been in oral forms, produced in the reciprocal process of researcher-(ex) offender interviews. This chapter offers an introduction to a variation of offender narrative study within the prison and rehabilitation context: the narrative of written autobiography. Since the early 1940s, Chinese reform institutions have required written autobiographies from new admitters, provided with clear presubscripted guidelines of instructions as well as postcensorship. For this chapter, we trace back and analyse this model based on 28 prisoners' autobiographies in mainland China between 2007 and 2009, as well as archive documents in different historical periods. We have found that the mandatory offender autobiographies are highly functional writings with clear requirements that embody the existing power structure. We have also found considerable commonality with findings in Western contexts on the presence and problems of narrative compliance in rehabilitation. We argue that narrative criminology should further engage in understanding the practice of narrative censorship and co-authorship in criminal justice processes, as it takes on different forms in different historical–social contexts.

Drawing on mood regulation theories, the purpose of this paper is to examine the impact of employees’ coworker-helping behaviors (OCB-Is) on the relationships between prior negative affect and subsequent job satisfaction and creative performance. The authors hypothesize that employees’ work competence is a moderator of the relation between negative affect and OCB-Is.

Data were collected by the experience sampling method of self-rating (twice per day) and coworker-rating (once per day) over two weeks by 120 administrative employees and their coworkers in a university; 743 available days were obtained.

Multilevel modeling showed that self-rated negative affect during the morning was associated with coworker-rated OCB-Is during the afternoon; OCB-Is were positively associated with self-rated job satisfaction and coworker-rated creative performance during the afternoon; based on an indirect effect, OCB-Is mediated the relationships between negative affect and job satisfaction, and negative affect and creative performance; and employees with high-level work competences tended to engage in OCB-Is more than employees with low-level work competences when experiencing negative affect.

These findings suggest that OCB-Is create a positive reaction by converting negative affect into positive job satisfaction and creative performance and that employees’ work competence is the boundary condition.

The purpose of this paper is to gain an understanding of the current research on Internet-plus.

The authors collected scholarly publications from the scientific databases Web of Science, Core Collection, Inspec and Compendex (Ei Village 2) and performed statistical analysis of the retrieved data from five perspectives.

The research on Internet-plus has obtained increasing attention in China. The top three research fields were social science, education and management.

The study will help researchers understand the current trends on Internet-plus.

In 1938, the Civil Aeronautics Board (CAB) was established to regulate the fare and route structures of the domestic airline industry. At that time, policy‐makers were fearful that free market conditions in the airline industry would not foster the growth which was deemed to be optimal in the public interest. After forty years of industry development, however, the market structure of the airline industry does not provide justification for regulation. Furthermore, the regulation itself has created problems which are undesirable to both the industry and the public. On October 25, 1978, President Carter signed into law a bill that will gradually remove the regulatory restrictions under which interstate domestic airlines have operated since 1938. All regulatory control over the airlines will end by 1982, and the CAB will be abolished in 1985.