Dual-phase nano-glass-hydrides overcome the strength-ductility trade-off and magnetocaloric bottlenecks of rare earth based amorphous alloys.

Metal-hydrogen systems have attracted intense interest for diverse energy-related applications. However, metals usually reduce their ductility after hydrogenation. Here, we show that hydrogen can take the form of nano-sized ordered hydrides (NOH) homogeneously dispersed in a stable glassy shell, leading to remarkable enhancement in both strength and ductility. The yield strength is enhanced by 44% and the plastic strain is substantially improved from almost zero to over 70%, which is attributed to the created NOH and their interplay with the glassy shell. Moreover, the hydride-glass composite GdCoAlH possesses a giant magnetic entropy change (-ΔSM) of 18.7 J kg-1K-1 under a field change of 5 T, which is 105.5% larger than the hydrogen-free sample and is the largest value among amorphous alloys and related composites. The prominent ΔSM-ductility combination overcomes the bottlenecks of amorphous alloys as magnetic refrigerants. These results provide a promising strategy for property breakthrough of structural-functional alloys.

Beneficial effects of short-term exposure to indoor biophilic environments on psychophysiological health: Evidence from electrophysiological activity and salivary metabolomics.

BACKGROUND: The utilization of short-term natural exposure as a health intervention has great potential in the field of public health. However, previous studies have mostly focused on outdoor urban green spaces, with limited research on indoor biophilic environments, and the physiological regulatory mechanisms involved remain unclear. OBJECTIVES: To explore the affective and physiological impact of short-term exposure to indoor biophilic environments and their potential regulatory mechanisms. METHODS: A between-group design experiment was conducted, and the psychophysiological responses of participants to the indoor plants (Vicks Plant) were measured by a method combined the subjective survey, electrophysiological measurements, and salivary biochemical analysis. Volatile organic compounds (VOCs) from plants were also detected to analyze the main substances that caused olfactory stimuli. RESULTS: Compared with the non-biophilic environment, short-term exposure to the indoor biophilic environment was associated with psychological and physiological relaxation, including reduced negative emotions, improved positive emotions, lower heart rate, skin conductance level, salivary cortisol and pro-inflammatory cytokines, and increased alpha brainwave power. Salivary metabolomics analysis revealed that the differential metabolites observed between the groups exhibited enrichment in two metabolic pathways related to neural function and immune response: phenylalanine, tyrosine and tryptophan biosynthesis, and ubiquinone and other terpenoid-quinone biosynthesis. These changes may be associated with the combined visual and olfactory stimuli of the biophilic environment, in which D-limonene was the dominant substance in plant-derived VOCs. CONCLUSION: This research demonstrated the benefits of short-term exposure to indoor biophilic environments on psychophysiological health through evidence from both the nervous and endocrine systems.

Chinese young people's perceptions and preferences with regard to various edible urban plants. / 中国年轻人对各种可食用城市植物的看法和偏好.

The World Health Organization (WHO) defines health as "a state of complete physical, mental and social well-being and not merely the absence of disease or infirmity" (WHO, 2017), and mental health is defined as not only the absence of mental illness, but also the presence of psychological well-being. An expanding body of evidence highlights the relationship between nature (such as urban greenspace) and health (Li et al., 2019; Flaxman et al., 2020). However, human development and subsequent effects such as climate change and epidemic disease (COVID-19) lead to altered living environments and lifestyles. Expanding cities and urban residents have inequitable access to nature, particularly in areas of greater depriv­ation, where both public and private greenspaces are less available (Feng et al., 2021). In addition, young people spend more than 80% of their time indoors due to constant use of electronic devices for work, study, and entertainment (Klepeis et al., 2001). Mobile phones, personal computers, and video-game devices have become the main means for them to release stress. Excessive use of these electronic devices may affect normal brain activity, increasing the risk of Internet addiction and producing a range of physical and mental problems (Tran et al., 2017). These signal the pressing need for scientific investigation of efficient and convenient ways to increase contact with nature, or alternatively, to better regulate emotions indoors.

Polymeric fiber sensors for insertion forces and trajectory determination of cochlear implants in hearing preservation.

The level of hearing restoration in patients with severe to profound sensorineural hearing loss by means of cochlear implants (CIs) has drastically risen since the introduction of these neuroprosthetics. The proposed CI integrated with polymer optical fiber Bragg gratings (POFBGs) enables real-time evaluation of insertion forces and trajectory determination during implantation irrespective of the speed of insertion, as well as provides high signal quality, low stiffness levels, minimum induced stress even under forces of high magnitudes and exhibits significant reduction of the risk of fiber breakage inside the constricted cochlear geometry. As such, the proposed device opens new avenues towards atraumatic cochlear implantations and provides a direct route for the next generation of CIs with intraoperative insertion force assessment and path planning capacity crucial for surgical navigation. Hence, adaptation of this technology to clinical reality holds promising prospects for the hearing impaired.

Random forest assisted vector displacement sensor based on a multicore fiber.

We proposed a two-dimensional vector displacement sensor with the capability of distinguishing the direction and amplitude of the displacement simultaneously, with improved performance assisted by random forest, a powerful machine learning algorithm. The sensor was designed based on a seven-core multi-core fiber inscribed with Bragg gratings, with a displacement direction range of 0-360° and the amplitude range related to the length of the sensor body. The displacement information was obtained under a random circumstance, where the performances with theoretical model and random forest model were studied. With the theoretical model, the sensor performed well over a shorter linear range (from 0 to 9 mm). Whereas the sensor assisted with random forest algorithm exhibits better performance in two aspects, a wider measurement range (from 0 to 45 mm) and a reduced measurement error of displacement. Mean absolute errors of direction and amplitude reconstruction were decreased by 60% and 98%, respectively. The proposed displacement sensor shows the possibility of machine learning methods to be applied in point-based optical systems for multi-parameter sensing.

Residual organics removal from manganese electrochemical solution using combined Fenton oxidation process with adsorption over activated carbon.

The removal of residual organics from manganese (Mn) electrochemical solution using combined Fenton oxidation process with adsorption over activated carbon (AC) was investigated. The effect of operating conditions such as dosage of H2O2, H2O2/Fe2+ ratio, initial pH value, reaction temperature, and reaction time on Fenton oxidation was studied. Experimental results indicated that a maximum chemical oxygen demand (COD) of 83.2% was obtained under the optimized set of conditions: H2O2 concentration of 0.15 mol/L, H2O2/Fe2+ molar ratio of 3, initial pH value of 3, reaction temperature of 50 °C, and reaction time of 90 min. The leaching solution was furthered treated over AC and COD removal rate increased to 93.1% under 3.75 g/L dosage of AC, adsorption temperature of 70 °C, and adsorption time of 120 min. The adsorption mechanism of Mn over AC was detailly investigated, while the porous texture of AC was studied by nitrogen adsorption isotherm.

Two-dimensional vector accelerometer based on Bragg gratings inscribed in a multi-core fiber.

We propose and demonstrate a novel orientation-sensitive two-dimensional accelerometer based on fiber Bragg gratings inscribed in a multi-core fiber. Through monitoring of the wavelength shifts of three of the seven cores, including the central core and two outer cores which are not aligned in a straight line, information on vibration orientation as well as acceleration can be obtained simultaneously. Performance of the proposed accelerometer in terms of frequency, acceleration and vibration orientation are experimentally investigated. The designed two-dimensional accelerometer is capable of obtaining all these three parameters simultaneously. A sensitivity which is strongly dependent on the orientation is achieved, with a best orientation accuracy of 0.127° over a range of 0-180°. Moreover, the resonance frequency and the sensitivity can be optimized through adjusting the length and weight of the free-fiber. The ease of fabrication as well as the versatility of the proposed sensor makes it potentially useful in dynamic monitoring for industrial applications.

All-fiber polarization manipulation for high-order LP modes with mode profile maintenance.

We propose and experimentally demonstrate the polarization manipulation with mode profile maintenance for LP01, LP11a, and LP11b modes, with the help of elliptical-core few-mode fiber (e-FMF) based traditional polarization controller (PC) configuration. By manually adjusting the PC, we can successfully realize polarization conversion between horizontal and vertical linear polarizations, while individual mode profiles can be maintained without distortion. More than 30 dB of polarization extinction ratio (PER) can be achieved over the C-band, with little insertion loss of 0.2dB. The proposed all-fiber configuration is helpful to manage the polarization of high-order LP modes.