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Beryllium is a lightweight metal that is toxic to humans. The critical health effects related to beryllium exposure are liver toxicity, immune system toxicity, and chronic beryllium disease (CBD). This study investigated the effects of occupational beryllium exposure on liver and lung function and hematologic parameters among beryllium smelter workers. A cross-sectional study was performed by comparing 65 exposed workers and 34 non-exposed workers. Health information was collected through questionnaire surveys and biochemical tests. The concentration of urinary beryllium was determined by Inductively Coupled Plasma Mass Spectrometry (ICP-MS). The findings indicated that the urinary beryllium levels of the exposed workers and the controls were 0.48 (0.115, 1.19) μg/mL and 0.0125 (0.005, 0.005) μg/mL, respectively (p < 0.001). Compared with the controls, the exposed workers showed a significant increase in serum alanine aminotransferase (ALT) level, hemoglobin (HGB) concentration, white blood cell (WBC) count, red blood cell (RBC) count, and systolic and diastolic blood pressure (SBP, DBP) (p < 0.05). Furthermore, the HGB concentration and ALT level were significantly correlated with the concentration of beryllium in urine (p < 0.05). The exposed workers had increased urinary concentrations of beryllium, in contrast to the control subjects. Moreover, the urinary beryllium levels among the exposed workers are much higher than that in the Chinese general population. Beryllium-exposed workers may be at risk of liver and hematologic impairments. [ABSTRACT FROM AUTHOR]

Electronic skin (e-skin) has been attracting great research interest and effort due to its potential applications in wearable health monitoring devices, smart prosthetics, humanoid robots and so on. Temperature is an important parameter for e-skin to perceive surroundings and people. However, little research has been carried out in the field of flexible temperature sensing and current temperature sensors still face many challenges in practical applications, such as high sensing performance, facile preparation, and differentiating from other stimuli. Herein, we develop a facile fabrication strategy for Ti3C2Tx based temperature sensors. As the sensing units, Ti3C2Tx nanoparticles and lamellae can be obtained simultaneously through controlling the fabrication conditions. These temperature sensors exhibit tunable sensing performances and a desirable combination of a high sensitivity (up to 986 °C−1) and a wide working range (140 °C). Due to their high sensitivity, these sensors can also be used as e-skin for proximity detection and illumination detection from ultraviolet to infrared light. For application demonstration, a 4 × 4 array of the sensors was fabricated for temperature mapping, indicating their great potential for monitoring approaching objects and temperature variations. [ABSTRACT FROM AUTHOR]

An environmentally benign hydrolysis of methylphenyldiethoxysilane (MePhSi(OEt)2) catalyzed by a rare earth superacid catalyst SO 2− 4 /TiO2/Ln3+ has been investigated. The hydrolysis rates decrease in the order SO 2− 4 /TiO2/Nd3+ > SO 2− 4 /TiO2/Y3+ > SO 2− 4 /TiO2/Sm3+ > SO 2− 4 /TiO2. The hydrolysis of MePhSi(OEt)2 is a first-order reaction with respect to the concentration of MePhSi(OEt)2, and the hydrolysis rate constant increases with increasing temperature. The activation energy E a and the pre-exponential factor for this hydrolysis catalyzed by SO 2− 4 /TiO2/Nd3+ have been determined as 322.50 kJ mol−1 and 7.12 × 1041 s−1, respectively. The products of the hydrolysis are oligomers of polymethylphenylsiloxane. The mechanism of MePhSi(OEt)2 hydrolysis is also discussed. GRAPHICAL ABSTRACT [ABSTRACT FROM AUTHOR]

A high sensitivity and large stretchability are desirable for strain sensors in wearable applications. However, these two performance indicators are contradictory, since the former requires a conspicuous structural change under a tiny strain, whereas the latter demands morphological integrity upon a large deformation. Developing strain sensors with both a high sensitivity (gauge factor (GF) > 100) and a broad strain range (>50%) is a considerable challenge. Herein, a unique Ti3C2Tx MXene nanoparticle–nanosheet hybrid network is constructed. The migration of nanoparticles leads to a large resistance variation while the wrapping of nanosheet bridges the detached nanoparticles to maintain the connectivity of the conductive pathways in a large strain region. The synergetic motion of nanoparticles and nanosheets endows the hybrid network with splendid electrical–mechanical performance, which is reflected in its high sensitivity (GF > 178.4) over the entire broad range (53%), the super low detection limit (0.025%), and a good cycling durability (over 5000 cycles). Such high performance endows the strain sensor with the capability for full‐range human motion detection. A strain sensor based on a Ti3C2Tx nanoparticle‐nanosheet hybrid network exhibits high sensitivity over the entire broad range due to the synergetic motion of nanoparticles and nanosheets and a constrained microcrack propagation mechanism. The migration of nanoparticles leads to a large resistance variation while the wrapping of the nanosheets bridges the nanoparticles and maintains the connectivity of the conductive pathways. [ABSTRACT FROM AUTHOR]