An accurate in situ electrical resistivity measurement of cuprous oxide cubes has been conducted in a diamond anvil cell at room temperature with pressures up to 25 GPa. The abnormal electrical resistivity variation found at 0.7-2.2 GPa is attributed to the phase transformation from a cubic to a tetragonal structure. Three other discontinuous changes in the electrical resistivity are observed around 8.5, 10.3, and 21.6 GPa, corresponding to the phase transitions from tetragonal to pseudocubic to hexagonal to another hexagonal phase, respectively. The first-principles calculations illustrate that the electrical resistivity decrease of the tetragonal phase is not related to band-gap shrinkage but related to a higher quantity of electrons excited from strain-induced states increasing in band gap with increasing pressure. The results indicate that the Cu(2)O cubes begin to crush at about 15 GPa and completely transform into nanocrystalline at 25 GPa.

Objective Prepregnancy obesity is an epidemic disorder that seriously threatens both maternal and offspring health. This study investigated the effects of β3‐adrenergic receptor (β3‐AR) activation on the perinatal outcomes in a diet‐induced prepregnancy obese (PPO) murine model. Methods Four‐week‐old female C57BL/6 mice were fed high‐fat diet or chow diet for 16 weeks to yield PPO mice and chow‐fed (CF) lean mice, respectively. After successful mating with CF males, the PPO and CF mice were both randomly divided into vehicle control‐ or CL316,243 (a highly selective β3‐AR agonist)‐treated groups. On gestational day 7, subcutaneous infusion of CL316,243 or saline vehicle (1 mg/kg/d) was provided using osmotic pumps. The perinatal outcomes, adipose tissue morphology, and metabolic and inflammatory markers were examined. Results Chronic β3‐AR agonist infusion induced brown adipose tissue activation and white adipose tissue browning and countered obesity‐induced alterations in lipid profiles, insulin resistance, and systemic and local inflammatory states. Moreover, β3‐AR activation was associated with improved placental perfusion and offspring outcomes. Conclusions Our results provide proof‐of‐principle evidence that pharmacological β3‐AR activation may be of therapeutic potential in preventing prepregnancy‐obesity‐associated adverse maternal and offspring perinatal outcomes.

The non-contact mechanical seal end faces opening friction condition detection and the measurement of film thickness when the end faces is just-lift-off, which are always key problems for scholars engaged in sealing industry for many years, but there is no effective solution. Acoustic emission (AE) signal generated in the running process of mechanical seal end faces has a plenty of information about the faces contact state. According to this, the thickness measurement of mechanical seal and opening condition monitoring technology by using particle filter are put forward based on the acoustic emission signal. Acoustic emission sensor is installed in the stationary ring seat, used for the indirect outer detection of the dynamic and stationary rings opening condition. The acoustic emission signals are processed by particle filter technology, and then the signal features are extracted in time domain, frequency domain and wavelet packet energy. A BP neural network model is established, the features of signal characteristic used as input of the model. It is finally realized that the mechanical seal end faces opening condition was recognized and the film thickness was measured. Eddy current sensor is installed inside the stationary ring and used for direct measurement of film thickness and verify the results got from the BP neural network. Through the experiment, this method is practical and effective, and which can be used in the monitoring of mechanical seal end faces working condition in industrial field.

A method for measuring the thickness of liquid-lubricated film of end face and detecting the friction of end face of mechanical seals has been presented in this article. Eddy current sensors installed on the inner ring embedded in the stationary ring of mechanical seals are used to measure the thickness of the liquid-lubricated film. Acoustic emission sensor placed on the stationary ring base is used to detect the friction of end face. The micro scope condition monitoring of end face is of importance to ensure mechanical seals run normally. With a set of tests, the results demonstrate that the method is effective.

This paper was reported a polymeric support metal catalyst and its application in oxidation of ethylbenzene with molecular oxygen. The Poly(1-vinylimidazole-co-methyl methacrylate) copolymer (PVM) was directly mixed with copper sulfate solution to prepare the catalyst of Cu(II)-PVM. The appropriate reaction temperature and amount of catalyst were 130°C and 0.2g. Recycling studies indicated that the catalyst could be recycled at least four times without significant decrease of catalytic activity.