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Nails with different diameters are inserted to different depths to induce internal short circuits in the battery, resulting in a large amount of smoke and even flames.

The safety problems of lithium-ion batteries, such as fire and explosion, have become the main issues constraining the rapid development of electrochemical energy storage. This paper proposes a new method to obtain the internal pressure and gas components of battery under adiabatic condition. Subsequently, the internal pressure evolution of a fully charged 300 Ah LiFePO4(LFP) cell during thermal runaway (TR) are analyzed. At the temperature of safety venting (SV), the internal peak pressure recorded is 412 kPa and the gas release of H2and CO are 35.2 % and 23.7 %, respectively. Basing on the analysis, the gas release temperature calculated by internal pressure is about 5 K lower than self-generated heat temperature. Before SV, the electrolyte volatilization and gas releasing are decoupled, and the gas release is about 0.009 mol. The internal pressure evolution of battery can be divided into three stages. At stage C, the gas release which cause SV account for 43.97 % of the gas volume and the reactions releasing H2and CO gas are the prime chemical reason for SV. These results are of great significance to the setting of early warning system and the emergency response to TR.

The coherent random laser (CRL) from dye-doped polydimethylsiloxane (PDMS) has been investigated in both nanoparticle-doped (NP-doped) thin films and pure dye thin films. Compared with the literature, the pump threshold is only 1.5 mJ/cm2in the pure dye thin film with a low dye concentration. The spontaneously formed micro-/nanocrystals of Pyrromethene 597 (PM597) dye support both gain and random feedback in the bulk of the PDMS during the sample preparation. When the SiO2NPs were doped, the pump threshold was reduced to 0.75 mJ/cm2. The threshold increased after the film was peeled off from glass, which indicates that the photon localization effect of the leaky-waveguide structure plays an important role in the reduction of the CRL threshold. By a change in the pump stripe length or the thickness of the film, the peak wavelength red-shifts 6.7 or 5.93 nm, respectively. The PM597 dye molecule solubility changes, and they spontaneously aggregate in the process of toluene volatilization; the PDMS cures, which is the reason for the formation of PM597 micro-/nanocrystals. This thin film random laser with a low dye concentration can be used in integrated optoelectronics and display imaging.

ABSTRACTLung cancer is the leading cause of cancer-related death worldwide. Bromodomain and extraterminal domain (BET) proteins act as epigenome readers for gene transcriptional regulation. Among BET family members, BRD4 was well studied, but for its mechanism in non-small cell lung carcinoma has not been elucidated. eIF4E regulates gene translation and has been proved to play an important role in the progression of lung cancer. In this study, we first confirmed that BET inhibitors JQ1 and I-BET151 suppressed the growth of NSCLCs, in parallel with downregulated eIF4E expression. Then we found that knockdown of BRD4 expression using siRNAs inhibited the growth of NSCLCs as well as decreased eIF4E protein levels. Moreover, overexpression of eIF4E partially abrogated the growth inhibitory effect of JQ1, while knockdown of eIF4E enhanced the inhibitory effect of JQ1. Furthermore, JQ1 treatment or knockdown of BRD4 expression decreased eIF4E mRNA levels and inhibited its promoter activity by luciferase reporter assay. JQ1 treatment significantly decreased the binding of eIF4E promoter with BRD4. Finally, JQ1 inhibited the growth of H460 tumors in parallel with downregulated eIF4E mRNA and protein levels in a xenograft mouse model. These findings suggest that inhibition of BET by JQ1, I-BET151, or BRD4 silencing suppresses the growth of non-small cell lung carcinoma through decreasing eIF4E transcription and subsequent mRNA and protein expression. Considering that BET regulates gene transcription epigenetically, our findings not only reveal a new mechanism of BET-regulated eIF4E in lung cancer, but also indicate a novel strategy by co-targeting eIF4E for enhancing BET-targeted cancer therapy.

The random laser from sheared dye-doped polymer-dispersed liquid crystal (DDPDLC) is investigated. As the emission intensity weakens, the threshold of random laser from DDPDLC increases from 2.0 mJ/pulse to 4.0 mJ/pulse, and the degree of polarization (DOP) increases from 0.1 to 0.78, obviously when the shear distance increases from 0 mm to 4 mm. As the liquid crystal droplets are gradually oriented in the shear direction caused by alignment direction of polymer chain and anisotropy of droplet shape, the scattering intensity perpendicular to the shear direction gradually decreases and that parallel to the shear direction gradually increases. The anisotropic absorption of the laser dye also plays a certain role as the shear distance is 0 mm. The controllable intensity and polarization degree of random laser have a huge potential for sensing applications.

With the large-scale application of LiFePO4(LFP) batteries in the field of electrochemical energy storage (EES), more attention is being paid to the problem of thermal runaway (TR). This paper investigates the TR and gas venting behaviors of 86 Ah LFP batteries caused by overcharging and overheating. Compared with previous studies, the main contributions lie in the gas venting behavior analysis of the LFP batteries during the whole TR process and the causes of the safety venting under overcharging and overheating. Two significant results are obtained from the experiments: (I) the overcharging of the LFP battery promotes gas release inside the battery, resulting in advance of safety venting, but the safety venting under overheating is caused by electrolyte volatilization; (II) the total gas volume (including H2, CH4, C2H4, CO and CO2) during TR under overcharging and overheating is 62.1 and 101.3 L. Moreover, the results calculated by the fractional compelling dose model show that there is no toxicity before TR under overheating. However, the duration of toxicity under the overcharge is 1211 s before TR. This work provides a meaningful theoretical guide for EES systems' safety warning and fire protection.