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Diamond anvil cells have garnered significant attention in high‐pressure studies as a valuable tool for investigating material preparation, phase transition dynamics, and ultra‐high‐pressure physical chemistry. Its potential applications span fields such as materials science, condensed matter physics, chemistry, and geology. This study conducts a comprehensive review of the utilization of laser‐heated diamond anvil cell (LH‐DAC) devices in conjunction with in situ optical characterization techniques, such as X‐Ray and Raman scattering. Further, diverse in situ performance measurement methods encompassing electrical, thermal, magnetic, and acoustic analyses are examined. The development and role of the prevailing in situ measurement techniques have been described, along with the current progress in applied research for each technique. This study aims to facilitate the discovery of new structures and properties of materials under high pressure–temperature conditions. [ABSTRACT FROM AUTHOR]

Mn2(C2H6N6)4(NO3)4·2H2O (Mn) as one of the energetic coordination complexes was chosen for high‐pressure research. In this work, Mn was analyzed by in situ Raman scattering, infrared absorption, and synchrotron angle‐dispersive X‐ray diffraction (ADXRD) technologies up to ~20 GPa at room temperature. The vibrational modes of Mn at ambient pressure were comprehensively resolved based on the experimental results. Detailed spectral analyses revealed that Mn underwent three pressure‐induced phase transitions at 0.5, 2.5, and 5.7 GPa, respectively. ADXRD experiments confirmed the existence of these three phase transitions in Raman and infrared spectra analyses. Based on the analysis of the vibrational spectra and the changes of lattice parameters under pressure, it can be considered that the deformation of the 3‐hydrazino‐4‐amino‐1, 2, 4‐triazole (HATr) ligand led to the first phase transition, and the distortion of the triazole ring induced the second phase transition, and the rearrangement of the hydrogen bonds resulted in the third phase transition. In addition, it can be inferred from Raman spectra and ADXRD data that Mn may have experienced the abnormal expansion during the first phase transition. This work may lay the foundation for further investigating the structure and properties of energetic coordination complexes under pressure. [ABSTRACT FROM AUTHOR]

Benzyl azide was investigated byhigh-pressure Raman scatteringspectroscopy and X-ray diffraction technologies. A complete vibrationalanalysis of benzyl azide was performed by combining the experimentalmeasurements and theoretical calculations using DFT-based scaled quantumchemical approach. The high-pressure Raman spectra and calculationresults indicate that benzyl azide underwent a conformational changeat 0.67 GPa accompanied by rotation of methylene group and azide group.The frequency of the CH2bending mode decreases with increasingpressure due to the increase of the C–H···πinteractions, which is similar to the role of the hydrogen bond. Aliquid to solid phase transition occurred at 2.7 GPa, which was confirmedby the X-ray diffraction measurements. As the pressure reached 25.6GPa, all the azide group vibrations vanished, indicating that thedecomposition pressure of the molecular azide groups in organic azidesis lower than that of the azide ions in inorganic azides. [ABSTRACT FROM AUTHOR]

Dynamic computed tomography (CT) is usually employed to image motion objects, such as beating heart, coronary artery and cerebral perfusion, etc. Recently, to further improve the temporal resolution for aperiodic industrial process imaging, the swinging multi-source CT (SMCT) systems and the corresponding swinging multi-source prior image constrained compressed sensing (SM-PICCS) method were developed. Since the SM-PICCS uses the L 1 -norm of image gradient, the edge structures in the reconstructed images are blurred and motion artifacts are still present. Inspired by the advantages in terms of image edge preservation and fine structure recovering, the L 0 -norm of image gradient is incorporated into the prior image constrained compressed sensing, leading to an L 0 -PICCS Algorithm 1Table 1The parameters of L0-PICCS (δ 1 ,δ 2 ,λ1*,λ2*) for numerical simulation.Sourceswδ 1 (10-2)δ 2 (10-2)λ1*(10-2)λ2*(10-8)Noise-free510522.001.525522.001.55035002.00471014.33332.00500025522.00500050222.005000Noise51062002.505002554502.501.55054502.901.571027.385.91.5810000258.285.91.5850050522.001.5. The experimental results confirm that the L 0 -PICCS outperforms the SM-PICCS in both visual inspection and quantitative analysis.

Two-dimensional tin selenide (SnSe) nanosheets were synthesized using a plasma-assisted direct current arc discharge method. The structural characterization indicates that the nanosheets are single-crystalline with an average thickness of ~25 nm and a lateral dimension of 500 nm. The high pressure behaviors of the as-synthesized SnSe nanosheets were investigated by in situ high-pressure synchrotron angle-dispersive X-ray diffraction and Raman scattering up to ~30 GPa in diamond anvil cells at room temperature. A second-order isostructural continuous phase transition (Pnma → Cmcm) was observed at ~7 GPa, which is considerably lower than the transition pressure of bulk SnSe. The reduction of transition pressure is induced by the volumetric expansion with softening of the Poisson ratio and shear modulus. Moreover, the measured zero-pressure bulk modulus of the SnSe nanosheets coincides with bulk SnSe. This abnormal phenomenon is attributed to the unique intrinsic geometry in the nanosheets. The high-pressure bulk modulus is considerably higher than the theoretical value. The pressure-induced morphology change should be responsible for the improved bulk modulus.

Objective: To investigate the effect of Pseudomonas quinolone signal (PQS) on the virulence of Pseudomonas aeruginosa., Methods: Pseudomonas aeruginosa strain PAO1 was treated with PQS alone, PQS plus farnesol, or farnesol alone. The transcriptional levels of the regulator gene ExsA and virulence protein gene ExoS of type III secretion system were examined using quantitative real-time PCR, and spectrophotometry was employed to detect pyocyanin production in the bacteria. The adhesion and invasiveness of the treated PAO1 in cultured alveolar epithelial cells A549 were assessed on plate count agar, and their effects on the survival of a mouse model of peritonitis was compared., Results: The increase or decrease of PQS did not affect the growth of PAO1. Compared with the untreated bacteria, PQS-treated PAO1 showed obviously increased transcription levels of ExsA and ExoS (P<0.01) and pyocyanin production, which was significantly lowered by farnesol (P<0.01). In A549 cell cultures, farnesol-treated PAO1 exhibited significantly lowered adhesion and invasiveness, while PQS-treated PAO1 caused a significantly decreased survival time of mice with peritonitis (P<0.01). Farnesol treatment did not obviously affected ExsA transcription (P>0.05) but caused a significant reduction in the transcriptional level of Exos (P<0.05) in PAO1. PQS showed no significant effect on the adhesion and invasiveness of PAO1 (P<0.05)., Conclusion: PQS can maintain the adhesion and invasiveness of Pseudomonas aeruginosa, and in the hosts of the bacteria, PQS concentration is positively correlated with pyocyanin production and hence negatively with the survival time of the hosts.