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Background The aim of this study is to add to the current knowledge regarding extracranial malignant rhabdoid tumor (MRT), a rare and highly aggressive tumor that occurs most commonly in infants and young children. Patients and Methods A retrospective medical record review was conducted on 53 patients with pathologically confirmed MRT in Beijing Children's Hospital between January 2007 and October 2017. Results Fifty‐three patients were diagnosed with MRT at a median age of 16 months, including 32 cases of malignant rhabdoid tumor of the kidney (MRTK) and 21 cases of extrarenal extracranial rhabdoid tumor (EERT). Fourteen (14/32, 43.75%) patients with MRTK and five (5/21, 23.81%) patients with EERT had metastases at diagnosis, and quite a few number of cases occurred tumor rupture (26.42%). Among the 53 patients, 40 (75.47%) patients died, 10 (18.87%) patients survived, and 3 patients (5.66%) were lost to follow‐up. Among the 40 dead patients, 38 patients died from rapid progression of the disease or tumor recurrence, and 2 patients died of severe postoperative complications. Most of the recurrent or relapsed cases (94.11%) occurred within 8 months, with a median time of 76 days after diagnosis. The overall survival rates of 3 years and 5 years for the entire cohort were 23.71% and 18.44%, respectively. After survival analysis, it was clear that a younger age at diagnosis and distant stage patients had relatively poor outcomes. The effect of treatment was the most difficult to analyze because patients were not treated uniformly. Statistically significant differences in survival were noted among patients treated with standard chemotherapy, total resection, and radiotherapy. Conclusion Extracranial MRT is still a highly aggressive tumor in children. Younger patients and those suffering from metastatic disease were most likely to have a poor outcome because of rapid progression or recurrence of the tumor. Implications for Practice This is the largest single‐institutional report that investigates the clinical characteristics and outcomes of extracranial malignant rhabdoid tumor (MRT) in China. Our study showed that gross hematuria and tumor rupture were typical characteristics of malignant rhabdoid tumor of the kidney. After survival analysis, it was found that the advanced stage of the tumor and an age ≤12 months at diagnosis were significantly associated with poorer survival. Although extracranial MRT is still a highly aggressive tumor in children, multimodal treatment approach, including chemotherapy, surgery, and radiotherapy, should be employed for this disease.

In the incorporation of the catalyst (H2O)n (n = 1–3) into the HO2 + HO2 → H2O2 + 3O2 reaction, the catalytic effect of water, water dimers and water trimers is mainly derived from the contribution of a single water vapor molecule by a stepwise route.

The effects of acidic (FA), neutral (WM) and basic (AM) catalysts on the energetic and kinetic aspects of the HO2 + Cl reaction have been studied. At 298 K, the catalytic order of FA, WM and AM is WM > FA > AM.

The hydrolysis of CH2OO is not only a dominant sink for the CH2OO intermediate in the atmosphere but also a key process in the formation of aerosols. Herein, the reaction mechanism and kinetics for the hydrolysis of CH2OO catalyzed by the precursors of atmospheric aerosols, including H2SO4, H2SO4···H2O, and (H2SO4)2, have been studied theoretically at the CCSD­(T)-F12a/cc-pVDZ-F12//B3LYP/6-311+G­(2df,2pd) level. The calculated results show that the three catalysts decrease the energy barrier by over 10.3 kcal·mol–1; at the same time, the product formation of HOCH2OOH is more strongly bonded to the three catalysts than to the reactants CH2OO and H2O, revealing that small clusters of sulfuric acid promote the hydrolysis of CH2OO both kinetically and thermodynamically. Kinetic simulations show that the H2SO4-assisted reaction is more favorable than the H2SO4···H2O- (the pseudo-first-order rate constant being 27.9–11.5 times larger) and (H2SO4)2- (between 2.8 × 104 and 3.4 × 105 times larger) catalyzed reactions. Additionally, due to relatively lower concentration of H2SO4, the hydrolysis of CH2OO with H2SO4 cannot compete with the CH2OO + H2O or (H2O)2 reaction within the temperature range of 280–320 K, since its pseudo-first-order rate ratio is smaller by 4–7 or 6–8 orders of magnitude, respectively. However, the present results provide a good example of how small clusters of sulfuric acid catalyze the hydrolysis of an important atmospheric species.

The hydrolysis reaction of CH2OO with water and water clusters is believed to be a dominant sink for the CH2OO intermediate in the atmosphere. However, the favorable route for the...

The decomposition network of ammonium perchlorate (AP) is essential for combustion performance and safety of solid propellants, while the detailed reaction pathway during thermolysis is far from clear due to the ultrafast and complex reactions involved. Herein, we present direct atomic simulations of AP thermal decomposition and propose a detailed decomposition network to fill the missing piece in the kinetic models by using a neural network model derived from ab initio calculations. The proton transfer is the dominant channel (NH 4 + ClO 4 → NH 3 + HClO 4 ), which is also observed in previous mass spectra experiments. In addition, gas products from decomposition play a critical role in promoting the decomposition of solid AP. For example, the H abstraction reaction by OH is found to be a critical pathway for AP decomposition. These simulations provide atomic insights into the complex reaction dynamics of AP and can be extended to investigate the reaction mechanism of novel energetic materials.

The H2O2 + HO → HO2 + H2O reaction is an important reservoir for both radicals of HO and HO2 catalyzing the destruction of O3.