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Metallic carbohydrazide perchlorates (M[(N2H3)2C = O](ClO4)2, M2+ = Mn2+, Fe2+, Co2+, Ni2+, Zn2+ and Cd2+, simplified as MCPs) are a series of energetic primary explosives, among which ZnCP and CdCP are already applied in civilian/military fields. The six MCPs possess similar structures but demonstrate different energetic performances in their decomposition, which are obviously determined by their different central metals. Here, we apply DFT and Car–Parrinello molecular dynamics (CPMD) to understand the electronic structures and decomposition pathways of the MCPs. Based on the results, the crystal MCPs with larger electronic band gaps show lower impact sensitivity. However, the friction sensitivity of MCPs is dominated by the strength of their intermolecular O⋯H interactions. In the CPMD simulations, we obtained a different conclusion from the traditional viewpoint, where the decomposition is spontaneous from the cleavage of M–N bonds. Indeed, there are two stages in the decomposition of the MCPs, based on our calculations: (I) nonspontaneous 3-step departure of the CHZ groups and (II) spontaneous exoergic decomposition pathways of the CHZ groups triggered by the transfer of O/H radicals. Our study provides a systematic study of the MCP family, which also affords a new route for understanding the relationship between the energetic properties and electronic structures of energetic metal complexes. [ABSTRACT FROM AUTHOR]

We present a facile synthesis of highly dispersed Ce and Fe metal oxide nanoparticles (NPs) with the size distribution of about 1–2 nm on reduced graphene oxide (RGO). The obtained Ce-Fe/RGO hybrid material is structurally characterized by TEM, XRD, XPS, Raman, BET, and H2-TPR. The results show that the addition of Fe promotes the formation of high surface area Ce-Fe/RGO hybrid material due to the inhibition of different species on crystal growth. The enhanced adsorption properties mainly come from the monolayer dispersion and the reduced particle size of NPs on the graphene. The driving force for the adsorption is the electrostatic action between adsorbent materials with positive electricity and CR with negative electricity, and the NPs and RGO together interact with the Congo red (CR) in the adsorption process. The Ce-Fe/RGO hybrid material exhibits a high adsorption capacity of 179.5 mg g−1for the CR in water, suggesting their potential use in water treatment. [ABSTRACT FROM PUBLISHER]

Abstract: K-birnessite MnO2 encapsulated in carbon nanotubes (CNTs) was prepared by spontaneous redox between KMnO4 and CNTs at room temperature and exhibited excellent catalytic activity for selective oxidation of benzyl alcohol. Research results showed that the enhanced catalytic activity can be attributed to the easier reducibility of MnO2 confined in CNTs, the inhibition for Mn4+ into Mn3+ and the stability of catalysts due to the existence of K species. [Copyright &y& Elsevier]

Abstract: ZrO2-doped TiO2 hollow nanospheres with anatase phase are efficiently fabricated via functionalized negatively charged polystyrene (PS) spheres without any surfactant or polyelectrolyte. The resulting Ti1− x Zr x O2 (hereafter denoted as TZ) hollow nanospheres are characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), powder X-ray diffraction (XRD), Laser Raman spectroscopy (LRS), X-ray photoelectron spectroscopy (XPS), X-ray fluorescence spectroscopy (XRF), nitrogen sorption, and UV–vis diffuse reflectance spectroscopy (UV–vis). The Zr4+ incorporation decreases the anatase crystallite size, increases the specific surface area, and changes the pore size distribution. Furthermore, it induces enrichment of electron charge density around Ti4+ ions and blueshift of absorption edges. The TZ hollow nanospheres doped with moderate ZrO2 (molar ratio, Ti:Zr=10:1) exhibit better photocatalytic activity than the other samples for the degradation of rhodamine B in aqueous solution, which is correlated with the effect of Zr4+ doping on the physicochemical properties in terms of surface structures, phase structures, and the electronic structures. [Copyright &y& Elsevier]

Metallic carbohydrazide perchlorates (M[(N 2 H 3 ) 2 C = O](ClO 4 ) 2 , M 2+ = Mn 2+ , Fe 2+ , Co 2+ , Ni 2+ , Zn 2+ and Cd 2+ , simplified as MCPs) are a series of energetic primary explosives, among which ZnCP and CdCP are already applied in civilian/military fields. The six MCPs possess similar structures but demonstrate different energetic performances in their decomposition, which are obviously determined by their different central metals. Here, we apply DFT and Car-Parrinello molecular dynamics (CPMD) to understand the electronic structures and decomposition pathways of the MCPs. Based on the results, the crystal MCPs with larger electronic band gaps show lower impact sensitivity. However, the friction sensitivity of MCPs is dominated by the strength of their intermolecular O⋯H interactions. In the CPMD simulations, we obtained a different conclusion from the traditional viewpoint, where the decomposition is spontaneous from the cleavage of M-N bonds. Indeed, there are two stages in the decomposition of the MCPs, based on our calculations: (I) nonspontaneous 3-step departure of the CHZ groups and (II) spontaneous exoergic decomposition pathways of the CHZ groups triggered by the transfer of O/H radicals. Our study provides a systematic study of the MCP family, which also affords a new route for understanding the relationship between the energetic properties and electronic structures of energetic metal complexes.

Objective: To explore the effect of regional synergistic treatment system on the treatment time and short-term prognosis of patients with ST-segment elevation myocardial infarction (STEMI)., Methods: A retrospective analysis of the clinical data of STEMI patients who admitted to emergency center of Suzhou Kowloon Hospital Affiliated to Shanghai Jiaotong University School of Medicine and underwent primary percutaneous coronary intervention (PPCI) from January 2013 to January 2017 were conducted. All patients were divided into two groups, group A was the patients who underwent the PPCI before the establishment of the acute chest pain area co-treatment system (from January 2013 to December 2014), and group B was the patients who received the treatment after the establishment of the area co-treatment system (from January 2015 to January 2017). The length of time from onset of symptoms to the balloon dilatation (S2B), the length of time from the first medical contact to the balloon dilatation (FMC2B), the length of time from entering the gate of hospital to the balloon dilatation (D2B), and the incidence of 90-day end point events (including heart failure, all-cause death, and other related adverse events) were collected. The relations of the establishment of the acute chest pain area co-treatment system and the incidence of 90-day end point events were analyzed by multivariable Logistic regression analysis., Results: Among the 221 enrolled patients with STEMI, 83 patients were in group A and 138 patients were in group B respectively. Compared with group A, S2B time [minutes: 180 (140, 210) vs. 201 (154, 225)], FMC2B time [minutes: 89 (78, 100) vs. 94 (83, 107)] and D2B time [minutes: 66 (62, 70) vs. 85 (72, 99)] were significantly shortened in group B (all P < 0.05), the incidence of 90-day end point events were significantly decreased (heart failure: 20.3% vs. 32.5%, all-cause death: 1.4% vs. 7.2%, other related adverse events: 23.2% vs. 36.1%, all P < 0.05). It was shown by multivariable Logistic regression analysis that the establishment of the acute chest pain area co-treatment system could lower the incidence of 90-day end point events [heart failure: odds ratio (OR) = 1.904, 95% confidence interval (95%CI) = 0.968-1.004, P = 0.048; all-cause death: OR = 11.724, 95%CI = 0.955-1.048, P = 0.013; other related adverse events: OR = 1.925, 95%CI = 1.049-3.530, P = 0.034]., Conclusions: The construction of regional synergistic treatment system can shorten the emergency treatment time of STEMI patients and reduce the incidence of 90-day end point events including heart failure and death.