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Multistaged discharge constructing heterostructure with enhanced solid-solution behavior for long-life lithium-oxygen batteries.
Inferior charge transport in insulating and bulk discharge products is one of the main factors resulting in poor cycling stability of lithium-oxygen batteries with high overpotential and large capacity decay. Here we report a two-step oxygen reduction approach by pre-depositing a potassium carbonate layer on the cathode surface in a potassium-oxygen battery to direct the growth of defective film-like discharge products in the successive cycling of lithium-oxygen batteries. The formation of defective film with improved charge transport and large contact area with a catalyst plays a critical role in the facile decomposition of discharge products and the sustained stability of the battery. Multistaged discharge constructing lithium peroxide-based heterostructure with band discontinuities and a relatively low lithium diffusion barrier may be responsible for the growth of defective film-like discharge products. This strategy offers a promising route for future development of cathode catalysts that can be used to extend the cycling life of lithium-oxygen batteries
4,4′-(Ethene-1,2-diyl)dipyridinium bis[4-(2-carboxybenzoyl)benzoate]
In the crystal structure of the title compound, C12H12N2
2+·2C15H9O5
−, the cation has site symmetry with the mid-point of C=C bond located on an inversion center. The two benzene rings of the anion are oriented at a dihedral angle 85.87 (6)°. In the crystal, intermolecular O—H⋯O and N—H⋯O hydrogen bonds link the cations and anions into supramolecular double chains, which are further connected into a three-dimensional network through intermolecular C—H⋯O and π–π stacking between parallel pyridine rings [centroid–centroid distance = 3.4413 (12)Å] and between parallel benzene rings [centroid–centroid distance = 3.6116 (14)Å]
3-Chloro-5-(trifluoromethyl)pyridin-2-amine
In the title compound, C6H4ClF3N2, an intermediate in the synthesis of the fungicide fluazinam, the F atoms of the trifluoromethyl group are disordered over two sites in a 0.683 (14):0.317 (14) ratio. In the crystal structure, centrosymmetric dimers arise from pairs of N—H⋯N hydrogen bonds
Synchronous Gastric Carcinoma and Nodal Malignant Lymphoma: A Rare Case Report and Literature Review
Synchronous double malignancies of gastric carcinoma (GC) and malignant lymphoma (ML) are rare and very difficult to treat. We report a case of synchronous GC and nodal ML, regarding which clinical and pathological features and treatment are discussed. A 68-year-old woman with a history of inguinal hernia was admitted for abdominal pain and high fever and subsequently underwent herniorrhaphy, but the fever remained. Computerized tomography showed a stomach mass and multiple enlarged lymph nodes in the abdominal cavity and inguinal regions. Gastric adenocarcinoma coexistent with advanced in situ follicular lymphoma was confirmed by endoscopy, biopsy of inguinal lymph nodes and bone marrow examination. Two chemotherapy regimens, R-CHOP (rituximab, cyclophosphamide, perarubicin, vincristine and prednisone) and systemic therapy (5-fluorouracil and calcium folinate) combined with regional perfusion (oxaliplatin and etoposide) through the left gastric artery were performed at intervals against ML and GC, respectively. Partial remission in both tumors was achieved after 4 courses of treatment, but the patient finally died of heart failure. Scrupulous biopsy of non-draining lymph nodes in patients with gastrointestinal carcinomas is supposed to improve the diagnostic rate of simultaneous nodal ML. The interval chemotherapy strategy with two independent regimens is beneficial for such patients, especially for those unable to tolerate major surgery
Laboratory study on low-temperature coal spontaneous combustion in the air of reduced oxygen and low methane concentration
Provedena su laboratorijska ispitivanju u svrhu proučavanja spontanog izgaranja ugljena na niskoj temperaturi (30 ÷ 200 °C) u zraku s reduciranim kisikom (10 ÷ 21 %) i niskim koncentracijama metana (0 ÷ 3 %). Analiziralo se stvaranje ugljičnog monoksida kod spontanog izgaranja ugljena. Rezultati ispitivanja pokazuju da i koncentracije kisika i metana djeluju na spontano izgaranje ugljena. Pri datoj koncentraciji kisika koncentracija metana u zraku je imala pozitivan učinak na spontano izgaranje ugljena, a učinak se povećao s koncentracijom metana. Taj je učinak oslabio i smanjio se porastom temperature. Početna je temperature ugljičnog dioksida, kod koje se ugljični monoksid počeo javljati, porasla smanjenjem koncentracije kisika u zraku, a porast je donekle smanjen povećanjem koncentracije metana u zraku. Međutim, kako se koncentracija kisika smanjivala do određene vrijednosti, koncentracija metana je pokazivala malo ili nikakvog utjecaja na spontano izgaranje ugljena. Uzete su u obzir karakteristike ugljena kod niske temperature sorpcije kisika i metana kako bi se objasnili rezultati. Dobiveni rezultati su od posebne koristi u predviđanju i praćenju spontanog izgaranja ugljena u plinovitim ugljenokopima.Laboratory tests were conducted to study coal spontaneous combustion at low-temperature (30 ÷ 200 °C) in the air of reduced oxygen (10 ÷ 21 %) and low methane concentrations (0 ÷ 3 %). The production of carbon monoxide in coal spontaneous combustion was analysed. The test results show that both oxygen and methane concentrations affect coal spontaneous combustion. At given oxygen concentration the methane concentration in air had a positive impact on coal spontaneous combustion and the impact increased with methane concentration. This impact was weakened and diminished with the rise of temperature. The initial carbon dioxide temperate at which carbon monoxide started to appear increased with the reduction of oxygen concentration in the air and the increase was somewhat negated by the presence of increased methane concentration in air. However, as the oxygen concentration reduced to a certain value, methane concentration showed little or no influence on coal spontaneous combustion. The low temperature sorption characteristics of oxygen and methane by coal were applied to explain the results. The findings in this study are particularly useful in the prediction and control of coal spontaneous combustion in gassy coal mines
Bis(μ-4-nitrophthalato)bis[diaqua(1,10-phenanthroline)manganese(II)]
In the title compound, [Mn2(C8H3NO6)2(C12H8N2)2(H2O)4], the MnII atom in the centrosymmetric binuclear unit has a distorted octahedral geometry and is coordinated by a chelating 1,10-phenanthroline ligand, two monodentate carboxylate anions from two 4-nitrophthalates and two coordinated water molecules. The two MnII ions in the molecule are bridged by two 4-nitrophthalate anions, both in a bis-monodentate mode, which finally leads to the formation of the binuclear unit. Intramolecular O—H⋯O hydrogen bonds between the coordinated and uncoordinated O atoms of one monodentate carboxylate group and the corresponding coordinated water molecules result in an eight-membered and two six-membered rings. In the crystal structure, intermolecular O—H⋯O hydrogen bonds link the dinuclear molecules into supramolecular chains propagating parallel to [100]
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