Timely analysis of the laboratory characteristics associated with 2019 novel coronavirus pneumonia can assist with clinical diagnosis and prognosis. This study is a collection of clinical data from 54 hospitalized adult patients diagnosed with COVID-19 in the Zhongfa Xincheng district . The average age of the patients was 61.8 ± 14.5 years, and the predominant age group was 50-79. The proportion of critical-type patients with comorbidities was higher than that of severe-type patients. Lymphocyte counts were significantly reduced in routine bloodwork for all patients, but significantly lower in critical-type patients than that in severe-type patients. Prolongation of prothrombin times (PT) and elevation of fibrinogen degradation products (FDPs) and D-dimers (D-Ds) were detected in coagulation function tests, and more significant changes were observed in critical-type patients compared to severe-type patients. Serum ferritin levels were sensitive to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection but could not be used for disease assessment. In addition, levels of two inflammatory factors, soluble interleukin-2 receptor (sIL-2R) and interleukin-6 (IL-6) were significantly increased in all patients, but higher in critical-type patients than in severe-type patients. Moreover, kidney injury was the second-most common organ affected by COVID-19 followed by heart and liver. Kidney and heart injury were more severe in critical-type patients than in severe-type patients. All of the 31 severe-type patients recovered. Of the criticaltype patients, six died and 17 recovered. The length of hospital stay for critical-type patients was significantly longer for severe-type patients. In summary, increased lymphocyte counts, prolonged PT, secondary increases in fibrinolytic activity and increases in sIL-2R and IL-6 are typical features of COVID-19 and are associated with disease severity.

The hydrogen evolution reaction (HER) usually has sluggish kinetics in alkaline solution due to the difficulty in forming binding protons.Herein we report an electrocatalyst in which sulfur atoms are doping in the oxygen vacancies (V O )of inverse spinel NiFe 2 O 4 (S-NiFe 2 O 4 )t oc reate active sites with enhanced electron transfer capability.T his electrocatalyst has an ultralowo verpotential of 61 mV at the current density of 10 mA cm À2 and long-term stability of 60 ha t1 .0 Acm À2 in 1.0 MKOH media. In situ Raman spectroscopyrevealed that S sites adsorb hydrogen adatom (H*) and in situ form S-H*, which favor the production of hydrogen and boosts HER in alkaline solution. DFT calculations further verified that S introduction lowered the energy barrier of H 2 Od issociation. Both experimental and theoretical investigations confirmed S atoms are active sites of the S-NiFe 2 O 4 .

Manipulating the active species and improving the structural stabilization of sulfur-containing catalysts during the OER process remain a tremendous challenge. Herein, we constructed NiO/NiS 2 and FeÀ NiO/NiS 2 as catalyst models to study the effect of Fe doping. As expected, FeÀ NiO/NiS 2 exhibits a low overpotential of 270 mV at 10 mA cm À 2 . The accumulation of hydroxyl groups on the surface of materials after Fe doping can promote the formation of highly active NiOOH at a lower OER potential. Moreover, we investigated the level of corrosion of MÀ S bonds and compared the stability variation of MÀ S bonds with Fe at different locations. Interestingly, Fe bonded with S in the bulk as the sacrificial agent can alleviate the oxidation corrosion of partial NiÀ S bonds and thus endow FeÀ NiO/NiS 2 long-term durability. This work could motivate the community to focus more on resolving the corrosion of sulfur-containing materials.

The regulation of mechanism on the electrocatalysis process with multiple reaction pathways is more efficient and essential than conventional material engineering for the enhancement of catalyst performance. Here, by using oxygen evolution reaction (OER) as a model, which has an adsorbate evolution mechanism (AEM) and a lattice oxygen oxidation mechanism (LOM), we demonstrate a general strategy for steering the two mechanisms on various La x Sr 1− x CoO 3−δ . By delicately controlling the oxygen defect contents, the dominant OER mechanism on La x Sr 1− x CoO 3−δ can be arbitrarily transformed between AEM-LOM-AEM accompanied by a volcano-type activity variation trend. Experimental and computational evidence explicitly reveal that the phenomenon is due to the fact that the increased oxygen defects alter the lattice oxygen activity with a volcano-type trend and preserve the Co 0 state for preferably OER. Therefore, we achieve the co-optimization between the activity and stability of catalysts by altering the mechanism rather than a specific design of catalysts.

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most valuable fundamental chemicals in various chemical industries, medical industries, and environmental remediation. [2] Interestingly, both these two focuses can be realized by the ORR process via different reaction routes or mechanisms. In detail, ORR with a complex multielectron process can proceed by two pathways, including the four-electron (4e − ) or two-electron 2e − ORR process to generate H 2 O or H 2 O 2 , respectively. [3] In the former pathway, oxygen is directly reduced to the final OHwhich is usually facilitated by platinum (Pt)based noble-metal electrocatalysts or some non-noble materials; while for the latter one, the first formed peroxide intermediateswill either diffuse away from the disk electrode or continues to be reduced to form OH − (H 2 O 2 + 2e − → 2OH − ), which is commonly occurred on the surface of carbonaceous materials or transition-metal oxides. [4] As illustrated, the mechanism for ORR is strongly affected by the surface structure, coordination environment, really exposed active centers, or crystal types of catalysts. [5] Among all the reported catalysts, typical mixed-metal cobalt manganese oxides (Mn x Co 3−x O 4±δ , 0 ≤ x ≤ 3, where δ indicates the oxygen non-stoichiometry) are usually deemed as promising catalysts in the oxygen electrochemical reaction, owing to high element abundance, considerable electro-activity, controllable tetrahedral and octahedral coordination, rich valence states. [6] Currently, various kinds of Mn-Co oxides have been reported for ORR; The oxygen reduction reaction (ORR) has been demonstrated as a critical technology for both energy conversion technologies and hydrogen peroxide intermediate production. Herein, an in situ oxygen evolution reaction (OER) surface evolution strategy is applied for changing the surface structure of MnCo 2 O 4 oxide with tetrahedral and octahedral cations vacancies to realize reaction pathway switching from 2e − ORR and 4e − ORR. Interestingly, the as-synthesized MnCo 2 O 4 -pristine (MnCo 2 O 4 -P) with the highest surficial Mn/Co octahedron occupation favors two electrons reaction routes exhibiting high H 2 O 2 selectivity (≈80% and reaches nearly 100% at 0.75 V vs RHE); after surface atoms reconstruction, MnCo 2 O 4 -activation (MnCo 2 O 4 -A) with the largest Mn/ Co tetrahedron occupation present excellent ORR performance through the four-electron pathway with an ultrahigh onset potential and half-wave potential of 0.78 and 0.92 V, ideal mass activity (MA), and turnover frequencies (TOF) values. Density functional theory (DFT) calculations reveal the concurrent modulations of both Co and Mn by the surface reconstructions, which improve the electroactivity of MnCo 2 O 4 -A toward the 4e − pathway. This work provides a new perspective to building correlation of OER activation-ORR property, bringing detailed understating for reaction route transformation, and thus guiding the development of certain electrocatalysts with specific purposes.

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