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Solid-state metallic potassium batteries (SSMPBs) afresh have attracted incremental attention because of their potential to supplement solid-state metallic lithium batteries. However, SSMPBs suffer poor electrochemical performances due to the low ionic conductivity of solid electrolytes and huge electrode/electrolyte interfacial resistance. Herein, high-rate SSMPBs are achieved by in situ ring-opening polymerization of 1,3-dioxolane with succinonitrile as a plasticizer and Al(OTf) 3 as the catalyst, where the succinonitrile enables short-chain polyether electrolytes. The in situ polymerized electrolytes deliver a high ionic conductivity of 4.5 × 10 -5 S cm -1 at room temperature and excellent stabilities at high oxidation potentials (4.2 V vs K + /K) and against metallic K anodes. All these result in SSMPBs with a discharge capacity of 69 mAh g -1 under a high rate of 100 mA g -1 and a retention of 88.8% after 100 cycles, and the rate and capacity retention are higher than those in previous work on SSMPBs.

Aim: To investigate the value of two-dimensional (2D) and three-dimensional (3D) double contrast-enhanced ultrasonography (DCUS) imaging for evaluation of gastric lesions., Methods: 2D and 3D DCUS imaging with both oral and intravenous administrations of contrast agents was used to assess gastroscopiclly-confirmed gastric lesions in 46 patients with benign and malignant diseases. Initially, liquid-based ultrasound contrast agent (Xinzhang®) was given orally at dose of 500-600 mL for conventional ultrasound examination of the gastric lesions, and then a microbubble-based contrast agent (SonoVue) was injected intravenously at dose of 1.2-2.4 mL in bolus fashion to assess the perfusion pattern of the lesions using contrast imaging modes. The parameters derived from time-intensity curves including the arrival time (AT), time to peak (TTP), peak intensity (PI) and enhanced intensity (EI) were measured on the 2D DCUS imaging. 3D DCUS of the lesions was acquired to demonstrate the value of this imaging mode., Results: There were 22 cases with benign lesions including chronic gastritis (n = 5), gastric ulcer (n = 9), gastric polyps (n = 3), gastric stromal tumors (n = 5), and 24 cases with malignant lesions including gastric cancer (n = 20), gastric cardia carcinoma (n = 3) and post-operative recurrent gastric cancer (n = 1) in the study. The oral contrast-enhanced ultrasonography (CEUS) imaging of the stomach clearly demonstrated the anatomy of the stomach and morphologic features of gastric lesions. With optimal scanning window and imaging display under oral CEUS, intravenous CEUS clearly showed the perfusion of gastric lesions with various characteristic manifestations. Both 2D and 3D DCUS images clearly demonstrated normal gastric wall as a three-layer structure, from the inside out, hyperechoic mucosa, hypoechoic muscularis and hyperechoic serosa, respectively. There were statistical significant differences of AT (8.68 ± 2.06 vs 10.43 ± 2.75, P = 0.017), PI (34.64 ± 6.63 vs 29.58 ± 8.22, P = 0.023) and EI (29.72 ± 6.69 vs 22.66 ± 7.01, P = 0.001) between malignant lesions and normal gastric wall. However, no differences of AT, PI and EI between benign lesions and normal gastric wall tissue were found. 3D DCUS could intuitively display morphological features and vascularities of the lesions with multiplanar and volume views. 3D DCUS imaging provided comprehensive information complementary to 2D imaging. The crater or wellhead appearances and feeding vessels as well as distorted nourishing vasculature of gastric carcinoma were better seen with 3D imaging than 2D imaging., Conclusion: DCUS imaging can simultaneously display the anatomic and perfusion features of gastric lesions. 3D DCUS can provide additional information to 2D DCUS for evaluation of gastric lesions.