Ru Single Atom Dispersed on MoS2/MXene for Enhanced Sulfur Reduction Reaction in Lithium-Sulfur Batteries.

The high theoretical energy density (2600 Wh kg-1) and low cost of lithium-sulfur batteries (LSBs) make them an ideal alternative for the next-generation energy storage system. Nevertheless, severe capacity degradation and low sulfur utilization resulting from shuttle effect hinder their commercialization. Herein, Single-atom Ru-doped 1T/2H MoS2 with enriched defects decorates V2C MXene (Ru-MoS2/MXene) produced by a new phase-engineering strategy employed as sulfur host to promote polysulfide adsorption and conversion reaction kinetics. The Ru single atom-doped adjusts the chemical environment of the MoS2/MXene to anchor polysulfide and acts as an efficient center to motivate the redox reaction. In addition, the rich defects of the MoS2 and ternary boundary among 1T/2H MoS2 and V2C accelerate the charge transfer and ion movements for the reaction. As expected, the Ru-MoS2/MXene/S cathode-based cell exhibits a high-rate capability of 684.3 mAh g-1 at 6 C. After 1000 cycles, the Ru-MoS2/MXene/S cell maintains an excellent cycling stability of 696 mAh g-1 at 2 C with a capacity degradation as low as 0.02% per cycle. Despite a high sulfur loading of 9.5 mg cm-2 and a lean electrolyte-to-sulfur ratio of 4.3, the cell achieves a high discharge capacity of 726 mAh g-1.

Quantitatively Unveiling the Structure-Activity Relationship of Polyamide Nanofiltration Membranes with Complex Structures.

Nanofiltration polyamide (NF PA) membranes are widely used in seawater desalination and wastewater treatment due to their excellent permeability. The structure-activity relationship of PA membranes has attracted extensive attention in decades. In this work, NF PA membranes with planar structure, nodular structure, and peak-valley structure were constructed, and the pure water permeance was calculated by nonequilibrium molecular dynamics simulation to quantitatively investigate the structure-activity relationship between the microstructure and water permeance. Results showed that the peak-valley structure had the highest effective utilization rate of the membrane surface, which had the highest number of water molecules that passed through membranes per unit cross-sectional area (7.09). Furthermore, with the increase of the specific surface area ratio, the water permeance of the NF PA with peak-valley increased at a rate about 2.5 times than that of the planar NF PA. Therefore, some molecular scale insights were supplied about the structure-activity relationship of NF PA membranes, which is helpful for the fabrication of high-performance NF PA membranes.

Tailored Heterojunction Active Sites for Oxygen Electrocatalyst Promotion in Zinc-Air Batteries.

Rechargeable zinc-air batteries (ZABs) are promising energy storage systems due to their low-cost and safety. However, the working principle of ZABs is based on oxygen evolution reaction (OER) and oxygen reduction reaction (ORR), which display sluggish kinetic and low stability. Herein, this work proposes a novel method to design a heterogeneous CoP/CoO electrocatalyst on mesopore nanobox carbon/carbon nanotube (CoP/CoO@MNC-CNT) that enriched active sites and synergistic effect. Moreover, the well-defined heterointerfaces could lower the energy barrier for intermediate species adsorption and promote OER and ORR electrochemical performances. The CoP/CoO@MNC-CNT electrocatalyst presents a high half-wave potential of 0.838 V for ORR and a small overpotential of 270 mV for OER. The ZABs-based CoP/CoO@MNC-CNT air-cathode shows an open-circuit voltage of 1.409 V, the long-term cycle life of 500 h with a small voltage difference change of 7.7%. Additionally, the flexible ZABs exhibit highly mechanical stability, demonstrating their application potential in wearable electronic devices.

Novel Perylene-3, 4, 9, 10-tetracarboxylic dianhydride modified Zr-MOFs/Graphene oxide membrane for dye wastewater treatment.

A new type of composite membrane was prepared through the vacuum filtration self-assembly, in which, graphene oxide (GO) was the basic material, and the horizontal insertion material is product of perylene-3, 4, 9, 10-tetracarboxylic dianhydride (PTCDA) and UiO-66-NH2 (PTCDA-UiO-66-NH2). The leading role of Π-Π conjugate, auxiliary effect of hydrogen bonding during membrane preparation have been confirmed through Fourier transform infrared spectroscopy (FTIR), UV-visible spectrophotometer, Raman spectroscopy, and X-ray diffraction (XRD). The prepared GO@PTCDA-UiO-66-NH2 membrane had new nodular structure compared to GO membrane by scanning electron microscopy (SEM) and atomic force microscopy (AFM), which promoted the water transport. In addition, the insertion of PTCDA-UiO-66-NH2 narrowed the actual filtration spacing between GO sheets, and PTCDA-UiO-66-NH2 could also adsorbed dye laterally. Experiments showed that the permeance of GO@PTCDA-UiO-66-NH2 membrane was 1.7 times of GO membrane, and the removal of methyl blue, congo red, crystal violet and disperse black 9 was close to 100%. Under extreme pH, high salt concentration and multiple recycling, its separation ability was still excellent. The GO@PTCDA-UiO-66-NH2 membrane constituted a unique synergistic structure of vertical-screening and horizontal-adsorption, which successfully overcame the trade-off effect and obtained excellent stability of structure and performance. Therefore, GO@PTCDA-UiO-66-NH2 membrane had great potential in practical applications.

The role of ultrasonography in the diagnosis of gallbladder cancer.

OBJECTIVE: To investigate the value of ultrasonography in the diagnosis of gallbladder cancer in a community. METHODS: A total of 24 cases of gallbladder carcinoma confirmed by operation and pathology were retrospectively analyzed. RESULTS: There were 14 cases (14/24) of gallbladder cancer preoperatively diagnosed by normal scale ultrasound and 10 cases (10/24) of accidental gallbladder cancer diagnosed. The diagnostic sensitivity was 58.33%. Irregular thickening of gallbladder wall was found in the 14 cases of preoperative diagnosis of gallbladder carcinoma. There were 22 cases of gallbladder cancer complicated with gallstones (22/24) and 2 cases without gallstones (2/24), among which 18 were multiple gallstones and 4 cases (4/24) were single gallstone. Signal of blood flow can be detected in the lesion of gallbladder wall in 7 cases (7/14). CONCLUSION: The evaluation of the gallbladder in patients with high risk factors should be emphasized in community ultrasound examinations. KEY WORDS: Conventional ultrasound mode, Gallbladder carcinoma incidental gallbladder carcinoma, Gallstone, Thickening of the gallbladder wall.

Modulating Orientational Order to Organize Polyhedral Nanoparticles into Plastic Crystals and Uniform Metacrystals.

In nanoparticle self-assembly, the current lack of strategy to modulate orientational order creates challenges in isolating large-area plastic crystals. Here, we achieve two orientationally distinct supercrystals using one nanoparticle shape, including plastic crystals and uniform metacrystals. Our approach integrates multi-faceted Archimedean polyhedra with molecular-level surface polymeric interactions to tune nanoparticle orientational order during self-assembly. Experiments and simulations show that coiled surface polymer chains limit interparticle interactions, creating various geometrical configurations among Archimedean polyhedra to form plastic crystals. In contrast, brush-like polymer chains enable molecular interdigitation between neighboring particles, favoring consistent particle configurations and result in uniform metacrystals. Our strategy enhances supercrystal diversity for polyhedra comprising multiple nondegenerate facets.

Ultrasonographic diagnosis of early unruptured tubal pregnancy in a community hospital.

OBJECTIVE: To investigate ultrasonographic characteristics and diagnostic approaches of unruptured tubal pregnancy (UTP). METHODS: One hundred forty-six cases of early tubal pregnancy, which were confirmed surgically, were analyzed. RESULTS: Among 146 cases of UTP, 130 were diagnosed by ultrasonography. Furthermore, 16 cases of UTP were missed by ultrasonography. A total of 130 patients had a mass detected by ultrasonography, among whom the mass and ipsilateral ovary were distinguishable in 102. The embryo sac type was found in 40.00% (52/130), while the heterogeneous mass type was found in 60.00% (78/130) of patients. The maximum length and diameter of the ectopic pregnancy mass ranged from 10 to 68 mm (mean size, 26.42 ± 11.39 mm). No blood flow was observed in or around the mass in 67.69% (88/130) of patients. Lateral tubal thickening of the mass was found in 47.69% (62/130) of patients. Endometrial thickness was ≤10 mm in 67.80% (99/146) of patients. The intima was mostly hyperechoic in 72.60% (106/146) of patients. CONCLUSION: A paraovarian mass, thickened fallopian tube, uterine endometrium with a thickness of ≤10 mm, and high echo are important indicators of early UTP. Ultrasound examinations should focus on these indicators to help improve detection of early tubal pregnancy.

Tailored polyimide as positive electrode and polyimide-derived carbon as negative electrode for sodium ion full batteries.

Organic electrode materials have secured a distinctive place among the auspicious choices for modern energy storage systems due to their resource sustainability and environmental friendliness. Herein, a novel all-organic electrode-based sodium ion full battery is demonstrated using 1,4,5,8-naphthalenetetracarboxylic dianhydride (NTCDA) as raw material for the assembly of positive and negative electrodes. Both the electrodes exhibit excellent cycling stability and rate performance. The fabricated organic sodium ion full battery not only displays a high initial capacity of 157 mA h g-1 with an average battery voltage of 1.47 V under the current density of 100 mA g-1, but also delivers a high energy density of 254 W h kg-1 and a high power density of 614 W kg-1. These sodium ion batteries with organic positive and negative electrode materials can provide a new way for energy storage devices.

Application of oral contrast trans-abdominal ultrasonography for initial screening of gastric cancer in rural areas of China.

BACKGROUND: The present study is aimed at assessing the efficacy of oral contrast trans-abdominal ultrasonography (OCTU) as an initial screening tool for gastric cancer in rural areas of China. METHODS: All subjects that were enrolled from Chongming County, Shanghai, China. Subjects in the symptomatic group underwent both OCTU and gastroscopic biopsy. OCTU was performed by experienced ultrasonic physicians in a blinded fashion. RESULTS: In the symptomatic group, 643 patients were enrolled; diagnoses included low risk diseases gastritis (68.9%), polyps (4.0%) and benign ulcers (8.7%), and high risk diseases intraepithelial neoplasia (1.9%), cancer (15.9%) and other lesions (0.6%). Abnormalities were detected by OCTU in 404 subjects (62.8%). High risk diseases were significantly correlated with objective OCTU parameters, including thickness of stomach wall, loss of stratification and hypoechoic mess. With the cut-off value of thickness being set at 7mm, the sensitivity and specificity of OCTU for detecting high risk diseases were 81.3% and 68.8%, respectively. When cut-off value of risk index based on OCTU parameters was set at 3 points, the sensitivity and specificity were 94.1% and 71.4%, respectively. CONCLUSION: OCTU can detect high risk gastric diseases with high sensitivity and specificity providing an initial screening tool for gastric cancer.