53 research outputs found
Ampere-hour-scale soft-package potassium-ion hybrid capacitors enabling 6-minute fast-charging
Extreme fast charging of Ampere-hour (Ah)-scale electrochemical energy storage devices targeting charging times of less than 10 minutes are desired to increase widespread adoption. However, this metric is difficult to achieve in conventional Li-ion batteries due to their inherent reaction mechanism and safety hazards at high current densities. In this work, we report 1 Ah soft-package potassium-ion hybrid supercapacitors (PIHCs), which combine the merits of high-energy density of battery-type negative electrodes and high-power density of capacitor-type positive electrodes. The PIHC consists of a defect-rich, high specific surface area N-doped carbon nanotube-based positive electrode, MnO quantum dots inlaid spacing-expanded carbon nanotube-based negative electrode, carbonate-based non-aqueous electrolyte, and a binder- and current collector-free cell design. Through the optimization of the cell configuration, electrodes, and electrolyte, the full cells (1 Ah) exhibit a cell voltage up to 4.8 V, high full-cell level specific energy of 140 Wh kg-1 (based on the whole mass of device) with a full charge of 6 minutes. An 88% capacity retention after 200 cycles at 10 C (10 A) and a voltage retention of 99% at 25 ± 1 °C are also demonstrated
Emergent facilitation by random constraints in a facilitated random walk model of glass
The physics of glass has been a significant topic of interest for decades. Dynamical facilitation is widely believed to be an important characteristic of glassy dynamics, but the precise mechanism is still under debate. We propose a lattice model of glass called the facilitated random walk (FRW). Each particle performs a continuous time random walk in the presence of its own random local kinetic constraints. The particles do not interact energetically. Instead, they interact kinetically with a hopping rate resampling rule under which motions of a particle can randomly perturb the local kinetic constraints of other particles. This dynamic interaction is reversible, following a rate restoration rule. A step-by-step reversal of the particle motions exactly restores the previous constraints, modeling randomness quenched in the configuration space of glass. The model exhibits stretched exponential relaxation and dynamical heterogeneity typical of glasses. Despite the lack of an explicit facilitation rule, the FRW shows facilitation behaviors closely analogous to those of the kinetically constrained models (KCM). The FRW is a coarse-grained version of the distinguishable particle lattice model (DPLM) and this exemplifies that compatible defect and atomistic models can complement each other in the study of glass
Finishing the euchromatic sequence of the human genome
The sequence of the human genome encodes the genetic instructions for human physiology, as well as rich information about human evolution. In 2001, the International Human Genome Sequencing Consortium reported a draft sequence of the euchromatic portion of the human genome. Since then, the international collaboration has worked to convert this draft into a genome sequence with high accuracy and nearly complete coverage. Here, we report the result of this finishing process. The current genome sequence (Build 35) contains 2.85 billion nucleotides interrupted by only 341 gaps. It covers ∼99% of the euchromatic genome and is accurate to an error rate of ∼1 event per 100,000 bases. Many of the remaining euchromatic gaps are associated with segmental duplications and will require focused work with new methods. The near-complete sequence, the first for a vertebrate, greatly improves the precision of biological analyses of the human genome including studies of gene number, birth and death. Notably, the human enome seems to encode only 20,000-25,000 protein-coding genes. The genome sequence reported here should serve as a firm foundation for biomedical research in the decades ahead
Minimally invasive approach to managing brachiocephalic trunk cannulation complicating central venous catheterization: a case report
Abstract Background Central venous catheterization, crucial for device insertion, monitoring, medication, and fluid resuscitation, commonly uses the subclavian, internal jugular, and femoral veins. Despite its general safety, complications like arterial puncture can be life-threatening, requiring rapid diagnosis and treatment. Case presentation A 74-year-old woman in the recovery phase of cerebral infarction underwent right subclavian vein catheterization. The catheter was mistakenly placed in the brachiocephalic trunk, with its tip in the ascending aorta, as confirmed by computed tomography (CT) and digital subtraction angiography (DSA). With the high surgical risk and the complexity of endovascular treatment, catheter replacement was chosen. One month after the initial placement, the catheter was replaced with a smaller one, and another month later, it was retracted without complications. Follow-up CT and DSA revealed no leakage, with the patient’s vitals remaining stable. A three-month post-discharge phone follow-up confirmed the patient’s continued stability. Conclusion This case demonstrates the effective use of a catheter replacement technique as a minimally invasive repair method when other options are impractical. Ultrasound guidance is also recommended to improve the procedure’s accuracy and safety
Cyanoacrylate glue foreign body after CT-guided localization of a pulmonary nodule during video-assisted thoracoscopic surgery: a case report
Abstract
Background
A tracheal foreign body is a common airway aspiration that creates an emergency, which often causes unobserved respiratory problems and requires management. Iatrogenic tracheal foreign bodies are rarely observed, which results in tracheal obstruction. If the foreign body were removed from the tracheobronchial system, it would save lives. A similar case of a tracheal foreign body was focused on, which was caused by medical glue used during preoperative computed tomography localization of pulmonary nodules.
Case presentation
The foreign body was deposited in the right upper bronchi, accidentally discovered after anesthesia when a double-lumen tube was located by fiber bronchoscopy. Following a video-assisted thoracoscopic surgery, the foreign body was removed using a respiratory endoscopy without subsequent adverse consequences for the patient.
Conclusions
There is a risk of complications from iatrogenic airway foreign bodies for preoperative localization of pulmonary nodules by injecting cyanoacrylate glue.
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Dynamic design for high slope treatment for left bank underground power house intake of Longtan hydroelectric project
Cyanoacrylate glue foreign body after CT-guided localization of a pulmonary nodule during video-assisted thoracoscopic surgery: a case report
Abstract Background A tracheal foreign body is a common airway aspiration that creates an emergency, which often causes unobserved respiratory problems and requires management. Iatrogenic tracheal foreign bodies are rarely observed, which results in tracheal obstruction. If the foreign body were removed from the tracheobronchial system, it would save lives. A similar case of a tracheal foreign body was focused on, which was caused by medical glue used during preoperative computed tomography localization of pulmonary nodules. Case presentation The foreign body was deposited in the right upper bronchi, accidentally discovered after anesthesia when a double-lumen tube was located by fiber bronchoscopy. Following a video-assisted thoracoscopic surgery, the foreign body was removed using a respiratory endoscopy without subsequent adverse consequences for the patient. Conclusions There is a risk of complications from iatrogenic airway foreign bodies for preoperative localization of pulmonary nodules by injecting cyanoacrylate glue
Preparation and characterization of temperature-responsive chromatographic column containing poly(N-isopropylacrylamide) and poly([2-(methacryloyloxy)- ethyl]trimetylammonium chloride)
Research on Internal Current Sharing of High-power IGBTs
In order to increase the rating current level of device, high power IGBT is often composed of multiple chips and subelements in parallel, and in this case, how to effectively control the current sharing within device is very important. It analysed the important influence of stray inductance on IGBTs internal current sharing by experimental research, deduced and analyzed theoretically the influence of chip parameters on static current sharing, and verified the influence of chip parameters on dynamic current sharing by experiment and simulation. The results showed that the influence of the asymmetry of the parasitic parameters on current sharing is greater than that of chip parameters, and the influence of both on turning-on current sharing is greater than that of the turning-off
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