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High-voltage spinel cobalt-free LiNi

Electrolyte engineering via fluorinated additives is promising to improve cycling stability and safety of high-energy Li-metal batteries. Here, an electrolyte is reported in a porous lithium fluoride (LiF) strategy to enable efficient carbonate electrolyte engineering for stable and safe Li-metal batteries. Unlike traditionally engineered electrolytes, the prepared electrolyte in the porous LiF nanobox exhibits nonflammability and high electrochemical performance owing to strong interactions between the electrolyte solvent molecules and numerous exposed active LiF (111) crystal planes. Via cryogenic transmission electron microscopy and X-ray photoelectron spectroscopy depth analysis, it is revealed that the electrolyte in active porous LiF nanobox involves the formation of a high-fluorine-content (>30%) solid electrolyte interphase layer, which enables very stable Li-metal anode cycling over one thousand cycles under high current density (4 mA cm-2 ). More importantly, employing the porous LiF nanobox engineered electrolyte, a Li || LiNi0.8 Co0.1 Mn0.1 O2 pouch cell is achieved with a specific energy of 380 Wh kg-1 for stable cycling over 80 cycles, representing the excellent performance of the Li-metal pouch cell using practical carbonate electrolyte. This study provides a new electrolyte engineering strategy for stable and safe Li-metal batteries.

Using highly dispersed metal fluoride nanoparticles to construct a uniform fluorinated alloy type interfacial layer on the surface of Li metal anodes is realized by an ex situ solution chemical modification method. The fluorinated alloy-type interfacial layer can effectively inhibit the growth of undesirable Li dendrites while enhancing the performance of Li metal anodes.

Currently, developing high voltage (beyond 2 V) rechargeable Mg-ion batteries still remains a great challenge owing to the limit of corrosive electrolyte and low compatibility of anode material. Here we report a facile one step solid state alloying route to synthesize nanoclustered Mg3Bi2 alloy as a high-performance anode to build up a 2 V Mg-ion battery using noncorrosive electrolyte. The fabricated nanoclustered Mg3Bi2 anode delivers a high reversible specific capacity (360 mAh g–1) with excellent stability (90.7% capacity retention over 200 cycles) and high Coulombic efficiency (average 98%) at 0.1 A g–1. The good performance is attributed to the stable nanostructures, which effectively accommodate the reversible Mg2+ ion insertion/deinsertion without losing electric contact among clusters. Significantly, the nanoclustered Mg3Bi2 anode can be coupled with high voltage cathode Prussian Blue to assemble a full cell using noncorrosive electrolyte, showing a stable cycling (88% capacity retention over 200 ...

In this study, a novel polyvinylidene fluoride (PVDF) hollow fiber nanocomposite ultrafiltration (UF) hollow fiber membrane was fabricated by introducing titanate nanotubes (TNTs) into the membrane matrix. Prior to membrane fabrication, the properties of TNTs were characterized using TEM, XRD and BET. The effect of TNTs loading (0–1.0%) on the properties of PVDF membrane such as cross section morphology, permeation and rejection capabilities were studied. Characterizations in term of membrane cross section morphology, contact angle and porosity were conducted. PVDF-TNT 0.5% nanocomposite membrane exhibited the most promising results, with colour removal of 58.9%, based on the American Manufacturers Dye Index (ADMI) value. Furthermore, these membranes were able to maintain flux values of 35.8 L/m2h for the duration of 240 min, showing very minimal signs of fouling. Analysis on flux recovery after simple pure water washing of the membranes also showed TNT loaded membranes are resistant towards fouling with 90% flux recovery and >95% rejection recovery rate when membranes were filtered for 5 continuous cycles.

Lithium cobalt oxide (LiCoO2) possesses an attractive theoretical specific capacity (274 mAh g–1) and high discharge voltage (∼4.2 V vs Li+/Li). However, only a half of the theoretical capacity of ...

The commercial ceramic nanoparticle coated microporous polyolefin separators used in lithium batteries are still vulnerable under external impact, which may cause short circuits and consequently severe safety threats, because the protective ceramic nanoparticle coating layers on the separators are intrinsically brittle. Here, a nacre-inspired coating on the separator to improve the impact tolerance of lithium batteries is reported. Instead of a random structured ceramic nanoparticle layer, ion-conductive porous multilayers consisting of highly oriented aragonite platelets are coated on the separator. The nacre-inspired coating can sustain external impact by turning the violent localized stress into lower and more uniform stress due to the platelet sliding. A lithium-metal pouch cell using the aragonite platelet coated separator exhibits good cycling stability under external shock, which is in sharp contrast to the fast short circuit of a lithium-metal pouch cell using a commercial ceramic nanoparticle coated separator.

Currently, developing high voltage (beyond 2 V) rechargeable Mg-ion batteries still remains a great challenge owing to the limit of corrosive electrolyte and low compatibility of anode material. Here we report a facile one step solid state alloying route to synthesize nanoclustered Mg

A super-peer semantic network defines the semantic groups that client peers and their super peers use to connect with each other according to the semantic similarity of shared documents in peers. This will result in a query that can be evaluated locally thus reducing query process time and the amount of communication required to obtain related data. In this study, new algorithms are proposed to arrange shared documents in peers into hierarchical cluster tree structures, and links will be set up to connect semantically related super peers. During query evaluation, only related peers will be searched thus the complexity of computing is significantly reduced. Consideration is also given to automatically deciding the threshold for clustering and the construction and other essential operations for hierarchical cluster trees. The experiment results illustrate the features of the approach developed in this study.

Spermatic cord mobilization is a routine part of inguinal hernia repair, but the method of cord mobilization varies among surgeons. This study establishes an anatomic plane for spermatic cord mobilization. We studied the anatomy of the superficial cremasteric fascia in 105 male patients during herniorrhaphy for primary inguinal hernias. The mean patient age was 44.8 (18–71) years and mean body mass index was 24.1 kg/m2 (21.5–27.1 kg/m2). The two layers of the superficial cremasteric fascia between the spermatic cord and the inguinal falx were incised to mobilize the cord. We found that spermatic cord mobilization during herniorrhaphy can be easily approached through an anatomic plane between the spermatic cord and the conjoined tendon with subsequent division of the superficial cremasteric fascia. None of the patients experienced any hemorrhage or nerve injury during cord mobilization. We found this method to be both safe and easy to learn. Clin. Anat. 25:1074–1079, 2012. © 2012 Wiley Periodicals, Inc.

This theme focuses on representing and reasoning high-level semantic based on concepts and their space relations. As to multimedia data, such as image and video, acquiring, representing and retrieving high-level semantic information has been a confused problem for a long time. Without the support of knowledge database, it is an impossible mission to carry out the simple synonymous retrieval, let alone retrieving the abstract semantic. This paper proposes some algorithms to translate restored concepts and their relations into a Concept Semantic Network, which is visualized by SVG finally. The paper also introduces the method of recording concepts distribution by description logic, which services users with concepts and distribution retrieval.

Endoscopic thyroidectomy (ET) can be performed through the bilateral areolar approach (BAA). A working space (WS) is typically created on the surface of the pectoral fascia in the chest wall and in the subplatysmal space in the neck. There are several limitations of using this WS. The aim of this study was to establish a new WS for ET.A retrospective review was performed on 85 patients with benign thyroid nodules who had undergone ET through a BAA. A WS was created between the anterior and poster layers of the superficial pectoral fascia (SPF) in the chest and underneath the deep layer of the investing layer (IL) in the neck.The time for creating the WS was 7.2 ± 2.1 (range, 5-12) minutes. No hemorrhage occurred during the procedure. Fat liquefaction occurred in 2 patients. Edema of the neck skin flap presented as lack of a suprasternal notch. No skin numbness occurred. No patient required postoperative pain medication. All patients were extremely satisfied with the cosmetic results.This new method of establishing a WS between the two layers of the SPF and underneath the IL is simple and fast, provides good exposure, yields less postoperative pain, and has a lower risk of skin burn.

Super-peer network adopts two-layer based architecture helps to improve the network performance and the search efficiency. While the dynamic maintenance and broadcast routing mechanism of network topology has an important influence on these two properties. Existing network topology structure has some defects, such as complex maintenance and consuming an excessive amount of bandwidth. This paper proposes a new scalable topology structure based on double-loop Petersen graph, and a new super-peer network DLPSPN, which greatly reduces the maintenance complexity and the bandwidth consuming compared with existing super-peer networks. The efficiency of DLPSPN is also verified by theoretical analysis and simulation experiments.