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Background/aims The efficacy and safety of mepolizumab in patients with severe eosinophilic asthma has been evaluated in a global clinical trial programme. This post hoc analysis assesses the efficacy and safety of mepolizumab in Korean patients. Methods Data from Korean patients in the Phase III, placebo-controlled, randomised DREAM (MEA112997/NCT01000506) and MENSA (MEA115588/ NCT01691521) studies were included. Patients ≥ 12 years old with severe eosinophilic asthma received mepolizumab (DREAM: 75, 250 or 750 mg intravenously [IV]; MENSA: 75 mg IV or 100 mg subcutaneously [SC]), or placebo every 4 weeks for 52 weeks (DREAM) or 32 weeks (MENSA). The primary outcome was the rate of clinically significant asthma exacerbations. Secondary outcomes included forced expiratory volume in 1 second (FEV1), Asthma Control Questionnaire (ACQ) and St George's Respiratory Questionnaire (SGRQ) scores (MENSA only). Blood eosinophil counts (BEC) and safety were assessed throughout. Results Reductions in the rate of clinically significant asthma exacerbations were observed with the approved (100 mg SC) and bioequivalent (75 mg IV) doses of mepolizumab in Korean patients who participated in DREAM and MENSA. In MENSA, trends for improvements from baseline at week 32 in pre-bronchodilator FEV1 (75 mg IV group), ACQ-5 and SGRQ scores (in both treatment groups) were seen versus placebo in Korean patients. Incidence of on-treatment adverse events was similar in Korean patients versus non-Korean patients as were observed reductions from baseline in BEC. Conclusions Mepolizumab treatment provided clinical benefits for Korean patients with severe eosinophilic asthma; the safety profile is consistent with the overall population.

Among many types of low-dimensional inorganic nanostructures, nanostructured MnO2 provides unique advantages in designing and synthesizing efficient electrode and catalyst materials for novel energy storage technologies. The low cost, high redox potential, theoretically high energy storage capacity, environmentally friendliness, and rich deposits provide MnO2 nanomaterials with a high level of economic feasibility for various renewable energy-related applications, like electrodes for metal-ion batteries/metal–sulfur batteries/metal–O2 batteries/supercapacitors and electrocatalysts for oxygen evolution/oxygen reduction/CO2 reduction/N2 fixation. In this review, a wide spectrum of the energy-related applications of diverse nanostructured MnO2 materials is systematically surveyed along with versatile synthetic methods of these metal oxides and chemical design strategies to improve their electrochemical functionalities. Future research perspectives for nanostructured MnO2 materials are provided to offer insightful directions for the exploration of next-generation energy storage/conversion systems.

Three-dimensional (3D) carbon nitrides (C3N4) show excellent photocatalytic performance for the hydrogen evolution reaction (HER) under visible light irradiation. 3D C3N4 can be produced by the hig...

Natrium super ionic conductor (NASICON) materials providing attractive properties such as high ionic conductivity and good structural stability are considered as very promising materials for use as electrodes for lithium- and sodium-ion batteries. Herein, a new high-performance electrode material, Li0.5Ni0.5Ti1.5Fe0.5(PO4)3/C, was synthesized via the sol-gel method and was electrochemically tested as an anode for lithium ion batteries, providing enhanced electrochemical performance as a result of nickel substitution into the lithium site in the LiTi2(PO4)3 family of materials. The synthesized material showed good ionic conductivity, excellent structural stability, stable long-term cycling performance, and improved high rate cycling performance compared to LiTi2(PO4)3. The Li0.5Ni0.5Ti1.5Fe0.5(PO4)3/C electrode delivered reversible capacities of about 93 and 68% of its theoretical one at current rates of 0.1 C (6.42 mA·g-1) after 100 cycles and 5 C (320.93 mA·g-1) after 1000 cycles, respectively. Theoretically, three Li+ ions can be inserted into the vacancies of the Li0.5Ni0.5Ti1.5Fe0.5(PO4)3/C structure. However, when the electrode is discharged to 0.5 V, more than three Li+ ions are inserted into the NASICON structure, leading to its structural transformation, and thus to an irreversible electrochemical behavior after the first discharge process.

The hybridization of conductive nanospecies has garnered significant research interest because of its high efficacy in improving the diverse functionalities of nanostructured materials. In this study, a novel synthetic strategy is developed to optimize the defect structure, structural ordering, and energy‐related functionality of nanostructured‐materials by employing a multilayer multicomponent two‐dimenstional (2D) graphene/metal oxide/graphene nanosheet (NS) as a versatile hybridization matrix. The hybridization of the robust trilayer, polydiallyldiammonium (PDDA)‐anchored reduced‐graphene oxide (prGO)/metal oxide/prGO NS effectively enhance the structural ordering and porosity of the hybridized MoS2/MnO2 NS through suppression of defect formation and tight stacking. In comparison with monolayer rGO/RuO2 NS‐based homologs, the 2D superlattice trilayer prGO/RuO2/prGO NS hybrids deliver better functionalities as a hydrogen evolution electrocatalyst and as a supercapacitor electrode, demonstrating the merits of hybridization with multilayer NSs. The advantages of using multilayer multicomponent conductive NSs as hybridization matrices arise from the enhancement of charge and mass transport through the layer flattening or defect suppression of the hybridized NSs and the increase in porosity, as evidenced by density functional theory calculations. Finally, the universal utility of multilayer NSs is confirmed by investigating the strong effect of the stacking order on the electrocatalytic functionality of MoS2/rGO/RuO2 films fabricated through layer‐by‐layer deposition., A new concept of synthetic strategy to improve various energy functionalities and mass/charge transports of nanostructured materials is developed by employing multilayer conductive graphene/inorganic/graphene nanosheet (NS) as an emerging versatile hybridization matrix. The universal usefulness of hybridization with multilayer multicomponent NSs in exploring high‐performance functional materials originates from optimization of the defect structure, structural ordering, and porosity of hybridized species.

Ni0.5 Ti2 (PO4 )3 /C NASICON-type phosphate is introduced as a new anode material for lithium-ion batteries (LIBs). Ni0.5 Ti2 (PO4 )3 /C was synthesized through the sol-gel route and delivered some remarkable electrochemical performances. Specifically, the Ni0.5 Ti2 (PO4 )3 /C electrode demonstrates a high rate capability performance and delivers high reversible capacities ranging from 130 mAh g-1 to about 111 mAh g-1 at current rates ranging from 0.1 C to 5 C in the voltage window of 1.85-3 V (vs. Li+ /Li). In the same voltage range, the material reaches an initial capacity of 105 mAh g-1 with a capacity retention of about 82 % after 1000 cycles at the high current rate of 10 C. The electrodes are also tested in the wider voltage range of 0.5-3 V (vs. Li+ /Li) and show good reversibility and rate capability performance. Moreover, the Ni0.5 Ti2 (PO4 )3 /C electrodes enable fast Li+ diffusion (in the order of 10-13 cm2 s-1 ) compared with other NASICON-type materials. As a result, a first discharge capacity of 480 mAh g-1 is reached.

A gas chromatography-electron ionization-tandem mass spectrometric (GC-EI-MS/MS) method was developed and validated for determination of the major metabolites of zolpidem, zolpidem phenyl-4-carboxylic acid (ZPCA) and zolpidem 6-carboxylic acid (ZCA) in human hair. The sample preparation procedure involves decontamination, mechanical pulverization, incubation, extraction and purification prior to instrumental analysis. The extracts were derivatized using hexafluoroisopropanol and heptafluorobutyric anhydride and analyzed by GC-EI-MS/MS. The linear ranges were 8-100 pg/mg for ZPCA and 16-200 pg/mg for ZCA, with the correlation coefficients >0.997. The limits of detection were 1.8 pg/mg for ZPCA and 1.7 pg/mg for ZCA. The recoveries ranged from 77.6 to 111.7%. The intra- and inter-day precisions were within 16.9 and 11.7%, while intra- and inter-day accuracies were -7.0-8.7 and -2.8-7.8%, respectively. The developed method was applied for the analysis of forensic hair samples obtained from suspected zolpidem abusers and the following concentration ranges were monitored: ZPCA 11.9-35.9 pg/mg and ZCA 16.6-21.8 pg/mg. The method proved to be suitable for picogram-level determination of ZPCA and ZCA in human hair.

2D nanostructured materials, including inorganic and graphene nanosheets, have evoked plenty of scientific research activity due to their intriguing properties and excellent functionalities. The complementary advantages and common 2D crystal shapes of inorganic and graphene nanosheets render their homogenous mixtures powerful building blocks for novel high-performance functional hybrid materials. The nanometer-level thickness of 2D inorganic/graphene nanosheets allows the achievement of unusually strong electronic couplings between sheets, leading to a remarkable improvement in preexisting functionalities and the creation of unexpected properties. The synergetic merits of atomically coupled 2D inorganic-graphene nanosheets are presented here in the exploration of novel heterogeneous functional materials, with an emphasis on their critical roles as hybridization building blocks, interstratified sheets, additives, substrates, and deposited monolayers. The great flexibility and controllability of the elemental compositions, defect structures, and surface natures of inorganic-graphene nanosheets provide valuable opportunities for exploring high-performance nanohybrids applicable as electrodes for supercapacitors and rechargeable batteries, electrocatalysts, photocatalysts, and water purification agents, to give some examples. An outlook on future research perspectives for the exploitation of emerging 2D nanosheet-based hybrid materials is also presented along with novel synthetic strategies to maximize the synergetic advantage of atomically mixed 2D inorganic-graphene nanosheets.

The huge volume expansion in Sn-based alloy anode materials (up to 360%) leads to a dramatic mechanical stress and breaking of particles, resulting in the loss of conductivity and thereby capacity fading. To overcome this issue, SnO2@C nano-rattle composites based on &lt, 10 nm SnO2 nanoparticles in and on porous amorphous carbon spheres were synthesized using a silica template and tin melting diffusion method. Such SnO2@C nano-rattle composite electrodes provided two electrochemical processes: a partially reversible process of the SnO2 reduction to metallic Sn at 0.8 V vs. Li+/Li and a reversible process of alloying/dealloying of LixSny at 0.5 V vs. Li+/Li. Good performance could be achieved by controlling the particle sizes of SnO2 and carbon, the pore size of carbon, and the distribution of SnO2 nanoparticles on the carbon shells. Finally, the areal capacity of SnO2@C prepared by the melt diffusion process was increased due to the higher loading of SnO2 nanoparticles into the hollow carbon spheres, as compared with Sn impregnation by a reducing agent.

Natrium super ionic conductor (NASICON) materials providing attractive properties such as high ionic conductivity and good structural stability are considered as very promising materials for use as electrodes for lithium- and sodium-ion batteries. Herein, a new high-performance electrode material, Li

A novel, rational, and efficient way to explore high-performance electrocatalysts was developed by controlling the reaction kinetics of the rate-determining step (RDS). Density functional theory (DFT) calculations demonstrate that the RDS for the oxygen evolution reaction driven by transition metal hydroxides/oxides, i.e., surface adsorption of OH−/OOH• species, can be significantly promoted by increasing the electrophilicity of electrocatalysts via hybridization with electron-withdrawing inorganic nanosheets. As predicted by DFT calculation, the hybridization of Ni–Fe-layered double hydroxide (LDH)/Ni–Co-LDH, with RuO2 nanosheets (1.0 wt%) leads to significant lowering of the overpotentials to 207/276 mV at 10 mA cm−2, i.e., one of the smallest overpotentials for LDH-based materials, with the increase in the current density. The necessity of a very small amount of RuO2 nanosheets (1.0 wt%) to optimize the electrocatalyst activity highlights the remarkably high efficiency of the RuO2 addition. The present study underscores the importance of kinetic control of the RDS via hybridization with electron-withdrawing species for exploring novel efficient electrocatalysts. Platinum and other precious metals currently used in fuel cells may ultimately be replaced by nanostructured catalysts designed with the help of computers. Catalysts are essential for speeding up the oxygen evolution reaction in fuel cells, a normally slow extraction of electrons and protons from water molecules. A team led by Hyungjun Kim from the Korea Advanced Institute of Science and Technology in Daejon and Seong-Ju Hwang from Ewha Womans University in Seoul have now used computer simulations to optimize inexpensive oxygen evolution catalysts made from transition metal hydroxides. Their calculations predicted that these normally multilayered catalysts could split water faster if exfoliated into individual sheets and attached to a ruthenium nanostructure. Fabrication of these materials revealed they had significantly higher active surface areas and improved energy efficiency compared to typical metal hydroxide catalysts. A rational way to explore economically feasible high-performance electrocatalyst for OER is developed by improving the reaction kinetics of rate-determining step via the hybridization with electron-withdrawing RuO2 nanosheet. Even with very low RuO2 content, self-assembled Ni–Fe-/Ni–Co-layered double hydroxide (LDH)–RuO2 nanohybrids show very small overpotentials of 207/276 mV at 10 mA cm−2 for oxygen evolution reaction with greatly improved current densities.

Efficient visible light active hybrid photocatalysts for H2 production can be synthesized by the intercalative hybridization of Zn-Cr-layered double hydroxide (Zn-Cr-LDH) with a mesoporous g-C3N4 lattice. Small Zn-Cr-LDH nanocrystals with a size of ∼6 nm are immobilized in the mesopores of g-C3N4. Beyond an optimal LDH/g-C3N4 molar ratio of 0.3, a further increase in the LDH content leads to the surface deposition of LDH crystals on the g-C3N4 material as well as the intercalative immobilization of LDH into its mesopores, indicating the controllability of the LDH deposition site. The Zn-Cr-LDH-g-C3N4 nanohybrids exhibit smaller surface areas than the pristine g-C3N4, confirming the intercalative stabilization of Zn-Cr-LDH nanocrystals in the mesopore of g-C3N4. The hybridization between Zn-Cr-LDH and g-C3N4 is effective in enhancing visible light absorptivity and also in depressing electron-hole recombination, which is attributable to an efficient electronic coupling between both the hybridized components. The present Zn-Cr-LDH-g-C3N4 nanohybrid exhibits promising photocatalytic activities for visible light-induced H2 production at a rate of 155.7 μmol g-1 h-1, which is much superior to that of the pristine g-C3N4 (21.7 μmol g-1 h-1). The present study underscores that the intercalative immobilization of Zn-Cr-LDH crystals in the limited space of a mesopore is quite useful in improving the visible light active photocatalyst functionality of mesoporous carbon nitride.

Ni

Sample preparation is an important step in the isolation of target compounds from complex matrices to perform their reliable and accurate analysis. Hair samples are commonly pulverized or processed as fine cut, depending on preference, before extraction by techniques such as solid-phase extraction (SPE), liquid&ndash, liquid extraction, and other methods. In this study, a method based on hybrid solid-phase extraction (hybridSPE) and gas chromatography&ndash, mass spectrometry (GC&ndash, MS) was developed and validated for the determination of methamphetamine (MA) and amphetamine (AP) in hair. The hair samples were mechanically pulverized after washing with de-ionized water and acetone. The samples were then sonicated in methanol at 50 &deg, C for 1 h and centrifuged at 50,000&times, g for 3 min. The supernatants were transferred onto the hybridSPE cartridge and extracted using 1 mL of 0.05 M methanolic hydrogen chloride. The combined solutions were evaporated to dryness, derivatized using pentafluoropropionic anhydride, and analyzed by GC&ndash, MS. Excellent linearity (R2 &gt, 0.9998) was achieved in the ranges of 0.05&ndash, 5.0 ng/mg for AP and 0.1&ndash, 10.0 ng/mg for MA. The recovery was 83.4&ndash, 96.8%. The intra- and inter-day accuracies were &minus, 9.4% to 5.5% and &minus, 5.1% to 3.1%, while the intra- and inter-day precisions were within 8.3% and 6.7%, respectively. The limits of detections were 0.016 ng/mg for AP and 0.031 ng/mg for MA. The validated hybridSPE method was applied to dyed hair for MA and AP extraction and compared to a methanol extraction method currently being used in our laboratory. The results showed that an additional hybridSPE step improved the recovery by 5.7% for low-concentration quality control (QC) samples and by 24.1% for high-concentration QC samples. Additionally, the hybridSPE method was compared to polymeric reversed-phase SPE methods, and the absolute recoveries for hybridSPE were 50% and 20% greater for AP (1.5 ng/mg) and MA (3.0 ng/mg), respectively. In short, the hybridSPE technique was shown to minimize the matrix effects, improving GC&ndash, MS analysis of hair. Based on the results, the proposed method proved to be effective for the selective determination of MA and AP in hair samples.

Although urine and blood samples have been conventionally used for testing zolpidem (ZPD), a sedative-hypnotic, these matrices have limited application because they have a relatively short detection period and can be used only in case of recent drug exposure. Therefore, it is necessary to use an alternative biological sample to obtain the evidence of ZPD misuse. Herein, a liquid chromatography–tandem mass spectrometric (LC–MS/MS) method was developed for the determination of ZPD and its metabolites, zolpidem phenyl-4-carboxylic acid (ZPCA) and zolpidem 6-carboxylic acid (ZCA), in hair to resolve the above-mentioned problems. Mechanical pulverization of hair, methanol extraction with sonication, and the zirconia-based hybrid solid–phase extraction technique were used for obtaining improved extraction efficiency and effective sample purification. The treated hair sample was analyzed using the LC–MS/MS method with the electrospray ionization source in positive and multiple-reaction monitoring modes. The target analytes were separated and detected within 8 min using an Xselect HSS T3 column. Gradient elution was performed using 5 mM ammonium formate and acetonitrile. The lower limit of quantification of ZPD, ZPCA, and ZCA were 1.0, 0.5, and 1.0 pg mg−1, respectively. The calibration ranges were 1.0–1000.0 pg mg−1 for ZPD, 0.5–200.0 pg mg−1 for ZPCA, and 1.0–200.0 pg mg−1 for ZCA, with the determination coefficients (r2 ≥ 0.9986). The intraday accuracy and precision ranged from −7.1 to 9.0% and within 6.5%, respectively, and the interday accuracy and precision ranged from −6.1 to 7.9% and within 5.4%, respectively. The recovery, matrix effect, and process efficiency were 65.2–96.6%, 64.6–106.5%, and 44.3–100.5%, respectively, with the relative standard deviation of 4.0–5.0%. The developed method was successfully applied to analyze 13 forensic hair samples of ZPD abusers, and the concentration ratios of ZPD and its two main metabolites (ZPCA and ZCA) in the ZPD-positive samples were also presented. These results revealed that ZPCA and ZCA were not easily incorporated into hair, and demonstrated that their analysis in hair samples requires the employed method to have picogram-level sensitivity. Therefore, the developed method was suitable for simultaneous analysis of ZPD, ZPCA, and ZCA in hair samples, and it could provide clear evidence for illegal ZPD administration, including ZPD-facilitated sexual assault.

The effect of the catalyst morphology on the growth of carbon nanotubes (CNT) on nanostructured transition metal oxides was investigated to study a novel low-temperature synthetic route to functional CNT–transition metal oxide nanocomposites. Among several nanostructured manganese oxides with various morphologies and structures, only exfoliated 2D nanosheets of layered MnO2 acted as an effective catalyst for the chemical vapor deposition of CNT at low temperatures of 400–500 °C, which emphasizes the critical role of the catalyst morphology in CNT growth. Heat treatment of the MnO2 nanosheets under a C2H2 flow induced the deposition of CNT, as well as a phase transition to a 2D ordered assembly of MnO nanoparticles. The resulting CNT–MnO nanocomposites displayed excellent functionalities in Li-ion electrodes with huge discharge capacities and good rate characteristics, which highlights the usefulness of the present method for studying functional CNT–metal oxide nanocomposites. Electron microscopy and density functional theory calculations propose a formation mechanism via the efficient adsorption of carbon on the MnO2 nanosheets followed by the surface diffusion of carbon. It is of prime importance that the substitution of Fe for layered MnO2 nanosheets remarkably improved the efficiency of the formation of CNT by enhancing the surface adsorption of carbon species. This is the first report of the efficient growth of CNT at a very low temperature of 400 °C. The universal merit of the 2D nanosheet morphology was confirmed by the successful synthesis of a CNT–TiO2 nanocomposite with exfoliated titanate nanosheets. The present study demonstrates that employing exfoliated transition metal oxide nanosheets as catalysts provides an efficient low-temperature synthetic route to functional CNT–transition metal oxide nanocomposites.

Efficient inorganic nanosheet-based electrode materials can be synthesized by the calcination of exfoliated Ti 5 NbO 14 nanosheets under C 2 H 2 flow. While the calcination in Ar atmosphere causes a phase transformation from layered Ti 5 NbO 14 to TiO 2 and Nb 2 O 5 , employing C 2 H 2 atmosphere leads to the maintenance of the original layered structure of Ti 5 NbO 14 upon the heat-treatment, which is attributable to the stabilization of layered lattice by surface passivation by deposited carbon layer. The resulting carbon@titanoniobate materials show mesoporous house-of-cards-type stacking structure of 2D nanosheets. This carbon@titanoniobate material delivers large discharge capacity of ~320 mA h g −1 with excellent cyclability and rate performance, which is much superior to that of carbon-free homologue. The present study clearly demonstrates that the heat-treatment under C 2 H 2 flow provides a simple and effective route to high-performance inorganic nanosheet-based electrode materials.

A rapid synthetic route to nanocrystalline carbon-incorporated mixed metal oxide nanocomposites with enhanced electrode performance for lithium ion batteries is developed by applying a very short heat-treatment of layered double hydroxide (LDH) precursor under C2H2 flow. Employing C2H2 atmosphere makes possible the rapid synthesis of nanocrystalline C–NiO–NiFe2O4 nanocomposite via the calcination of the Ni–Fe–LDH precursor at 300 °C in a very short period of 5 min. In the case of ambient atmosphere, a prolonged calcination time of several hours is demanded to induce a complete phase transformation from Ni–Fe–LDH to electrochemically active NiO–NiFe2O4 nanocomposite, highlighting the usefulness of C2H2 atmosphere in promoting the formation of mixed metal oxide nanocomposite. The present C–NiO–NiFe2O4 nanocomposite shows much better anode performance for lithium ion batteries with greater discharge capacity and better cyclability than do the NiO–NiFe2O4 nanocomposites prepared by the prolonged calcination o...

New class of superlattice nanohybrids of interstratified graphitic-carbon nitride (g-C3N4)–transition metal dichalcogenide monolayers are synthesized by employing pH-controlled g-C3N4 nanosheet (NS) as an emerging cationic building block. The interstratification of g-C3N4 and MoS2 NSs leads to strong interfacial electronic coupling, creation of nitrogen vacancy, and stabilization of 1T′-MoS2 phase. The superlattice g-C3N4–MoS2 nanohybrids display remarkably enhanced bifunctionality as photocatalysts for visible light-induced N2 fixation and electrocatalysts for hydrogen evolution. Of prime importance is that the creation of nitrogen vacancy results in the significant improvement of selectivity for photocatalytic N2 fixation (582 μmolL−1h−1) over competitive photocatalytic H2 generation. This is attributable to promoted adsorption of nitrogen, provision of many active sites, and enhancement of charge transfer kinetics, charge separation, and visible light absorptivity. This study highlights that the application of g-C3N4 NS as a cationic building block provides valuable opportunity to widen the library of multifunctional NS-based superlattice nanohybrids.

Here we report the first study on the electrochemical energy storage application of a surface-immobilized ruthenium complex multilayer thin film with anion storage capability. We employed a novel dinuclear ruthenium complex with tetrapodal anchoring groups to build well-ordered redox-active multilayer coatings on an indium tin oxide (ITO) surface using a layer-by-layer self-assembly process. Cyclic voltammetry (CV), UV-Visible (UV-Vis) and Raman spectroscopy showed a linear increase of peak current, absorbance and Raman intensities, respectively with the number of layers. These results indicate the formation of well-ordered multilayers of the ruthenium complex on ITO, which is further supported by the X-ray photoelectron spectroscopy analysis. The thickness of the layers can be controlled with nanometer precision. In particular, the thickest layer studied (65 molecular layers and approx. 120 nm thick) demonstrated fast electrochemical oxidation/reduction, indicating a very low attenuation of the charge transfer within the multilayer. In situ-UV-Vis and resonance Raman spectroscopy results demonstrated the reversible electrochromic/redox behavior of the ruthenium complex multilayered films on ITO with respect to the electrode potential, which is an ideal prerequisite for e.g. smart electrochemical energy storage applications. Galvanostatic charge-discharge experiments demonstrated a pseudocapacitor behavior of the multilayer film with a good specific capacitance of 92.2 F g(-1) at a current density of 10 μA cm(-2) and an excellent cycling stability. As demonstrated in our prototypical experiments, the fine control of physicochemical properties at nanometer scale, relatively good stability of layers under ambient conditions makes the multilayer coatings of this type an excellent material for e.g. electrochemical energy storage, as interlayers in inverted bulk heterojunction solar cell applications and as functional components in molecular electronics applications.

Nanoparticles of LiMnPO4 were fabricated in rod, elongated as well as cubic shapes. The 1D Li+ preferred diffusion direction for each shape was determined via electron diffraction spot patterns. The shape of nano-LiMnPO4 varied the diffusion coefficient of Li+ because the Li+ diffusion direction and the path length were different. The particles with the shortest dimension along the b-axis provided the highest diffusion coefficient, resulting in the highest gravimetric capacity of 135, 100 and 60 mAh g−1 at 0.05C, 1C and 10C, respectively. Using ball-milling, a higher loading of nano-LiMnPO4 in the electrode was achieved, increasing the volumetric capacity to 263 mAh cm−3, which is ca. 3.5 times higher than the one obtained by hand-mixing of electrode materials. Thus, the electrochemical performance is governed by both the diffusion coefficient of Li+, which is dependent on the shape of LiMnPO4 nanoparticles and the secondary composite structure.

Cathodes in lithium ion batteries consist of an ionic conductor, an electronic conductor and a binder in order to make a composite that is both electronically and ionically conductive. The carbon coating on the cathode material plays a critical role for the electrochemical properties of lithium ion batteries due to the increased electronic conductivity. We explain the relationship between the electrochemical properties and the characteristics of composites prepared using the ball-milling process in this report. We investigated two types of carbonaceous materials (graphite and carbon black) in LiCoO₂ electrodes. These selected carbon materials have different characteristics and structure upon ball-milling with LiCoO₂. The composite prepared by ball-milling for 5 min leads to better mixing of carbon and LiCoO₂, an intimate contact of carbon on LiCoO₂, a higher lithium ion diffusion (DLi) than non ball-milled and longer ball-milled composites. On the other hand, a longer time of ball-milling (30 and 60 min) decreases the electronic and ionic conductivity due to an increase of disordered structure of carbon and a thick and dense carbon coating layer on LiCoO₂ particles, preventing the diffusion of lithium ions, respectively.

Conductive carbon coatings on cathode materials play a critical role in the electrochemical performance of lithium ion batteries due to the increased electronic conductivity and the protective effect of the organic electrolyte on the cathode material. The composite structure of a cathode depends on the physicochemical properties of the carbonaceous materials. We investigated several types of carbonaceous materials in LiCoO2 electrodes. Platelet-shaped graphite provided superior cyclic voltammograms and specific capacities of the LiCoO2 electrodes compared to nanosized spherical carbon black. The platelet-shaped graphite mixed homogeneously with LiCoO2 and coated on LiCoO2 particles in the form of a thin layer via the ball-milling method. However, the nano-carbon black is dense and aggregates during the ball-milling process. The thick coating of nano-carbon black on the LiCoO2 particles, which were observed in backscattered electron images collected during the SEM measurements, made the penetration of the liquid electrolyte through this thick carbon layer difficult.

Background LiCoO2 is one of the most used cathode materials in Li-ion batteries. Its conventional synthesis requires high temperature (>800 °C) and long heating time (>24 h) to obtain the micronscale rhombohedral layered high-temperature phase of LiCoO2 (HT-LCO). Nanoscale HT-LCO is of interest to improve the battery performance as the lithium (Li+) ion pathway is expected to be shorter in nanoparticles as compared to micron sized ones. Since batteries typically get recycled, the exposure to nanoparticles during this process needs to be evaluated. Results Several new single source precursors containing lithium (Li+) and cobalt (Co2+) ions, based on alkoxides and aryloxides have been structurally characterized and were thermally transformed into nanoscale HT-LCO at 450 °C within few hours. The size of the nanoparticles depends on the precursor, determining the electrochemical performance. The Li-ion diffusion coefficients of our LiCoO2 nanoparticles improved at least by a factor of 10 compared to commercial one, while showing good reversibility upon charging and discharging. The hazard of occupational exposure to nanoparticles during battery recycling was investigated with an in vitro multicellular lung model. Conclusions Our heterobimetallic single source precursors allow to dramatically reduce the production temperature and time for HT-LCO. The obtained nanoparticles of LiCoO2 have faster kinetics for Li+ insertion/extraction compared to microparticles. Overall, nano-sized LiCoO2 particles indicate a lower cytotoxic and (pro-)inflammogenic potential in vitro compared to their micron-sized counterparts. However, nanoparticles aggregate in air and behave partially like microparticles. Electronic supplementary material The online version of this article (doi:10.1186/s12951-017-0292-3) contains supplementary material, which is available to authorized users.

5–10 nm thin rod shaped LiMnPO 4 nanoparticles are synthesized by an improved thermal decomposition method. The synthesis parameters such as the concentration of surfactants, reaction temperature and time, as well as the presence of a solvent play a critical role in the formation of spherical, thin or thick nanorods, and needle-shaped particles of LiMnPO 4 . A washing procedure to efficiently eliminate the surfactants attached to the surface of LiMnPO 4 nanoparticles is presented, avoiding thermal treatment at high temperatures. A nanocomposite LiMnPO 4 electrode provides a discharge capacity of 165 mAh/g at 1/40 C and 66 mAh/g at 1 C with only 10 wt% of total carbon additive. The characteristics of as-synthesized and low amount of carbon coated LiMnPO 4 are described as well as their electrochemical properties.

Fabric construction affects the friction between yarns, which is a very important parameter on energy absorption and propagation. This study reports the physical properties dependent on the weaving density and STF (shear thickening fluid) impregnated aramid fabrics. To improve the frictional force between yarns, STF was applied on Kevlar woven fabrics. STF/Kevlar composite was composed of Kevlar woven fabrics impregnated with fumed silica dispersed in poly-ethylene glycol. The results demonstrated that the yarn pull-out force of neat Kevlar fabrics increased linearly as the fabric count increased. In the case regarding STF impregnated Kevlar fabrics, the pull-out force increased exponentially as the fabric count increased. Considering the ballistic performance of the fabric is related to the pull-out force of yarns in the fabric, the STF/Kevlar composite with high density woven fabrics can be a decent material for bullet-proof equipment.

In [1], Maffei proved a certain relationship between quiver varieties of type A and the geometry of partial ag varieties over the nilpotent cone. This relation was conjectured by Nakajima, and Nakajima proved his conjecture for a simple case. In the Maffei`s proof, the key step was a reduction of the general case of the conjecture to the simple case treated by Nakajima through a certain isomorphism. In this paper, we study properties of this isomorphism.

A novel polyol synthesis was adopted to synthesize nano-structured LiMnPO4. This route yields well-crystallized nanoparticles with platelet morphology that are only similar to 30 nm thick oriented in the b direction. The obtained material presented a good rate behavior and a very long cyclic life both at room temperature (RT) and 50 degrees C. The sample exhibited a specific capacity of 145 mAh g(-1) at C/20, 141 mAh g(-1) at C/10 rate and 113 mAh g(-1) 1C rate. This represents is the highest performance results reported to date for this material. The high rate performance is ascribed to the platelet shape of the LiMnPO4 as it minimizes the paths for Li diffusion. At elevated temperature (50 degrees C) this material demonstrated improved reversible capacity of 159 mAh g(-1) at C/10 and 138 at 1C. The electrode retained 95% of its capacity, over 200 cycles, both at RT and 50 degrees C. This electrochemical stability is ascribed to the structural strength of the P-O bond and the stability of the electrolyte-LiMnPO4 interface. It allows us to conclude that the impact of a possible Jahn-Teller distortion is not critical. These excellent results clarified some ambiguities on LiMnPO4 as cathode materials. and demonstrate its promise for its practical application. (C) 2008 Elsevier B.V. All rights reserved.

Conclusion. There is high prevalence of lower airway diseases in patients with chronic rhinosinusitis and frequently co-existing lower airway diseases have not been diagnosed before. Objectives. To examine the prevalence of lower airway diseases in patients with chronic rhinosinusitis. Methods. Seventy-three consecutive patients with chronic rhinosinusitis were enrolled in this prospective study. With routine physical examination, spirometry and methacholine bronchial provocation test were performed and chest simple radiograph or chest computed tomography was taken. Results. Thirty patients (41.1%) had lower airway diseases. There were 8 patients with asthma, 5 with asymptomatic bronchial hyperresponsiveness, 11 with small airway disease, 2 with chronic obstructive pulmonary disease and 4 with bronchiectasis. Of these 30 patients, 21 patients (70.0%) were first diagnosed as having lower airway diseases in this study.

The aim of this study was to describe the CT and sonographic findings of hepatic visceral larva migrans of Toxocara canis.Fifty-four patients (44 men, 10 women; age range, 30-80 years; mean age, 53 years) with serologically confirmed visceral larva migrans of Toxocara canis underwent evaluation of the liver with CT (n = 25), sonography (n = 48), or both. Two radiologists used consensus for retrospective evaluation of CT and sonographic findings. Correlation between the presence and severity of hepatic abnormalities on images and the degree of peripheral eosinophilia was assessed.Seventeen (68%) of 25 patients who underwent CT had single or multiple ill-defined, oval or elongated, small, low-attenuating lesions in the liver. Eighteen (38%) of 48 patients who underwent sonography had single or multiple small, poorly defined, oval or elongated, hypoechoic scattered focal lesions in the liver. In the 19 patients who underwent both CT and sonography, the two techniques had no significant difference in rate of detection of hepatic lesions (p = 0.375, McNemar test). The lesion numbers on CT and sonography showed excellent linear correlation (r = 0.844, p = 0.001) by Pearson's correlation test. An independent samples t test showed that eosinophil count and percentage in the peripheral blood were significantly higher in patients with hepatic lesions on CT and sonography than in patients without lesions.CT and sonographic findings of hepatic visceral larva migrans of T. canis are multiple, ill-defined, oval or elongated, small, nodular lesions scattered in the liver parenchyma. The presence of hepatic lesions on images was associated with higher peripheral eosinophil count and percentage.

Cough lasting3 weeks has been defined as chronic cough. However, it might be more persuasive to divide cough into subacute, lasting 3 to 8 weeks, and chronic, lasting8 weeks. We evaluated the causes and clinical courses of subacute cough, and the value of the bronchoprovocation test and induced sputum examination (IS).Nonsmoking patients with cough of 3 to 8 weeks duration were enrolled into the study. Patients with dyspnea, basal FEV1 of70% predicted, abnormal findings on a plain chest radiograph or physical examination were excluded. We prescribed an antihistamine-decongestant for patients who were suspected to have postinfectious cough or postnasal drip. If patients had positive results on a bronchoprovocation test or IS, therapy with inhaled corticosteroids was substituted according to an algorithmic approach.One hundred eighty-four patients (77 men and 107 women) were evaluated; the mean age of the study group was 47.5 years. Eighty-nine of 184 patients had postinfectious cough. Cough resolved without treatment in 62 patients. Twenty-nine of 43 patients with positive bronchoprovocation test results had cough-variant asthma.Postinfectious cough was the most common cause of subacute cough. The spontaneous resolution of cough was frequent in patients with subacute cough. Unless asthma was strongly suspected, the performance of the bronchoprovocation test could be delayed until after empirical treatment had been administered.

Churg-Strauss syndrome (CSS) is a rare multi-system vasculitis; some cases have been reported in Korea. The aim of this study is to describe the clinical features, treatment outcome, and long-term follow-up of CSS from a single Korean medical center. Between 1995 and 2004, seventeen patients were diagnosed with CSS at the Department of Medicine of the Samsung Medical Center, Sungkyunkwan University School of Medicine. The diagnosis of CSS is based on the classification criteria of the American Collage of Rheumatology. All patients had asthma. As in other case series, the lung, peripheral nervous system, and skin were the most commonly involved organs. During the active stage of the disease, most of the patients exhibited peripheral blood eosinophilia and an elevated serum eosinophil cationic protein level. Ten patients were treated with pulses of methylprednisolone followed by tapering and cyclophosphamide, and the others were treated with corticosteroids alone. The outcomes after long-term follow-up were generally good. One patient who was refractory to initial treatment died of heart failure during the follow-up period. CSS was highly variable in its presentation and course. The manifestations may range from mild symptoms to life-threatening conditions. The outcome after long-term follow-up was as good as that of previous studies.

Toxocariasis is one of the causes of eosinophilia in peripheral blood and provokes eosinophilic infiltration in internal organs. Extended studies on the prevalence and clinical characteristics of toxocariasis have been rare. The aim of this study is to evaluate the prevalence of toxocariasis in unknown eosinophilia and to analyze the efficacy of toxocara enzyme-linked immunosorbent assay (ELISA). We evaluated patients presenting with peripheral blood eosinophilia (500 cells/microl oror =10% of white blood cell count). After checking drug histories and the presence of allergic diseases and parasitic infections, specific serum IgG antibody to Toxocara canis larval antigen was measured by ELISA. Liver and lung involvement was also evaluated. One-hundred and three patients were evaluated, and the mean age was 50.9 years old. Seventy patients (68.0%) were diagnosed as having toxocariasis. The patients who had a history of raw liver eating had a higher incidence, and the patients with liver involvement had higher serum eosinophil cationic protein values. The eosinophil count was normalized in 7 of 16 treated patients and in 25 of 54 untreated patients. The mean improvement duration was 12 months. We concluded that the prevalence of toxocariasis was high in patients with unknown eosinophilia, and the toxocara ELISA was essential for evaluation of the causes of unknown eosinophilia.

To fabricate a reliable device using Cu interconnect technology, it is important to form an initial pattern profile with a good sidewall surface roughness at via bottom due to barrier step coverage issues. However, if Ar sputter etch clean is used at via contact clean prior to barrier deposition, this induces a Cu redeposition on the via sidewall. This redeposited Cu can lead to the degradation by sidewall morphology and finally the reliability issues due to poor barrier step coverage. In this study, we evaluate the reactive preclean process (RPC) as an alternative technology to overcome the disadvantages of sputter clean and discuss the effectiveness of RPC on the removal of Cu oxide in Cu dual damascene interconnect.