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Although genetic Creutzfeldt-Jakob disease (CJD) is a rare neurodegenerative disorder, cases of genetic CJD with E200K mutation are being increasingly reported in Korea. However, the clinical features and course of genetic CJD with E200K mutation in Korea remain unclear. We describe the clinical features and course of genetic CJD with E200K mutation in a patient who initially presented with rapid progressive memory impairment and myoclonus.

A 48-year-old woman presented with a 1-day history of aggressive behavior. Hashimoto encephalopathy was first suspected based on elevated levels of serum anti-thyroid peroxidase antibody. Her clinical symptoms did not improve despite treatment with intravenous corticosteroid. Abdominal computed tomography revealed liver cirrhosis, and brain T2-weighted magnetic resonance imaging revealed midbrain hyperintensity, and she was finally diagnosed with Wilson’s disease. The Wilson’s disease should be considered in the differential diagnosis in adults presenting with unexplained hepatic, neurological, or psychiatric abnormalities.

Submicron and micron-sized carbon spheres with high electrical conductivity, micro–mesoporous structure, and empty space are considered ideal sulfur host materials for Li–S batteries. In this study, a new and efficient strategy for the synthesis of yolk-shell-structured carbon microspheres with multishells is introduced. Pitch-derived carbon microspheres with yolk-shell structure, high pore volume, and high electrical conductivity are synthesized by applying yolk-shell-structured Fe2O3 microspheres as a sacrificial template. Pitch-infiltrated Fe2O3 microspheres transform into yolk-shell-structured carbon (YS_C) microspheres with a specific conductivity of 0.9 S cm−1 after post-treatment and etching with an HCl solution. The discharge capacity of the sulfur-loaded YS_C microspheres for the 200th cycle at a current density of 0.5 C is 686 mA h g−1, and their reversible capacity after 800 cycles at a high current density of 2 C is 412 mA h g−1. In addition, the sulfur-loaded YS_C microspheres show excellent cycling performance, despite their very high sulfur loading of 70 wt%. The excellent cycling and rate performances of the sulfur-loaded YS_C microspheres are attributed to the synergistic effect of the high electrical conductivity of YS_C microspheres, loading of amorphous and ultrafine sulfur, and empty shell layers.

SnO2-based composite materials have been studied as efficient anode materials for lithium-ion batteries. In this study, pitch-derived carbon coated SnO2–CoO yolk–shell microspheres were synthesized by a spray drying process. Pitch is a widely used source material for electrically conductive carbon. Pitch-infiltrated SnO2–Co3O4 were transformed into SnO2–CoO–C yolk–shell microspheres by a carbothermal reduction. SnO2–CoO–C yolk–shell microspheres with a carbon content of 15 wt% exhibited superior cycling and rate performances compared with those of the bare SnO2–Co3O4 microspheres with the same morphologies. The discharge capacities of SnO2–Co3O4 and SnO2–CoO–C at the 100th cycle were 565 and 812 mA h g−1, while their capacity retentions calculated from the second cycle were 51 and 97%, respectively. Furthermore, SnO2–CoO–C yolk–shell microspheres exhibited high and stable reversible capacities even at an extremely high current density of 30 A g−1. The discharge capacity of SnO2–CoO–C yolk–shell microspheres at the 1000th cycle at a current density of 3.0 A g−1 was 775 mA h g−1. The synergetic effect of the pitch-derived carbon with a high electrical conductivity, catalytic effect of the metallic Co, crystal growth minimization of metallic Co and Sn by reciprocal action, and yolk–shell structure with empty shells provided the SnO2–CoO–C yolk–shell microspheres with excellent lithium-ion storage performances.

This paper reports the effect of the freeze-thaw on the suspension stability, particle size distribution, and thermal conductivity of EG/water-based nanofluids containing Al2O3 nanoparticles that can be used as improved working fluid for cooling systems. The EG/water-based Al2O3 nanofluids were prepared using a two-step method with a nanodisperser and decanting processes. To investigate the effect of freeze-thaw on the suspension stability and thermal conductivity of nanofluids, the prepared nanofluids were frozen at -32°C for 24 hours using a refrigerating chamber, and then they were completely thawed at room temperature for 24 hours. The suspension stability of the thawed nanofluids was quantitatively analysed for over a day using a Turbiscan. In addition, the particle size distributions and deformation of nanoparticles dispersed in the nanofluids were measured using a particle size analyzer (PSA) and TEM. Also, the thermal conductivity of the nanofluids was measured using a transient hot wire (THW) method in temperature from -10 to 70°C. Based on the results, we show that the suspension stability, thermal conductivity, and particle size of EG/water-based Al2O3 nanofluids were not affected by low temperature.

A method of microalgae-templated spray drying to develop hierarchical porous Fe3O4/C composite microspheres as anode materials for Li-ion batteries was developed. During the spray-drying process, individual microalgae serve as building blocks of raspberry-like hollow microspheres via self-assembly. In the present study, microalgae-derived carbon matrices, naturally doped heteroatoms, and hierarchical porous structural features synergistically contributed to the high electrochemical performance of the Fe3O4/C composite microspheres, enabling a discharge capacity of 1375 mA&middot, h&middot, g&minus, 1 after 700 cycles at a current density of 1 A/g. Notably, the microalgal frameworks of the Fe3O4/C composite microspheres were maintained over the course of charge/discharge cycling, thus demonstrating the structural stability of the composite microspheres against pulverization. In contrast, the sample fabricated without microalgal templating showed significant capacity drops (up to ~40% of initial capacity) during the early cycles. Clearly, templating of microalgae endows anode materials with superior cycling stability.

Silicon, as a promising next-generation anode material, has drawn special attention from industries due to its high theoretical capacity (around 3600 mAh g−1) in comparison with conventional electrodes, e.g., graphite. However, the fast capacity fading resulted by a large volume change hinders the pragmatic use of Si anodes for lithium ion batteries. In this work, we propose an efficient strategy to improve the cyclability of upcycled Si nanomaterials through a simple battery operation protocol. When the utilization degree of Si electrodes was decreased, the electrode deformation was significantly alleviated. This directly led to an excellent electrochemical performance over 100 cycles. In addition, the average charge (delithation) voltage was shifted to a lower voltage, when the utilization degree of electrodes was controlled. These results demonstrated that our strategic approach would be an effective way to enhance the electrochemical performance of Si anodes and improve the cost-effectiveness of scaling-up the decent nanostructured Si material.

Silicon is considered an important industrial element, primarily owing to its use in semiconductors, which are key components of various electronic devices; thus, the development of low-cost and efficient purification silicon processes has become a research focus. In this study, we developed a new process using ammonium fluoride (NH4F) to remove residual silica (SiO2) and generate nanopores on raw silicon (Si) materials without the use of highly toxic reagents and expensive procedures. We conducted low-temperature heat treatment of raw Si with NH4F under an inert atmosphere and found that the purity of raw Si was improved to a level similar to that of raw Si treated with hydrofluoric acid solution. Moreover, through this process, the surface area of raw Si was increased by surface tearing and the formation of nanopores. We also proposed a reaction mechanism for removing residual SiO2 from raw Si through X-ray diffraction analysis and demonstrated the safety of the process by analyzing the by-products generated during the heat treatment. When the modified Si material was applied to Li-ion battery anodes, they showed improved capacity, initial coulombic efficiency, and cycle performance as compared with those using raw Si material. We expect that this new NH4F-based method will not only be used to modify various Si materials for their efficient application, but will also be used to obtain nanostructured materials that require the removal of SiO2 during synthesis.

Despite the high theoretical capacity, silicon (Si) anodes in lithium-ion batteries have difficulty in meeting the commercial standards in various aspects. In particular, the huge volume change of Si makes it very challenging to simultaneously achieve high initial Coulombic efficiency (ICE) and long-term cycle life. Herein, we report spray pyrolysis to prepare Si-SiOx composite using an aqueous precursor solution containing Si nanoparticles, citric acid, and sodium hydroxide (NaOH). In the precursor solution, Si nanoparticles are etched by NaOH with the production of [SiO4]4-. During the dynamic course of spray pyrolysis, [SiO4]4- transforms to SiOx matrix and citric acid decomposes to carbon surface layer with the assistance of NaOH that serves as a decomposition catalyst. As a result, a Si-SiOx composite, in which Si nanodomains are homogeneously embedded in the SiOx matrix with carbon surface layer, is generated by a one-pot process with a residence time of only 3.5 s in a flow reactor. The optimal composite structure in terms of Si domain size and Si-to-O ratio exhibited excellent electrochemical performance, such as reversible capacity of 1561.9 mAh g-1 at 0.06C rate and ICE of 80.2% and 87.9% capacity retention after 100 cycles at 1C rate. J.W.C. acknowledges the financial support by the National Research Foundation of Korea (NRF) grant funded by the Korea government (MEST) (NRF-2015R1A2A1A05001737). This work was also made possible by NPRP Grant No. NPRP 7-301-2-126 from the Qatar National Research Fund (a member of Qatar Foundation). Scopus

Li-rich cathode materials have intrinsically poor rate capability along with low electronic conductivity, which remain as unsolved drawbacks limiting their use in applications that require cathode material with layered structures. Here, we prepared surface-modified Li-rich cathode materials to address these drawbacks via reductive treatment. After reductive treatment, we confirmed that these samples feature better electrochemical performance; the reductive treated samples show higher capacity and better capacity retention during cycling compared to samples treated only in air. In particular, the reductive treated samples showed excellent rate capability of 168 mAh g−1 at a current density of 400 mA g−1 compared to 138 mAh g−1 for the air treated sample. We confirmed that reductive treatment reduces the resistance for charge transfer based on electrochemical impedance spectroscopy analysis. We also investigated the effects of reductive treatment on the cathode structure of both samples using x-ray diffraction as well as x-ray photoelectron spectroscopy.

Status epilepticus is a severe neurological disease associated with substantial mortality and health-care cost. Treatment of status epilepticus should proceed without delay even in the pre-hospital setting because prolonged generalized convulsive seizures may lead to neuronal injury, pharmacoresistance, and poor prognosis. These concepts have led to the establishment of an updated treatment algorithm emphasizing a more rapid escalation to third-line therapy for refractory convulsive status epilepticus. This article reviews the guidelines and current evidence for the management of status epilepticus.

Background Hashimoto's encephalopathy (HE) and anti N-methyl-D-aspartate receptor (NMDAR) encephalitis have clinical overlaps. Case report A 70-year-old woman presented with acutely developed confusion, disorientations and psychosis. HE was suspected based on goiter, markedly elevated anti-thyroglobulin and anti-thyroid peroxidase antibody. She was placed on high dose steroid and intravenous immunoglobulins administration, which did not ameliorate her symptoms. After the antibodies to the NMDAR were identified, weekly 500 mg of rituximab with 4 cycles were started. The current followed up indicated a complete recovery. Conclusions The possible associations between NMDAR antibody and autoimmune thyroid antibodies in anti-NMDAR encephalitis with positive thyroid autoantibodies remain unclear. However, a trend toward a higher incidence of NMDAR antibody in patients with autoimmune thyroid antibodies than without has been observed. Cases of encephalitis with only NMDAR antibody (pure anti-NMDAR encephalitis) also occur. Therefore, it is important for clinicians to know the clinical and pathogenic differences between anti-NMDAR encephalitis with positive thyroid autoantibody and pure anti-NMDAR encephalitis for relevant treatment, predicting prognosis, and future follow-up.

Dodecylamine (DDA) was functionalized on Fe2O3 nanocrystals (NCs) by a solvothermal process to allow electrostatic interaction on Bronsted acid sites induced on the surface of NCs, followed by carbonization to convert DDA into a thin layer of carbon on single Fe3O4 NCs. The obtained carbon composite (IOC-Fe3O4) is composed of Fe3O4 NCs a few nanometers in size, each uniformly coated with a thin carbon layer. The carbon coating reduces the resistance at the NC-to-NC interface within the composite and retains a short lithium diffusion length by inhibiting crystal growth, as well as accommodating the volume change of Fe3O4 during charge–discharge. The composite electrode exhibited a high reversible capacity of 1027 mA h g−1 in a lithium ion battery, as well as 100% capacity retention after 300 cycles and rate performance of 563 mA h g−1 at 3 A g−1, which was achieved with only 4.2 wt% carbon in the composite. The relationship between the enhanced diffusion kinetics of IOC-Fe3O4 and excellent electrochemical performances is demonstrated through a voltammetric charge technique.

Copper-based materials as electrode materials have been attracted attention for their various merits such as nature abundance, low-cost, easy preparation, chemical stability, high theoretical specific capacity, and environmental friendliness. Metal selenite materials transforming into heterostructured metal oxide and selenide during the first cycle was considered as efficient anode materials for lithium-ion batteries. Herein, copper selenite microspheres were synthesized by applying facile spray pyrolysis process and for the first time, their conversion reaction mechanism with lithium-ions was systematically comprehended by various in-situ and ex-situ analysis. The selenization of spray pyrolysis product (Cu nitrate-polyvinylpyrrolidone composite) yielded cooper selenide (CuxSe)-C composite. Subsequently, partial oxidation process produced carbon-free hollow cooper selenite (Cu2O(SeO3)) microspheres. Through the various technical measurements, the following reversible reaction mechanism of Cu2O(SeO3) phase could be confirmed from the second cycle onward: CuO + CuSe + 4Li+ + 4e− ↔ 2Cu + Li2O + Li2Se. Moreover, hollow Cu2O(SeO3) microspheres showed excellent cycling and rate performances. The discharge capacity of Cu2O(SeO3) for 500th cycle at a current density of 3.0 A g−1 is 645 mA h g−1 and exhibited a stable reversible capacity even at extremely high current density of 30 A g−1.

Although silicon has attracted attention as a promising anode material for lithium ion batteries due to its high theoretical capacity and relatively low discharge potential, the issue of large volume expansion and contraction during its de-/alloying reaction with Li has resulted in the development of nanostructured electrode design and coating methods using suitable carbon sources to improve the stability of the electrode. Pitch is regarded as an attractive carbon coating source owing to its mesophase characteristics, high mechanical strength, and electrical conductivity. In this study, three-dimensional porous pitch-derived carbon coated Si nanoparticles-carbon nanotube (Si-CNT@PC) composite microspheres were successfully synthesized by spray pyrolysis and a following pitch infiltration process. Uniformly distributed Si nanoparticles, acid-treated multiwall CNTs, and polystyrene (PS) nanobeads enabled the formation of porous structured Si-CNT composite microspheres by spray pyrolysis. Uniform infiltration of pitch dissolved in tetrahydrofuran followed by a carbonization process resulted in Si-CNT@PC microspheres. The uniquely structured Si-CNT@PC microspheres exhibited superior electrochemical properties compared with Si-CNT microspheres not coated with carbon. The synergetic effects of carbon-coated Si nanoparticles, macroporous structure formed by decomposition of PS nanobeads, and the CNT backbone resulted in excellent lithium-ion storage performance of Si-CNT@PC microspheres. The discharge capacities of Si-CNT and Si-CNT@PC at a current density of 1 A g−1 for the 200th cycle were 51 and 1209 mA h g−1, respectively.

A 63-year-old man presented with a 1.5-year history of progressive personality changes. Clinical evaluations revealed severe frontal dysfunction and bilateral frontal atrophy/glucose hypometabolism. He was diagnosed as probable behavioral variant frontotemporal dementia. He continued to decline, and died at the age of 66. At autopsy, numerous tau-positive gilial threads and coiled bodies were observed in the white matter. Tau-positive astrocytic plaques and neuronal cytoplasmic inclusions were also seen in cerebral cortices, which were compatible with corticobasal degeneration. J Korean Neurol Assoc 33(3):178-182, 2015

Eun-Joo Kim, MD, Eun-Hye Oh, MD, Ki-Tae Kim, MD, Yoori Jung, MD, Jeong Hee Lee, MD, Jae-Hyeok Lee, MD, Young Min Lee, MD, Seong-Jang Kim, MD, Jin-Hong-Shin, MD, Myung-Jun Shin, MD, Myung Jun Lee, MD, Jae Woo Ahn, MD, Suk Sung, MD, Kyung-Un Choi, MD, Dae Soo Jung, MD, William W. Seeley, MD, Gi Yeong Huh, MD Departments of Neurology, Pathology, Psychiatry, Nuclear Medicine, Rehabilitation Medicine, Anatomy, and Forensic Medicine, Pusan National University School of Medicine, Yangsan, Korea Memory and Aging Center, University of California San Francisco, CA, USA

Anti N-methyl-D-aspartate (NMDA) receptor encephalitis is one of the most common types of autoimmune synaptic encephalitis. Anti-NMDA receptor encephalitis commonly occurs in young women with ovarian teratoma. It has variable clinical manifestations and treatment responses. Sometimes it is misdiagnosed as a psychiatric disorder or viral encephalitis. To the best of our knowledge, anti-NMDA receptor encephalitis is a rare condition in pregnant women. We report a case of anti-NMDA receptor encephalitis in a pregnant woman who presented with abnormal behavior, epileptic seizure, and hypoventilation.

Background and purpose Long-term videoelectroencephalogram (video-EEG) monitoring is performed to diagnose an epileptic seizure and to investigate the differential diagnosis of paroxysmal events. To provoke an epileptic seizure, an exercise method is performed in some cases during long-term video-EEG recording in the epilepsy monitoring unit (EMU). The purpose of this study was two-fold: to assess the frequency and severity of adverse events associated with the use of an exercise bicycle and to find a way to safely use it in the EMU. Methods A retrospective survey was performed on all epileptic seizure videos recorded in the EMU from January 2012 to December 2013. Three hundred and fifty patients were included in this study. Results Eleven patients experienced an epileptic seizure while riding the exercise bicycle in the EMU. One patient's foot got stuck between the cycling pedal and its strap, and one patient fell off the exercise bicycle during the epileptic seizure. However, there were no serious adverse events over two years. Conclusion Epileptic seizures were not frequent while riding the exercise bicycle, and serious injuries did not occur. But, there is a need to improve the safety in the EMU to control the potentially dangerous factors associated with the use of the exercise bicycle and to continuously monitor the patients with help from the staff.

Spherical Li 1.167 − x Na x Ni 0.18 Mn 0.548 Co 0.105 O 2 (0 ⩽ x ⩽ 0.1) particles were prepared by spray pyrolysis, and subjected to electrochemical characterization for lithium battery applications. It was confirmed that Na doping enhances the charge/discharge rate capability. The structure of prepared samples was characterized by XRD: the c -axis lattice parameter increases with increase in the amount of Na ions (parameterized by x , above). The Na-doped sample with x = 0.05 shows capacities of 208 and 184 mA h g −1 at high current densities of 1.0 C and 2.0 C, respectively. These values are enhanced, compared to values of 189 and 167 mA h g −1 for the bare sample. The ratio of the capacity at 1.0 C to that at 0.1 C is enhanced from 77% for the bare sample to 84% for the Na-doped sample with x = 0.05. The Li diffusion coefficients obtained from the galvanostatic intermittent titration technique (GITT) are higher for Na-doped samples than for the bare sample. In particular, the Na-doped sample ( x = 0.05), in the potential range around 4 V, has a higher D Li+ value of 3.34 × 10 −9 cm 2 s −1 , compared with 1.35 × 10 −9 cm 2 s −1 for the bare sample. The Na-doped samples (0 x x = 0.05) shows a capacity retention of 92% compared to 83% for the bare sample.

Background Central core disease (CCD) is a congenital myopathy characterized by distinctive cores in muscle fibers. Mutations in the gene encoding ryanodine receptor 1 (RYR1) have been identified in most CCD patients. Case report Two unrelated patients presented with slowly progressive or nonprogressive proximal muscle weakness since childhood. Their family history revealed some members with the same clinical problem. Histological analysis of muscle biopsy samples revealed numerous peripheral cores in the muscle fibers. RYR1 sequence analysis disclosed a novel mutation in exon 101 (c.14590T>C) and confirmed a previously reported mutation in exon 102 (c.14678G>A). Conclusions We report herein two families with CCD in whom missense mutations at the C-terminal of RYR1 were identified. Although it has been accepted that such mutations are usually associated with a severe clinical phenotype and clearly demarcated central cores, our patients exhibited a mild clinical phenotype without facial muscle involvement and skeletal deformities, and atypical cores in their muscle biopsy specimens.

The rice husk is the outer covering of a rice kernel and protects the inner ingredients from external attack by insects and bacteria. To perform this function while ventilating air and moisture, rice plants have developed unique nanoporous silica layers in their husks through years of natural evolution. Despite the massive amount of annual production near 10 8 tons worldwide, so far rice husks have been recycled only for low-value agricultural items. In an effort to recycle rice husks for high-value applications, we convert the silica to silicon and use it for high-capacity lithium battery anodes. Taking advantage of the interconnected nanoporous structure naturally existing in rice husks, the converted silicon exhibits excellent electrochemical performance as a lithium battery anode, suggesting that rice husks can be a massive resource for use in high-capacity lithium battery negative electrodes.

Nano-sized Ag–Pd (50–50) alloy powders coated with Pb-based glass material with low and high glass transition temperature are directly prepared by high-temperature flame spray pyrolysis. Nano-sized Ag–Pd–glass composite powder is formed from the evaporated vapors by nucleation and growth process, and then glass material moves out to the outside of the powder by crystallization process of alloy. The thickness of the glass coating layer measured from the TEM image is 2.8 nm. The mass changes of the Ag–Pd alloy and Ag–Pd–glass composite powders in the TG analysis under 900 °C are 10.9 and 6.8%, respectively. Glass materials improve the uniformity and density of the Ag–Pd electrode layers by act as sintering agent and adhesion improvement. The Ag–Pd electrode formed from the composite powders with high glass transition temperature glass material has thin and uniform thickness. The specific resistances of the electrodes formed from the nano-sized Ag–Pd–glass composite powders are 0.27, 0.09, and 0.03 mΩ cm at firing temperatures of 700, 800, and 900 °C, respectively.

ZnO–B2O3–SiO2–CaO glass frits were directly prepared by high temperature spray pyrolysis for use in Cu electrodes. The frits prepared at temperatures above 1400 °C were spherical, amorphous, of fine size and dense structure. The mean particle size and geometric standard deviation of the frits prepared at 1400 °C were 0.87 μm and 1.37, respectively. The temperatures of glass transition, crystallization and melting were 454, 534 and 800 °C, respectively. The glass layer fired at 800 °C had a dense structure due to the material's complete melting, despite some crystals being observed by SEM. A copper electrode formed from copper paste with glass frits had a dense structure when fired at 800 °C. The specific resistances of electrodes formed from copper paste with and without glass frits were 2.5 and 8.5 μΩ cm, respectively.

Bi-based glass powders with particle size of 34 nm were prepared by high-temperature flame spray pyrolysis. The glass transition temperature (Tg) of the powders was 442 °C. Dielectric layers fired at temperatures of 480 and 500 °C contained voids, while those fired at temperatures above 540 °C had clean surfaces and no voids. The dielectric layers sintered at temperatures of 560 and 580 °C had transmittances of 70% in the visible range. Further, it was observed that the dielectric layers formed from the nanosized glass powders obtained from spray solutions containing excess boron had higher transmittances (80% in the visible range at a sintering temperature of 580 °C) than the layers formed from spray solutions containing stoichiometric amounts of boron.

The La0.8Sr0.2Ga0.8Mg0.2O2.8 (LSGM) precursor powders with large size, hollow and thin wall structure are prepared by spray pyrolysis from the spray solution with ethylenediaminetetraacetic acid (EDTA). The precursor powders turned into the nano-sized powders after post-treatment and grinding processes. The pellets formed from the powders obtained from the spray solution with EDTA had pure LSGM phase, clean surface and dense structure with small pores after sintering at 1300°C. On the other hand, the LSGM pellet formed from the powders obtained from the spray solution without EDTA had small impurity phase, porous structure and rough surface. The conductivity of the LSGM electrolyte was 0.006 S/cm at a measurement temperature of 600°C.

Fine size glass powders with a 21.5 mol% PbO–50.5 mol% B2O3–16 mol% SiO2–12 mol% BaO–0.5 mol% CuO composition were directly prepared by spray pyrolysis. The glass powders prepared at 1000 °C had spherical shape and dense inner structure. The glass transition temperature (Tg) of the glass powders with the mean size of 0.84 μm was 493 °C. The number of voids in fired dielectric layers decreased with increasing the preparation temperature of the glass powders, and the dielectric layer formed from the glass powders prepared by spray pyrolysis at a temperature of 1000 °C had no voids inside the layer. The transmittances of the dielectric layer formed from the glass powders prepared at a temperature of 1000 °C were higher than 70% within the visible range. The mean sizes of the powders were changed from 0.36 to 1.0 μm when the concentrations of the spray solutions were changed from 0.03 to 1 M. The dielectric layers formed from the glass powders with small sizes had higher transmittances than those formed from the glass powders with large sizes.

Conductive silver–glass composite powders, which are promising candidates for novel electrode materials, were prepared by spray pyrolysis. Composite conducting powders had a core–shell structure, which was the same as that of glass-coated silver powders. The composite powders with a mean size of 0.63 μm had spherical shape and non-aggregation characteristic. Even at a low firing temperature of 450 °C, the conductive layer formed from the composite powders had a dense structure and low pore volume. The specific resistances of the conductive layers formed from the silver pastes with and without glass powders were 9 μΩ cm and 19 μΩ cm, respectively. However, the specific resistance of the conducting layer formed from the composite powders was as low as 3.6 μΩ cm.

Bi-based glass powders as additive for silver conducting pastes were prepared by spray pyrolysis. The glass powders formed from the spray solution with low concentration of 0.025 M had bimodal size distribution with nanometer and submicron sizes. However, glass powders with spherical shape and narrow size distribution were prepared from the spray solutions with concentrations of 0.05 and 0.5 M. The mean size of the glass powders increased from 0.34 to 0.7 μm when the concentrations of the spray solutions changed from 0.05 to 0.5 M. The glass transition temperature of the glass powders with the mean size of 0.34 and 0.70 μm were 382 and 396 °C, respectively. The glass layers fired at 450 °C had clean surfaces irrespective of the mean size of the glass powders. Silver conducting films were formed by melting of the silver powders irrespective of the mean sizes of the glass powders at firing temperatures between 400 and 500 °C. The specific resistances of the silver conducting films change from 3.13 to 4.03 μΩ cm according to the mean size of the glass powders at a firing temperature of 500 °C.

Samaria-doped ceria (SDC) nanoparticles were prepared by spray pyrolysis. The means sizes of the samaria-doped ceria nanoparticles were controlled from 21 to 150 nm by changing the calcination temperatures between 700 and 1200 °C. The pellets formed from the SDC particles calcined at temperatures between 700 and 1000 °C had similar grain sizes between 0.75 and 0.82 μm. However, pellet formed from the SDC particles calcined at a temperature of 1200 °C had large grain size of 1.22 μm. The pellet formed from the SDC particles calcined at a temperature of 1000 °C had slightly smaller resistance of grain-boundary than those of the pellets formed from the SDC particles calcined at temperatures between 700 and 900 °C. However, the pellet formed from the SDC particles calcined at a temperature of 1200 °C had low resistance of grain-boundary. The pellet formed from the SDC particles calcined at a temperature of 1200 °C had conductivity of 44.65 × 10 −3 S cm −1 at a measuring temperature of 700 °C that more twice than those of the pellets formed from the SDC calcined below 1000 °C.