• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.30 no.3
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• pp.74-83
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• 1998

The phenomenon of decrease in sizing efficiency when the stock temperature is increased is well recognized as summer sizing, and this is believed to be caused by uneven distribution of sizing agents on paper surface most often incurred by coagulation of sizing agents. When unevenly sized paper is used as coating base stock, nonuniform consolidation of the coating layer may result, which, in turn, causes uneven distribution of binder on coating surface. This causes nonuniform ink absorption to produce print mottle. In this study the effects of simple or polymeric electrolytes, storage temperature and time on the coagulation of cationic dispersed rosin size were investigated using a turbidity measurement method which was verified to correlate well with the particle size of rosin emulsion or its coagulates. Handsheets sized with rosin dispersions coagulated under various conditions were prepared and their sizing degree and coated paper properties including gloss and ink density were examined. The relationship between the sizing nonuniformity of coated papers and its ink absorption property was evaluated. Turbidity of rosin emulsion increased as the storage temperature and time were increased. Addition of simple or polymeric electrolytes caused reduction in $zeta$ -potential of the rosin dispersion and accelerated the coagulation tendency substantially. Reversion of the $zeta$ -potential of rosin dispersion, however, did not occur when coagulation was induced with simple electrolytes. On the other hand, addition of an anionic polyelectrolyte reversed the $zeta$ -potential of the flocculated rosin dispersion. This indicated that electrical double layer compaction and bridging flocculation were coagulation mechanisms for simple and polymeric electrolytes, respectively. Sizing degree decreased as coagulation of rosin was increased. Paper gloss, ink gloss and ink density were increased when sizing degree of base stock was increased most probably due to prevention of base paper swelling and increased binder migration to coating surface. This suggested that uneven printing ink density occurred when uneven sizing development was induced by coagulation of rosin particles.

• Journal of the Semiconductor & Display Technology
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• v.22 no.1
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• pp.28-32
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• 2023

Recently, the use of stable lithium nanostructures as substrates and electrodes for secondary batteries can be a fundamental alternative to the development of next-generation system semiconductor devices. However, lithium structures pose safety concerns by severely limiting battery life due to the growth of Li dendrites during rapid charge/discharge cycles. Also, enabling long cyclability of high-voltage oxide cathodes is a persistent challenge for all-solid-state batteries, largely because of their poor interfacial stabilities against oxide solid electrolytes. For the development of next-generation system semiconductor devices, solid electrolyte nanostructures, which are used in high-density micro-energy storage devices and avoid the instability of liquid electrolytes, can be promising alternatives for next-generation batteries. Nevertheless, poor lithium ion conductivity and structural defects at room temperature have been pointed out as limitations. In this study, a low-dimensional Graphene Oxide (GO) structure was applied to demonstrate stable operation characteristics based on Li+ ion conductivity and excellent electrochemical performance. The low-dimensional structure of GO-based solid electrolytes can provide an important strategy for stable scalable solid-state power system semiconductor applications at room temperature. The device using uncoated bare NCA delivers a low capacity of 89 mA h g-1, while the cell using GO-coated NCA delivers a high capacity of 158 mA h g−1 and a low polarization. A full Li GO-based device was fabricated to demonstrate the practicality of the modified Li structure using the Li-GO heterointerface. This study promises that the lowdimensional structure of Li-GO can be an effective approach for the stabilization of solid-state power system semiconductor architectures.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.37 no.4
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• pp.445-450
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• 2024

The expansion of lithium-ion battery usage beyond portable electronic devices to electric vehicles and energy storage systems is driven by their high energy density and favorable cycle characteristics. Enhancing the stability and performance of these batteries involves exploring solid electrolytes as alternatives to liquid ones. While sulfide-based solid electrolytes have received significant attention for commercialization, research on amorphous-phase glass solid electrolytes in oxide-based systems remains limited. Here, we investigate the glass transition temperatures and sintering behaviors by changing the molecular ratio of Li₂O/B₂O₃ in borate glass comprising Li₂O-B₂O₃-Al₂O₃ system. The glass transition temperature is decreasing as increasing the amount of Li₂O. When we sintered at 450℃, just above the glass transition temperature, the samples did not consolidate well, while the proper sintered samples could be obtained under the higher temperature. We successfully obtained the borate glass ceramics phases by melt-quenching method, and the sintering characteristics are investigated. Future studies could explore optimizing ion conductivity through refining processing conditions, adjusting the glass former-to-modifier ratio, and incorporating additional Li salt to enhance the ionic conductivity.

• Journal of the Korean Electrochemical Society
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• v.17 no.1
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• pp.26-29
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• 2014

The corrosion behavior of stainless steel 304 (SS 304), titanium, nickel and aluminium is studied by immersion and anodic polarization tests in non-aqueous electrolytes. Tetraethyl ammonium tetrafluoroborate is used as a supporting electrolyte in the three kinds of solvents. The immersion test shows that chemical corrosion rate in propylene carbonate-based electrolyte is lower than those in acetonitrile- or ${\gamma}$-butyrolactone-based electrolytes. Surface analyses do not reveal any corrosion product formed after the immersion test. In the anodic polarization tests, a higher concentration of supporting electrolyte gives a higher current density. In addition, a higher temperature increases the current density in the active region and reduces the potential range in the passive region. SS 304 shows the highest corrosion potential while Al shows the lowest corrosion potential and the highest current density in all studied conditions. Based on the conducted corrosion tests, the corrosion resistance of metal substrates in the organic solvents can be sorted in descending order as follows: SS 304 - Ti - Ni - Al.

• Journal of the Korean Electrochemical Society
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• v.14 no.2
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• pp.92-97
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• 2011

In this study we have investigated the Li-ion coordination, thermal behavior and electrochemical stability of N-butyl-N-methyl-pyrrolidinium bis(trifluoromethanesulfonyl)imide ($Py_{14}TFSI$) with lithium bis(trifluoromethanesulfony)imide (LiTFSI) doping intended for use as electrolytes for lithium batteries. The ionic conductivity is reduced and glass transition temperature ($T_g$) increases with LiTFSI doping concentration. Also, the electrochemical stability increases with LiTFSI doping. A high LiTFSI doping could enhance the electrochemical stability of electrolytes for lithium batteries, whereas the decrease in the ionic conductivity limits the capacity of the battery.

• Journal of Veterinary Clinics
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• v.28 no.4
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• pp.352-356
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• 2011

Abstract: This study was aimed to diagnose acid-base disorders of dogs with canine parvoviral enteritis (CPE) and data to establish a rational fluid therapy regimen for patients with CPE. A total of 43 dogs which had clinical signs of CPE and had detected canine parvovirus by polymerase chain reaction, were bled anaerobically from jugular vein at the time of admission. Blood chemical test, determination of electrolytes and blood gas analysis were conducted, and calculated values were obtained from each measured items. The values of blood chemical and electrolytes of dogs with CPE were various depending on the degree of clinical signs, and these tests were not specific to diagnose for CPE. Hypochloremia (20.9%), hyperchloremia (11.6%), hypokalemia (7.0%), hyperkalemia (11.6%), hyponatremia (9.3%) and hypernatremia (18.6%) were diagnosed as abnormalities of electrolytes from 43 dogs with CPE. The 29 out of 43 dogs (67.4%) were metabolic acidosis and 3 dogs (7.0%) were metabolic alkalosis. The acid-base status of 11 dogs out of 43 dogs (25.6%) was normal.

• Transactions on Electrical and Electronic Materials
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• v.15 no.4
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• pp.189-192
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• 2014

Yttria-stablized zirconia (YSZ) is the most commonly used electrolyte material, but the reduction in working temperature leads to insufficient ionic conductivity. Ceria based electrolytes (GDC) are more attractive in terms of conductivity at low temperature, but these materials are well known to be reducible at very low oxygen partial pressure. The reduction of electrolyte resistivity is necessary to overcome cell performance losses. So, thin YSZ/GDC bilayer technology seems suitable for decreasing the electrolyte resistance at lower operating temperatures. Bilayer electrolytes composed of a galdolinium-doped $CeO_2$ ($Ce_{0.9}Gd_{0.1}O_{1.95}$, GDC) layer and yttria-stabilized $ZrO_2$ (YSZ) layer with various thicknesses were deposited by RF sputtering and E-beam evaporation. The bilayer electrolytes were deposited between porous Ni-GDC anode and LSM cathode for anode-supported single cells. Thin film structure and surface morphology were investigated by X-ray diffraction (XRD), using $CuK{\alpha}$-radiation in the range of 2ce morphol$^{\circ}C$. The XRD patterns exhibit a well-formed cubic fluorite structure, and sharp lines of XRD peaks can be observed, which indicate a single solid solution. The morphology and size of the prepared particles were investigated by field-emission scanning electron microscopy (FE-SEM). The performance of the cells was evaluated over $500{\sim}800^{\circ}C$, using humidified hydrogen as fuel, and air as oxidant.

• Biomedical Science Letters
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• v.17 no.3
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• pp.203-209
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• 2011

Magnesium (Mg) plays an essential role in physiological and metabolic reactions. Recently, there has been an increased interest in the role of Mg deficiency, particularly the relationship between serum Mg value and inflammatory response. This study was designed to determine the relationship between serum Mg deficiency with inflammatory response, electrolytes and hematological alteration over long-term periods. Sixteen male Sprague-Dawley rats were divided into two groups: control (n=8), and Mg deficiency group (MgD group, n=8). Chow and normal water (tap water) were regularly provided to the control group and Mg-depleted chow and third distilled water were regularly provided for 60 days to the MgD group. Body weights, Serum Mg, $K^+$, inorganic phosphorus (IP) and total iron binding capacity (TIBC) levels in the MgD group were lower than those of the control group (P<0.05). Granulocyte fraction and MCV, RDW and PDW levels were higher, whereas lymphocyte fraction, erythrocyte, hemoglobin and MCHC levels were lower in the MgD group than in the control group (P<0.05). MCP-1 and TNF-${\alpha}$ levels in the MgD group were greater than those of the control group (P<0.05). In conclusion, the results of the present study suggest that Mg deficiency over a long-term period had not altered total leukocyte concentration in the blood, but had detrimental effects, including disturbances of electrolytes balance, disturbance of iron indices, potential anemia and elevation of pro-inflammatory cytokine. However, further studies should be performed to determine the relationship between serum Mg deficiency and major organ damage or alteration.

• YAKHAK HOEJI
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• v.34 no.2
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• pp.88-101
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• 1990

Captopril, angiotensin converting enzyme (ACE) inhibitor, when given intravenously in dog, elicited the diuretic action along with the increases of glomerular filtration rates (GFR), renal plasma flow (RPF) and osmolar clearances (Cosm) with no changes of free water clearnces ($C_{H_2O}$), and then captopril produced the enlargement of excretion rates of electrolytes in urine and the reduction of reabsorption rates of electrolytes in renal tubles. Captopril, when given into a renal artery, exhibited no changes of renal function in the experinental kidney, whereas diuretic action with the same mechanism as shown in intravenous captopril in control kidney. Captopril, when injected into a carotid artery, showed increases in rates of urine flow in a small does which did not affect on renal action when it was administered intravenusly. Diuretic action induced by captopril was not influenced by renal artery denervation, propranolol and angiotensin II inhibiters. Above results suggest that captopril produced diuretic action along with renal hemodynamic changes by slight contraction of vas efferense and reduction of reabsorption rate of electrolytes in renal tubules, especilly distal tubules, that may be mediatedby endogenous substances.

• 한국전기화학회:학술대회논문집
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• 1998.12a
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• pp.153-166
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• 1998

Lithium ion Batteries commercially available since the early nineties in Japan are going to be more and more important for portable electronic devices and even EV applications. Today several companies around the world are working hard to join to market for Lithium secondary batteries. Based on the growing interest for commercial use of batteries also the materials have to be reviewed in order to meet large scale production needs. The requirements especially for electrolytes for lithium batteries are extremely high. The solvents and the lithium salts should be of highest purity. So the supply of these chemicals including packaging, transportation and storage but also the handling in production are critical items in this field. Frolic impurities are very critical for LiPF6 based electrolytes. The influence of water is tremendous. But also the other protic impurities like alcoholes are playing an Important role for the electrolyte quality. The reaction of these species with LiPF6 leads to formation of HF which further reacts with cathode materials (spinel) and anode. To understand the role of the protic impurities more clearly the electrolyte was doped with such compounds and was analyzed for protic impurities and HF. These results which directly show the relation between impurities and quality will be presented and discussed. In addition several investigations on different packaging materials as well as methods to analyze and handle the sensititive material will be addressed. These questions which are only partly discussed in literature so far and never been investigated systematically cover some of the key parameters for understanding of the battery chemicals. This investigation and understanding however is of major importance for scientist and engineers in the field of Lithium ion and Lithium polymer batteries.