• 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.

• Membrane Journal
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• v.34 no.2
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• pp.114-123
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• 2024

Hydrogen isotopes can be categorized into light hydrogen, heavy hydrogen, and tritium based on the number of neutrons, each of which is used in specific fields. Specifically, deuterium is of interest in the electronics industry, nuclear energy industry, analytical technology industry, pharmaceutical industry, and telecommunications industry. Conventional methods such as cold distillation, thermal cycling absorption processes, Girdler sulfide processes, and water electrolysis have their own advantages and disadvantages, leading to the need for alternative technologies with high separation and energy efficiency. In this context, membrane-based hydrogen isotope separation is one of the promising solutions to reduce energy consumption. In this review, we will present the state-of-the-art in hydrogen isotope separation using membranes and their operating principles. The technology for separating hydrogen isotopes using membranes is just beginning to be conceptualized, and many challenges remain to be overcome. However, if achieved, the economic benefits are expected to be significant. We will discuss future research directions for this purpose.

• The Plant Pathology Journal
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• v.25 no.3
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• pp.280-285
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• 2009

Powdery and downy mildews caused by Sphaerotheca fusca and Pseudoperonospora cubensis are the most common and serious diseases of cucumber worldwide. In spite of the introduction of highly effective systemic fungicides, control of these diseases remains elusive. Hence, this study aimed to develop an alternative method to chemicals in controlling the diseases by using different types of cooking oil. Egg yolk, which contains a natural emulsifier, lecithin, was selected as a surfactant to emulsify the oils. Among the different cooking oils used, soybean, canola (rape seed), safflower, sunflower, olive, and corn oils showed over 95% control values against powdery mildew of cucumber in a greenhouse test. In particular, 0.3% canola oil emulsified with 0.08% yolk (1 yolk and 60 ml canola in 20 l spray) was found to be the most effective. The treatment resulted in 98.9% and 96.3% control efficacies on powdery and downy mildews, respectively, of cucumber in the field. Canola oil exhibited direct and systemic effect, wherein powdery mildew of cucumber was suppressed only on treated leaves but not on non-treated leaves in a plant, while mycelia and conidia of the pathogen were severely distorted or destroyed by the treatment. The prospect of using the canola oil and yolk mixture as a natural fungicide is highly promising because of its effectiveness, availability, low cost, simple preparation, and safety to humans and the environment. The use of the canola oil and yolk mixture is expected to be an effective fungicide for use in organic farming and home gardening.

• The Plant Pathology Journal
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• v.36 no.4
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• pp.335-345
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• 2020

Tomato grey mould has been one of the destructive fungal diseases during tomato production. Ten mM of menadione sodium bisulfite (MSB) was applied to tomato plants for eco-friendly control of the grey mould. MSB-reduced tomato grey mould in the 3rd true leaves was prolonged at least 7 days prior to the fungal inoculation of two inoculum densities (2 × 10⁴ and 2 × 10⁵ conidia/ml) of Botrytis cinerea. Protection efficacy was significantly higher in the leaves inoculated with the lower disease pressure of conidial suspension compared to the higher one. MSB-pretreatment was not effective to arrest oxalic acid-triggered necrosis on tomato leaves. Plant cell death and hydrogen peroxide accumulation were restricted in necrotic lesions of the B. cinereainoculated leaves by the MSB-pretreatment. Decreased conidia number and germ-tube elongation of B. cinerea were found at 10 h, and mycelial growth was also impeded at 24 h on the MSB-pretreated leaves. MSB-mediated disease suppressions were found in cotyledons and different positions (1st to 5th) of true leaves inoculated with the lower conidial suspension, but only 1st to 3rd true leaves showed decreases in lesion sizes by the higher inoculum density. Increasing MSB-pretreatment times more efficiently decreased the lesion size by the higher disease pressure. MSB led to inducible expressions of defence-related genes SlPR1a, SlPR1b, SlPIN2, SlACO1, SlChi3, and SlChi9 in tomato leaves prior to B. cinerea infection. These results suggest that MSB pretreatment can be a promising alternative to chemical fungicides for environment-friendly management of tomato grey mould.

• Membrane Journal
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• v.33 no.4
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• pp.181-190
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• 2023

Wastewater purification is one of the most important techniques for controlling environmental pollution and fulfilling the demand for freshwater supply. Various technologies, such as different types of distillations and reverse osmosis processes, need higher energy input. Capacitive deionization (CDI) is an alternative method in which power consumption is deficient and works on the supercapacitor principle. Research is going on to improve the electrode materials to improve the efficiency of the process. A reverse electrodialysis (RED) is the most commonly used desalination technology and osmotic power generator. Among many studies conducted to enhance the efficiency of RED, MXene, as an ion exchange membrane (IEM) and 2D nanofluidic channels in IEM, is rising as a promising way to improve the physical and electrochemical properties of RED. It is used alone and other polymeric materials are mixed with MXene to enhance the performance of the membrane further. The maximum desalination performances of MXene with preconditioning, Ti₃C₂T_x, Nafion, and hetero-structures were respectively measured, proving the potential of MXene for a promising material in the desalination industry. In terms of osmotic power generating via RED, adopting MXene as asymmetric nanofluidic ion channels in IEM significantly improved the maximum osmotic output power density, most of them surpassing the commercialization benchmark, 5 Wm^-2. By connecting the number of unit cells, the output voltage reaches the point where it can directly power the electronic devices without any intermediate aid. The studies around MXene have significantly increased in recent years, yet there is more to be revealed about the application of MXene in the membrane and osmotic power-generating industry. This review discusses the electrodialysis process based on MXene composite membrane.

• Korean Chemical Engineering Research
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• v.47 no.3
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• pp.362-367
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• 2009

Recently, the use of formic acid as a fuel for direct liquid fuel cells has emerged as a promising alternative to methanol. In the work presented herein, we evaluated direct formic acid fuel cells(DFAFCs) with various components under operating conditions, for example, the thickness of the proton exchange membrane, concentration of formic acid, gas diffusion layer, and commercial catalyst. The thickness of the proton exchange membrane influenced performance related to the fuel cross-over. To optimize the cell performance, we investigated on the proper concentration of formic acid and catalyst for the formic acid oxidation. Consequently, membrance-electrode assembly(MEA) consisted of $Nafion^{(R)}$-115 and the Pt-Ru black as a anode catalyst showed the maximum performance. This performance was superior to the DMFCs' one.

• Journal of Energy Engineering
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• v.20 no.1
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• pp.26-29
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• 2011

A promising alternative technology is the potential use of ice slurries as a secondary refrigerant in conventional cooling process. Ice slurries behave almost like a liquid and can be pumped through pipes although the energy capacity of ice slurries per unit volume is considerably higher than that for chilled water or brine due to the latent heat capacity of the ice particles. To give the basic data for the design of cooling systems using ice slurries, experimental study has been conducted to find out the performance of the cooling coil of show-case with ice slurries. Despite the fact that ice slurries entering the cooling coil had at least $5^{\circ}C$ higher temperature than that of R22, it was still capable of providing a similar cooling performance than that obtained with R22.

• IMMUNE NETWORK
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• v.4 no.3
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• pp.131-142
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• 2004

In recent years, adjuvants have received much attention because of the development of purified subunit and synthetic vaccines which are poor immunogens and require adjuvants to evoke the immune response. Therefore, immunologic adjuvants have been developed and testing for most of this century. During the last years much progress has been made on development, isolation and chemical synthesis of alternative adjuvants such as derivatives of muramyl dipeptide, monophosphoryl lipid A, liposomes, QS-21, MF-59 and immunostimulating complexes (ISCOMS). Biodegradable polymer microspheres are being evaluated for targeting antigens on mucosal surfaces and for controlled release of vaccines with an aim to reduce the number of doses required for primary immunization. The most common adjuvants for human use today are aluminum hydroxide and aluminum phosphate. Calcium phosphate and oil emulsions have been also used in human vaccination. The biggest issue with the use of adjuvants for human vaccines is the toxicity and adverse side effects of most of the adjuvant formulations. Other problems with the development of adjuvants include restricted adjuvanticity of certain formulations to a few antigens, use of aluminum adjuvants as reference adjuvant preparations under suboptimal conditions, non-availability of reliable animal models, use of non-standard assays and biological differences between animal models and humans leading to the failure of promising formulations to show adjuvanticity in clinical trials. The availability of hundreds of different adjuvants has prompted a need for identifying rational standards for selection of adjuvant formulations based on safety and sound immunological principles for human vaccines. The aim of the present review is to put the recent findings into a broader perspective to facilitate the application of these adjuvants in general and experimental vaccinology.

• Journal of the Korean Electrochemical Society
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• v.21 no.3
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• pp.55-60
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• 2018

The demand for LIBs with higher energy densities has increased continuously because the emergence of wider and more challenging applications including HEV and EV has became imperative. However, in the case of anode material, graphite is insufficient to meet this need. To meet such demand, several type of negative electrode materials like silicon, tin, SiO, and transition metal oxide have been investigated for the advanced lithium secondary batteries. Recently, lithium vanadium oxide, which has a layered structure, is assumed as one of the promising anode material as alternative of graphite. This material shows a high volumetric capacity, which is 1.5 times higher than that of graphite. However, relative low electrical conductivity and particle fracture, which results in the electrolyte decomposition and loss of electric contact between electrode, induce rapid capacity decay. In this report, we investigated the effect of electrolyte additive on the electrochemical characteristics of lithium vanadium oxide.

• Journal of Gastric Cancer
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• v.13 no.4
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• pp.255-262
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• 2013

Purpose: Robotic surgery for gastric cancer is a promising alternative to laparoscopic surgery, but the data are limited. We aimed to evaluate whether gaining experience in robotic gastrectomy could improve surgical outcomes in the treatment of gastric cancer. Materials and Methods: Two hundred and seven consecutive cases of patients with clinical stage I gastric cancer who underwent robotic surgery at the National Cancer Center of Korea between February 2009 and February 2012 were retrospectively reviewed. Surgical outcomes were analyzed and compared between the initial 100 and later 100 cases. Results: Seven patients required conversion to open surgery and were excluded from further analysis. The mean operating time for all patients was 248.8 minutes, and mean length of hospitalization was 8.0 days. Twenty patients developed postoperative complications. Thirteen were managed conservatively, while 6 had major complications requiring invasive procedures. One mortality occurred owing to myocardial infarction. Operating time was significantly shorter in the latter 100 cases than in the initial 100 cases (269.9 versus 233.5 minutes, P<0.001). The number of retrieved lymph nodes was significantly greater in the latter cases (35.9 versus 39.9, P=0.032). The hospital stay of patients with complications was significantly longer in the initial cases than in the latter cases (16 versus 7 days, P=0.005). Conclusions: Increased experience with the robotic procedure for gastric cancer was associated with improved outcomes, especially in operating time, lymph node retrieval, and shortened hospital stay of complicated patients. Further development of surgical techniques and technology might enhance the role of robotic surgery for gastric cancer.