• Korean Journal of Materials Research
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• v.34 no.5
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• pp.223-234
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• 2024

This review explores the potential of pillared bentonite materials as solid acid catalysts for synthesizing diethyl ether, a promising renewable energy source. Diethyl ether offers numerous environmental benefits over fossil fuels, such as lower emissions of nitrogen oxides (NO_x) and carbon oxides (CO_x) gases and enhanced fuel properties, like high volatility and low flash point. Generally, the synthesis of diethyl ether employs homogeneous acid catalysts, which pose environmental impacts and operational challenges. This review discusses bentonite, a naturally occurring alumina silicate, as a heterogeneous acid catalyst due to its significant cation exchange capacity, porosity, and ability to undergo modifications such as pillarization. Pillarization involves intercalating polyhydroxy cations into the bentonite structure, enhancing surface area, acidity, and thermal stability. Despite the potential advantages, challenges remain in optimizing the yield and selectivity of diethyl ether production using pillared bentonite. The review highlights the need for further research using various metal oxides in the pillarization process to enhance surface properties and acidity characteristics, thereby improving the catalytic performance of bentonite for the synthesis of diethyl ether. This development could lead to more efficient, environmentally friendly synthesis processes, aligning with sustainable energy goals.

• Animal Bioscience
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• v.37 no.4_spc
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• pp.786-793
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• 2024

Latin America is a culturally, geographically, politically, and economically diverse region. Agriculture in Latin America is marked by a remarkable diversity of production systems, reflecting various agroecological zones, farm sizes, and technological levels. In the last decade, the swine industry increased by 30.6%, emerging as a great contributor to food security and economic development in Latin America. Brazil and Mexico dominate the pig production landscape, together accounting for 70% of sow inventory in the region. The swine industry in Latin America is predominantly comprised of small and medium-sized farms, however, in the past 30 years, the number of pig producers in Brazil dropped by 78%, whereas pork production increased by 326%. Similar to the global pork industry, the growing demand for pork, driven by population growth and changing dietary habits, presents an opportunity for the industry with an expected growth of 16% over the next decade. The export prospects are promising, however subject to potential disruptions from global market conditions and shifts in trade policies. Among the challenges faced by the swine industry, disease outbreaks, particularly African Swine Fever (ASF), present significant threats, necessitating enhanced biosecurity and surveillance systems. In 2023, ASF was reported to the Dominican Republic and Haiti, Porcine Reproductive and Respiratory Syndrome (PRRS) in Mexico, Costa Rica, the Dominican Republic, Colombia, and Venezuela, and Porcine Epidemic Diarrhea (PED) in Mexico, Peru, the Dominican Republic, Colombia, and Ecuador. Additionally, feed costs, supply chain disruptions, and energy expenses have affected mainly the smaller and less efficient producers. The swine industry is also transitioning towards more sustainable and environmentally friendly practices, including efficient feed usage, and precision farming. Ensuring long-term success in the swine industry in Latin America requires a holistic approach that prioritizes sustainability, animal welfare, and consumer preferences, ultimately positioning the industry to thrive in the evolving global market.

• Korean Journal of Materials Research
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• v.34 no.3
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• pp.152-162
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• 2024

In this study, we introduce a novel TiN/Ag embedded TiO₂/FTO resistive random-access memory (RRAM) device. This distinctive device was fabricated using an environmentally sustainable, solution-based thin film manufacturing process. Utilizing the peroxo titanium complex (PTC) method, we successfully incorporated Ag precursors into the device architecture, markedly enhancing its performance. This innovative approach effectively mitigates the random filament formation typically observed in RRAM devices, and leverages the seed effect to guide filament growth. As a result, the device demonstrates switching behavior at substantially reduced voltage and current levels, heralding a new era of low-power RRAM operation. The changes occurring within the insulator depending on Ag contents were confirmed by X-ray photoelectron spectroscopy (XPS) analysis. Additionally, we confirmed the correlation between Ag and oxygen vacancies (V_o). The current-voltage (I-V) curves obtained suggest that as the Ag content increases there is a change in the operating mechanism, from the space charge limited conduction (SCLC) model to ionic conduction mechanism. We propose a new filament model based on changes in filament configuration and the change in conduction mechanisms. Further, we propose a novel filament model that encapsulates this shift in conduction behavior. This model illustrates how introducing Ag alters the filament configuration within the device, leading to a more efficient and controlled resistive switching process.

• Journal of the Korean Institute of Gas
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• v.28 no.2
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• pp.17-23
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• 2024

As interest in sustainable and eco-friendly energy increases due to various problems in the carbon economy, a hydrogen economy that utilizes hydrogen as a main energy source is emerging. Among the methods of producing hydrogen, the water electrolysis method based on renewable energy produces environmentally friendly green hydrogen because it produces hydrogen from water. The water electrolysis facility currently under development produces hydrogen by receiving electricity directly from renewable energy and uses KOH(potassium hydroxide) as an electrolyte. In this study, HAZOP(Hazard and Operability Study), a qualitative risk assessment, was conducted on alkaline water electrolysis facilities to find problems and risk factors in the design and operation of water electrolysis facilities. Risks related to oxygen and KOH, an electrolyte, were identified as major risks, and it is believed that the safety of facilities and workers can be secured based on emergency action plans and safe operation procedures.

• Journal of Environmental Science International
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• v.33 no.8
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• pp.575-581
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• 2024

Insect pests are a significant threat to stored crops and can lead to considerable economic losses and reduced crop quality. Traditional pest control methods often involve chemical treatments, which have adverse environmental and health effects. This study evaluated the effectiveness of controlling the environment using LED lighting and plant-derived odor barriers as a dual strategy for insect pest control. The storage environment was altered using LED lights that emitted specific wavelengths (580-585 nm) and by reducing other wavelengths (300-500 nm). This light environment was combined with an insect odor barrier derived from Cinnamomum verum, Illicium verum, and Artemisia annua, and their duel impact on the behavior and frequency of insect pests under real storage conditions was determined. The findings revealed significant changes in the frequencies of various insect orders, indicating differential responses to light wavelengths and odor barriers. Notably, the introduction of an anti-insect light and odor barrier environment reduced Diptera and Hemiptera frequencies, which could potentially reduce pest intrusion. The results underscore the potential use of integrated light and odor barriers as a noninvasive and environmentally friendly approach to pest management. This study identifies the specific wavelengths and odor combinations that effectively deter insect pests and contribute to the development of more efficient and sustainable pest control methods. It also highlights the importance of understanding insect behavior and frequency changes in response to novel deterrent strategies.

• Advances in materials Research
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• v.13 no.4
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• pp.269-283
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• 2024

Biocompositesmade up of starch and jute fibres are biodegradable and environmentally friendly materials for sustainable development. In this study, corn starch has been separately modified with 15% pine rosin and 40% glutaraldehyde, and 30% glycerol is used as a plasticizer. The composites have been prepared for three different volume proportions of matrix and jute fibre such as 60:40, 70:30 and 80:20 by using a hot compression moulding machine. The effects of pine rosin and glutaraldehyde on mechanical properties have been studied. Pine rosin modified starch jute composites have shown higher tensile and flexural properties as compared with glutaraldehyde modified starch jute composite. The highest tensile strength and modulus are found at 60:40 matrix and jute fibre volume proportion of pine rosin modified starch jute composite which are 13.97 MPa and 782.94 MPa respectively. Similar trends were found in flexural strength and modulus for pine rosin modified starch jute composite having matrix to jute fibre proportion 60:40 which are 29.18 MPa and 1107.76 MPa respectively. But, in case of impact strength, glutaraldehyde modified starch jute composite having matrix to jute fibre proportion 80:20 have shown highest impact strength that is 59.05 KJ/m². Starch-jute composite with glutaraldehyde shows 33% more water absorbency as compared to composite having pine rosin as cross linker. Highest FTIR graph indicates that the number of -OH group is much lower in case of pine rosin modified starch than glutatraldehyde modified starch which indicates that bonds formed by pine rosin are much stronger than the bonds formed by glutaraldehyde. The surface morphology of the composite was influenced by pine rosin and glutaraldehyde which is shown in the SEM image.

• Korean Journal of Environment and Ecology
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• v.22 no.3
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• pp.207-220
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• 2008

Tourism in the natural environment grows significantly and in many tropical countries it becomesthe important earning of the nations. Nevertheless, tourism impact to environment and cultural values has become the threats to the sustainability and competitiveness of such industry. Therefore, the appropriate planning and management of tourism destination sites where environmentally and culturally fragile are needed in order to increase economic benefits, sustain local culture and conserve environment in balance. The aims of the paper are to examine tourism practices, to determine socio-cultural and natural resources, and to assess local people perception to cultural landscape and its future tourism development in order to formulate the appropriate strategies to achieve sustainable tourism. A case study was carried out at Tengger highland, Bromo Tengger Semeru National Park(BTSNP) East Java. Official documents were gathered and interviews with several key persons had conducted to determine recent status of tourism, resources capital and the existence of local people. Semi-structured interviews and questionnaires were carried out at Tenggerese villages to explore local people perspectives to tourism development, culture preservation, and cultural landscape conservation issues. It is followed by descriptive analysis of vegetation to assess the recent status of environments based on vegetation information. Our findings reveals that tourism grows significantly at BTSNP, and Tengger Caldera as spiritual and cultural sites for local people become the centre for tourism activities. The abundance cultural and natural resources are the significant capital for sustainable tourism. Tenggerese argues that tourism should be planned to provide benefits to local people, preserve tradition and able to conserve nature in order to ensure the living sustainability of Tenggerese. The overall result of the study provide general feature of recent status of the cultural and natural resources as well as positive society perception in order to establish a strategy for sustainable tourism in cultural landscape.

• Archives of design research
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• v.18 no.4 s.62
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• pp.105-118
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• 2005

Housing environment for human beings has been diversified and more convenient due to the development of high technology and civilization brought by industrialization in the 20th century. In the 21st century, how to overcome the ecological limit of biased development-centered advancement, that is, how to preserve and hand over a clean and healthy 'sustainable environment' to our next generations has been one of the most-talked about issues. Environmental symbiosis means a wider range of environmental harmony from micro-dimensional perspective to macro one. The three goals of a environmentally friendly house are to preserve global environment, to harmonize with the environment around, and to offer a healthy and comfortable living environment. From the point of view of environmental symbiosis, houses should be designed to save energy and natural resources for preservation of global environment, to collect such natural energy resources as solar heat and wind force, to recycle waste water, and recycle and reduce the amount of the waste matter. Now, the environmentally-friendly house became a new social mission that is difficult to not only challenge but also realize without conversion to a new paradigm, ecologism.

• Journal of the Korean Association of Geographic Information Studies
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• v.12 no.4
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• pp.34-47
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• 2009

Rapid urbanization is causing environmental and ecological damage, development thoughtless for the environment, and social and economical issues. It is important to grasp urban growth situations and characteristics, reflect them, and establish a policy for the solution of issues pursuant to urbanization and the sustainable and efficient development of national land. This research aims to be used as basic data in establishing an urban policy by analyzing the situations and characteristics of urban growth for the past 20 years in our entire country rather than an existing district. For this, some urban districts were sampled using a 1980s and 2000s version of land cover map produced by Ministry of Environment, and then pattern analysis for urban growth by administrative district ranks was conducted using GIS and a statistical technique. As a result, the development zone area after 1980s has increased by 2.5 times as compared to that before 1980s, and especially in the farm villages neighboring the national capital region, it has increased by 21.2 times. Special cities and metropolitan cities were developed at the districts being low in altitude, close to the principal road and the major downtown, high in road ratio, and restricted environmentally, ecologically and legally, and were diverted from mountains, forests and grassland to urban land. On the other hand, farm villages neighboring a large city, farm villages neighboring the national capital region, and local farm villages were developed at the districts being high in altitude, far from the principal road and the major downtown, low in road ratio, and not restricted environmentally, ecologically and legally, and were diverted from farmland to urban land. That is, it can be seen that urban development has been actively realized despite the unfavorable topographical conditions in the suburban districts due to lack of available land and various regulations and policies as urban growth around big cities expands.

• Journal of the Korean association of regional geographers
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• v.11 no.5
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• pp.349-367
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• 2005

The purpose of this paper is to establish three themes of regional instruction based on new regional geography and to examine explanation of space, understanding of place and judgement of environmental values for the Jinju regional instruction. Under the premise that region is the representation of space, place, and environmental perception, we reviewed location and space, event and place, development and environmental values in Jinju area. The results of the study are as follows: Owing to locational conditions, commercial agriculture, industrial and agroindustrial park, bio industry have been developed in Jinju. There are however some tasks that have to be solved such as rural investment, industrial park relocation and economic reconstruction. The Jinju castle combat, Farmers' resistance in 1862, Human right campaign for butchers in 1923, and educational conflict all occurred in the Jinju community. These events resulted in the integration and separation of the stratified citizens. They were represented as a variety of semiotics and landscape in the place. Citizens who live in Jinju are confronted with judging the environmental values. They ask whether inviting companies to town will ensure environmentally sound and sustainable development. The regional characteristics of knowledge, culture and environment in Jinju have been reproduced through the economic activity, place understanding, place marketing, and citizens' campaign.