• 한국초지조사료학회지
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• 제11권2호
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• pp.108-115
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• 1991

A field experiment was conducted to evaluate the effects of cattle compost application on the change of soil physical properties and their relationship to yield performance of selected main forage crops. Maize(CV. Suweon 19) and sorghum hybrids(CV. Pioneer 9'31) as a summer crops and winter rye were grown on newly reclaimed red yellow soils(Fine loamy, Typic Hapludults) under different application rate of cattle compost associated with chemical NPK fertilization, from Oct. 1986 to Sept. 1989. Experimental field was laid down as a split plots design with four replications. The results obtained are summarized as follows: 1. Cattle compost application reclaimed soil physical propeties, such as formation of granular structure and water holding capacity, and it result in a great increase of plant growth and the rate of dry matter accumulation. 2. While cattle compost treatment reduced the portion of soild phase of the three phase constituents of soils, it increased the portion of air phase and liquid phase comparatively. 3. Organic matter, N, P, K, and mineral content in soil were markedly increased in the plot treated with compost. 4. Cattle compost application increased fodder production both in maize-rye and sorghum hybrids-rye cultivation. Annual dry matter yield of maize-rye cropping was 2183(NI'K only), 2425(NPK+compvst 3000 kg) and 2800kg/lOa(NPK + compost 6000kg/10a).

• Ocean and Polar Research
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• 제25권4호
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• pp.653-662
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• 2003

Changes in the area of geo-ecosystem $(62^{\circ}09'S,\;58^{\circ}31'w)$ reflect climatic changes in the South Shetland Islands. Air temperature and deglaciation will increase. The ice-free space area at the SSSS 8- (ASPA 121) site has enlarged threefold during the last 21 years, thus creating conditions for inhabitation and succession. Wind, water and snow play important roles in transportation of geochemical components. They distribute nutrients, mineral substances, seeds, fragments of plants and animals, etc. Plant and animal colonization is patchy and it happens at random in an 'island' - like manner. The colonization pattern is dependant, to a high degree on physical factors. The newly uncovered ice-free areas are at first inhabited by a vascular plant known as the Deschampsia antarctica. The border of the land-oasis with Admiralty Bay is the place where the processes related to animal feeding at the sea and reproduction on the land take place. Bird colonies and pinniped lairs form centers of fertilization surrounded by high chemical gradients dependent on the direction of the flow of nutrients $(e.g.\;NH_4)$. During the last 25 years, the numbers of penguins in this region have decreased, and thus the amount of materials excreted on land has diminished. The numbers of fur seals change in multi-annual cycles, and their migration into this area is related to the E1 $Ni\~{n}o$ phenomenon. The numbers of elephant seals in the area did not change. Organic matter deposited by the sea onto the shore are a source of nutrients and deficient chemical elements on land. Mineral matter is washed out into the waters of Admiralty Bay. These processes change seasonally, and multi annually. Negative effects on the environment at Arctowski Station induced by man are slight, but noticeable nevertheless. Physical processes have the largest influence on the living conditions and distribution of plants and animals, and as a consequence, on the functioning of the geo-ecosystem in the coastal-shore zone of the Maritime Antarctic.

• Weed & Turfgrass Science
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• 제6권3호
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• pp.222-234
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• 2017

전세계적으로 해양녹조 대발생(green tide)은 해양생태계에 큰 위협이 되고 있으며 주로 갈파래과의 Ulva 속 식물이 대부분을 차지하고 있다. 본 연구에서는 구멍갈파래(Ulva australis, ULAUS) 사멸에 미치는 여러 물리화학적 요인들의 영향 정도를 조사하여 향후 갈파래 대발생 경감기술 확립을 위한 기초자료를 얻고자 제반 실험을 수행하였다. 순수에 8시간 침지는 아무런 영향을 받지 않았으나 염도 1.0-1.5% 수준에서 7일간의 저염화 처리는 ULAUS 포자 유출을 약 70% 경감시키는 효과가 있었다. 건조처리에 의해 초기 생체중의 40-50% 이상이 감소되면 심각한 생육 장해가 일어났다. 온도처리의 경우, ULAUS는 $30^{\circ}C$ 이상부터 생육에 심각한 영향을 받았으며 $35^{\circ}C$처리에서는 배양개시 1일만에 95% 이상 고사되었고, $40^{\circ}C$, $45^{\circ}C$, $50^{\circ}C$ 처리에서 엽절편이 90-95% 고사되는데 소요되는 처리시간은 각각 10분, 30초, 1초 이었다. pH 6 이하의 조건은 ULAUS 생육을 현저히 억제하였으며 pH 4에서는 신속히 사멸되었다. 한편 ULAUS 생육을 저해하는 10여종의 화학물질을 선발하였고 이들 중 구멍갈파래를 보다 신속히 사멸시킬 수 있는 화합물은 과산화수소를 비롯한 산화제들이었다. 이들의 결과를 종합해 볼 때, 갈파래 대발생제어에 저염화, 건조, 온도 및 화합물 처리 등이 실용화 기술개발에 동원될 수 있을 것 같았고, 이중에서 온도와 화합물 요인을 적절히 활용할 경우 보다 유용한 갈파래 발생제어 효과를 거둘 수 있을 것으로 전망되었다.

• 한국대기환경학회지
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• 제23권6호
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• pp.718-726
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• 2007

There are many varieties of asbestos: chrysotile, crocidolite, amosite, tremolite, actinolite, and anthophylite. These are widely used in construction materials, brake lining, textile, and so on. Even though non-asbestos fibers such as glassfiber and rockwool have manufactured because asbestos causes asbestosis, lung cancer, mesothelioma, etc., some bad effects of non-asbestos have been also reported. PCM (phase contrast microscopy) and PLM (polarized light microscopy) have been used to qualitatively analyze asbestoses. These techniques have serious drawbacks when identifying and separating various asbestoses. Recently scanning electron microscopy (SEM) equipped with energy dispersive X-ray analysis (EDX) has been known as an useful tool to analyze airborne particle since it provides physical and chemical information simultaneously. The purpose of the study was to classify both asbestos and non-asbestos fibers and finally to develop their source profiles by using the SEM/EDX. The source profiles characterized by 6 different types of asbestos fibers and 2 types of non-asbestos fibers had been developed by analyzing a total of 380 fibers. Analytical parameters used in this study were length, width, aspect ratio, and shape as physical information, and Na, Mg, Al, Si, K, Ca, Cr, Mn, Fe, and Cu as chemical information. All the parameters were intensively reviewed.

• Bulletin of the Korean Chemical Society
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• 제34권11호
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• pp.3301-3306
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• 2013

This paper aims to address the cellular toxicity of ultra-pure titanium dioxide ($TiO_2$) and zinc oxide (ZnO) nanoparticles (NPs) frequently employed in sunscreens as inorganic physical sun blockers to provide protection against adverse effects of ultraviolet (UV) radiation including UVB (290-320 nm) and UVA (320-400 nm). In consideration that the production and the use of inorganic NPs have aroused many concerns and controversies regarding their safety and toxicity and that microsized $TiO_2$ and ZnO have been increasingly replaced by $TiO_2$ and ZnO NPs (< 100 nm), it is very important to directly investigate a main problem related to the intrinsic/inherent toxicity of these NPs and/or their incompatibility with biological objects. In the present study, we took advantage of the laser-assisted method called laser ablation for generation of $TiO_2$ and ZnO NPs. NPs were prepared through a physical process of irradiating solid targets in liquid phase, enabling verification of the toxicity of ultra-pure NPs with nascent surfaces free from any contamination. Our results show that $TiO_2$ NPs are essentially non-poisonous and ZnO NPs are more toxic than $TiO_2$ NPs based on the cell viability assays.

• 한방안이비인후피부과학회지
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• 제20권2호통권33호
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• pp.132-141
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• 2007

Objectives : The purpose of this study is to consider the definition, history, classification and clinical effect of balneotherapy. Methods : We researched oriental documents and recent sources of balneotherapy. Results and Conclusions : 1. Balneotherapy is medical cure method which uses physical chemistry effects of water. 2. Records of balneotherapy are seen in oriental documents such as Hwangjenaegyeong(黃帝內經), Sinnongbonchogyeong(神農本草經), Jaebyoungwonhuron(諸病源候論), Youmoonsachin(儒門事親), Bonchogangmok(本草綱目) and Donguibogam(東醫寶鑑) etc. 3. Spa can classify eleven types according to ingredient. The types were as following. Simple thermal spirng, Common salt spring, Sodium bicarbonated spring, Sulfate spring, Radioactive spring, Acid spring, Sulfur spring, Carbon dioxide spring, Iron spring, Alum spring & Sulfate-iron spring, Bicarbonatealkaline spring. 4. Physical, chemical and environmental effect of spa therapy have effectiveness on the chronic and we akness disease more than acute disease. And balneotherapy have more effectiveness on digestive disease, pulmonary disease, metabolic disease, circulatory disease, muscle skeletal disease and dermatologic disease than any other diseases.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 제36회 하계학술대회 논문집 C
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• pp.1862-1864
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• 2005

Carbon nanotubes [CNTs] are grown on TiN-coated Si substrates at $700^{\circ}C$ by inductively coupled plasma-chemical vapor deposition (ICP-CVD). Pre-treatment of Ni catalysts has been performed using an RF magnetron sputtering system. Structural properties and field-emission characteristics of the CNTs grown are analyzed in terms of the RF power applied and the treatment time used in the pre-treatment process. The characterization using various techniques, such as FE-SEM, AFM, and Raman spectroscopy, show that the physical dimension as well as the crystal quality of CNTs are changed by pre-treatment of Ni catalysts. It is also seen that Ni catalysts with proper grain size and uniform surface roughness may produce much better electron emission. The physical reason for all the measured data obtained are discussed to establish the relationship between the structural property and the electron emission characteristic of CNTs.

• Membrane and Water Treatment
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• 제11권1호
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• pp.1-10
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• 2020

An understanding of particle-particle interactions in filtration requires studying the detachment as well as the attachment of nanoparticles. Nanoparticles captured in a granular media filter can be released by changing the physicochemical factors. In this study, the detachment of captured silver nanoparticles (AgNPs) in granular media filtration was examined under different ionic strengths, ion type, and the presence or absence of natural organic matter (NOM). Filtration velocity and ionic strength were chosen as the physical and chemical factors to cause the detachment. Increasing filtration velocity caused a negligible amount of AgNP detachment. On the other hand, lowering ionic strength showed different release amounts depending on the background ions, implying a population of loosely captured particles inside the filter bed. Overall detachment was affected by ionic strength and ion type, and to a lesser degree by NOM coating which resulted in slightly more detachment (in otherwise identical conditions) than in the absence of that coating, possibly by steric effects. The secondary energy minimum with Na ions was deeper and wider than with Ca ions, probably due to the lack of complexation with citrate and charge neutralization that would be caused by Ca ions. This result implies that the change in chemical force by reducing ionic strength of Na ions could significantly enhance the detachment compared to that caused by a change in physical force, due to a weak electrostatic deposition between nanoparticles and filter media. A modification of the 1-D filtration model to incorporate a detachment term showed good agreement with experimental data; estimating the detachment coefficients for that model suggested that the detachment rate could be similar regardless of the amount of previously captured AgNPs.

• 한국식품저장유통학회지
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• 제12권3호
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• pp.292-298
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• 2005

발효식품 담금 용기로 사용되고 있는 유리, polypropylene(PP), polyethylene terephthalate(PET), 스테인레스 용기, 옹기에 고추장을 담아 $30^{\circ}C$에서 4개월 동안 발효하는 동안 물리적, 화학적, 미생물적인 품질변화를 측정하여 담금 용기의 효과를 비교 평가하였다. 높은 기공성을 가진 옹기는 다른 용기에 비해 전체 발효기간에서 높은 호기성 세균수, 젖산균수, 효모수를 보여서 가장 왕성한 발효진행을 보였으며, 이와함께 높은 protease 활성을 유지시키고, 아미노태 질소와 유리 아미노산을 생산하였다. 아울러 옹기에 담금 한 고추장에서는 높은 총산함량과 낮은 pH를 얻게 하였으며, 환원당도 많이 생성시켰다. 이러한 변화는 발효 $2{\sim}3$개월에 완성되어졌다. 하지만 높은 기공성에도 불구하고 옹기에서 발효된 고추장은 타용기구에 비해서 수분손실과 염도상승은 현저하지 않았는데, 이는 시간의 경과에 따라 옹기벽면에서의 기공이 고추장 성분에 의하여 일부 닫혀짐에 의한 것으로 해석된다. 이러한 성분변화의 결과로 인하여 옹기에서 발효된 고추장은 관능적인 품질에서 타 용기처리구에 비해 유의적으로 우수하였다.

• Asian Pacific Journal of Cancer Prevention
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• 제15권16호
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• pp.6721-6726
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• 2014

Background: The aim of this preliminary study was to address variations of responses observed with different starting tumor sizes of 10 and 15 mm, and the effects of different doses of tamoxifen (TAM) on experimental rat mammary tumors. Materials and Methods: Thirty-five inbred female Sprague Dawley rats aged 43 days were administered with three weekly doses of N-methyl-N-nitrosourea (NMU) intraperitoneally (ip) at 50 mg/kg body weight. Animals were randomized (beginning from 10 mm tumor size) into four TAM-treated (50, 100, 200 and $500{\mu}g/day$) groups of six animals each, and another group (n=6) treated with TAM $100{\mu}g/day$ at starting tumour size of 15 mm. The animals were treated by oral gavage daily for 8 weeks before sacrifice. Results: Serum urea and creatinine, and overall physical tumor burden were significantly modulated in animals treated with variable doses of TAM compared to the untreated controls (n=5). Final body weight and tumor number were significantly different in the 10 mm-treated animals compared to those treated at 15 mm. There were no significant differences in histopathological features among all the groups. Conclusions: Our findings suggest the importance of standardizing tumour size and drug doses before initiation of treatment, particularly in the direct comparison of basic end-tumour physical parameters.