• Proceedings of the Korean Vacuum Society Conference
• /
• 2010.02a
• /
• pp.362-362
• /
• 2010

Today, vast attention has been paid to periodic arrays of nanostructures due to their potential for applications such as memory with huge storage density. Such application requires large-scale fabrication of well ordered nano-sized structures. One of the most widely used methods for the ordered nanostructures is lithography. This top-down process, however, has the limit to reduce size. Here the promising alternative is the self-organization of ordered nano-sized structures such as large scale 2d carbon-induced reconstructions on W(110). In the present study, we report on the first well-resolved atomic resolution STM studies of the well-known R($15{\times}3$) and R($15{\times}12$) carbon induced reconstruction of the W(110). From the atomic image of R($15{\times}3$) for different values of tunneling gap resistance, we can tell there are no missing atoms in unit cells of R($15{\times}3$) and some atomic displacements are substantial from the clean W(110), even though not all the imaged position of atoms correspond to tungsten, but may include those of carbon. We are considering two cases; First case is related to lattice deformation, or top layer of W(110) is deformed in the process of relief of strain caused by random inserting of carbon atoms possibly in the interstitial position. In the second case, R($15{\times}3$) unit cell results from a coincidence lattice between clean W(110) substrate and tungsten carbide overlayer which has rectangular atomic arrangement and giving R($15{\times}3$) coincidence lattice. beta-W2C showing rectangular unit cell should be a candidate. Further, we report on new reconstructions. Unlike the well-known R($15{\times}12$) consisting of two parts, two inner structures between two "Backbone" structures. The new reconstruction, which we found for the first time, contains more parts between the "Backbone"s. Sometimes we can observe the reconstruction consists of only inner parts without "Backbone" parts. Thus, the observed reconstruction can be built by constructing of two types of "Lego"-like block. Moreover, the rectangle shape of "Backbone" transform to parallelogram-like shape over time, the so-called wavy-R($15{\times}12$). Adsorption of hydrogen can be the reason for this transformation.

• The Journal of the Petrological Society of Korea
• /
• v.28 no.4
• /
• pp.251-277
• /
• 2019

The Gogunsan Archipelago is composed of two island groups; the first group includes Mal-do, Myeong-do, Gwangdae-do, and Bangchuk-do islands consisting of Neoproterozoic rocks, and the second group includes Yami-do, Sinsi-do, Muneo-do, Jangja-do, and Seonyu-do islands consisting of Cretaceous rocks. The first group mainly consists of the Bangchuk formation which can be divided into two layers; the lower layer was more deformed than the upper layer. The former was intruded by mafic and felsic volcanic rocks formed in the volcanic arc tectonic setting 930-890 Ma and the latter was deposited ca. 825-800 Ma. In these islands, large scale folds with east-west fold axes were beautifully formed; the Maldo island fold was designated as natural monument and large scale beautiful chevron fold was developed on the Gwangdae-do island. In addition, there are unique zebra-shaped outcrop formed by a mixing of basic and acidic magma and Independent Gate shaped outcrop formed by coastal erosion. On the other hand, the Yami-do, Sinsi-do, Muneo-do, Jangja-do and Seonyu-do islands consist of 92-91Ma Cretaceous volcanic rocks and, in Sinsi-do island, the Nanshan formation deposited ca. 92 Ma. These Cretaceous volcanic rocks formed by melting of the continental crust by the heat supplied from the uplifting mantle due to the extension caused by a retreat of subducting ocean slab. Yami-do and Sinsi-do islands are composed of rhyolite. In Yami-do island, bands with vertical joint formed by cooling of the bottom part of the lava, are shown. In Sinsi-do island, large-scale vertical joints formed by cooling of lava flow, were developed. The Jangja-bong of Jangja-do island and Mangju-bong of Seonyu-do island are composed of brecciated rhyolite and formed a ring shaped archipelago contributing to the development of marine culture by providing natural harbor condition. They also provide beautiful views including 'Seonyu 8 views' along with other islands. As mentioned above, the Gogunsan archipelago is rich in geoheritages and associated cultural and historical resources, making it worth as a National Geopark.

• Journal of Animal Science and Technology
• /
• v.46 no.4
• /
• pp.571-584
• /
• 2004

It is known widely that granulosa cell apoptosis leads follicular atresia and macrophages exert their effects directly and/or indirectly from the initiation to the completion of follicular atresia by phagocytosis of apoptotic bodies and secretion of various cytokines. However, the site of initiation, propagation routes and the elimination methods of apoptotic bodies, and the time and methods of penetration of macrophages into the follicles are not known completely. Using pig(Yorkshire-breed) ovary, immunohistochemical studies with TUNEL for apoptotic bodies and pig macrophage monoclonal antibody 4E9 for macrophages, and light and transmission electron microscopic observations were performed. In the pig, follicular atresia began with the granulosa cell apoptosis, and the apoptosis of theca intema cells occured at the same time. The apoptosis of granulosa cells initiated randomly within the granulosa cell layer and propagated rapidly into the whole layer. Ultrastructura1ly, apoptotic granulosa cells showed characteristic pyknotic and deformed nucleus and intracytoplasmic vesicles. Apoptotic bodies were eliminated by intact granulosa cells and macrophages. Intact granulosa cells ingested apoptotic bodies transiently, soon after they fell into the apoptosis. Finally, apoptotic bodies and degenerated oocyte were phagocytosed by macrophages. Macrophages entered the ovarian follicle at the time of initiation of granulosa cell apoptosis, and migrated with the progression of apoptosis. By elimination of theca cells, macrophages contributed the completion of follicular atresia These results will provide valuable informations on the study of the interrelation between macrophage and ovarian follicular atresia.

• The Korean Journal of Petroleum Geology
• /
• v.4 no.1_2 s.5
• /
• pp.27-39
• /
• 1996

In the Cretaceous, the Gulf Coast Basin evolved as a marginal sag basin. Thick clastic and carbonate sequences cover the disturbed and diapirically deformed salt layer. In the Cretaceous the salinities of the Gulf Coast Basin probably matched the Holocene Persian Gulf, as is evidenced by the widespread development of supratidal anhydrite. The major Lower Cretaceous reservoir formations are the Cotton Valley, Hosston, Travis Peak siliciclastics, and Sligo, Trinity (Pine Island, Pearsall, Glen Rose), Edwards, Georgetown/Buda carbonates. Source rocks are down-dip offshore marine shales and marls, and seals are either up-dip shales, dense limestones, or evaporites. During this period, the entire Gulf Basin was a shallow sea which to the end of Cretaceous had been rimmed to the southwest by shallow marine carbonates while fine-grained terrigengus clastics were deposited on the northern and western margins of the basin. The main Upper Cretaceous reservoir groups of the Gulf Coast, which were deposited in the period of a major sea level .rise with the resulting deep water conditions, are Woodbinefruscaloosa sands, Austin chalk and carbonates, Taylor and Navarro sandstones. Source rocks are down-dip offshore shales and seals are up-dip shales. Major trap types of the Lower and Upper Cretaceous include salt-related anticlines from low relief pillows to complex salt diapirs. Growth fault structures with rollover anticlines on downthrown fault blocks are significant Gulf Coast traps. Permeability barriers, up-dip pinch-out sand bodies, and unconformity truncations also play a key role in oil exploration from the Cretaceous Gulf Coast reservoirs. The sedimentary sequences of the major Cretaceous reseuoir rocks are a good match to the regressional phases on the global sea level cuwe, suggesting that the Cretaceous Gulf Coast sedimentary stratigraphy relatively well reflects a response to eustatic sea level change throughout its history. Thus, of the three main factors controlling sedimentation (tectonic subsidence, sediment input, and eustatic sea level change) in the Gulf Coast Basin, sea-level ranks first in the period.

• The Korean Journal of Petroleum Geology
• /
• v.6 no.1_2 s.7
• /
• pp.8-19
• /
• 1998

In the Sinri area located at the mid western boundary of the Jinan basin, the Manduksan Formation which mainly consists of coarse sandstone narrowly intercalated with shale and the alternation of sand and shale and the Dalgil Formation mainly of shale are distributed. It consists of four lithofacies, such as coarse sandstone, interbedded sandstone/shale, shale and volcanic rock lithofacies. All sediments are interpreted to be deposited by turbidity currents and free fallouts in a lacustrine basin. In these rocks many penecontemporaneous defomation structures are observed such as fold and thrust fault at large scale, and swelling, boudin structure, flame structure, load structure, ptygmatic fold and convolute bedding at small scale. All these structures are developed between upper and lower undisturbed sedimentary strata. Two large folds are similar folds, but lower one gradually developed into concentric shape. The swelling structures by convergence of the sediments are observed in the hinge area and the boudin structures are developed in the limb. The thrust faults including minor folds and sandstone lobes show duplex structure with asymmetric and kink fold on and below in front of the detached sandstone layer. Development of the swellings, boudins and lobes indicates the flexbility of the sediments during deformational episodes. The folds and thrust faults rarely contain fractures relative their scales and lithologies. This feature also indicates the retrievability of sediments during deformation. At the flanks of the thrust faults the normal faults are formed contemporaneously. The deformation structures at small scale such as flame structures, load structures, ptygmatic folds and convolute beddings are syndepositional and penecontemporaneous, which show the effects of tectonic movements. All these deformed sedimentary structures of the Sinri area suggest the continuing tectonic movements during and/or after deposition.

• Journal of the Korean Institute of Traditional Landscape Architecture
• /
• v.36 no.3
• /
• pp.115-127
• /
• 2018

This study was attempted to find out the value of cultural assets through the clear diagnosis and prescription of the dead and weakness factors of the Population of Retusa Fringe Trees in Pyeongji-ri, Jinan(Natural Monument No. 214), The results are as follows. First, Since the designation of 13 natural monuments in 1968, since 1973, many years have passed since then. In particular, despite the removal of some of the buried soil during the maintenance process, such as retreating from the fence of the primary school after 2010, Second, The first and third surviving tree of the designated trees also have many branches that are dead, the leaves are dull, and the amount of leaves is small. vitality of tree is 'extremely bad', and the first branch has already been faded by a large number of branches, and the amount of leaves is considerably low this year, so that only two flowers are bloomed. The second is also in a 'bad'state, with small leaves, low leaf density, and deformed water. The largest number 1 in the world is added to the concern that the s coverd oil is assumed to be paddy soils. Third, It is found that the composition ratio of silt is high because it is known as '[silty loam(SiL)]'. In addition, the pH of the northern soil at pH 1 was 6.6, which was significantly different from that of the other soil. In addition, the organic matter content was higher than the appropriate range, which is considered to reflect the result of continuous application for protection management. Fourth, It is considered that the root cause of failure and growth of Jinan pyeongji-ri Population of Retusa Fringe Trees group is chronic syndrome of serious menstrual deterioration due to covered soil. This can also be attributed to the newly planted succession and to some of the deaths. Fifthly, It is urgent to gradually remove the subsoil part, which is estimated to be the cause of the initial damage. Above all, it is almost impossible to remove the coverd soil after grasping the details of the soil, such as clayey soil, which is buried in the rootstock. After removal of the coverd soil, a pestle is installed to improve the respiration of the roots and the ground with Masato. And the dead 4th dead wood and the 5th and 6th dead wood are the best, and the lower layer vegetation is mown. The viable neck should be removed from the upper surface, and the bark defect should undergo surgery and induce the development of blindness by vestibule below the growth point. Sixth, The underground roots should be identified to prepare a method to improve the decompression of the root and the respiration of the soil. It is induced by the shortening of rotten roots by tracing the first half of the rootstock to induce the generation of new roots. Seventh, We try mulching to suppress weed occurrence, trampling pressure, and soil moisturizing effect. In addition, consideration should be given to the fertilization of the foliar fertilizer, the injection of the nutrients, and the soil management of the inorganic fertilizer for the continuous nutrition supply. Future monitoring and forecasting plans should be developed to check for changes continuously.