• Title/Summary/Keyword: physical deterioration

Search Result 454, Processing Time 0.031 seconds

Effects of the Contaminants in Papermaking Process Water on Physical Properties of Paper (공정수 내의 오염물질이 종이의 물성에 미치는 영향)

  • 이학래;함충현;이지영
    • Journal of Korea Technical Association of The Pulp and Paper Industry
    • /
    • v.36 no.1
    • /
    • pp.16-23
    • /
    • 2004
  • Recently the increased concerns about the cost reduction and environmental protection make the paper industry increase the closure level of papermaking system, which results in the buildup of organic and inorganic materials in the papermaking process water. Increase of the system closure causes deterioration of additive performance and provokes diverse problems in papermaking process and product quality. To investigate the effects of process water quality on the physical properties of fine papers handsheets were prepared with process water containing various amounts of inorganic and organic contaminants including calcium or sodium ions and oxidized or cationic starches. Inorgainc and organic materials did not show any significant effect on the physical properties of handsheets. Recycled GCC showed the same trends as inorganic and organic materials. The performance of cationic starch was deteriorated, however, in the recycled white water, which resulted in the reduction of tensile index of handsheets.

The Effect of Atmospheric Conditions on the Physical and Mechanical Properties of Linerboard

  • Kim, Hyoung-Jin;Choi, Woo-Young;Um, Gi-Jeung
    • Journal of Korea Technical Association of The Pulp and Paper Industry
    • /
    • v.38 no.5 s.118
    • /
    • pp.60-65
    • /
    • 2006
  • The physical and mechanical properties of linerboard were shown to be affected by changing atmospheric conditions. Two atmospheric conditions were measured in order to investigate how they were affected by different atmospheric conditions on the physical and mechanical properties of domestic linerboard. The basis data set for the standardization research was provided in this study. It is confirmed that the relative humidity seemed to be a major factor on the quality deterioration of a linerboard. Experimental results have shown that the short span compression test (SCT) could be used to evaluate the quality characteristics of linerboardat different moisture content and relative humidity.

Material Characteristics and Deterioration Assessment of the Stone Buddhas and Shrine in Unjusa Temple, Hwasun, Korea (화순 운주사 석조불감의 재질특성과 풍화훼손도 평가)

  • Park, Sung-Mi;Lee, Myeong-Seong;Choi, Seok-Won;Lee, Chan-Hee
    • Journal of Conservation Science
    • /
    • v.24
    • /
    • pp.23-36
    • /
    • 2008
  • The stone Buddhas and Shrine of Unjusa temple (Korea Treasure No. 797) in Hwasun formed in Koryo Dynasty are unique style which the Buddha faces each other the back parts of south and north within the stone Shrine. The stone Buddhas and Shrine are highly evaluated in historical, artistic and academic respects. But, the stone properties have been exposed in the open system various aspects of degradations weathered for a long time without specific protective facilities. The rock materials of the stone Buddhas and Shrine are about 47 blocks, and total press load is about 56.6 metric ton. The host rocks composed mainly of white grey hyaline lithic tuff and rhyolitic tuff breccia. In addition, biotite granite used as part during the restoration works. The chemical index of alteration for host tuffaceous rocks and the replacement granites range from 52.1 to 59.4 and 50.0 to 51.0, respectively. Weathering types for the stone Buddhas and Shrine were largely divided with physical, chemical and biological weathering to make a synthetic deterioration map according to aspects of damage, and estimate share as compared with surface area. Whole deterioration degrees are represented that physical weathering appeared exfoliation. Chemical weathering is black coloration and biological weathering of grey lichen, which show each lighly deterioration degrees. According to deterioration degree by direction of stone Buddhas and Shrine, physical weathering mostly appeared by 39.1% on the sorthern part, and chemical weathering is 61.2% high share on the western part. Biological weathering showed 38.3% the largest distribution on the southern part. Therefore, it is necessary to try hardening for the parts with serious cracks or exfoliations, remove secondary contaminants and organisms through regular cleaning. Also necessary to make a plan to remove moisture of the ground which causes weathering, and estimate that need established and scientific processing through clinical demonstration of conservation plan that chooses suitable treatment.

  • PDF

Characteristics of Surface Deterioration and Materials for Stone Guardian and Stone Memorial Tablets from Muryeong Royal Tomb of Baekje Kingdom in Ancient Korea (백제 무령왕릉 석수와 지석의 재질 및 표면손상 특성)

  • Park, Jun Hyoung;Lee, Chan Hee;Choi, Gi Eun
    • Journal of Conservation Science
    • /
    • v.33 no.4
    • /
    • pp.241-254
    • /
    • 2017
  • The Stone Guardian and Memorial Tablets from the Muryeong Royal Tomb are composed of the same kind of plutonic igneous rocks, the so-called hornblendite. Color of the rocks show greenish gray, and both of them occurred with medium-grained granular texture. The rock-forming minerals composed mainly of amphibole and plagioclase. Magnetic susceptibility of the Stone Guardian is 0.15 to 0.63 (mean $0.42{\times}10^{-3}SI\;unit$), the King's Stone Memorial Tablet is 0.11 to 0.38 (mean $0.24{\times}10^{-3}SI\;unit$) and the Queen's Stone Memorial Tablet ranges from 0.10 to 0.33 (mean $0.18{\times}10^{-3}SI\;unit$). The rocks of the artifacts are hard to find in the Gongju area. Large scaled out crop of hornblendite is not distributed, but found in many places that the form of dike. The lithology and occurrences indicate that the artifacts are made of plutonic rock rather than dike. Reddish brown and pale brown contaminants, are also distributed on the surface of the Stone Guardian and Memorial Tablets. The reddish brown color is due to Fe oxide, and the pale brown color occurs due to the elution of Ca. The reddish brown contaminants are influenced by the internal components of the rock and oxidation of burial iron accessories. In contrast, the pale brown contaminants are considered to have flown from the carbonate materials used in the Royal Tomb, with a little added Fe oxide. Physical and chemical deterioration operate intricately in the Stone Guardian and Memorial Tablets. Physical deterioration is extremely rare and chemical deterioration is stable except for a part of the Stone Guardian and the front of the Queen Stone Memorial Tablet.

Comparisons of Effectiveness of the Supercritical Fluid Extraction Dewaxing on the Beeswax-Treated Paper with Different Aging Degrees (열화율이 상이한 밀랍지의 초임계유체추출 탈랍처리효과 비교분석)

  • Jeong, Hye Young;Kang, Young Suk;Go, In Hee;Yang, Eun Jeong;Choi, Kyoung Hwa
    • Journal of Korea Technical Association of The Pulp and Paper Industry
    • /
    • v.46 no.6
    • /
    • pp.56-62
    • /
    • 2014
  • This study aims to investigate the applicability of supercritical fluid extraction as a dewaxing technique to restore the beeswax-treated volume of the Annals of the Joseon Dynasty in various deterioration and damage conditions. Thus, this study analyzed the dewaxing efficiency and changes in physical and morphological properties before and after dewaxing, by applying the optimal supercritical fluid extraction dewaxing condition ($70^{\circ}C$, 40 MPa, $CO_2$, Co-solvent 20% DCM, 2 hour) to 3 kinds of beeswax-treated paper with different deterioration rates (dry artificial aging of 10, 20 and 30 days at $120^{\circ}C$). After dry artificial aging at $120^{\circ}C$ for 30 days, the average molecular weight of the beeswax-treated specimen was $1.856{\times}10^5g/mol$, showing deterioration about 80% of the beeswax-treated paper before dewaxing. It was a similar level to the molecular weight of the bees-waxed volume of the Annals of the Joseon Dynasty that has a higher degree of damage. As a result of analyzing the dewaxing efficiency through FT-IR analysis, this study discovered that it was possible to effectively dewax beeswax-treated paper in the range of deterioration 20 to 80% with this supercritical fluid extraction dewaxing technique applied. As a result of analyzing changes in the physical and morphological properties before and after dewaxing, the viscosity tended to decrease to a slight degree, and since no morphological deformation or damage of stencil fibers was found, it was concluded possible to conduct stable dewaxing through this supercritical fluid extraction technique.

The Effect of Sitting Postures on Spinal Pelvic Curvature and Trunk Muscle Activation in Low Back Pain (요통 환자에서 앉은 자세가 척추 만곡과 체간 근 활성화에 미치는 영향)

  • Choi, Moon-Seok;Chung, Yi-Jung;Jeon, Hye-Won
    • Physical Therapy Korea
    • /
    • v.16 no.2
    • /
    • pp.31-39
    • /
    • 2009
  • This study is performed to investigate the difference of the spinal stability system with and without low back pain. There were 9 participants with low back pain and 9 asymptomatic subjects to be recruited, they were measured thoracic and lumbar curvature, trunk muscle activation in upright sitting postures and slump sitting, back muscle endurance, and lumbar proprioception. Spinal curvature and surface electromyography of 4 trunk muscles were measured in an upright sitting postures and slump sitting in 18 subjects. The result of the study was that there were significant differences between the groups in spinal curvature (p<.05), significantly higher external oblique activity and less internal oblique in the low back pain group than the healthy subjects (p<.05), and significantly less proprioception in the low back pain group (p<.05). But there was not a significant difference between the trunk muscle endurance groups. According to the result, the low back pain group had greater thoracic extension and higher global muscle activity in the upright sitting posture and less proprioception. This study was useful to suggest postural training for normal muscle activation, selective muscle strengthening to prevent chronic deterioration, and helpful in making a treatment plan to indicate a synthetic care method that includes increasing proprioception.

  • PDF

Correlations between the Respiratory Function and Cervical and Lumbar Range of Motion in Elderly People

  • Park, Du-Jin;Kim, Jun-Seok;Hwang, Young-In
    • Journal of the Korean Society of Physical Medicine
    • /
    • v.16 no.3
    • /
    • pp.29-36
    • /
    • 2021
  • PURPOSE: The respiratory function and range of joint mobility deteriorate due to aging, respectively, and the respiratory function may be related to the range of joint mobility. To the best of the authors' knowledge, there has been little research on how the deterioration of the range of joint mobility caused by aging is related directly to the respiratory function. This study investigated the relationship between the respiratory function and the range of joint motion in the cervical and lumbar regions of older adults. METHODS: Thirty-two older adults participated in the study. The forced vital capacity (peak expiratory flow: PEF and forced expiratory volume in 1 second: FEV1) and the range of cervical joint motion were assessed in all subjects. The results were analyzed using the Pearson's correlation coefficient. RESULTS: The respiratory function moderately correlated with age. A moderate correlation was observed between FEV1 and right cervical lateral flexion. PEF was moderately correlated with the lumbar lateral flexion. In addition, FEV1 correlated strongly with lumbar lateral flexion. CONCLUSION: The respiratory function was correlated with the cervical and lumbar lateral flexion. Therefore, rehabilitation of the respiratory function should involve improving the limited range of motion of the joints, and a stretching program is needed for older adults.

A systematic literature review on the effects of physical functions on braking ability of elderly drivers (고령운전자의 제동능력에 미치는 신체적 기능에 대한 체계적 문헌고찰)

  • Jaeseok, Heo;Sangyeol, Lee;Sungyoung, Yoon;Seunghoon, Lee;Him, Seok
    • Journal of Korean Physical Therapy Science
    • /
    • v.29 no.4
    • /
    • pp.43-53
    • /
    • 2022
  • Background: It is suggested that the decline in functional level due to aging influences the increase in traffic accidents among elderly drivers. Among the functions related to the driving behavior of older drivers, physical function is related to muscle strength and motor control, and aging causes deterioration of motor control and a defect in motor output variability. Method: Data Search The online databases used for literature search are PubMed, ProQuest(PML), NDSL, and literature searches were conducted from April 19 to April 26, 2022. For the search, 'aging', 'driving', and 'braking' were used in the investigation. Results: The physical functions related to the braking ability of elderly drivers were analyzed in muscle strength, reaction ability, motor control, and other related factors. In terms of muscle strength, 3 studies analyzed the above factors. 8 studies analyzed the above factors for response ability. For motor control, two studies analyzed the above factors. In addition, related factors were analyzed in one piece. Conclusion: As a result of the analysis, physical function for reaction ability showed the highest frequency, followed by the strength item with the highest frequency. This study suggests that factors that can increase physical function must be included in the development of a rehabilitation program for the driving ability of the elderly.

Detailed Deterioration Evaluation and Analysis of Conservation Environment for the Seosanmaaesamjonbulsang (Rock-carved Triad Buddha in Seosan), Korea (서산마애삼존불상의 정밀 손상도 평가와 보존환경 분석)

  • Lee, Sun-Myung;Lee, Chan-Hee;Kim, Ji-Young
    • Journal of Conservation Science
    • /
    • v.26 no.3
    • /
    • pp.277-294
    • /
    • 2010
  • The Seosanmaaesamjonbulsang (National Treasure No. 84) consists of light gray and coarse to mediumgrained biotite granite with partly developed pegmatite and quartz vein. The host rock is divided into dozens of rock blocks with various shape along irregular discontinuity plane. The evaluation results of discontinuity systems reveal that the host rock were exposed to instable sloping environments. Results of deterioration diagnosis show that the degree of damage has been made worse by physical weathering and surface discoloration laying stress on part that vertical and horizontal joints are massed. Generally, deterioration rate of the triad Buddha surface cover with 42.7%, however, the rate of physical weathering and surface discoloration are subdivided to 9.6% and 33.1%, respectively. Ultrasonic measurements indicate that the triad Buddha was reached highly weathered grade in general. And the rock material was weaken to show low velocity zone of 1,000m/s along irregular joint systems. Indoor and outdoor mean relative humidity of the shelter was recorded more than 70% during every season, and high frequency appears in high relative humidity range over 95%. Such environments seem to have produced dew condensation on the rock surface with rainfall and supply water, promoted physical, chemical and biological weathering along crack and joint, resulting in high permeation of water and percentage of water content. Therefore, it is judged that for scientific conservation of the triad Buddha it needs environment control through persistent preservation environment monitoring including water problem.

Quantitative Deterioration Assessment and Microclimatic Analysis of the Gyeongju Seokbinggo (Ice-storing Stone Warehouse), Korea (경주석빙고의 정량적 훼손도 평가와 미기후환경 분석)

  • Kim, Ji-Young;Lee, Chan-Hee;Lee, Myeong-Seong
    • Journal of Conservation Science
    • /
    • v.25 no.1
    • /
    • pp.25-38
    • /
    • 2009
  • The Gyeongju Seokbinggo (Treasure No. 66) is an ice-storing stone warehouse, consisting mainly of alkaligranite which shows milky white color and medium-grained textures with drusy cavities. As results of deterioration assessment, the deterioration rates were determined as crack (12.5%), disjoining (6.7%), breaking-out (25.1%), exfoliation (20.9%), efflorescence (6.5%), brown discoloration (9.8%), darkgray discoloration (2.0%) and biological discoloration (36.5%). Comprehensive physical deterioration rate and discoloration rate were calculated as 43.7% and 68.7%, respectively, that indicates the Seokbinggo has been severely weathered. Indoor relative humidity was above 90% except in winter season. Indoor microclimate was hardly fluctuating although indoor microclimate was dependent on the outdoor climate. The main cause of deterioration was high relative humidity and a long time of wetness due to penetration of rain, underground water and condensation. It was identified that the water brought out biological discoloration, dissolution of minerals, structural movement and efflorescence, and the dust from the ground soil in front of the entrance accelerated brown and dark gray discoloration on the stone surface.

  • PDF