• Title/Summary/Keyword: folding strength

Search Result 117, Processing Time 0.028 seconds

PREPERATION OF AMPHOTERIC STARCHS AND STUDY ON WET END CHEMISTRY IN PAPERMAKING

  • Shan, Chen-Fu;Su, Xie-Lai;Yi, Wang-Hai;Quan, Long-Yan
    • Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
    • /
    • 1999.04b
    • /
    • pp.386-389
    • /
    • 1999
  • Amphoteric polymers have brought to papermakers' attention gradually. In this paper, a series of amphoteric starches with different cationic and anionic degree of substitution (DS) are prepared. Better product has been selected and used under different condition. As retention and drainage aids, amphoteric starches were used in shorter fiber length, weak strength and poor drainage bleached AQ-Soda wheat straw pulp. In neutral and alkaline papermaking system, when amphoteric starches contain 0.024-0.026 anionic degree of substitution (DS), it is shown that the higher the cationic degree of substitution (DS) in amphoteric starches, the better the filler retention. The filler retention is improved 12.5%, 30.3%, and 35.1% and 32.5% respectively by adding 1% amphoteric starch LS-L2 -1 (0.034), LS-L2-2 (0.040), LS-L2-3 (0.047) and LS-L2-4 (0.052). But the strength of handsheets if affected a little. By adding 2% Al2 (SO4)3 and 1.5% LS-L2-3 at pH 7.5, filler retention can be improved from 38% to 80%, and breaking length of sheet only decreases 3.2%. As dry strengthening aids, amphoteric starches were used in eucalyptus APMP. Amphoteric starches are used in eucalyptus APMP. The amphoteric starch LS-L2-2 is better dry strength aid. Adding 1% LS-L2-2 can improve breaking length 24.5%, burst index 42.9%, tear index 38.8%, folding endurance and density of the handsheets.

Theoretical Terrains and Design Strategies of Landscape Urbanism (Landscape Urbanism의 이론적 지형과 설계 전략)

  • 배정한
    • Journal of the Korean Institute of Landscape Architecture
    • /
    • v.32 no.1
    • /
    • pp.69-79
    • /
    • 2004
  • This Paper examines theoretical terrains and design strategies of landscape urbanism which is an emerging hybrid field at the intersection of architecture, landscape architecture, and urbanism. Landscape urbanism offers alternative approaches for theory, education, and practice in contemporary landscape architecture. It views the emergent urban complex sites-post-industrial sites, landfill, brownfield, urban void, etc., not as a weakness, but as a strength. Landscape urbanism poses an understanding of landscape as an element of urban infrastructure. In this sense, the landscape is seen in the context of contemporary urban development and public works. As a complex amalgam, landscape urbanism is more than a design style it is an ethos, an attitude, a way of thinking and acting. We can chart the main characteristics of landscape urbanism such as horizontality and surface, infrastructure, process, technique, and ecology. Multilayered examples of landscape urbanism can be seen in several experimental practices such as worts of Rem Koolhaas, MVRDV, Adriaan Geuze/West 8, James Comer, etc. It is possible to summarize the productive strategies for landscape urbanism as follows : thickening, folding, new materials, nonprogrammed use, impermanence, and movement.

Effect of Mechanical Impact Treatment on Fiber Morphology and Handsheet Properties

  • Yung B. Seo;Kim, Dukki;Lee, Jong-Hoon;Yang Jeon
    • Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
    • /
    • 2001.11a
    • /
    • pp.183-199
    • /
    • 2001
  • Alternative way of shaping fibers suitable for papermaking was introduced. Impact refining, which was done simply by hitting wet fibers with a metal weight vertically, was intended to keep the fibers from shortening and to cause mostly internal fibrillation. Virgin chemical pulp, its recycled one and OCC were used in the experiment. It was noticed from the experiment that impact refining on virgin chemical pulp kept the fiber length and Increased bonding properties greatly, However, in the recycled fibers from the chemical pulp, fiber length and bonding properties were decreased. In OCC, which seems to contain fractions of semi-chemical pulp and mechanical pulp (GP), and which is recycled pulp from corrugated boxes, fiber length and bonding properties were decreased disastrously. We believe recycled cellulosic fibers (recycled chemical pulp and OCC in this case), which went through hornification, were less resistant to the mechanical impact than virgin chemical pulp. For virgin chemical pulp, impact refining allowed no significant fiber length shortening, high WRV, and high mechanical strength.

  • PDF

New Korean Traditional Papermaking from Paper Mulberry(III)-Properties of the Hanjis Mixed with Bast Part and Whole Stalk Pulps- (닥나무를 이용한 새로운 한지의 제조(제3보)-인피부 및 전간부 펄프 혼합초지 한지의 특성-)

  • 최태호;조남석
    • Journal of Korea Technical Association of The Pulp and Paper Industry
    • /
    • v.30 no.2
    • /
    • pp.85-95
    • /
    • 1998
  • Traditionally, Hanji had been made only with the bast fiber of paper mulberry (Broussonetia kazinoki). Nowadays, Hanji has been made mainly in the mixed forms of paper mulberry bast fiber and waste paper, and consequently it has raised many problems using them. This study was carried out to investigate the characteristics of Hanji mixed with paper mulberry bast part and whole stalk pulps. Hanjis made from the solfomethylated pulp were shown higher brightness and sheet strengths than those from alkali and alkali-hydrogen peroxide pulps. The brightness of solfomethylated pulp was found to be high enough not to need additional bleaching. The sheet formations were improved as the increase of whole stalk pulp contents, while the sheet strengths were decreased. In the physical properties of the Hanji mixed with bast part and whole stalk pulps, the handsheet strengths were decreased as the increase of the whole stalk pulp contents. The tensile strength and folding endurance of the Hanji containing 40∼60% of whole stalk pulps were higher as compared to the others.

  • PDF

An Investigation on the Forging Process of an Irregular Shape Product (비대칭 형상제품의 단조공정에 관한 연구)

  • 정경빈;김현수;최영순;김용조
    • Proceedings of the Korean Society of Precision Engineering Conference
    • /
    • 2004.10a
    • /
    • pp.1101-1104
    • /
    • 2004
  • A brake spider in an irregular shape, which is used as a part in the braking system of a vehicle like a big truck and a trailer, is subjected to a large torque and hence requires both strength and endurance over the brake heat. Manufacture of this product in practice is generally composed of hot forging processes and machining. At the present study, two or more processes were considered for the hot forging. With an initial circular billet, blocker and finisher processes were analyzed using the rigid-plastic finite element method and also in addition to the preforming process. Proper forging processes to manufacture an irregular product without forging defects, which are preforming, blocker and finisher, were discussed and commented upon.

  • PDF

Starch Treatment for the Improvement of Physical Properties of Hanji(I) - Effect of Starch Types - (한지의 강도적 성질 개선을 위한 전분류 처리(제1보) - 전분류별 처리효과 -)

  • 백옥례;윤승락
    • Journal of Korea Technical Association of The Pulp and Paper Industry
    • /
    • v.35 no.3
    • /
    • pp.59-65
    • /
    • 2003
  • This research was conducted to investigate the physical properties of Hanji made using maize, konyaku, and wheat powders at various concentrations. Regardless of the starch types, the most effective concentration to increase the physical properties of Hanji was 2 percent. They were significantly improved even at the treatment conditions of 0.1 percent. All the Hanji treated showed the increase of the breaking length, bust index, and tear index and the decrease of the folding number. The strength properties of the Hanji treated were markedly improved at 8 to 10 percent weight increase. The highest mechanical properties were found in the Hanji treated with konyaku powder.

A Study on the Defect of T type Forging Products (T형 다조부품의 결함에 관한 연구)

  • 손경호;김영호;서윤수
    • Proceedings of the Korean Society of Precision Engineering Conference
    • /
    • 1997.04a
    • /
    • pp.952-956
    • /
    • 1997
  • This paper describes the method that can expand the forming limit of T type forging products used in aircraft and automotive forged products. The forming limitis determined by the ratio of web thickness to rib width in T type and the reduction in height of workpiece and especially depends on the ratio of web thickness to rib width. For this method, the geometric condition that consists of triangle type was introduced and FEM simulations and model exoeriments were carried out and compared with each other. The objective of this paper is to give the method not only that sink mark and folding phenomenon are eliminated but also that the forming limit and the structural strength of rib and web is increased.

  • PDF

The Requirements for Permanent Paper and Evaluation of Permanence of Domestic Printing and Writing Papers (보존용지의 요구 특성 및 국내산 인쇄용지의 보존성 평가)

  • Youn, Hye-Jung;Cho, Hwi
    • Journal of Korea Technical Association of The Pulp and Paper Industry
    • /
    • v.40 no.2
    • /
    • pp.73-79
    • /
    • 2008
  • The permanence is of great importance to library and archival paper. According to the established standardizations including ISO and ANSI, the permanence can be specified with tear strength, pH, alkali reserve and kappa number. In this study, we evaluated the permanence and durability of domestic coated and copy paper grades. Two types of coated paper grades and all kinds of copy papers which were tested in this study were satisfied with the criterion of permanence specification. However, all of the tested paper grades didn't meet the requirements of durability because of their low folding endurance.

Investigation on the Lab Scale Corrugator's Optimum Operating Conditions for Making Microflute Corrugated Paperboards (마이크로플루트 골판지생산을 위한 실험용 코루게이터의 최적 운전조건 탐색)

  • Cho, Yong-Min;Um, Gi-Jeung
    • Journal of Korea Technical Association of The Pulp and Paper Industry
    • /
    • v.39 no.2 s.120
    • /
    • pp.54-59
    • /
    • 2007
  • Cereal, computer software, wine, small appliances, and fast foods are examples of products that have switched from folding carton to microflute corrugated paperboard. Microflute corrugated paperboards have their unique wonderful packaging characteristics that are driving forces for people to use more and more. Good strength property, excellent shock absorbing ability, and beautiful outer appearance of microflute corrugated paperboards go hand and hand with their environmental advantages. It is known that physical properties of microflute corrugated paperboards depend on not only properties of base paper but corrugator operating conditions. This study was carried out to investigate on the corrugator's optimum operating conditions for making micro flute corrugated paperboards. Lab-scaled micro flute corrugator was installed and run with systematic changes of operation conditions to investigate the effects of operation conditions on physical properties of micro flute corrugated paperboards.

Effect of Loquat Leaf Powder Addition on Quality of Fish Paste (어묵 제조 시 비파잎 첨가가 품질에 미치는 영향)

  • Park, In-Duck
    • Journal of the East Asian Society of Dietary Life
    • /
    • v.24 no.6
    • /
    • pp.837-844
    • /
    • 2014
  • This study was conducted to promote the utilization of fish paste containing loquat leaf powder (LLP). The tested concentrations of LLP were 0, 3, 5 and 7%. The pH of samples ranged from 6.75 to 6.89, and moisture content ranged from 75.23 to 76.95%. The L values of samples decreased as the concentrations of LLP decreased, and a and b values increased. In the folding test, all test samples with AA showed good flexibility. In the texture meter test, hardness, strength, springiness, gumminess and chewiness increased according to increasing concentrations of LLP. In the sensory evaluation, fish paste prepared with 5% LLP was preferred over other fish pastes. These results suggest that LLP can be applied to fish paste for the purpose of high quality and functionality.