• 펄프종이기술
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• 제41권5호
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• pp.1-7
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• 2009

Oxidized acetate starch was synthesized from corn oxidized starch and vinyl acetate. The sizing concentration and degree of substitution of modified starch on surface strength, smoothness and water resistance of the paper have been studied. The results showed that the surface strength, smoothness and other properties of paper sized by oxidized acetate starch is better than that of oxidized starch. When the degree of substitution of modified starch is from 0.04 to 0.14, the properties of paper sized by oxidized acetate starch have been improved more effectively.

• Computers and Concrete
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• 제25권1호
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• pp.59-65
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• 2020

The premise for the study reflected in this article is the need to dispose of industrial waste, which is increasingly being used in the construction materials industry. Also, dynamically developing building industry demands attention of scientists and a direction of their works on improvement of the technology of carrying out construction works. Thus, the article is devoted to studying the influence of various chemical additives and fine fillers (industrial wastes) available in Kazakhstan on self-compacting concrete (SCC) mixtures and its rheological, physical, and technical properties. According to the studies, revealed the most efficient type of fine-dispersed filler and the most optimal type of chemical additive to enable obtaining a high-quality SCC mixture based on local raw materials. As a result, the use of microsilica in comparison with other industrial wastes resulted in a conglomerate with high compressive strength of SCC at early terms of curing. In terms of economic efficiency and quality improvement, the results of study are of practical value for the manufacturers of ready-mixed concrete operating in Kazakhstan.

• 펄프종이기술
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• 제33권4호
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• pp.49-54
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• 2001

This study was carried out to acquire basic data for the bleaching of bamboo chemical pulp. Bamboo chemical pulps (alkaline sulfite (AS)-anthraquinone (AQ) pulp, Kraft pulp) were bleached with two kinds of multistage bleaching methods (CEDED, PDED) using the various kinds of bleaching agents. And, physical properties of bleached pulps were investigated. The conclusions obtained from the results were as follows; The yield of AS-AQ pulp bleached with four-stages bleaching method using the hydrogen peroxide and chlorine dioxide as a bleaching agents was higher than the other bleached pulps. The brightness of kraft pulp bleached with five-stages bleaching method using the chlorine and chlorine dioxide as a bleaching agents was higher than the other bleached pulps. The physical properties of kraft pulp bleached with four-stages bleaching method using the hydrogen peroxide and chlorine dioxide as a bleaching agents was higher than the other bleached pulps.

• 한국펄프종이공학회:학술대회논문집
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• 한국펄프종이공학회 2008년도 추계학술발표논문집
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• pp.1-10
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• 2008

• 한국펄프종이공학회:학술대회논문집
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• 한국펄프종이공학회 2011년도 추계학술발표회 논문집
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• pp.43-47
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• 2011

In woody waste separated from municipal solid waste, medium density fiberboard was major contributors with particleboard, paper, plywood and log, with different composition based on collected period. In chemical compositional analysis of woody waste, it was similar to softwood based on carbohydrate composition analysis. Based on the carbohydrate composition, saccharified solution from MWW could be good resource for biorefinery.

• 대한화학회지
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• 제53권5호
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• pp.565-569
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• 2009

폴리비닐피롤리돈(PVP)과 은 양이온과의 상호작용을 상온 및 상압 조건에서 연구하였다. PVP 와 PVP/Ag 복합체는 투과전자현미경(TEM), 자외선/가시선 흡수분광법, 라만분광법, 산소/이산화탄소 분석기를 통하여 관측하였다. 은 양이온은 PVP분자의 카르보닐기 산소원자에 있는 비공유전자쌍과 상호작용하여 안정한 PVP/Ag 복합체를 형성하는 것을 확인할 수 있었다.

• 펄프종이기술
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• 제39권1호
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• pp.8-15
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• 2007

In an effort to develop control strategies for the wet-end of paper machines, dynamic models for retention and formation processes have been developed. The retention process, including headbox total and filler consistencies, white water total and filler consistencies, the basis weight and the ash content of paper, can be modeled from first-principles (mass balances). To include the effect of wet-end chemistry variables, first-pass retention was included as a parameter dependent on operating conditions. In addition, dynamics of formation was simulated by developing an empirical model of formation and coupling with the dynamic models for the retention process. A series of experiments were performed using a pilot paper machine. The experimental results and the model predictions showed relatively good agreement.

• 한국산업융합학회 논문집
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• 제25권6_1호
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• pp.953-959
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• 2022

In this paper, the design result of robotic tools and the development of robot control system for chemical coupler assembly are presented. This research aims to eliminate the risk of chemicals exposed to human operators by developing the robotic tools and robot automation system for chemical tank lorry unloading that were done manually. Due to tight tolerance between couplers, even small pose error may result in very large internal force. In order to resolve the problem, the 6-axis compliance device is employed, which can provide not only enough compliance between couplers but also F/T sensing. The 6-axis compliance device having large force and moment capacity is designed. A simple linear gripper with rack-and-pinion is designed to grasp two sizes of couplers. The proposed robot automation system consists of 6-DOF collaborative robot with offset wrist, 6-axis compliance device with F/T sensing, linear gripper, and two robot visions.

• Bulletin of the Korean Chemical Society
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• 제31권5호
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• pp.1187-1191
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• 2010

$^1H-^{15}N$ heteronuclear dipolar coupling solid-state NMR experiments on lipid bilayer or bicelle samples are very useful for the structural studies of membrane proteins. However, to study these biological samples using solid-state NMR, a specific probe with high efficiency and high capability is required. In this paper, we describe the optimized design, construction, and efficiency of a 400 MHz wide-bore $^1H-^{15}N$ solid-state NMR probe with 5-mm solenoidal rf coil for high power, multi-pulse sequence experiments, such as 2D PISEMA or 2D SAMMY.

• Bulletin of the Korean Chemical Society
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• 제33권2호
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• pp.535-540
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• 2012

A series of benzamide-based histone deacetylases (HDACs) inhibitors possessing N-(aminopyridine) residue as the zinc binding site of HDAC were synthesized and evaluated. Among these derivatives, compounds with N-(2-amino-4-pyridine) benzamide moiety have been found as the most potent ones. Moreover, introduction of appropriate substituents on the terminal aryl group acting as the surface-recognition domain could significantly improve the antiproliferative activity. In particular, the compound 4k possessed favorable pharmacokinetic characteristics and exhibited potent antitumor activity on xenograft model in mice at well tolerated doses, thus suggesting a good therapeutic index.