• Title/Summary/Keyword: analytical methods

Search Result 3,062, Processing Time 0.035 seconds

Analytical Methods for Cationic Surfactants Sorbed by Fabrics (직물에 흡착된 양이온계면활성제 정량방법에 관한 연구)

  • 박선경;정혜원
    • Journal of the Korean Society of Clothing and Textiles
    • /
    • v.24 no.3
    • /
    • pp.422-428
    • /
    • 2000
  • At present, analytical methods available for determining the amount of cationic surfactants(DSDMAC) on the fabrics are spectrophotometric method based on formation and extraction of the colored ion pair with anionic dye, radiochemical analysis and HPLC analysis. This study presents new analytical methods based on the formation of cationic surfactant(DSDMAC)-disulfine blue complex on the cotton fabric. Test methods for determining the amount of DSDMAC-disulfine blue complex on the cotton fabrics are measuring the reflectance of the colored fabric and the absorbance of the methanol solution of DSDMAC-disulfine blue complex extracted from dyed cotton fabric. Linear relationships between the K/S value of the fabric treated with DSDMAC followed by disulfine blue and the amount of DSDMAC sorbed by cotton fabric were obtained. Thus, the amount of DSDMAC sorbed by cotton fabric can be determined by K/S value of the fabric. DSDMAC-disulfine blue complex on the cotton fabric was extracted with methanol. The amount of DSDMAC sorbed by cotton fabric was estimated by measuring the absorbance of the methanol solution extracted from dyed cotton fabric.

  • PDF

A study of analytical method for volatile fatty acids (VFA) by cryogenic trapping-thermal desorption (CT-TD) technique (저온농축열탈착 시스템을 연계한 유기지방산의 분석법 평가 및 검토)

  • Ahn, Ji-Won;Kim, Ki-Hyun;Im, Moon-Soon;Ju, Do-Weon
    • Analytical Science and Technology
    • /
    • v.24 no.3
    • /
    • pp.200-211
    • /
    • 2011
  • In this study, 13 compounds including four volatile fatty acids (VFA) and nine volatile organic compounds (VOC) were analyzed by cryogenic trapping-thermal desorption technique. In order to evaluate the analytical method for VFA, calibration experiments were performed using five different sorbent materials. When the calibration results are compared between different sorbents, sampling tube filled with Carbopack X showed the highest response factor (RF) for both VFA and VOC. To validate this new analytical method for VFA using cryogenic trapping-thermal desorption technique, this method was compared with alkali absorption method recommended by the odor prevention law of the Korea Ministry of Environment (KMOE). For this purpose, unknown samples were analyzed by two different methods, i.e., cryogenic trapping-thermal desorption (TD) and alkali absorption with solid phase microextraction (SPME). When the results of two different methods were compared, ratios of concentrations determined by the two analytical methods (TD/SPME) was found as 0.46 (valeric acid) ~ 0.71 (isovaleric acid). Therefore, additional study is required to properly establish and find stable analytical conditions for VFA analysis. Furthermore, comparison between two different methods should be made with more reliable calibration approaches.

Analytical Techniques For Use With Frame Photography (일반(一般) 카메라에 의한 위치결정의 해석적(解析的) 기법(技法)에 관한 연구)

  • Yang, In-Tae
    • Journal of Industrial Technology
    • /
    • v.5
    • /
    • pp.3-7
    • /
    • 1985
  • Analytical techniques for use with reconnaissance frame photographs are outlined. The first approach is a point-by-point space resection in which the dynamic properties of the camera are taken into account. In the second approach appropriate parameters are added to correct for image distoritions, caused by the focal plane shutter, during the space resection phase. Test results showed that the analytical techniques developed will significantly improve the planimetric and height accuracy obtained by conventional methods.

  • PDF

An analytical Study on the premature Failure Behavior of RC Beams Strengthened by Steel Plates (강판으로 보강된 RC 보의 조기파괴거동 해석)

  • 심종성;김규선
    • Proceedings of the Korea Concrete Institute Conference
    • /
    • 1998.10b
    • /
    • pp.821-826
    • /
    • 1998
  • The design methods for the steel plate strengthened RC structures are not well established yet because the structural behavior of plated RC beams is more complex than that of regular unplated ones. The main purpose of this paper is to present the premature failure mechanism of steel plate strengthened RC beams. The analytical models of interfacial stress and normal are also proposed in this paper. The comparisons between the analytical results using the proposed theory and experimental ones relatively satisfied.

  • PDF

Establishment of Normal Reference Data of Analysis in the Fresh and Cryopreserved Canine Spermatozoa

  • Park, Byung-Joon;Lee, Hyeon-Jeong;Lee, Sung-Lim;Rho, Gyu-Jin;Kim, Seung-Joon;Lee, Won-Jae
    • Journal of Embryo Transfer
    • /
    • v.33 no.2
    • /
    • pp.75-84
    • /
    • 2018
  • The cryopreservation has been extensively applied in many cells including spermatozoa (semen) during past several decades. Especially, the canine spermatozoa cryopreservation has contributed on generation of progeny of rare/genetically valuable dog breeds, genome resource banking and transportation of male germplasm at a distant place. However, severe and irreversible damages to the spermatozoa during cryopreservation procedures such as the thermal shock (cold shock), formation of intracellular ice crystals, osmotic shock, stress of cryoprotectants and generator of reactive oxygen species (ROS) have been addressed. According as a number of researches have been conducted to overcome these problems and to advance cryopreservation technique, several analytical methods have been employed to evaluate the quality of the fresh or cryopreserved canine spermatozoa in regards to the motility, morphology, integrity of membrane and DNA, mitochondrial activity, ROS generation, binding affinity to oocytes, in vitro fertilization potential and fertility potential by artificial insemination. Because the study designs with certain application of analytical methods are selective and varied depending on each experimental objective and laboratory condition, it is necessary to establish the normal reference data of the fresh or cryopreserved canine spermatozoa for each analytical method to monitor experimental procedure, to translate raw data and to discuss results. Here, we reviewed the recent articles to introduce various analytical methods for the canine spermatozoa as well as to establish the normal reference data for each analytical method in the fresh or cryopreserved canine spermatozoa, based on the results of the previous articles. We hope that this review contributes to the advancement of cryobiology in canine spermatozoa.

A Comparative Study on the Analytical Methods of Polycyclic Aromatic Hydrocarbons in the Atmosphere (대기 중 다환방향조탄화수소류의 분석 방법간 비교연구)

  • 박찬구;김민영;정동균;모세영
    • Journal of Korean Society for Atmospheric Environment
    • /
    • v.16 no.6
    • /
    • pp.595-606
    • /
    • 2000
  • In order to compare analytical conditions for measuring PAHs(polycyclic aromatic hydrocarbons) in ambient air, a series of experiment were conducted using three different types of extraction methods that include:(1) accelerated solvent extraction (ASE), (2) soxhlet, and (3) sonification methods. Efficiency and relevant analytixal parameters for each of these methods were examined on five different types of solvents that include:(1) 10% diethyl ether in n-hexane(v/v), (2) dichloromethane, (3)cyclohexane.(4) toluene, and (5) Benzene: ethanol (4:1). Comparison of extraction efficiency for various combinations between methods and solvents was made through an application of both internal and external standard calibration techniques. The extraction efficiency tests, when checked using both internal and external standards, allowed us to derive meaningful comparison among different techniques and among solvents.

  • PDF

The analysis of pesticide residue in leafy vegetables using the modified QuEChERS pre-treatment methods (QuEChERS 시료 처리법을 활용한 엽채류 중 잔류농약분석)

  • Kim, Yang-Hyeon;Hong, Su-Myeong;Son, Kyung-Ae;Lee, Ju-Young;Min, Zaw Win;Kwon, Hye-Young;Kim, Taek-Kyum;Kyung, Kee-Sung
    • The Korean Journal of Pesticide Science
    • /
    • v.16 no.2
    • /
    • pp.121-130
    • /
    • 2012
  • In analyzing pesticide residue, LLE (liquid liquid extraction) is generally applied as one of the existing methods, but needed quite a lot of organic solvents and analytical apparatuses for the sample pre-treatment. In addition to its long analysis time and complex analytical processes, it is required to develop a more rapid and efficient method at present. In order to establish an economic and simple pesticide residue analytical method, this study carried out a comparative experiment on the existing analytical method with a new sample pre-treatment method named QuEChERS (quick, easy, cheap, effective, rugged and safe), which extracts and refines pesticide components by directly adding solid powder into the sample. Both the two analytical methods showed favorable values of correlation coefficient ($R^2$ > 0.99) of calibration curves. In terms of the detection limit (identification limit), imidacloprid showed 0.02 mg/kg, while the rest of pesticides showed a level around 0.05 mg/kg. The results of this experiment revealed that the recovery of LLE was 92.8-100.9% and the RSD was below 2.5%. On the other hand, the recovery of QuEChERS was 92.2-101.6% and RSD was below 1.9%. As a result of comparing the amount of pesticide residue by the time between the two analytical methods by using Paired t-Test, there was no significant difference between the two analytical methods as the p-value ranged from 0.3148-0.9890. Considering the results of the two methods, the QuEChERS method had similar recovery, compared to the analytical method using the existing LLE, and the analytical time was shortened by about one fourth of that of the existing method. Moreover, since it excludes the use of harmful organic solvents like dichloromethane during the process of extraction, thus leading to protecting experimenters health and remarkably reducing the amount of disused solvents, it is judged as an echo-friendly and economic analytical method.

An analytical approach for nonlinear response of elastic cable under complex loads

  • Lu, L.Y.;Chan, S.L.;Lu, Z.H.
    • Structural Engineering and Mechanics
    • /
    • v.5 no.3
    • /
    • pp.329-338
    • /
    • 1997
  • In this paper a general analytical approach is proposed to analyse the nonlinear response of elastic cable under complex loads. The effect of temperature change on the cable is also considered. From the vertical equilibrium equations of cable, the general analytical formula of vertical displacement is derived. Based on the vertical displacement formula and on the compatibility condition of the cable, the dimensionless equation with respect to cable tension is established. By means of such analytical procedures, the exact solutions of various cable problems can be obtained quickly. The example given in this paper shows that the new procedure is efficient for practical analysis and can be easily implemented by a general computer program without the superposition problem which there has always been in traditional analytical methods.

Efficiency Optimal Design of a Brushless DC Motor Considering the Magnetization Direction of Permanent Magnet (영구자석의 착자방향을 고려한 브러시리스DC 전동기의 효율 최적화 설계)

  • Song, Jeong-Hyun;Kim, Byung-Taek
    • Journal of Institute of Control, Robotics and Systems
    • /
    • v.17 no.3
    • /
    • pp.241-247
    • /
    • 2011
  • This paper is intended to improve efficiency of two-phase BLDC motor using analytical and statistical methods, and then the stability of the starting for the designed model is investigated. The characteristics of the motor according to magnetization directions of permanent magnet are analyzed through the analytical method, and design variables that affect the efficiency are selected. Preliminary optimal design is performed using the analytical method with the design variable. The RSM (Response Surface Method) based on the FEA (Finite Element Analysis) is applied to complement errors of the analytical method. As a result, the optimal design is determined. Finally, the stability of the starting for the optimal designed model is evaluated by analyzing cogging torque, and it is verified through the FEA.