• Title/Summary/Keyword: rheological properties

Search Result 1,377, Processing Time 0.031 seconds

Effect on Milking Performance of Vitamin-Trace Element Supplements to Early Lactation Italian Brown Cows Grazing Ryegrass (Lolium multiflorum) Pasture

  • Tufarelli, Vincenzo;Khan, R.U.;Laudadio, V.
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.24 no.9
    • /
    • pp.1227-1232
    • /
    • 2011
  • The objective of this study was to examine the effects of concentrates containing different levels of a vitamin-trace elements premix on milk yield and composition of dairy cows. The trial, which lasted 14 weeks, was conducted from January to March and used 45 multiparous Brown cows in the early phase of lactation. Cows (n = 15 per treatment) were randomly allocated to three dietary treatments: the first group (control, C-0) was fed pelleted concentrate containing background vitamins and trace elements that supplied 1.0 times cows' daily requirements; the second group were fed the same concentrate, but containing 2.5 g/kg of vitamin and trace mineral premix per kg of concentrate (C-2.5); the third group were fed the same concentrate, but containing 5 g/kg of vitamin and trace mineral premix per kg of concentrate (C-5). The daily ration included ad libitum chopped oat hay, and the cows also had 8 h/d grazing on a ryegrass (Lolium multiflorum) pasture. During the performance trial, cow milk yield was daily recorded and individual milk samples were analysed for milk composition and to determine milk renneting properties. Cows fed the intermediate premix level (C-2.5) in diet showed the highest fat-corrected milk production (p<0.05) compared to other groups. None of the milk quality parameters studied were influenced by dietary treatment, except for milk rheological parameters (rennet clotting time and curd firmness) that were positively improved in cows fed the C-2.5 diet (p<0.05). The findings from this study show that intermediate level of vitamin-trace elements premix in concentrate can be advantageously used in grazing dairy cows without negative effects on yield and quality of milk produced.

Physical Property and Morphology Observation of HepG2 Cells by Various Concentration of Paraquat (파라쿼트 농도에 따른 HepG2 세포의 물리적 특성 변화와 실시간 모폴로지 관찰)

  • Lee, Dong-Yun;Kang, Hyen-Wook;Muramatsu, Hiroshi;Kwon, Young-Soo
    • Proceedings of the KIEE Conference
    • /
    • 2009.07a
    • /
    • pp.1232_1233
    • /
    • 2009
  • Paraquat is well-known to cause hepatotoxic responses in human and other mammal species. In solution, it forms free radicals and charge-transfer complex of which formation plays an important role in determination of its biological activity in the presence of various anions. The HepG2 cells were cultured onto a quartz crystal sensor which is possible to detect the density and a viscosity changes using the resonance frequency (F) and the resonance resistance (R). The plot of F-R diagram is able to explain the rheological change of cells onto the surface of the quartz crystal sensor. In this paper, we investigated the physical properties of the HepG2 cells cultured onto a ITO electrode of the quartz crystal sensor according to the paraquat injection at various concentrations (100 mM, 10 mM, 1 mM). We also observed the morphological changes with a micro CCD camera, simultaneously. The HepG2 cells were cultured onto the ITO electrode surface of the quartz crystal modified a collagen film in $CO_2$ incubator. After the paraquat injection, we observed the changes of the morphologies by the micro CCD camera depending on time and analyzed the physical changes of cells on the electrode surface of quartz crystal using F-R diagram. From all results, we proved the effect of paraquat at various concentrations which is led to an apoptosis such as weakening and death of the cells by oxidation and reduction reaction that were produced the superoxide anions and other free radicals.

  • PDF

Production and Rheological Properties of Bioflocculant Produced by Bacillus sp. DP-152

  • SUH, HYUN-HYO;SEONG-HOON MOON;HEE-SIK KIM;HYOUNG-KAB KIM;GEE-ILL JUN;HYUN-GEOUN PARK;DAE-OOK KANG;HEE-MOCK OH;BYUNG-DAE YOON
    • Journal of Microbiology and Biotechnology
    • /
    • v.8 no.6
    • /
    • pp.618-624
    • /
    • 1998
  • The culture conditions for Bacillus sp. DP-152 in the flask were investigated for the production of polysaccharide locculant, DP-152. The optimum pH and temperature for the locculant production were 8.0 and $30^{\circ}C$, respectively. The avorable substrates for flocculant production were soluble tarch and ammonium nitrate. The medium composition was optimized as follows: 30 g soluble starch, 0.75 g $NH_4NO_3,\; 2.0g\; K_2\;HPO_4,\; 0.1\; g KH_2PO_4,\; 0.2g\; MgSO_4.\; 7H_2O,\; and\; 0.2g\; MnSO_4~5H_2O$ in 11 of distilled water. Under this optimized condition, flocculating activity has been improved 4-fold compared with that of the basal medium. In the culture flask, the highest flocculating activity was obtained after 70 h of cultivation and the amount of bioflocculant DP-152 yielded was 12.4 g/$\ell$. The solution of bioflocculant DP-152 showed non-Newtonian characteristics. Bioflocculant DP-152 exhibited apparently higher viscosity at all concentrations compared to that of zooglan (from Zoogloea ramigera), and it was stable over a wide range of temperatures and pHs.

  • PDF

Rheological Properties of a Novel High Viscosity Polysaccharide, A49-Pol, Produced by Bacillus polymyxa

  • Kim, Seon-Won;Ahn, Seung-Gu;Seo, Weon-Taek;Kwon, Gi-Seok;Park, Young-Hoon
    • Journal of Microbiology and Biotechnology
    • /
    • v.8 no.2
    • /
    • pp.178-181
    • /
    • 1998
  • An exopolysaccharide, designated as A49-Pol, was produced from Bacillus polymyxa KCTC 8648P in nitrogen sufficient conditions. The viscosity of the culture broth increased up to $2\times10^4$cP in 38 hours of culture and then decreased to $1.5\times10^4$CP at 48 hours. The $1.0\%$ (w/v) solution of purified A49-Pol represented pseudoplasticity with a viscosity of $2.7\times10^4$cP which was two times higher than xanthan at the same concentration. The viscosity of the A49-Pol solution was also greatly affected by its concentration in comparison with the xanthan solution. The viscosity of $1.0\%$ A49-Pol solution was 930-fold higher than its $0.2\%$ solution, whereas the corresponding viscosities of xanthan solution experienced only l7-fold difference. The viscosity was observed to be maximum at pH 7.0 in both A49-Pol and xanthan solutions, and gradually decreased as the pHs of the polysaccharide solutions went to acidic or alkaline regions. The viscosity of A49-Pol solution was very sensitive to temperature compared to xanthan and decreased with increasing temperature. The viscosity of $0.6\%$ solution of A49-Pol was 8,100 cP at $10^{\circ}C$ and 55 cP at $50^{\circ}C$. The viscosity was also affected by the presence of surfactants such as Span 20 and Triton X-l00 ; with $0.5\%$ Triton X-l00 (v/v), the viscosity of A49-Pol solution increased by $50\%$.

  • PDF

Quality Characteristics of White Pan Bread with Olive Oil (올리브유를 첨가한 식빵의 품질특성에 관한 연구)

  • Lee, Sun-Heui;Yun, Mi-Suk;Lee, Jung-Hoon;Min, Sang-Gi;Lee, Si-Kyung
    • Applied Biological Chemistry
    • /
    • v.48 no.3
    • /
    • pp.217-221
    • /
    • 2005
  • This study was carried out to investigate the quality characteristics of white pan breads made with shortening and with olive oil by measuring moisture content, baking loss, specific loaf volume and rheological properties. Moisture contents of the white pan breads made with 4% and 6% olive oil were about 39.8% while those made with 4% shortening were $38.68{\pm}0.41%$. There were no signigicant differences in baking loss between the white pan bread made with 4% shortening, and those made with 4% and 6% olive oil. The specific loaf volume of the white pan bread made with 4% olive oil was 4.08 ml/g and the result showed lower value than that of the white pan bread made with 4% shortening. In terms of hardness and springness, there were no significant differences according to the sort and the amount of lipids, however white pan bread made without oil was the greatest in hardness.

Bending of a rectangular plate resting on a fractionalized Zener foundation

  • Zhang, Cheng-Cheng;Zhu, Hong-Hu;Shi, Bin;Mei, Guo-Xiong
    • Structural Engineering and Mechanics
    • /
    • v.52 no.6
    • /
    • pp.1069-1084
    • /
    • 2014
  • The long-term performance of plates resting on viscoelastic foundations is a major concern in the analysis of soil-structure interaction. As a powerful mathematical tool, fractional calculus may address these plate-on-foundation problems. In this paper, a fractionalized Zener model is proposed to study the time-dependent behavior of a uniformly loaded rectangular thin foundation plate. By use of the viscoelastic-elastic correspondence principle and the Laplace transforms, the analytical solutions were obtained in terms of the Mittag-Leffler function. Through the analysis of a numerical example, the calculated plate deflection, bending moment and foundation reaction were compared to those from ideal elastic and standard viscoelastic models. It is found that the upper and lower bound solutions of the plate response estimated by the proposed model can be determined using the elastic model. Based on a parametric study, the impacts of model parameters on the long-term performance of a foundation plate were systematically investigated. The results show that the two spring stiffnesses govern the upper and lower bound solutions of the plate response. By varying the values of the fractional differential order and the coefficient of viscosity, the time-dependent behavior of a foundation plate can be accurately captured. The fractional differential order seems to be dependent on the mechanical properties of the ground soil. A sandy foundation will have a small fractional differential order while in order to simulate the creeping of clay foundation, a larger fractional differential order value is needed. The fractionalized Zener model is capable of accounting for the primary and secondary consolidation processes of the foundation soil and can be used to predict the plate performance over many decades of time.

Preparation and Evaluation of Titrated Extract of Centella Asiatica Niosome/W/O System Cream for Site Specific Targeting (니오좀을 이용한 병풀 추출물 외용제의 제조 및 평가)

  • Kim, Dong-Woo;Cho, Mi-Hyun;Park, Sun-Young;Lee, Jong-Hwa;Lee, Gye-Won;Park, Mork-Soon;Park, Jin-Kyu;Jee, Ung-Kil
    • Journal of Pharmaceutical Investigation
    • /
    • v.32 no.4
    • /
    • pp.291-297
    • /
    • 2002
  • For preventing and curing the stretching mark, TECA Niosome/W/O system creams were formulated using Titrated Extract of Centella Asiatica (TECA) which is well known for its excellent wound healing effect. The lipid-water partition coefficients and the stabilities of TECA were evaluated and TECA Niosome/W/O system (TECA N/W/O) creams were prepared with different concentrations of cetyl alcohol and ceramide. TECA N/W/O cream was evaluated with respect to their rheological properties, permeation through excised skin of hairless mouse and in vitro and in vivo accumulation in the skin of hairless mouse. In addition, dermal thicknesses of hairless mouse skins were determined following the in vivo application of TECA N/W/O cream and control cream. TECA N/W/O creams showed pseudoplastic flow and hysteresis loop. The permeation of TECA from formulations through excised skin of hairless mouse did not observed. Amount of accumulated drug in the excised skin of hairless mouse was deσeased with an increase in the concentration of cetyl alcohol and showed no relationship with concentration of ceramide. Amount of accumulated drug in formulation A-3 was higher than in niosome suspension and other formulations. In in vivo experiment, amount of accumulated drug in formulation A-2 and A-3 was much higher than that of niosome suspension. Being treated with the N/W/O cream for 8 weeks, the dermal thickness of hairless mouse skin was increased 3.2 times than that of 16 weeks-control group.

Production and Rheological Properties of the Polysaccharide from Bacillus sp. A29 (Bacillus sp. A29에 의한 다당류의 생산과 물성)

  • Ahn, Sung-Ku;Suh, Hyun-Hyo;Lee, Chang-Ho;Oh, Hee-Mock;Kwon, Gi-Seok;Yi, Dong-Heui;Yoon, Byung-Dae
    • Microbiology and Biotechnology Letters
    • /
    • v.22 no.2
    • /
    • pp.175-181
    • /
    • 1994
  • A bacterial strain producing highly viscous polysaccharide(A29 POL) was isolated from soil and identified sa Bacillus sp. A29. The cultural conditions of the Bacillus sp. A29 for the polysaccharide prouction were dextrin 12%, soytone 0.2%, SnCl$_{2}$ $\cdot $2H$_{2}$O 0.02%, Na$_{2}$HPO$_{4}$ $\CDOT $12H$_{2}$O 0.36%, L-alanine 0.01%, initial pH6.8, and 30$\circ $C at pH 3 FOR 4 days. Final viscosity of the culture broth was 65, 000 cp and then the amount of produced polysaccharide was 8.3 g/l. A29 POL was composed of glucose and xylose. A29 POL showed high viscosity at low concentration(0.1%) and in the presence of the salts such as NaCl or CaCl$_{2}$. A29 POL showed high viscosity acid condition and at alkali condition and high pseudoplasticity in the presence of a NaCl or CaCl$_{2}$. It was shown that the viscosity at high temperature(80$\circ $C) was decreased but it was recovered at low temperature (20$\circ $C. A29 POL was able to from film and gel in the presence of MgSO$_{4}$ $\CDOT $7H$_{2}$O, Na$_{2}$CO$_{3}$ \CDOT $H$_{2}$O, MnSO$_{4}$ $\CDOT $ 7H$_{2}$O. A29 POL had anionic charge.

  • PDF

Development of Novel Cosmetic Formulations using Foams (기포를 이용한 차별화된 화장품 제형 개발)

  • Cho, Wan-Goo
    • Journal of the Society of Cosmetic Scientists of Korea
    • /
    • v.38 no.1
    • /
    • pp.1-13
    • /
    • 2012
  • In this review, the use of air bubbles in the pharmaceutical and cosmetic formulations was discussed. The foam bubbles show different characteristics depending on the foaming agents and foam generating devices. The foam bubbles are generated in the form of dispersion of gas bubbles in a solvent. The assessment of stability and rheological properties of bubbles are the starting point for the formulation to be used. Pharmaceutical and cosmetic uses of bubbles are substantially growing, and the foam formulations of drugs can be used for rectal, vaginal, and dermal symptoms. The foam formulation is used in hair mousse, makeup foundation, and sunscreen cosmetics in basic cosmetics. Recently, a lot of studies and patents have been filed in stabilization of active ingredients and delivery of the active ingredient in terms of foam formulations. In the future, foam formulations are expected to be used as novel cosmeceutical formulations.

Flowability and Strength of Cement Composites with Different Dosages of Multi-Walled CNTs (다중벽 탄소나노튜브의 혼입량에 따른 시멘트 복합체의 유동성 및 강도 변화)

  • Ha, Sung-Jin;Kang, Su-Tae
    • Journal of the Korea Concrete Institute
    • /
    • v.28 no.1
    • /
    • pp.67-74
    • /
    • 2016
  • With several different dosages of multi-walled CNTs which was 0.1, 0.3, and 0.5% of the weight of binder, the fluidity in fresh CNT cement composites, as well as the strength and strength development with age of the hardened composites were investigated in this experimental study. The experimental results from flow test indicated that the increase in the dosage of CNTs badly impacted on the workability of fresh composites, and the results from rheological measurements presented the decrease in plastic viscosity and the increase in yield stress according to the amount of CNTs. In addition, the thixotrophy in the flow curve obtained from the rheology test was observed more noticeably in the composites with higher dosage of CNTs. With the experiments on the strength properties, the improvement of both compressive and tensile strengths with the increase of CNTs dosage could be obtained. Moreover, early strength development by adding CNTs was found when it was compared with plain cementious matrix without CNT.