• Title/Summary/Keyword: apparent first-order

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Speaking Subjects and Surplus Objects: Womanly Words in Dickens and Gaskell

  • Li, Fang
    • Journal of English Language & Literature
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    • v.57 no.3
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    • pp.457-472
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    • 2011
  • The word "subject," like its apparent antonym "agent" is ambiguous. By "speaking subject" I intend both meanings: the spoken about, and the speaker, and the spoken about, in more or less that order. The paper contrasts the way women are spoken about in the 19th Century debate over the role of women between John Ruskin and John Mill, and then in literary criticism of feminists nearer our own time, Kate Millet and Elizabeth Langland. I then move on to women as speaking subjects, first in the form of an imaginary speaking subject created by a male speaker, Charles Dickens channeling the confessional journal of Esther Summerson in Bleak House. The comparison with Elizabeth Gaskell, a genuine speaking subject, is highly instructive. I draw attention to symmetrical, in the sense of opposite, narrative strategies. Where Dickens begins in journalese, with a gritty, realistic opening that only gradually reveals a Cinderella in the ashes, Gaskell begins with a nursery rhyme, in an actual nursery, but goes on to reveal some rather sordid economic facts. Where Dickens creates a ventriloquist's doll, Gaskell succeeds in creating recognizable, if not always admirable, female voices. I conclude that just as the novel may be read as a real utterance in a real conversation, it is also possible to read the true emergence of women novelists in the 19th Century as nothing more and nothing less than the creation of the first truly womanly words about women: women as speaking subjects in both senses of the word.

Sorption Kinetics of Hydrophobic Organic Compounds in Wetland Soils (습지 토양에서 소수성 유기화합물질의 흡착 동력학)

  • Park, Je-Chul;Shin, Won-Sik
    • Korean Journal of Ecology and Environment
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    • v.36 no.3 s.104
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    • pp.295-303
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    • 2003
  • Sorption kinetics of hydrophobic organic compounds (chlorobenzene and phenanthrene) in natural wetland soils was investigated using laboratory batch adsorbers. One -site mass transfer model (OSMTM) and two compartment first-order kinetic model (TCFOKM) were used to analyze sorption kinetics. Analysis of OSMTM reveals that apparent sorption equilibria were obtained within 10 to 75 hours for chlorobenzene and 2 hours for phenanthrene, respectively. For chlorobenzene, the sorption equilibrium time for surface soil was longer than that of deeper soil presumably due to physico-chemical differences between the soils. For phenanthrene, however, no difference in sorption equilibrium time was observed between the soils. As expected from the number of model parameters involved, the three-parameter TCFOKM was better than the two-parameter OSMTM in describing sorption kinetics, The fraction of fast sorption ($f_1$) and the first-order sorption rate constants for fast ($k_1$)and slow ($k_2$) compartments were determined by fitting experimental data to the TCFOKM. The results of TCFOKM analysis indicate that the sorption rate constant in the fast compartment($k_1$) was much greater than that of slow fraction($k_2$) . The fraction of the fast sorption ($f_1$) and the sorption rate constant in the fast compartment($k_1$) were increasing in the order of increasing $k_{ow}$, phenanthrene > chlorobenzene. The first-order sorption rate constants in the fast ($k_1$) and slow ($k_2$) compartments were found to vary from $10^{-0.1}\;to\;-10^{1.0}$ and from $10^{-4}\;to-10^{-2}$, respectively.

Effects of NaOH and Humic Acid on the UV Photolysis of PCBs (PCBs의 광화학적 연구: NaOH 및 휴믹산 (humic acid, HA)에 의한 분해특성)

  • Shin, Hae Seung;Kim, Jae Hyoun
    • Journal of Environmental Health Sciences
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    • v.40 no.2
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    • pp.147-156
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    • 2014
  • Objectives: This study was carried out to examine whether the apparent photolysis with or without sensitizers [NaOH and humic acid (HA)] was prompted photodegradation of polychlorinated biphenyl (PCB) in aqueous solution. Methods: PCBs photodegradation occurred using fluorescence black lamps at ${\lambda}_{max}=300nm$. PCB congeners were exposed in 10 ppm HA or 0.05N NaOH solutions, to investigate the decreasing profile of PCB concentration with time. The PCBs were then analyzed by gas chromatography/mass spectrometry (GC-MS). Reductive degradation profile of PCB congeners in the presence of both sensitizers under oxygen-saturated protic conditions was described using the wind-rose diagrams. Results: Use of HA or NaOH decreased PCB concentration with time in the dark and on irradiation, indicating that photolysis underwent through reductive dechlorination through energy transfer and possibly with reactive oxygens. The dechlorination was marked by a chromatographic shift, observed in the GC-MS plots. Therefore it is logical to assume that increasing the dose of sensitizers would increase the photodegradation rates of PCBs. The half-lives of pentachloro-PCB (penta-3) in 0.05N NaOH and 10 ppm HA were estimated at about 47 hours and 39 hours, respectively, under the same experimental conditions of photolysis. It was found that the rate of photolysis of pentachloro-PCB in aqueous solution followed apparent first-order kinetics compared to other congeners. Conclusion: Photochemical degradation (using 328 nm UV light) of penta- and hexa-PCBs in HA or alkaline solution is a viable method for pretreatment method. The results are helpful for the further comprehension of the reaction mechanism for photolytic dechlorination of PCBs in aquatic system.

Saturable Disposition of Taurine in the Cerebrospinal Fluid of the Rat

  • Chung, Suk-Jae
    • Proceedings of the Korean Society of Applied Pharmacology
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    • 1996.11a
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    • pp.99-113
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    • 1996
  • Taurine, a ${\beta}$-amino acid, plays an important role as a neuromodulator and is necessary for the normal development of the brain. Since de novo synthesis of taurine in the brain is minimal and in vivo studies suggest that taurine does not cross the blood-brain barrier, the blood-cerebrospinal fluid (CSF) barrier is likely to play a role in taurine transport between the central nervous system and the systemic circulation. Therefore, we examined in vivo elimination of taurine from the CSF in the rat to characterize in vivo kinetics of elimination for taurine from the CSF is consistent with the in vitro study. Using a stereotaxic device, cannulaes were placed into the lateral ventricle and the cisterna magna of the rat. Radio-labelled taurine and inulin (a marker of CSF flow) were injected into the lateral ventricle, and the concentrations of the labelled compounds in the CSF were monitored for up to 3 hrs in the cisterna magna. The apparent clearance of taurine from CSF was greater than the estimated CSF flow (p<0.005), indicating that there is a clearance process in addition to the CSF flow. Taurine distribution into the choroid plexus was at least 10 fold higher than that found in other brain areas (e.g., cerebellum, olfactory bulb and cortex). When unlabelled taurine was co-administered with radio-labelled taurine, the apparent clearance of the labeled taurine was reduced (p<0.01), suggesting a saturable disposition of taurine from CSF. Distribution of taurine into the choroid plexus, cerebellum, olfactory bulb and cortex was similarly diminished, indicating that the saturable uptake of taurine into these tissues is responsible for the non-linear disposition. A pharmacokinetic model involving first order elimination and saturable distribution described these data adequately. The Michaelis-Menten rate constant estimated from in vivo elimination study is similar to that obtained in the in vitro uptake experiment Collectively, our results demonstrate that taurine is transported in the choroid plexus via a taurine is cleared from the CSF via a saturable process. This process may be functionally relevant to taurine homeostasis in the brain.

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Numerical simulation of electrokinetic dissipation caused by elastic waves in reservoir rocks

  • Zhang, Xiaoqian;Wang, Qifei;Li, Chengwu;Sun, Xiaoqi;Yan, Zheng;Nie, Yao
    • Geomechanics and Engineering
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    • v.19 no.1
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    • pp.11-20
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    • 2019
  • The use of electrokinetic dissipation method to study the fluid flow law in micro-pores is of great significance to reservoir rock microfluidics. In this paper, the micro-capillary theory was combined with the coupling model of the seepage field and the current field under the excitation of the harmonic signal, and the coupling theory of the electrokinetic effect under the first-order approximation condition was derived. The dissipation equation of electrokinetic dissipation and viscous resistance dissipation and its solution were established by using Green's function method. The physical and mathematical models for the electrokinetic dissipation of reservoir rocks were constructed. The microscopic mechanism of the electrokinetic dissipation of reservoir rock were theoretically clarified. The influencing factors of the electrokinetic dissipation frequency of the reservoir rock were analyzed quantitatively. The results show that the electrokinetic effect transforms the fluid flow profile in the pores of the reservoir from parabolic to wavy; under low-frequency conditions, the apparent viscosity coefficient is greater that one and is basically unchanged. The apparent viscosity coefficient gradually approaches 1 as the frequency increases further. The viscous resistance dissipation is two orders of magnitude higher than the electrokinetic effect dissipation. When the concentration of the electrolyte exceeds 0.1mol/L, the electrokinetic dissipation can be neglected, while for the electrolyte solution (<$10^{-2}M$) in low concentration, the electrokinetic dissipation is very significant and cannot be ignored.

Studies on the Stability of Multivitamin Solutions (종합비타민 액제의 안정성에 대한 연구)

  • Park, Hong-Koo
    • Applied Biological Chemistry
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    • v.43 no.1
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    • pp.39-45
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    • 2000
  • The stability of vitamin A, $B_1,\;B_2,\;B_6$, C in aqueous multivitamin solutions was carried out by means of estimation of reaction velocity and the results are described in this paper. The stability of vitamin A, $B_1$ and C due to thermal degradation method in aqueous multivitamin solutions was evaluated at 40, 50, 60 and $70^{\circ}C$ up to 40 days. The shelf-lives of vitamin A, B₁ and C in this preparation, calculated using the Arrhenius equation, were 1493, 449 and 639 days at $25^{\circ}C$ respectively. Examination was made on the effect of initial concentration of vitamin $B_2$$(C_0)$ on light fading of vitamin $B_2$ in aqueous multivitamin solutions and it was found that the fading progressed according to the following formula : $-{\frac {dc}{dt}}=K_c\;{\frac C{C_0}}$ where Kc is apparent light-fading rate constant relate to $C_0$. Photodecomposition of vitamin $B_6$ in aqueous multivitamin solutions was apparently first order kinetics and was stable in polyethylene>brown color>glass container to sunlight. Photodecomposition of vitamin $B_6$ in four seasons also investigated.

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The Factors Related to the Menopausal Symptoms of Married Middle-Aged Women: Focus on the Effects of Attitudes toward Menopause and Family Related Variables (기혼 중년여성의 갱년기 증상에 영향을 미치는 변인에 관한 연구 - 폐경에 대한 태도와 가족관련 변인을 중심으로 -)

  • Kim, Eunkyung;Lee, Kyung-Hae
    • Korean Journal of Human Ecology
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    • v.21 no.6
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    • pp.1043-1058
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    • 2012
  • The purpose of this study was to identify how attitudes toward menopause and family-related variables (living with a first child, satisfaction with children, and marital satisfaction) were associated with the perceived menopausal symptoms of middle-aged Korean females. Data for the study were based on a community sample of 628 women whose ages ranged from 45 to 60, who were currently married and had at least one child. The respondents reported lower levels of menopausal symptoms, medium levels of marital satisfaction and slightly higher levels of satisfaction with children. Feelings of tiredness, irritability, and nervousness without apparent reason, and aches in the lumbago and joints were common menopausal symptoms reported in this study. Regression analysis was conducted to investigate the effects of monthly income, educational level, employment status, attitudes toward menopause, living with a first child, satisfaction with children, and marital satisfaction on perceived menopausal symptoms. Attitudes toward menopause, living with a first child, satisfaction with children and marital satisfaction were significantly associated with perceived menopausal symptoms. In particular, marital satisfaction had the strongest effect on perceived menopausal symptoms. The results showed that in the face of the developmental challenges experienced during the menopausal transition, family-related variables served as positive reinforcement for married middle-aged women. This finding suggests that in order to improve the menopausal transition, family education programs need to be developed and offered to middle aged females who suffer from severe menopausal symptoms.

Modeling on the Sorption Kinetics of Lead and Cadmium onto Natural Sediments (퇴적물에서의 납과 카드뮴의 흡착 동력학 모델링)

  • Kwak, Mun-Yong;Ko, Seok-Oh;Park, Jae-Woo;Jeong, Yeon-Gu;Shin, Won-Sik
    • Korean Journal of Ecology and Environment
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    • v.39 no.4 s.118
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    • pp.450-461
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    • 2006
  • In this study, sorption kinetics of lead (Pb) and cadmium (Cd) onto coastal sediments were investigated at pH 5.5 using laboratory batch adsorbers. Four different models: one-site mass transfer model (OSMTM), pseudo-first-order kinetic model (PFOKM) ,pseudo-second-order kinetic model (PSOKM) and two compartment first-order kinetic model (TCFOKM) were used to analyze the sorption kinetics. As expected from the number of model parameters involved, the three-parameter TCFOKM was better than the two-parameter OSMTM, PFOKM and PSOKM in describing sorption kinetics of Pb and Cd onto sediments. Most sorption of Pb and Cd was rapidly completed within the first three hours, followed by slow sorption in the subsequent period of sorption. All models predicted that the sorbed amount at the apparent sorption ($q_{e,s}$) equilibria increased as the CEC and surface area of the sediments increased, regardless of initial spiking concentration ($C_0$) and heavy metal and the sediment type. The sorption rate constant ($k_s,\;hr^{-1}$) in OSMTM also increased as the CEC and BET surface area increased. The rate constant of pseudo-first-order sorption ($k_{p1,s},\;hr^{-1}$) in PFOKM were not correlated with sediment characteristics. The results of PSOKM analysis showed that the rate constant of pseudo-second-order sorption ($k_{p2,s},\;g\;mmol^{-1}\;hr^{-1}$) and the initial sorption rate ($v_{o,s},\;mg\;g^{-1}\;hr^{-1}$) were not correlated with sediment characteristics. The fast sorption fraction ($f_{1,s}$) in TCFOKM increased as CEC and BET surface increased regardless of initial aqueous phase concentrations. The sorption rate constant of fast fraction ($k_{1,s}=10^{0.1}-10^{1.0}\;hr^{-1}$) was much greater than that of slow sorption fraction ($k_{2,s}=10^{-2}-10^{-4}\;hr^{-1}$) respectively.

A Study on the Design Characteristics and the Origin of Three-story Section in the Unite d'Habitation at Marseilles (마르세이유 거대 주거동의 건축설계 특성(特性)과 단면 3층 단위체 기원(起源)에 관한 연구(硏究))

  • Yoon, Chae-Shin
    • Journal of architectural history
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    • v.7 no.4 s.17
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    • pp.61-75
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    • 1998
  • The Unite d'Habitation at Marseilles was an experimental project that Le Corbusier had been waiting for since 1920s in order to explore his ideals and visions in mass housing and city planning. As a leader of the first generation members in CIAM, Le Corbusier tried to give a new form and an order to the Unite d'Habitation at Marseilles in both building design and city planning level. The purpose of this research is to investigate the design characteristics of the Unite d'Habitation at Marseilles in three different levels of built environment with a particular emphasis on the process through which an original form is derived from its contextual settings. In the level of city planning, Le Corbusier aimed to reshape traditional low-rise urban housing by deploying several Unites spaciously. Le Corbusier believed that the spacious deployment of Unites would bring us both the functional economy in the city and the natural amenity in the suburbs. As Unite d'Habitation would be called frequently as vertical garden city, the influence of suburban garden city on Unite d'Habitation is apparent. In the building level, the binomial harmony of individual-collectivity was pursued by providing three different public floors and by combining 23 different family unit types in the Unite d'Habitation at Marseilles. In order to visualize the concept of object-type, family units were prefabricated and inserted into the structural frame of the Unite d'Habitation at Marseilles. Two family units are combined to make a three-story section with street corridor in the middle. This three-story section unit is very original as it has access corridor every third floor and each unit could have considerable depth with the help of the living space of two story height. In consideration of formal and plan similarity as well as contextual edivdence, it is concluded that the three-story section of the Unite d'Habitation is derived more from Narkomfin Apartments than from the monastery at Ema or Immuble Villas.

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Drug Release Characteristics and Skin Irritancies of Topical Gels and Multiple Emulsion Creams Containing Kojic Acid (외용겔 및 다중유제크림의 코지산 방출특성과 피부자극성)

  • Yu, Sung-Un;Park, Eun-Woo;Choi, Young-Wook
    • Journal of Pharmaceutical Investigation
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    • v.28 no.2
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    • pp.87-92
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    • 1998
  • Kojic acid (KA) is an antimelanogenic agent which has been widely used in cosmetics to whiten the skin color. However, it has the drawbacks of the skin irritancy and the instability against the pH, temperature, and light. In order to overcome these problems, various topical gels and multiple emulsion creams which can control the release of active ingredient, KA, were formulated employing cream bases of mineral oil with caprylic capric triglyceride and hydrophilic polymers such as chitosan, carbopol. and pluronics. Using Franz diffusion cells mounted with a synthetic cellulose membrane (MWCO 12,000), drug release characteristics of the formulations were evaluated by the HPLC assay of KA concentration in the receptor compartment of pH 7.4 phosphate buffered saline solution. Drug release from chitosan-based gels (ChitoGel) obeyed to the first order kinetics with a rapid release especially in the initial period. However, pluronic-based gels (PluGel) and carbopol-based gels (CarboGel) revealed controlled release of drug to some extent, followed by the square root-time kinetics. Moreover, the release of KA was further controlled with the W/O/W multiple emulsion creams (MultiCream), showing the apparent zero order release kinetics by virtue of dynamic ratecontrolling membrane of the oil layer. The flux $(J,\;{\mu}g/cm^2/hr)$ of ChitoGel. CarboGel. PluGel. and MultiCream in the initial period of 6hr were 73.30, 28.67. 24.04 and 7.72, respectively. On the other hand, the skin irritancy score of ChitoGel and MultiCream were observed as 2.5 and 2.3 respectively, in the rabbit skin irritation test. Although there were insignificant differences at p<0.05 between those formulations, it was possible to conclude that the W/O/W multiple emulsion creams containing KA might be a good candidate for an antimelanogenic drug delivery system due to the controlled release of acidic drug molecules.

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