• 제목/요약/키워드: Decrease rate

검색결과 6,181건 처리시간 0.034초

중성염이 Poly(ethylene terephthalate) 직물의 알칼리 가수분해에 미치는 영향(II) (Effects of Neutral Salts on Alkaline Hydrolysis of Poly(ethylene terephthalate) (II) - Anionic Effect -)

  • 도성국;조환
    • 한국염색가공학회지
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    • 제6권2호
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    • pp.10-16
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    • 1994
  • Neutral salts have negative or positive effects on the rates of many chemical reactions and also on the rates of acidic and alkaline hydrolysis of carboxylic esters. The direction of neutral salt effects on the hydrolysis of ester depends on the charge of esters. Neutral salts accelerate alkaline hydrolysis of esters with negative charge, but decelerate alkaline hydrolysis of esters with positive charge, and have little effect on the alkaline hydrolysis of neutral esters. It is expected that the rate of the alkaline hydrolysis of Poly(ethylene terephthalte) (PET), polymeric solid carboxylic polyester with carboxyl end group at the polymer end, is also influenced positively by neutral salts. In the present work, to clarify the mechanism of the neutral salt effect on the alkaline hydrolysis of PET, many salts with different anions like NaF, NACl, NaBr, NaI were added to the aqueous alkaline solutions. Then PET was hydrolyzed with aqueous solutions of many salts in alkali metal hydroxides under various conditions. Some conclusions obtained from the experimental results were summarized as follows. The reaction rate of the alkaline hydrolysis of PET was increased by the addition of neutral salts and In k was increased nearly linearly with the square root of ionic strength of reaction medium. This fact suggested that the ionic strength effect by Debye-Huckel and Bronsted theory was exerted on the reaction. The specific salt effect was also observed. The reaction rate was increased with the decrease in the nucleophilicity of anions of neutral salts, i.e., in the order of $F^-$ <$Cl^-$<$Br^-$<$I^-$. It was thought that the reaction rate was increased in the order of $F^-$ <$Cl^-$<$Br^-$<$I^-$. because the completion of anions with $OH^-$ for carbonyl carbon became weaker with the decrease in the nucleophilicity and with the increase in the size of anions.

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전화상담과 문자메시지 제공이 허혈성 심질환자의 금연에 미치는 효과 (Effects of a Smoking Cession Program Using Telephone Counselling and Text Messaging for Patients after Ischemic Heart Disease)

  • 김은심;최혜옥
    • 한국산학기술학회논문지
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    • 제15권12호
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    • pp.7248-7258
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    • 2014
  • 본 연구는 전화상담과 문자메시지 제공 금연프로그램이 중재 횟수를 달리한 실험군1, 실험군2와 대조군의 금연 자기효능감, 니코틴의존도, 호기일산화탄소 농도, 금연성공률에 미치는 효과를 알아보기 위한 유사실험연구로 허혈성 심질환자 60명을 대상으로 하였다. 프로그램효과를 측정한 결과, 실험군은 대조군에 비해 금연 자기효능감, 금연성공률은 유의하게 증가하였고, 니코틴의존도, 호기 일산화탄소 농도는 유의하게 감소하였다. 또한 실험군1은 실험군2에 비해 금연 자기효능감, 금연성공률은 유의하게 증가하였고, 호기 일산화탄소는 유의하게 감소하였으나, 니코틴의존도에는 유의한 차이가 없었다. 따라서 허혈성 심질환자에게 제공한 전화상담과 문자메시지 중재 금연프로그램은 금연성공률의 향상에 효과가 있으며 중재 횟수에 따라 더욱 효과가 있는 것으로 나타났다.

유우에서 포도상구균 백신과 면역증강제 투여후 우유의 체세포수 변화 및 분리된 포도상구균의 항생제 내성에 관한 조사 (Studies on variation of somatic cell in milk after administration of staphylococcus aureus vaccine and immunostimulant and antibiotics resistance of isolated staphylococcus spp in milk from dairy cow)

  • 성명숙;김규섭;김우현;박희주;배성수;권헌일
    • 한국동물위생학회지
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    • 제23권1호
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    • pp.61-69
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    • 2000
  • Thirty-one dairy cow from two farm(more than 500,000 cells/ml of bulk milk) in Kyongbuk northern province were selected because of their high somatic cell(more than 500,000 cells/ml of milk In individual cow). Each cow received. staphylococcus aureus vaccine(Labac Staph) and immunostimulant(Ultracon) by intramuscular injection to be repeated every fifteen days for S times. The present study was investigated variation of somatic cell after administration of Labac Staph and Ultracon, and antibiotics resistance of isolated staphylococcus spp from milk in selected cow. The results obtained through the survey were summarized as follows ; 1. Ten dairy cow was injected in A farm. Chronic mastitic two cow after 2rd injection was weeded out the herd. Decrease rate of somatic cell after 1st, 2nd, ,3rd, 4th and 5th administration were 41.4%, 35.6%, 56.4%, 65.4% and 36.7%, respectively. Twenty-one cow was injected in B farm. Chronic mastitic five cow after ,3rd injection was weeded out the herd. Decrease rate of somatic cell after 1st, 2nd, 3rd, 4th and 5th administration were 36.9%, 59.9%, 24.5%, 62.6% and 78.4%, respectively. 2. In A farm, isolated staphylococcus spp were identified as S hyicus 2 strains(11.8%), coagulase negative staphylococcus 15 stains(89.2%) and S epidermidis 6strain(35.3%). In B farm, isolated staphylococcus spp were identified as S aureus 19 strains(55.98%) and coagulase negative staphylococcus 15 strains (44.2%). 3. In A fm, antibiotics resistant rate of isolated staphylococcus spp was high at ampicillin, penicillin and kanamycin, and middle at neomycin, streptomycin and erythromycin. in B farm, antibiotics resistant rate was moderate at ampicillin, penicillin, gentamicin, ka-namycin, neomycin, streptomycin, erythromycin and tetracycline, and coagulase negative staphylococcus spp was moderate at streptomycin.

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기공체조프로그램이 고혈압 환자의 생리.심리적 지수에 미치는 영향 (An Effect of Qi Gong Gymnastics Program on the Physiopsychological Parameter in Essential Hypertension)

  • 이명숙;최의순
    • 대한간호학회지
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    • 제28권4호
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    • pp.856-868
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    • 1998
  • The purpose of this study is to evaluate the effects of Qigong gymnastics exercise program on the physiopsychological parameter in essential hypertension. The design of the research was a one group pretest-posttest design. A total of 20 pateints with hypertension who were from forty to sixty-five years old participated in the study. The Qigong gymnastics program was carried out twice a week for thirty minutes or forty minutes for six weeks from 22, Sep. to 31, Oct. in 1997. In order to evaluate the effect of the Qigong gymnastics program physiological parameter (blood pressure, pulse rate, FVC, FEV1, Epinephrine, Norepinephrine, Cortisol) and psychological parameter(self-efficacy, Life satisfaction) were measured before and after the exercise program. Collected data was analyzed by the paired t-test with SAS package. The result are as follows : 1) There were significant decrease in systolic blood pressure and diastolic blood pressure, but there was no significant change in pulse rate. 2) There were no significant difference in FVC and FEV1 3) There were significant decrease in epinephrine, norepinephrine and cortisol. 4) There were significant improved in general self-efficacy and life satisfaction. 5) The effect of Qigong gymnastics program by measurement time on blood pressure and pulse rate were as follows : In a systolic blood pressure was gradually significant decreased from 1 week to 6 weeks and diastolic blood pressure was significantly decreased after 4weeks. But there was no significant change in pulse rate. This results suggest that Qigong gymnastics are an appropriate nursing intervention for clients with hypertension. For further research is necessary to reevaluate the effect with a letter experimental design and longer period than 8 weeks for the Qigong gymnastics program.

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버어리종 담배 건조시 급건엽 발생방지에 관한 연구 II. 차광의 영향 (Studies on the Prevention of Excessive Drying Leaves during Burley Tobacco Curing II. Effect of the Shading Conditions on the Occurrence of Excessive Drying Leaves)

  • 배성국;임해건;김경태
    • 한국작물학회지
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    • 제32권1호
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    • pp.10-15
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    • 1987
  • Burley 21을 공시품종으로 하여 건조실은 파이프 비닐하우스를 이용하였고, 시험 I 은 차광율을 10∼90%까지 20%씩 차이를 두어서 5 처리를 하였으며, 시험 II는 흑색차광막, 차광강과 5가지 유색비닐 등으로 차광재료를 달리하여 잎담배 건조시 차광효과와 알맞은 차광재료를 달리하여 잎담배 건조시 차광효과와 알맞은 차광재료를 밝히기 위하여 본 실험을 수행하였던 바 결과를 요약하면 다음과 같다. 1. 차광량이 않을 수록 온도가 낮고 습도는 높은 경향이었다. 2. 노변 전까지의 차광효과는 엽중탈수속도를 지연시키는데 있었다. 3. 급건엽발생은 차광량이 많을 수록 적었으나 차광 70% 이상에서는 큰 차이가 없었다. 4. 품질 및 물리성은 50% 이하의 차광구에서 불량하였으나, 그 이상에서는 큰 차이가 없었다. 5. 건조시 차광량의 하한선은 70% 본다. 6. 유색비닐 중 주황색, 백색 및 자주색비닐은 흑색차광막과 충분한 대비효과를 가지고 있다. 그러나 백색비닐은 광에 의한 내구성이 가장 약하였다. 7. 가시광선의 광질 차이는 건조에 거의 영향을 미치지 않았다. 8. 흑색계통의 차광재료는 차광량은 많으나 광energy를 흡수하여 하우스 내 온도를 높이므로, 내구성이 크고 광 반재형 차광재료의 개발이 요구되었다.

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Polyacrylic Acid Sodium Salt를 혼합한 세 종류 상토에 지효성 비료의 시비 수준이 포트-멈 'Lima Honey'의 생육과 무기원소 흡수에 미치는 영향 (Effect of Application Rate of a Slow-release Fertilizer in Three Media Containing Polyacrylic Acid Sodium Salt on Growth and Nutrient Contents of Potted Chrysanthemum 'Lima Honey')

  • 최종명;왕현진
    • 생물환경조절학회지
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    • 제15권1호
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    • pp.35-46
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    • 2006
  • Objective of this research was to determine the effect of application rate of a slow release fertilizer (SRF) in three root media, peatmoss+vermiculite (1:1, v/v; PV), peatmoss+composted rice hall (1:1, v/v; PR), and peatmoss+composted pine bark (1:1, v/v; PB), on growth and nutrient contents of potted chrysanthemum 'Lima Honey'. All media contained polyacrylic acid sodium salt at a rate of $4.5g L^{-1}$. The fresh and dry weights at 43 days after transplanting did not show statistical differences among treatments in each root media. Elevated application rate of SRF increased fresh and dry weights at 80 days after transplanting in PV and PB media, but not in PR medium. Elevated application rates of SRF resulted in the increase of tissue phosphorus content and decrease of tissue Ca, Na, and Zn contents at both 43 and 80 days after transplanting. Elevated application rates of SRF resulted in the decrease of pH and increase of EC and concentrations of ${NO_3}^-$ and ${P_2O_5}^{3-}$, K, Ca, and Mg in the soil solution of PV and PR media. The trends of those in PR media were also similar except ${NO_3}^-$. The differences among treatments in EC at 80 days after transplanting were less significant as compared to those at 43 days after transplanting in three media.

Theoretical Conception of Synergistic Interactions

  • Kim, Jin-Kyu;Vladislav G. Petin
    • 환경생물
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    • 제20권4호
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    • pp.277-286
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    • 2002
  • An increase in the overall biological effect under the combined action of ionizing radiation with another inactivating agent can be explained in two ways. One is the supposition that synergism may attribute to a reduced cellular capacity of damn-ge repair after the combined action. The other is the hypothesis that synergism may be related to an additional lethal or potentially lethal damage that arises from the interaction of sublesions induced by both agents. These sublesions ave considered to be in-effective when each agent is applied separately. Based on this hypothesis, a simple mathematical model was established. The model can predict the greatest value of the synergistic effect, and the dependence of synergy on the intensity of agents applied, as well. This paper deals with the model validation and the peculiarity of simultaneous action of various factors with radiation on biological systems such as bacteriophage, bacterial spores, yeast and mammalian cells. The common rules of the synergism aye as follows. (1) For any constant rate of exposure, the synergy can be observed only within a certain temperature range. The temperature range which synergistically increases the effects of radiation is shifted to the lower temperature fer thermosensitive objects. Inside this range, there is a specific temperature that maximizes the synergistic effect. (2) A decrease in the exposure rate results in a decrease of this specific temperature to achieve the greatest synergy and vice versa. For a constant temperature at which the irradiation occurs, synergy can be observed within a certain dose rate range. Inside this range an optimal intensity of the physical agent may be indicated, which maximizes the synergy. As the exposure temperature reduces, the optimal intensity decreases and vice versa. (3) The recovery rate after combined action is decelerated due to an increased number of irreversible damages. The probability of recovery is independent of the exposure temperature for yeast cells irradiated with ionizing or UV radiation. Chemical inhibitors of cell recovery act through the formation of irreversible damage but not via damaging the recovery process itself.

흰쥐에서 Ketamine에 의한 혈압하강 (Ketamine-Induced Blood Pressure Lowering in the Rat)

  • 유선봉;김상진;이문영;강형섭;김진상
    • 한국임상수의학회지
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    • 제22권3호
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    • pp.220-227
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    • 2005
  • Although ketamine has been used in the field of anesthetic medicine for its safety and favourable respiratory effects, the cardiovascular effects of ketamine is still controversial. To clarify the action and mechanism of ketamine upon cardiovascular system, arterial blood pressure, tension of aortic ring, left ventricular developed pressure and heart rate were measured in rats, Ketamine produced two types of effects on arterial blood pressure in anesthetized rats; monophasic effect (blood pressure lowering) and biphasic effect (initial transient blood pressure increasing following sustained lowering), The ketamine-induced lowering of aterial blood pressure showed a concentration-dependent manner, inhibited by the pretreament of $MgCl_2$ and potentiated by the pretreatment of $CaCl_2$. The ketamine-induced lowering of aterial blood pressure was suppressed by the pretreatment of nifedipine, verapamil or lidocaine. In phenylephrine-precontracted endothelium intact (+E) aortic rings, ketamine sometimes caused a small enhancement of contraction ($112.5{\pm}3.6{\%}$). However, in many experiments, ketamine produced a concentration-dependent relaxation in +E aortic rings precontracted with either phenylephrine or KCl. Ketamine-induced relaxation was significantly greater in KCl-precontracted strips than phenylephrine-precontracted strips. In phenylephrine-precontracted +E aortic rings, the ketamine-induced vasorelaxation was not suppressed by endothelium removal or by the pretreatment of a nitric oxide synthase inhibitors, L-$N^G$-nitro-arginine and a guanylate cyclase inhibitors, methylene blue, suggesting that the ketamine-induced vasorelaxation is not dependent on the endothelial function. In addition, ketamine elicited an increase in left ventricular developed pressure in perfused hearts accompanied by decrease in heart rate. These results suggest that ketamine could evoke a hypotension due to vasorelaxation and decrease in heart rate in rats. The inhibitory effect of cardiovascular system might be associated with modulation of $Ca^{2+}$ homeostasis.

Haloperidol 이 심혈관계에 미치는 영향 (Experimental Studies on the Cardiovascular Effects of Haloperidol in Cat and Rabbit)

  • 안영수
    • 대한약리학회지
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    • 제11권2호
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    • pp.19-27
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    • 1975
  • Haloperidol, a butyrophenone, was synthetized by Janssen and introduced for the treatment of psychosis. Although structurally different from the phenothiazines, the butyrophenones share many of their pharmacological properties, such as inhibition of conditioned avoidance response, blocking effect of amphetamine reaction, producing catalepsy, antishock effect and protection against the lethal effects of catecholalmines. Chlorpromazine can lower the arterial blood pressure through its adrenergic blocking activity, its direct effect in relaxing vascular smooth muscle, its direct effect in depressing the myocardium and its action in a complex manner on the central nervous system. In the case of haloperidol, however, was not clarified the mechanism of lowering the blood pressure. The present paper describes the effects of haloperidol on cardiovascular system to investigate the mechanisms of its actions on the arterial blood pressure. The results are followings; 1. In anesthetized cats, intravenous administration of haloperidol and chlorpromazine in the dose of 0.1mg/kg produced a slight decrease in the blood pressure, which followed by complete recovery within $30{\sim}60$ minutes. In the dose of 3mg/kg, however, both produced an abrupt and marked decrease of the blood pressure, which followed by delayed recovery. 2. Haloperidol in the dose ranges of 0.1mg to 3.0mg/kg tended to produce the heart rate slowing in the cats, while chlorpromazine has no effect on the rate. 3. Following administration of haloperidol or chlorpromazine, epinephrine reversal in the arterial blood pressure was observed in the cat, however the responses of norepinephrine and acetylcholine were little affected. 4. In the isolated rabbit atrium the contractility was depressed by haloperidol in the doses over 0.5mg per 100ml, but the rate was not affected. In contrast, the epinephrine-induced contractility was not depressed after haloperidol treatment. However, the increased rate of atrium by epinephrine was partially blocked after haloperidol. 5. In the isolated rabbit aortic strip, epinephrine-induced contraction was blocked by haloperidol. With the above results, it may be concluded that the hypotensive effect of haloperidol was largely due to ${\alpha}$-adrenergic blocking properties and the direct effect in depressing the myocardium as well as its action on central nervous system.

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조분시멘트와 플라이애시를 조합 사용한 콘크리트의 수화발열 특성 (Generation of Hydration Heat of the Concrete Combined Coarse Particle cement and Fly ash)

  • 이충섭;백대현;차완호;권오봉;한민철;한천구
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2008년도 춘계 학술발표회 제20권1호
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    • pp.889-892
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    • 2008
  • 본 연구는 보통포틀랜드 시멘트(이하 OPC)의 제조공정 중 입도 분급에 의해 포집된 조분시멘트(이하 CC)와 저발열 혼화재료인 플라이애시(이하 FA)를 조합 치환하여 콘크리트에 미치는 수화발열특성에 대해 검토하고자 하였다. 실험은 W/B 50% 1수준에 대하여 OPC를 100% 사용한 것을 Plain 배합으로 하고, CC를 OPC에 대하여 25, 50, 75%의 3수준으로 치환하고, 혼화재로 FA를 0, 10, 20, 30, 40%의 5수준으로 치환하여 총 16배치를 계획 하였다. 실험결과로 유동성의 경우는 CC 치환율이 증가할수록 점점 감소하는 경향을 나타냈고, FA의 치환율이 증가할수록 증가하였다. CC 및 FA 치환율 별간이단열에 의한 온도 상승량은 치환율이 증가할수록 감소하였는데, 특히 FA40의 경우 CC치환율에 관계없이 최대 피크온도가 $7.3{\sim}8.9^{\circ}C$로 45%정도 아주 낮게 나타났다. 초기 압축강도는 CC 및 FA치환율 증가에 따라 비례적으로 저하하였는데, 재령경과에 따라 강도저하 폭은 감소하는 것으로 나타났다.

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