• 제목/요약/키워드: High humidity

검색결과 1,705건 처리시간 0.034초

A Study on the Plasma Biochemical Indices of Heat-Stressed Broilers

  • Lin, H.;Du, R.;Gu, X.H.;Li, F.C.;Zhang, Z.Y.
    • Asian-Australasian Journal of Animal Sciences
    • /
    • 제13권9호
    • /
    • pp.1210-1218
    • /
    • 2000
  • Four experiments were conducted to evaluate the effect of temperature and humidity on biochemical indices of Arbor Acres broilers at different weeks of age. The alkaline phosphatase (AKP), acid phosphatase (ACP), lactic dehydrogenase (LD), creatine kinase (CK), plasma glucose (Glu), calcium (Ca), potassium (K), chloride (Cl), urea nitrogen (UN), uric acid (UA), plasma thyroxin (T4), triiodothyronine (T3) and insulin levels were determined in all the four experiments. In experiment 1, the plasma Glu, LD and CK levels were increased by heat exposure ($35{^{\circ}C}$ and 35, 60, or 85% RH, 2 h) and this effect was aggravated by longer exposure (24 h). No significant changes (p>0.05) were found in Ca concentration, activity of AKP and ACP. In experiment 2, temperature (10, 20, 30, $33{^{\circ}C}$) had significant effect on the levels of K, Cl, UN, UA levels and the activity of LD (p<0.01), but had no significant influence on the activity of CK (p>0.05). The UN, UK and LD levels were elevated by low temperature $(10{^{\circ}C})$ (p<0.01), Cl content was increased by high temperature ($(33{^{\circ}C})$ (p<0.01), and K level was decreased by high ($(33{^{\circ}C})$ or low $(10{^{\circ}C})$ temperature and increased by medium temperature $(30{^{\circ}C})$ (p<0.01). The humidity (35, 85% RH) only had significant effect on Cl concentration which was decreased by high humidity (p<0.01). In experiment 3, the result showed that only the LD and CK activity were significantly increased (p<0.01) by high temperature (7, 24, 28, $32{^{\circ}C}$) or high humidity (35, 85% RH). Temperature and humidity had no significant effect on K, Cl, UA, UN and Glu levels (p>0.05). In experiment 4 (24, 27, 30, $33{^{\circ}C}$; 30, 45, 60, 75, 90% RH), plasma T3 level was declined by high temperature $(33{^{\circ}C})$, and this phenomena disappeared in birds under high temperature and high humidity environment. T4 concentration in plasma was not affected by temperature (p>0.05), but was increased by high or low humidity (p<0.01). Neither temperature nor humidity had significant effect on plasma insulin concentration (p>0.05). The results of the four experiments suggested that broilers at different growth periods might have different thermal requirements and would response differently to heat exposure. The plasma biochemical indices themselves had big variation; the reaction of the indices to thermal exposure treatment differed with the age of broilers. The big variation of biochemical indices themselves might cover the response of indices to temperature and humidity treatments.

Implications of High Temperature and Low Humidity on the Hatching in the Silkworm, Bombyx mori L. Under LD 12 : 12 Condition

  • Reddy P. Lakshminarayana;Naik S. Sankar;Reddy N. Sivarami
    • International Journal of Industrial Entomology and Biomaterials
    • /
    • 제11권2호
    • /
    • pp.139-143
    • /
    • 2005
  • The implications of temperature (25, 30 and $35^{\circ}C$) and relative humidity (RH; 60, 70 and $80\%$) on the hatching rhythmicity and hatching parameters (percentage and duration) were studied in the silkworm, Bombyx mori L. under natural photoperiod (LD 12 : 12). Disease free layings (DFLs) of two pure silkworm breeds, Pure Mysore (PM, a multivoltine breed) and $NB_4D_2$ (a bivoltine breed), and their hybrid, $PM{\times}NB_4D_2$ were introduced into the experimental conditions on the $3^{rd}$ day of oviposition till completion of hatching. The hatching rhythm was predominantly diurnal under all temperature and humidity conditions, with peaks just after 'lights-on' phase (6 hrs). Extreme temperature and humidity conditions did not alter the hatching rhythmicity, but prolonged the hatching durations, extending it to the next day, coupled with reduced hatching percentage in PM and $PM{\times}NB_4D_2{\cdot}In\;NB_4D_2$, on the other hand, hatching did not extend to the next day. Hatching percentage in this breed, however, reduced below the economic level under high temperature and low humidity conditions. The high temperature and low humidity together, though did not alter the rhythmicity, seems to exert synergetic effect on the hatching percentage and its duration in the silkworm, B. mori.

황색종 연초 건조중 황변기 온습도차가 잎담배 색상 및 화학성분에 미치는 영향 (EFFECT OF TEMPERATURE AND HUMIDITY ON THE LEAF COLOR AND CHEMICAL COMPONENTS DURING THE YELLOWING STAGE OF FLUE-CURING)

  • 황건중;석영선;이한석
    • 한국연초학회지
    • /
    • 제7권2호
    • /
    • pp.129-139
    • /
    • 1985
  • cent was carried out to study on the effect of temperature and humidity to chemical tobacco leaves during the yellowing stage. The results were follows : In the condition of high humidity and low temperature, yellowing time was delayed ; leaf color appeared lack clearness. In the higher temperature and the lower humidity during the yellowing stage : total sugar, reducing sugar and malic acid content were increased. Decomposition of nitrogenous components elevated in $38^{\circ}C$, 85%RH. Changes of total nitrogen content correlated with total curing time. Adecrease of linolenic acid with a corresponding increase of chlorogenic acid proceeded in the condition of low temperature and high humidity. In a view of tobacco quality by chemical components, the low temperature and high humidity during the yellowing stage decreased quality of tobacco leaves. It is considered to control of the proper condition of temperature and humidity during the yellowing.

  • PDF

습도 및 미끄럼 속도에 따른 질화규소의 마찰 마모 특성에 관한 연구 (Effects of Humidity and Sliding Speed on the Wear Properties of $Si_3N_4$ Ceramics)

  • 이기현;김경웅
    • Tribology and Lubricants
    • /
    • 제9권2호
    • /
    • pp.63-69
    • /
    • 1993
  • The wear properties of two types of $Si_3N_4$(silicon nitride) exposed to high and low humidity were examined experimentally for various sliding speed. Bearing steel was used as the disk material at pin-on-disk type sliding. Wear rates of pressureless sintered-plus-hot-isostatic pressed Si3N4 were slightly lower than those of pressureless sintered $Si_3N_4$. It was observed that adsorbed moisture and sliding speed markedly influenced the wear properties of $Si_3N_4$. The highest wear rate was obtained under the high humidity and low sliding speed condition. As the sliding speed was increased, wear rates were decreased and the humidity effect on the wear rates of $Si_3N_4$ was lowered. The result that the $Si_3N_4$ pin showed a high wear rate under the high humidity condition was explained by the property change due to the adsorbed moisture, plowing action by the hard particles of $Fe_2O_3$ from the disk, and the corrosion effect at $Si_3N_4$ surface. Increase in sliding speed was supposed to have reduced the humidity effect on wear rate of $Si_3N_4$ by raising the temperature of both the bearing steel disk and $Si_3N_4$ pin specimen.

유연 전자 소자용 금속 전극의 고온/고습 조건에서 기계적 피로 수명 연구 (Mechanical Fatigue Lifetime of Metal Electrode for Flexible Electronics under High Temperature and High Humidity Condition)

  • 권용욱;김병준
    • 마이크로전자및패키징학회지
    • /
    • 제27권2호
    • /
    • pp.45-51
    • /
    • 2020
  • 미래의 유연 전자 기기는 고온, 고습 환경 조건에서 사용될 수 있으며 반복적으로 굽히고 펴기를 반복하기 때문에 장기 신뢰성 확보를 위해서는 환경 조건과 반복 기계적 변형의 효과를 동시에 고려해야 한다. 본 연구에서는 전자기기에서 가장 일반적으로 사용되는 Al, Ag, Cu 전극을 유연 기판상에 진공 증착한 뒤 환경적인 요건을 상온/일반습도와 85℃/85% 습도 두 가지로 조건에서, 기계적 변형이 없는 평평한 상태와 반복적으로 굽힘 변형을 가해주는 조건의 총 4가지 환경 및 피로 복합 실험을 실시하였다. Al, Ag, Cu 전극 모두 기계적 변형이 없는 평평한 경우에 일반 환경 조건 및 고온/고습 조건 모두 10시간 동안 전기 저항 변화가 발생하지 않았다. 일반 환경 조건에서 굽힘 피로 실험을 진행한 경우, Al, Ag, Cu 전극 모두 금속의 피로 파괴 현상에 의해 10만 싸이클 이후 전기 저항이 약 400%~600% 증가하였다. 고온/고습에서 피로 실험의 경우, Al, Ag 전극은 일반 조건 피로 실험과 결과가 유사하였으나, Cu의 경우 고온/고습 피로실험의 경우 10만 싸이클 이후 전기 저항이 90000% 이상 증가하였다. 이는 부식과 기계적 피로가 동시에 발생할 경우 금속 전극에 매우 심각한 신뢰성 문제를 유발한다는 것을 의미하며, 환경 조건과 기계적 변형을 동시에 고려한 전극 소재 디자인이 필요하다는 것을 의미한다.

문화재 보존시설에서의 습도지시카드 적용성 연구 (The Application of Humidity Indicators for Environmental Measurement Apparatus of Preservation Facility)

  • 임보아;신은정;도민환
    • 보존과학연구
    • /
    • 통권30호
    • /
    • pp.47-61
    • /
    • 2009
  • Cultural heritages are affected by various environmental factors. Main factors are temperature, humidity, light and indoor air pollutants such as ozone, nitrogen oxides. Especially humidity condition is very important. Low humidity condition can cause contraction and high humidity condition can lead to growth of microorganism. This study is conducted to appraise an applicability of the Humidity Indicator which is one of the simple method for humidity control. The Humidity Indicator shows the humidity conditions through color change. Therefore, photometer was used to correctly measure the color change of Humidity Indicator. As a result of lab test, Humidity Indicators was stabilized after one hour from en exposure in a certain humidity condition and the indicators indicated clear correlations between color changes of Humidity Indicators and humidity conditions. Some Humidity Indicators which had been selected through the lab tests were applied to preservation facilities of cultural heritages and the indicators indicated closed correlations with humidity conditions in indoor of facilities.

  • PDF

습도에 따른 자동차용 마찰재의 마찰특성에 관한 연구 (Effect of Humidity on Friction Characteristics of Automotive Friction Material)

  • 김성진;최낙천;장호
    • 한국윤활학회:학술대회논문집
    • /
    • 한국윤활학회 1998년도 제28회 추계학술대회
    • /
    • pp.323-329
    • /
    • 1998
  • The effect of humidity on friction characteristics of friction materials were studied using a pad-on-disk type friction tester. Three different friction materials containing simplified ingredients were investigated by changing the solid lubricant, graphite, MoS$_2$, and $Sb_2S_3$. A friction material without solid lubricant was also examined to study the effect of ingredients in the matrix on humidity. Friction material containing graphite showed lower friction coefficient at high humidity level than other conditions, however, friction material containing MoS$_2$ indicated higher friction coefficient at initial stage under high humidity level. Friction materials without solid lubricant and with $Sb_2S_3$ were little affected by humidity conditions.

  • PDF

The Effects of Micro-Environmental Factors on the House Dust Mite

  • Jo, Wan-Je;Sohn, Jang Yeul
    • Architectural research
    • /
    • 제9권2호
    • /
    • pp.37-45
    • /
    • 2007
  • The proliferation of the House Dust Mite(HDM) is affected by temperature, humidity, ventilation, etc. Measuring temperature and humidity was performed at the very location where dust samplings take place and where they live in reality together with temperature and humidity of the ambient of the room. There has been discussion over the key environment factor of HDM survival; absolute humidity or relative humidity. It seems that relative humidity is the more important determinant for the mite's survival through the analysis of previous studies. Temperature, humidity, ventilation rate and Der P1 were measured in 4 flats in London. Mite allergen was detected in every house. Levels of Der P1 varied between <100ng/g and 22,778ng/g. Flats with high relative humidity(>50%) and poor ventilation(<0.5ach) showed higher levels of mite allergen than flats with lower humidity and adequate air change rate. Questionnaire survey was conducted and the result helped to confirm the findings from monitoring of environmental factors and the dust sampling.

양방향 반사 지연선을 이용한 무선, 무전원 SAW 기반 온, 습도 센서 개발 (Development of a Wireless, Battery-free SAW-based Temperature and Humidity Sensor incorporating a Bidirectional Reflective Delay Line)

  • 임천배;이기근
    • 대한전기학회:학술대회논문집
    • /
    • 대한전기학회 2009년도 제40회 하계학술대회
    • /
    • pp.1515_1516
    • /
    • 2009
  • A 440MHz wireless and passive surface acoustic wave (SAW) based micro-sensor was developed for simultaneous measurement of temperature and humidity. The developed sensor is composed of a SAW reflective delay lines structured by an IDT (Inter-Digital Transducer), four reflectors and humidity sensitive film (polyimide). Polyimide was dry-ecthed by RIE (Reactive Ion Etching) to obtain high roughness, which gives the large reaction area resulting in high sensitivity. In wireless testing using a network analyzer, sharp reflection peaks with high S/N ratio, small signal attenuation, and few spurious peaks were observed in the time domain. High sensitivity towards the temperature and humidiy were also observed in the large concentration range. The obtained sensitivity was $16.8^{\circ}/^{\circ}C$ for temperature sensor and $15.8^{\circ}$/%RH for humidity sensor.

  • PDF

북서태평양 명태 어장의 해황 - 2 . 기후의 특성 - (Oceanography in the Waters Adjacent to Kamchatka and Kurile islands in the Northwestern Pacific - II)

  • 한영호
    • 수산해양기술연구
    • /
    • 제13권1호
    • /
    • pp.17-25
    • /
    • 1977
  • For four calender years (1971-1974), daily observations of weather conditions (air temperature, humidity, wind speed, wind direction, cloud amount, fog, precipitation etc.) at six stations in the north western Pacific Ocean are used to calculate mean monthly values and to check extra-conditions. At Petropavlosk and Miko'skoe, where indicate the characteristics of modified continental climate, the temperature and humidity are high in summer, and Iow in winter. At A Dak and She Mya, where indicate the characteristics of warm current type maritime climate, humidity is high in all season and annual range of air temperature is nearly negligible. At Simusir and Vasi!' eva, where indicate the characteristics of cold current type maritime climate, humidity is high in all season and annual range of air temperature is $15^{\circ}C.$ As dry cooling power is relatively high in winter, working condition on deck is bad. Most of fogs are advection fog in the area of cold current type climate in summer.

  • PDF