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1.

1. 1. The authors propose humidity reduction instead of lowering room temperature in order to reduce cooling syndrome.

2. 2. They conducted experiments with subjects in the rooms, one with controlling humidity to about 40% r.h. and another without humidity control. Air-conditioning system with humidity control has a greater promise in making a comfortable environment, even at the temperature as high as 30°C, in comparison with conventional means using temperature control alone.

3. 3. Relationship of actual mean votes on temperature sensation and comfort sensation with PMV and SET, respectively, suggests that Japanese people might be more sensitive to humidity than Westerners and so different methods from those used in the western countries should be required for human thermal environmental studies with respect to the hot humid summer in Japan.

Author Keywords: Subjective experiments; thermal sensations; humidity reduction; thermal indices; hot humid climate  相似文献   


2.
Summary An integrated computerized control system, consisting of temperature and moisture sensors, a variable relative humidity air stream and water sprayers was used to control temperature and moisture in the solid substrate fermentation of extruded corn withRhizopus oligosporus in a 15 l rotary drum fermenter. Dry air was blown through the substrate to force evaporative cooling, balanced by spraying of cold water to maintain constant moisture.  相似文献   

3.
We report a fully integrated, portable, battery-operated electronic nose system comprising a bio-inspired two-layer multiple-walled carbon nanotube (MWNT)-polymer composite sensor array, a bio-inspired fast-adaptive readout circuit, and a microprocessor embedded with a pattern recognition algorithm. The two-layer MWNT-polymer composite sensor is simple to operate, and the membrane quality can be easily controlled. These two-layer membranes have improved sensitivity and stability. The fast-adaptive readout circuit responds to the sensor response, while tuning out the long-term constant background humidity, temperature, and odors. This portable electronic nose system successfully classified four complex alcohol samples 40 times for each sample; these samples were sake, sorghum liquor, medical liquor, and whisky.  相似文献   

4.
Summary A digital registration system used with temperature- and humidity-controlled cuvettes for net photosynthesis and transpiration measurements in the field is described. The associated errors of the measured parameters and calculated data are estimated. The digitalization is based on an analogue registration which is of primary importance in the control of experimental conditions in the cuvettes. The digital system is connected to the analogue registration in series. The error associated with digitalization is 0.1% across 70% of the scale. This error increases to 0.2% between 3 and 30% on the scale due to a minor lack of linearity. The reproducibility of the digitalization is ±0.024%.The error associated with data transfer in the digitalization and the errors of the analogue registration are estimated for temperature and humidity measurements (error of air and leaf temperature is ±0.1° C; error of the dew point temperature is ±1.1° C dew point). The effect of these errors on the calculation of relative humidity and the water vapour difference between the leaf and the air is determined using the progressive error law. At 30° C and 50% relative humidity, the error in relative humidity is ±7.4%, the error for the water vapour difference is ±6.6%. The dependence of these errors on temperature and humidity is shown.The instrument error of the net photosynthesis measurement is calculated to be ±4.2%. Transpiration measurements have an average inaccuracy of ±8.3%. The total diffusion resistance which is calculated from values of transpiration and the water vapour difference has an average error of ±10.9%. The sizeable influence of errors in humidity and temperature measurements on the calculated diffusion resistance is demonstrated. The additional influence of biological errors associated with field measurements is discussed.  相似文献   

5.
为实现自动控制蚯蚓生物处理反应器处理城市污泥过程中温度和相对湿度, 采用SVM(support vector machine)技术结合MPC(model predictive control)模型控制技术建立自动控制模型,准确调节蚯蚓反应器内强耦合的温度和相对湿度,在预定时间有效地控制实际温度和相对湿度达到预设目标。  相似文献   

6.
本文在生物学特性研究的基础上,组建了苹果绵蚜(Eriosoma lanigerum)及其日光蜂(Aphelinus mali)寄主——天敌作用系统的Boxcar train模型,对苹果绵蚜猖獗期的二种群数量进行了模拟,其结果与果园调查基本吻合。用此模型做系统的灵敏度分析,结果表明系统的内部因子(如蚜蜂的基数比例)和外部因子(温湿度)对系统均有影响。温度升高,二种群数量增加,反之则下降。湿度增加,苹果绵蚜日光蜂种群数量上升,反之则下降。湿度变化对苹果绵蚜无不良影响。比较而言,温度对系统的影响比湿度大得多。减少苹果绵蚜基数比增加日光蜂基数对系统的影响大,据此可从理论上估计生物防治的局限性。  相似文献   

7.
城市河道绿带宽度对空气温湿度的影响   总被引:1,自引:0,他引:1       下载免费PDF全文
以北京市北五环清河旁侧8段不同宽度的绿带为研究对象, 分别对样地和对照样地的气温和相对湿度进行同步测定, 每2 h测定一次, 每个季节连续测定7天。结果显示: 绿带在春、夏、秋季具有增湿降温效应, 并且此效应随着绿带宽度的增加而不断增强, 夏季的增湿降温效应最强, 春、秋季节的增湿降温效应差别不大; 绿带在冬季具有保温增湿效应, 随着绿带宽度的增加, 保温效应不断增强, 增湿效应不断减弱。四季中, 绿带温湿度变化受环境温度的影响较大, 在一天中的14:00-16:00时段, 春、夏、秋季增湿降温效应最强; 在此时段冬季的保温效应最弱, 增湿效应最强。  相似文献   

8.
采用LI-6400型便携式光合仪测定了扬州古运河风光带不同绿地类型气温及空气相对湿度的日变化。在夏季7:30至16:30,乔-草型和灌-草型绿地的气温均随时间推移而上升,最高值出现在12:00,但各时段的气温均低于对照点(园路)。绿地内的空气相对湿度随时间推移呈梯度下降的趋势,但绿地内的空气相对湿度明显高于对照点。研究结果表明,与对照点相比,2种绿地类型均具有明显的降温增湿效应,且乔-草型绿地的降温增湿效应优于灌-草型绿地。此外,乔-草型绿地的垂柳(Salix babylonica L.)林中,距林地中心越远,林地的降温增湿效应越弱。  相似文献   

9.
目的:研究在高温高湿应激状态下拉西地平对葡萄糖调节蛋白(glucose-regulated protein78,GRP78)和C/EBP环磷酸腺苷反应元件结合转录因子同源蛋白(C/EBP-homologous protein,CHOP)在大鼠心肌中表达及对心室重塑的影响。方法:将30只雄性Sprague-Dawly(SD)大鼠随机分为对照组、高温高湿组、拉西地平干预组,每组10只。喂养6周后颈动脉插管测定平均动脉压及心率。B超检测左室形态结构。免疫组化法检测大鼠心肌GRP78及CHOP蛋白及表达水平。结果:高温高湿组的大鼠平均动脉压(MBP)、隔厚度(IVST)、左室后壁厚度(LPWT)、左室重量指数(LVWI),GRP78及CHOP蛋白表达水平与对照组相比均有显著升高(p<0.01),拉西地平干预组能显著降低大鼠平均动脉压(MBP)、室间隔厚度(IVST)、左室重量指数(LVWI),GRP78及CHOP蛋白的表达水平(p<0.05)。结论:内质网应激可能参与了高温高湿诱导的左室重构;拉西地平可能通过降低GRP78及CHOP的表达干预了ERS介导的心肌肥厚通路,从而改善心脏功能。  相似文献   

10.
Temperature-controlled open-top chambers for global change research   总被引:6,自引:0,他引:6  
To enable experiments on the interactive effects of elevated atmospheric CO2 and increased air temperature on physiological processes in trees to be carried out, we altered the standard design of open-top chambers by replacing blowers with evaporative coolers and in-line heaters, with a feedback control system to maintain ambient or elevated air temperatures within the chambers. Ambient and elevated (+ 4 °C) temperature regimes were attained consistently and reliably throughout the growing season, with high reproducibility between chambers. From May through December the average of nearly 300,000 temperature measurements was 18.5 °C in ambient air, 18.9 ± 0.6 °C in six ambient chambers, and 22.4 ± 0.9 °C in six elevated temperature chambers. The difference in soil temperature between ambient and elevated chambers was 1.2 °C. Absolute humidity (vapour pressure) in the chambers was higher than that of ambient air, but it was generally similar between temperature treatments. Vapour pressure deficit therefore was higher in elevated temperature chambers than in ambient chambers, and this difference is considered an inseparable part of the temperature treatment. The addition of a temperature control system to open-top chambers removes what has been an important flaw in this important tool for global change research.  相似文献   

11.
Cotton leaf curl virus disease reduces the cotton yield significantly every year and is transmitted by Bemisia tabaci. The study was designed to evaluate 15 varieties/lines against the disease. Multiple regression analysis was performed based on a-biotic environmental variables (maximum air temperature, minimum air temperature, relative humidity and rainfall) to predict disease incidence and its vector (Bemisia tabaci). Two bio-products were evaluated against the whitefly population to control the disease. Out of 15 cotton varieties/lines, no one was found highly resistant against the disease. Five varieties/lines (BT BT-980, BT-457, KIRAN, BT-666 and SLH-BT-6) exhibited moderately resistant response. Maximum air temperature (34–35.5 °C), minimum temperature (25.75–26.25 °C), relative humidity (64.14–66%), rainfall (1–2 mm) and wind speed (5.50–5.75 Kmh?1) favoured the disease development. Maximum whitefly population was favoured by maximum air temperature from 34–35.5 °C, 25.8–26.2 °C minimum air temperature, 64.14–66% relative humidity, 1–2 mm from rainfall and 5.50–5.75 Kmh?1 wind speed. Datura stramonium was found more effective as compared to Aviara (Homoeopathic) but not from the positive control (Acetamiprid).  相似文献   

12.
在同一湿度(53%RH)不同温度(14℃、17℃、20℃、23℃、26℃、29℃、32℃、35℃及同一温度(26℃)不同湿度(30%RH、53%RH、75.5%RH、85%RH、92.5%RH、100%RH)组合条件下,测定了温湿度对番茄刺皮瘿螨Aculops lycopersici (Massee)生长发育及繁殖的影响。结果表明,温、湿度对该螨存活率有明显影响,以23℃(53%RH)和75.5%RH(26℃)条件下最高,分别为89.9%和87.1%; 其发育历期较短,在14~35℃和30%~100%RH范围内,历期随温度升高而缩短,随湿度升高而延长; 番茄刺皮瘿螨的发育起点温度较高,卵、若螨和整个世代的发育起点温度分别为10.51、9.02和9.15℃。完成一代需要105.56日·度。温湿度对番茄刺皮瘿螨的繁殖力有明显影响,产卵期随温度升高而缩短,随湿度升高而延长; 产卵量在26℃(53%RH)和53%RH(26℃)下最高,每头雌虫产卵分别为44.3粒和42.2粒; 26℃(53%RH)和53%RH(26℃)条件下种群的内禀增长率最高,分别为0.2645和0.2669。结果表明,适宜的温湿度条件为温度26~29℃、相对湿度53%~75%。  相似文献   

13.
With respect to the limitations use of methyl bromide and phosphine, employing ionizing radiation to control stored product pests has attracted great attention. The aim of this study is the investigation of the combined effects of gamma irradiation as viable alternatives to synthetic insecticides and environmental management on mortality and sterility of Rhyzopertha dominica (Fabricius) in a wheat cultivar (Gascogen). The effect of doses range from 30 to 2000?Gy gamma irradiation in combination with manipulation of temperature (15, 21, 27 and 32?°C) and relative humidity (20%, 50%, 65% and 85%) on 5–10?days old adults of R. dominica in Gascogen cultivar of wheat were explored. The experiments were repeated three times and conducted in The Nuclear Agriculture Research School in Karaj and laboratory of shahid steki silo in shahre-kord. Probit analysis revealed that both temperature and relative humidity had combined effects when used with gamma irradiation. The lowest doses of gamma ray required to kill 25% (14.2?Gy) and 50% (610.8?Gy) of the population (LD25 and LD50) were recorded at 21?°C and 85% relative humidity respectively. The low dose for 99% mortality (LD99; 2386.7?Gy) was recorded for beetles maintained at 21?°C and 50% relative humidity. The effect of temperature (15, 21, 27 and 32?°C) on sterility caused by gamma irradiation was also investigated. The results showed that the F1 generation emerged only when the beetles were treated with doses of 0–100?Gy at 32?°C and 0–70?Gy at 27?°C. These results indicate that temperature and relative humidity play an important role in the susceptibility of the lesser grain beetle to gamma irradiation. The results suggest that controlling the efficiency of gamma radiation through environmental control allows the use of low doses of gamma radiation that have a less harmful effect on human health, non-target organisms and seed agronomic features.  相似文献   

14.
飞虱虫疠霉继发性感染对桃蚜数量增长的控制作用   总被引:1,自引:0,他引:1  
冯明光  徐均焕 《应用生态学报》2002,13(11):1433-1436
用飞虱虫疠霉(Pandora delphaics)“孢子浴”接种的桃蚜(Myzus persicae)无翅成蚜在离体甘蓝菜叶片(65cm^2)上建立蚜群,在不同温度(10-30℃)和湿度(74%-100%RH)的组合条件下任其繁衍,发病和交互感染,以评价该菌的控蚜效果。在25个温,湿度组合处理(8次重复,每重复含3头接种成蚜)中,蚜群均不同程度的发病死亡,在历时30d的观察中,以高温(20-30℃),高湿(95%RH)组合条件下的蚜群发病快且死亡率高,蚜尸上产生的孢子有效地引起若蚜继发性感染。与相同温度下不带菌的对照蚜群相比,次于30℃下,各湿度除个别例外,第8d的控蚜率达30%以上,第20d达80%以上。在10℃和15℃下,控蚜效果一般不如上述较高温度下,且与湿度的关联程度相对较低,但最大控蚜效果均发生在100%RH处理中。结果表明,飞虱虫疠霉用于蚜虫防治的潜力很大,值得深入研究和开发利用。  相似文献   

15.
A controlled environment system, termed the Phyto-Nutri-Tron (PNT), has been established to study whole plant ecophysiological responses to multiple environmental factors. The PNT is a computer-controlled highly flexible growth facility with independent control of the shoot and the root environment. The facility consists of two growth cabinets each containing four separate hydroponic growth systems. The growth cabinets can be used as assimilation chambers with individual control of temperature, humidity, light, CO2 and monitoring of O2. The hydroponic growth systems are connected to nutrient supply units with disinfection systems and individual control of temperature, pH and oxygen. The ionic composition of the solutions has automated feedback control through a PO4 autoanalyzer and a flow injection analyzer which also analyzes NH4+, NO2- and NO3-. Other ions are automatically monitored by ICP-AES. The system has automated calibration procedures of the analytical equipment and prolonged studies of plant growth can be performed under constant environmental conditions. This paper describes the design and construction of the PNT, the results of a number of tests showing the degree of control of environmental factors and the results of a comparative study on NH4+ and NO3- uptake kinetics by Juncus effusus conducted in the PNT demonstrate the use of the PNT in ecophysiological studies.  相似文献   

16.
We tested the hypothesis that differences in temperature and desiccation tolerances of eggs of the container-dwelling mosquitoes Aedes albopictus and Aedes aegypti influence whether invading A. albopictus coexist with or exclude A. aegypti in Florida. In the laboratory, egg mortality through 30 days for A. albopictus was strongly temperature and humidity dependent, with low humidity and high temperature producing greatest mortality. In contrast, mortality through 30 days and through 60 days for A. aegypti was very low and independent of temperature and humidity. Mortality through 90 days for A. aegypti showed significant effects of both temperature and humidity. In the field, the proportion of vases occupied by A. albopictus was significantly lower at four of six sites at the start of the wet season (after a dry period) versus well into the wet season (after containers had held water for weeks). The proportion of vases occupied by A. aegypti was independent of when during the wet season vases were sampled. These results imply that dry periods cause disproportionately greater mortality of A. albopictus eggs compared to A. aegypti eggs. Container occupancy at tire and cemetery sites was significantly related to two principal components derived from long-term average climate data. Occupancy of containers by A. albopictus was greatest at cool sites with little or no dry season, and decreased significantly with increasing mean temperature and increasing number of dry months. In contrast, occupancy of containers by A. aegypti was lowest at cool sites with little or no dry season, and increased significantly with increasing mean temperature and increasing dry season length, and decreased significantly with total precipitation and number of wet months. We suggest that local coexistence of these species is possible because warm, dry climates favor A. aegypti and alleviate effects of competition from A. albopictus via differential mortality of A. albopictus eggs.  相似文献   

17.
This study investigated the influence of season, temperature, and humidity on the reproductive performance of sows under tropical conditions. Data were collected from 11 sow herds from January 2001 to June 2002. Temperature and humidity were recorded daily for each herd from January 2001 to February 2002. Semen used was collected from boars housed in conventional open-air stables (six herds) or in evaporative cooling stables (five herds). A total of 43,875 farrowing records were included in the statistical analysis. Fourteen-day moving averages of daily maximum temperature and minimum humidity were calculated and merged with each reproductive record. ANOVA was applied to the reproductive records. In addition to the fixed effects included in the statistical models (e.g. system, season, parity, temperature, and humidity), the random effect of herd within system was included. The total number of piglets born was analyzed in relation to the climate at previous weaning (NTB-w), at mating (NTB-m), and at farrowing (NTB-f). The housing system of the boars had no significant effect on any of the reproductive variables analyzed. Season (2-month periods) as well as parity number had a significant effect on all reproductive variables analyzed. Increased length of previous lactation had a significant and favorable effect (P < 0.001) on NTB-w, NTB-m, and weaning-to-first-service interval. There were indications that high temperature and humidity (recorded at the herd level) at previous weaning/mating or at farrowing had negative effects on litter size, but these negative influences were not consistent.  相似文献   

18.
Solid state electrolysis experiments were performed on the biomolecules, hemoglobin, cytochromec, collagen, lecithin and melanin at various hydration states; and for hemoglobin at various solvation states with methanol adsorbate. The evolved hydrogen was measured and compared with theoretical (Faraday's Law) expectations for the known amount of charge passed through the adsorbents. The difference between the theoretical and actual is a measure of the contributions of electronic charge carriers to the total current. Thus the protonic/electronic conduction ratios are determined.All biomolecules tested appear to be mixed semiconductors. That is, both electronic and protonic charge carriers make significant contributions to the currents over hydration ranges from 6% to above 50%. The constant temperature conductivity increases exponentially with hydration (solvation) but the ratio of protonic to electronic conduction increases linearly with hydration for the globular proteins, hemoglobin and cytochromec. The fibrous protein, collagen, may be a protonic semiconductor in the dry state, with an electronic component that increases linearly with hydration. The hemoglobin-methanol system shows only electronic conductivity below 2 BET monolayers, with a sharp onset to 70% protonic conductivity above this value. This result is similar to the DNA-water system previously reported. The protonic/electronic ratio in hydrated hemoglobin may be a function of the applied voltage; being predominantly electronic below 30 volts (300 volts/cm), and a constant mixed value above 100 volts (1000 volts/cm). Our results suggest that both electronic and protonic conduction are intrinsic processes in these substances and subject to control by a number of techniques.  相似文献   

19.
小叶榕气生根气体交换特征及影响因子研究   总被引:1,自引:0,他引:1  
用LI-6400XT便携式光合仪测定了小叶榕(Ficus microcarpa L. f.)气生根的气体交换特征。结果表明气生根具有呼吸、蒸腾作用和空气吸湿作用。影响气生根呼吸作用的因素为年龄>空气温度>光强>相对湿度;影响蒸腾作用的因素为年龄>相对湿度>空气温度>光照。年龄小的气生根的呼吸和蒸腾作用较强,年龄大的尤其是木质化程度较高的气生根的呼吸作用较小,水分的释放(蒸腾作用)转变为水分的吸收(吸湿作用)。年龄小的气生根的CO2交换率与温度呈线性关系,温度越高,CO2交换率越大,呼吸越强;H2O交换率与相对湿度呈线性关系,相对湿度越大,H2O交换率越小,蒸腾越弱;年龄大的成熟气生根的H2O交换率与空气相对湿度呈线性关系,相对湿度越大,H2O交换率越小,蒸腾越小。  相似文献   

20.
温湿度对稻纵卷叶螟卵的联合作用   总被引:1,自引:0,他引:1  
为了探讨温湿度在稻纵卷叶螟Cnaphalocrocis medinalis (Guenée)种群发展中的作用, 通过室内实验调查了不同温度和湿度组合下该蛾卵的发育历期、 胚胎发育情况、 孵化率和卵粒重量的变化。结果表明: 在相同温度下卵历期随相对湿度的增大而缩短, 孵化率随相对湿度的加大而提高。在22℃下低于46%的相对湿度显著降低了卵的孵化率, 而在25~34℃下低于66%的相对湿度会引起孵化率的显著降低, 37℃下卵无论在何种湿度中均不能孵化。在50%左右的低湿条件下, 温度高于28℃后卵也不能孵化。温度在22~31℃和相对湿度在77%~100%范围内, 卵的孵化率无显著差异, 这属于稻纵卷叶螟卵的适宜温湿度范围。稻纵卷叶螟卵的发育起点温度和有效积温分别为10.1±0.6℃和63.7±3.5日度。卵的孵化率(Y)与温湿系数(RH/T)间呈显著的逻辑斯蒂曲线关系Y=0.8662/[1+exp(17.4084-7.5714×RH/T)]。温湿系数在2.34以下时卵孵化率将低于50%, 而达到3.0左右时孵化率接近最高值。结论认为, 低湿造成的稻纵卷叶螟卵重量显著降低、 卵粒干瘪、 胚胎发育受阻是致死卵的主要原因。  相似文献   

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