Bruise Development Measurement in Apples Using Thermal Imaging Technique

In this paper, the working principle of static protective clothing and its testing method of quantity of electric charge are introduced, and the influence of temperature and relative humidity on the quantity of electric charge (qe) of static protective clothing is studied by measuring qe of different clothing samples. The result shows that temperature and relative humidity can influence qe of static protective clothing to some extent and the influence of relative humidity is bigger than that of temperature. According to experimental results, the relationship of qe and relative humidity and temperature was analysed, and the safety boundary of quantity of electric charge is discussed. In order to reduce the occurrence of electrostatic accidents and ensure safe production and operation of petrochemical industry, some suggestions on choosing and using of static protective clothing are given for guaranteeing its static protective performance.

In this paper, the influence of ambient temperature and relative air humidity on the hydrophobicity transfer property of HTV and RTV silicone rubber (SR) is investigated. The static contact angle on polluted HTV-SR samples and plates with RTV coating was measured while being stored at different temperature and relative humidity. It has been found that the transfer characteristics on HTV-SR exhibit a saltus between 50°C and 55°C. The results further show that the influence of relative humidity is related with the hygroscopicity of soluble and non-soluble substances in pollutants on the surface.

In this paper, the influence of ambient temperature and relative air humidity on the hydrophobicity transfer property of HTV and RTV silicone rubber (SR) is investigated. The static contact angle on polluted HTV-SR samples and plates with RTV coating was measured while being stored at different temperature and relative humidity. It has been found that the transfer characteristics on HTV-SR exhibit a saltus between 50°C and 55°C. The results further show that the influence of relative humidity is related with the hygroscopicity of soluble and non-soluble substances in pollutants on the surface.

Improved numerical model for steel reinforcement corrosion in concrete considering influences of temperature and relative humidity

The main feature of this article is the investigation on the influence of temperature, relative humidity, film thickness on permeability of PET packaging film, the analysis of perm-selectivity of the packaging films for oxygen gas and carbon dioxide gas, and the evaluation on experimental formulas of water vapor, O2 and CO2 gas permeating rates on the basis of gas molecular osmotic reaction kinetics and regression analysis. The comparison between experimental studies and calculation indicates that: (1) with increment of ambient temperature water vapor, O2 and CO2 permeating rate of PET films and PET/Al film also rise, and the logarithm of water vapor, O2 and CO2 gas permeating rates has linear relation with the reciprocal of thermodynamic temperature, and (2) the influence of relative humidity on water vapor permeating rate of PET film with thickness 12µm is the least, and that of PET film with thickness 20µm and PET/Al film with thickness 18µm is a little obvious. (3) The PET films hold remarkable perm-selectivity for O2 and CO2 gas, and CO2 gas permeating rate is about two times of O2 gas, yet O2 and CO2 gas permeating rates of PET/Al film are both very low and have small difference, so the PET/Al film has better barrier performance than the PET film.

The concentration of air pollutants in ambient air is governed by the meteorological parameters such as atmospheric wind speed, wind direction, relative humidity, and temperature. This study analyses the influence of temperature and relative humidity on ambient SO2, NOx, RSPM, and SPM concentrations at North Chennai, a coastal city in India, during monsoon, post-monsoon, summer, and pre-monsoon seasons for 2010-11 using regression analysis. The results of the study show that both SO2 and NOx were negatively correlated in summer (r2=0.25 for SO2 and r2=0.15 for NOx) and moderately and positively correlated (r2=0.32 for SO2 and r2=0.51 for NOx) during post-monsoon season with temperature. RSPM and SPM had positive correlation with temperature in all the seasons except post-monsoon one. These findings indicate that the influence of temperature on gaseous pollutant (SO2 & NOx) is much more effective in summer than other seasons, due to higher temperature range, but in case of particulate, the correlation was found contradictory. The very weak to moderate correlations existing between the temperature and ambient pollutant concentration during all seasons indicate the influence of inconstant thermal variation in the coastal region. Statistically significant negative correlations were found between humidity and particulates (RSPM and SPM) in all the four seasons, but level of correlation was found moderate only during monsoon (r2=0.51 and r2=0.41) in comparison with other three seasons and no significant correlation was found between humidity and SO2, NOx in all the seasons. It is suggested from this study that the influence of humidity is effective on subsiding particulates in the coastal region.

Mass concentrations of PM 10 and PM 2.5 are planned as new standards for the monitoring of ambient air quality in the European Union. Standard procedure is the removal of particles > 10 microns and > 2.5 microns aerodynamic diameter, respectively, by impaction in a preseparator. Different samplers work according to different principles of flow control. The influence of ambient temperature, pressure and relative humidity on different devices is calculated to estimate the comparability of various aerosol samplers. Therefore, the effects of these ambient factors on the volume flow as well as on the cut-off dp50 are investigated. In a second step, the influence of relative humidity on the flow control device is calculated. The results show that the cut-off shifts (up to 6.4%) for varying ambient conditions. Therefore, the influence on the impaction process should not be neglected and an 'ideal sampler' would measure temperature, pressure and relative humidity and adapt the volume flow to avoid a systematic error in the cut-off.

Vapor adsorption is an important process for the environmental fate of many organic pollutants by influencing the transport and degradation processes in the environment. This work is part of an attempt to understand vapor adsorption by systematically studying the influence of adsorbent, adsorbate, temperature, and relative humidity (RH) on the adsorption equilibrium. Here adsorption to three well-defined minerals (hematite, corundum, and lime) was studied by a chromatographic method. An exponential decrease of the adsorption coefficients of all tested compounds on all adsorbents was found between 30 and 90% RH. Below 30%, the influence of relative humidity was even stronger. The same functional relationship had been found for quartz and clay minerals tested earlier (1, 2). We therefore hypothesize that this relationship may be valid for all minerals in general. Differences in the surface area-normalized adsorption on different mineral surfaces were found, and they were most distinct at low relative humidities. These differences became smaller with increasing relative humidity and disappeared when humidity approached 100% RH. The extrapolated adsorption coefficients at 100% RH agree with those reported for a bulk water surface. At close to 100% RH, the adsorbed water film apparently was thick enough to prevent influence of the mineral surface on adsorption. The heats of adsorption did show a slight dependence on the mineral surface. As expected, they increased for adsorbents and compounds with increasing adsorption coefficients. Finally, the adsorption of organic vapors to a mixture of two minerals, Ca-kaolinite and corundum, was found to equal the linear sum of the contributions of the single minerals.

The influence of relative air humidity on the surface charge decay on epoxy resin insulators initially charged by DC corona and on their surface resistivity is investigated at room temperature. It has been observed, that surface resistivity of the epoxy resin insulators decreases significantly at higher relative humidity. Thus, at higher relative humidity surface charge decay is dominated by electric conduction along the insulator surface. This effect has been verified by both, measurement and simulation of the surface charge decay.

Abstract:Large seasonal variation in the rate of change in girth of tropical rain-forest tree species has been described, but its origin is still under debate. We tested whether this variation might be related to variation in atmospheric relative humidity through its influence on bark water content and thickness. Variation in trunk circumference of 182 adult trees was measured about twice a month in an undisturbed tropical rain forest over 18 mo using dendrometers. Furthermore, a laboratory experiment was conducted to test the direct influence of relative air humidity on bark water content and thickness. In the field, most trees displayed highly positive rates of change in girth at the onset of the wet season, while a quarter of the trees displayed negative changes during long dry seasons, whatever their total annual growth. This variation was correlated with environmental conditions, particularly with atmospheric relative humidity. Trees with high bark water content and thickness displayed a stronger decrease in girth during the dry season. In the chamber experiment, desiccation induced a decrease in the diameter of the trunk sections in tandem with a decrease in bark water content. As a result, seasonal variation in the rate of change in girth of tropical rain-forest trees reflects variation in trunk biophysical properties, through the influence of relative humidity on bark properties, but not directly variation in secondary growth.

A numerical study has been conducted to investigate the influence of fin pitch and relative humidity on the heat transfer performance of the fin-and-tube heat exchangers having plain fin geometry under dehumidifying conditions. The analysis is done using the ratio between the heat transfer coefficients in totally wet conditions and those in totally dry conditions using the appropriate correlations for both dry and wet conditions. For a constant relative humidity, it is found that the heat transfer coefficient increases with the increase of the air frontal velocity. By contrast, the fin efficiency decreases when the face velocity is increased. Apparently, this phenomenon is attributed to the path of condensate drainage. For the influence of relative humidity, the results showed an increase in heat transfer performance and a decrease in wet fin efficiency when relative humidity increases. This is due to the higher amount of mass transfer encountered at higher relative humidity. However, it is found that the effect of fin pitch on the heat transfer performance depends strongly on the face velocity. At lower frontal velocity the heat transfer increases with fin pitch. Conversely, an increase in fin pitch gives lower heat transfer coefficients when air velocity is increased.

Mould growth on building materials under low water activities. Influence of humidity and temperature on fungal growth and secondary metabolism

The twolined spittlebug, Prosapia bicincta (Say) (Hemiptera: Cercopidae), is an important insect pest of turfgrass in the eastern United States. Although twolined spittlebug infests most warm-season turfgrasses, the influence of low and high relative humidity (RH) on the expression of feeding damage in warm-season turfgrasses is not well understood. Experiments were conducted in which five warm-season turfgrasses were caged with ten twolined spittlebug adults and exposed to 40% and 95% RH for 5 days. The extent of damage was measured with a SPAD meter (chlorophyll content), and ratings of greenness, yellowness, and purpleness were obtained using a scale system. Physiological parameters such as stomatal conductance (GS), photosynthesis (A), evapotranspiration (E), and water use efficiency (WUE) were measured. Under both 40 and 95% RH, bermudagrass [Cynodon L.C. Rich, spp.] exhibited injury symptoms after twolined spittlebug exposure. The rate of A was lower in the presence of twolined spittlebug in bermudagrass under both RHs. Injury symptoms in centipedegrass [Eremochloa ophiuroides (Munro) Hack] were only observed under high-RH conditions, whereas in zoysiagrass [Zoysia matrella (L.) Merrill.] symptoms were only observed under low RH. Minimal levels of symptom expression were observed in St. Augustinegrass [Stenotaphrum secundatum (Walt.) Kuntze], and no feeding symptoms were observed in seashore paspalum [Paspalum vaginatum Sw.] under low RH. Overall, the presence of twolined spittlebug A was influenced by high RH, whereas WUE was affected by low RH in most of the turfgrass genotypes.

Current measurements in pressurized gases at high electric field are performed using electrodes with coaxial geometry. To identify the main mechanisms involved in “dark current” measured, the influences of electrode roughness, gas pressure, relative humidity and temperature have been investigated. The experimental results reveal that charge injection from the electrode constitute the main mechanism responsible for dark current. The latter is considerably modified when relative humidity RH is changed via the influence of pressure and temperature. The measured current shows an exponential increase versus electric field and also versus RH. It is thus assumed that water adsorbed on the electrodes induces an enhancement of charge injection from the electrode surface.

The influence of temperature, relative humidity, and storage time on the production of Ochratoxin A by the fungus Aspergillus niger in dry parchment coffee was determined under controlled laboratory conditions. Additionally, the roasting curve that would achieve maximum reduction of OTA concentration in roasted coffee was evaluated. The objective was to establish strategies to reduce the risk of product contamination by this mycotoxin in coffee farms and its presence in coffee ready for consumption. For the analysis of the influence of temperature, relative humidity, and storage times on OTA production, sterilized coffee samples incubated with the A. niger strain were used. To obtain the roasting curves, coffee samples stored for 15 days at a temperature of 23 °C and relative humidity of 60% were employed. The OTA concentration of each study samples was quantified by ultra-performance liquid chromatography coupled to tandem mass spectrometry (UPLC-MS/MS). The results obtained enabled: (1) The understanding of the conditions of temperature, relative humidity, and storage time that favor the production of the toxin by A. niger, thus allowing the development of coffee storage protocols that reduce grain contamination by this toxin, as it was found that increases in storage time and decreases in temperature and relative humidity to certain values are associated with increases in OTA concentration in the DPC. (2) Identifying the roasting curve whereby the coffee was subjected to temperatures from 180 °C to 208.8 °C for 11.23 min, achieving an OTA degradation of 76.4%. This curve serves as a guide for the adjustment of the temperatures and roasting times around the variables present in the process, achieving different roasting profiles, a significant reduction of OTA without affecting the quality of the coffee, and facilitating different chemical, physical, and organoleptic characteristics that can accommodate consumers’ tastes and ensure a safe beverage.