Humidity determination

Colburn equation, flat plates 434 Colorimetric methcxls for humidity determination 759 Comings, E. W, 745, 786 Compact heat exchangers 550 Compressed air for pumping 358 Compressibility factor 34, 35,161 Compressible fluids 30, 48... 

Hygrornetry see humidity determination Hysteresis loop, thixotropic and rhcopcotic fluids 114 Hvtor pumps 846... 

PsychrorneLry sec humidity determination Pugh. F. J, 205,228 PumiM. 1. 209, 228 Pulverised fuel particles 47 ... 

Sensor-based methods. Whilst many methods use sensors, the simplest being temperature measurement, this terminology is often used to cover viscosity, pH, oxygen and humidity determination, etc. These are true in-line techniques and offer rapid, inexpensive real-time analysis. Humidity determination in drying ovens is a common example. 

Acetone H3CC(0)CH3 UV-C, UV-B -[Substrate] effect of humidity determination of 0 Aloisio and Francisco (2000)... 

The outlet temperature and humidity determined in this manner are represented by a point on the psychrometric chart. If a lower value of Ts is assumed, a higher outlet humidity would be calculated, yielding another point on the chart. The set of ail such points for a specified and m i th defines a curve on the chart, known as the adiabatic saturation curve. If the three stated assumptions are valid, the final state of air undergoing an adiabatic humidification must lie on the adiabatic saturation curve that passes through the inlet state on the psychrometric chart. 

The Indoor conditions are 20°C and 60 percent relative humidity while the outside conditions are -15"C and 70 percent relative humidity. Determine if condensation or freezing of moisture will occur in the insulation. 

During a hot summer day, a canned drink is to be cooled by wrapping it in a cloth that is kept wet continually, and blowing air to it by a fan (Fig. 14-53). If the environment conditions are 1 aim, 30°C, and 40 percent relative humidity, determine the temperature of the drink when steady conditions arc reached. 

Consider a 5-m X 5-m wet concrete patio with an average water film thickness of 0.3 mm. Now wind at 50 km/h is blowing over the surface. If the air is at 1 atm, t5°C, and 35 percent relative humidity, determine how long it will take for the. patio to dry completely. Answer 18.6 min... 

Jugs made of porous clay were commonly used to cool water in the past. A small amount of water that leaks out keeps the outer surface of the jug wet at all times, and hot and relatively dry air flowing over the jug causes this water to evaporate. Part of the latent heat of evaporation comes from the water in the jug, and the water is cooled as a result. If the euvironment conditions are 1 atm, 30°C, and 35 percent relative humidity, determine the tcmpeiacure of the water when steady conditions are reached. 

Consider a SO-cm-diametcr pan filled with water at 15°C in a room at 20°C, 1 atm, and 30 percent relative humidity. Determine (a) the rale of heat transfer by convection, (ii) the rate of evaporaiion of water, and (c) the rate of heat transfer to the water needed to maintain its temperature at 15°C. Disregard any radiation effects. 

The biocatalyst mass obtained was 90.01 g, with 23% humidity, determined by the Karl Fischer automated titration model D18, Mettler. 

Figure 18.1 is a comparison of the simple M approximation and more refined phase-transition models. The mixing is assumed to be adiabatic and the release conditions correspond to the most humid case of the FLADIS ammonia field experiments (Nielsen et al., 1997 Nielsen and Ott, 1996). Wheatley s model (solid line) is the most accurate one since this includes the hygroscopic effect of ammonia. This solution may he divided into three domains dry mixing, nearly pure-water aerosols, and nearly pure ammonia aerosols. Experimentation with the model input reveals that atmospheric moisture affects the aerosol formation in two ways the relative humidity determines the limit of transition between the... 

Humidity is one of important environmental parameters, which refers to the water vapror content in the air. As one of the fundamental abiotic factors, humidity determines an environment where animals and plants can thrive, also influences the human life. There are three items commonly used to describe humidity, which are absolute humidity (AH), relative humidity (RH) and specific humidity (SH) [33]. In daily life and industrial measurement fields, relative humidity is one of the important and most commonly used parameters. 

Tricalcium phosphate (TCP) has a Ca P ratio of 1.5, similar to the amorphous biologic precursors of bone [5]. It can be prepared by sintering Ca deficient apatite (Ca P ratio 1.5). TCP is a polymorph ceramic and exhibits two phases (a- and -whitlockite), known as a- and (S-TCP. Variation in sintering temperature and humidity determine, which phase is being formed a-TCP occurs at dry heat >1300°C and subsequent quenching in water [4]. Solubility and resorbability of both forms is much higher compared to HA. However, a-TCP is unstable in water and reacts to produce HA. a-TCP is used mainly as a compound... 

When a coated system is exposed to an aqueous solution or a humid atmosphere, water molecules eventually reach the coating substrate interface. Normally, a coating under immersion will be saturated after a relatively short time (of the order of 1 h), depending on the values for D and S and the thickness of the layer. T5q)ically values for D and S are 10 m s and 3% [7-9]. For atmospheric exposure the actual cyclic behavior of ihe temperature and the humidity determines largely the periods of saturation. In any case, situations will result in which water molecules reach the coating-metal interface, where they can interfere with the bonding between the two phases, eventually resulting in loss of adhesion and corrosion initiation if a... 

Dew point This is the temperature at which a vapor-gas mixture becomes saturated when cooled at constant total pressure out of contact with a liquid. For example, if an unsaturated mixture such as that at F (Fig. 7,4) is cooled at constant pressure out of con,tact with liquid, the path of the cooling process follows the line FG, the mixture becoming more nearly saturated as the temperature is lowered, and fully saturated at the dew-point temperature. All mixtures of absolute humidity Y on this figure have the same dew point. If the temperature is reduced only an infinitesimal amount below t p, vapor will condense as a liquid dew. This is used as a method of humidity determination a... 

Since the samples are very hygroscopic, humidity determination has to be performed in parallel to elemental analyses. For that purpose, samples are equilibrated at room ambient conditions in Petri dishes for several hours just before use. Aliquots of 0.5 to 1 g are weighted and dried for 24 h at 100°C to determine the humidity content (/moisture) in triplicate. The CHN content obtained from the analyzer for each element k (/j.hum) are corrected for humidity content as follows to obtain the mass fraction of the element on dry weight. 

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