An air-water mixture is found from the heat and mass balance to be at 60°C (333 K) and 0.025 kg/kg (25 g/kg) absolute humidity. Calculate the other main parameters for the mixture. Take atmospheric pressure as 101,325 Pa.
Method: Consult item (vi) in Table 12-5 for the calculation methodology.
From the initial terminology section, specific humidity YW = 0.02439 kg/kg, mole ratio z = 0.0402 kmol/kmol, mole fraction y = 0.
Effect greenhouse What are greenhouse gases (GHG)? Greenhouse gases (GHGs) trap heat within the earth’s atmosphere, contributing to the ‘greenhouse’ effect and causing global warming. These gases include carbon dioxide, methane, nitrous oxide, and water vapor. Industry, including manufacturing, is the second largest global emitter of human-created GHGs. Much of industrial GHG emissions are due to the burning of fossil fuels for heat and power generation.
Why should I care about GHGs?
Structural steel grades are referred to by their corresponding ASTM designation. For example, the most commonly used grade of structural steel is A36, which is produced to meet the requirements of the ASTM A36 specification. This grade offers a good mix of strength, weldability, and cost. In many designs, this specification alone will satisfy designers’ needs. Other specifications, such as A53 for pipe, provide an equivalent grade of steel for that type of product.
Buildings should be designed to withstand minor earthquakes without damage, because they may occur almost everywhere. For major earthquakes, it may not be economical to prevent all damage but collapse should be precluded. Because an earthquake and a high wind are not likely to occur simultaneously, building codes usually do not require that buildings be designed for a combination of large seismic and wind loads. Thus, designers may assume that the full strength of wind bracing is also available to resist drift caused by earthquakes.
Introduction to geotextiles Although skins, brushwood, and straw–mud composites have been used to improve the soft ground for many thousands of years, it is not realistic to refer to these as ‘geotextiles’. The important factor that separates them from modern geotextiles is that they cannot be made with specific and consistent properties. When modern polymers were developed in the mid 20th century, it became possible to create textiles with designed forecastable performance and to produce them in large quantities with statistically consistent and repeatable properties.
When modern industrialization started in the 19th century, many people migrated from the agricultural area to the big cities. Public hygiene became a major problem. Human excrement and waste was discharged into open channels, rivers, and lakes. The pollution was disastrous and hygiene-related epidemic diseases, like cholera and typhus, occurred frequently. Therefore, it was an important step forward when public water collection systems and treatment plants were introduced at the end of the 19th century.
Automatic fire sprinkler systems have been protecting property in the United States since the late 1800s; in fact, the Standard for the Installation of Sprinkler Systems, 1896 was the first standard developed by the National Fire Protection Association (NFPA). Today the NFPA still develops the most widely accepted standards for the design and installation of sprinkler systems: NFPA 13, Standard for the Installation of Sprinkler Systems; 20, Installation of Centrifugal Fire Pumps; 24, Installation of Private Fire Services Mains and Their Appurtenances; 231, General Storage and 231C, Rack Storage of Materials.
What is a sustainable building? For your building to be sustainable, many factors need to be considered. These include air quality, energy
efficiency, and the use of ‘green’ materials among others. This document focuses on 1) building a sustainable building 2) retrofitting and 3) certification.
Why should I make my buildings sustainable? Apart from the environmental benefits, a sustainable building can reduce your operational costs by as much as 30-50% on your energy usage and 40-50% on your water usage.
This article will help you understand and become familiar with other sensors that play a very important part in process control, but may not be encountered on a daily basis. The following are covered in this article:
■ Position, distance, velocity, and acceleration sensors
■ Rotation sensors using light and Hall effect sensors
■ Force, torque, load cells, and balances
■ Smoke detectors, gas, and chemical sensors in the industry