Understanding Geologic Time and Unconformities
Geologic Time: An unconformity is a buried surface of erosion separating younger strata above from older strata below. Which of the following best characterizes an angular unconformity? Tilted strata lie below the unconformity; bedding in younger strata above is parallel to the unconformity. In the late 1700s, James Hutton published his important work titled Theory of the Earth. Which of the following is not a very long-lived radioactive isotope? C-14. Catastrophism was a philosophy that was first
Read MorePrintable Forms: Types, Manufacturing, and Preparation
Printable Forms and Offset Printing Processes
A printable form is an element placed on a printing machine that makes copies of an original graphic area. The image area retains ink, while the non-image area (contragrafismo) retains water and repels ink.
Planographic Printing Methods
Planographic printing is a method where the image and non-image areas are on the same level. Common examples include:
- Lithography: Uses oil-based ink directly. Historically, lithographic forms were made of stone, but now
Materials, Properties, and Applications: Wood & Metals
Materials and Raw Materials
Raw materials are resources obtained directly from nature without undergoing any transformation. The main ones are:
- Air: Used in chemical reactions, lens manufacturing, and fertilizer production.
- Water: Used in non-potable manufacturing, chemical reactions, lens production, and paper making.
- Rocks and Minerals: Used to produce metals, glass, etc.
- Petroleum: Used to obtain gasoline, diesel fuel, etc.
- Vegetables: Provide fibers, resins, pigments, etc.
- Animals: Used for silk, wool,
Solar Energy Systems: Collectors, Power Plants, and PV
Stationary Collectors
Flat-Plate Collectors (FPC)
Consist of the following components:
- Glazing: Diathermanous material.
- Tubes: To conduct the heat transfer fluid from the inlet to the outlet.
- Absorber plates: Flat plate to which the tubes are attached.
- Headers: To admit and discharge the fluid.
- Insulation: To minimize heat loss.
- Container: To surround the other components.
When solar radiation passes through the transparent cover, a portion of this energy is absorbed by the plate and transferred to the transport
Read MoreWood Defects: Juvenile Wood and Growth Stresses
Young Heart Wood
A defect that occurs in wood from trees that have had a strong initial growth rate in diameter, as a result of having found very favorable ecological conditions or growing up in a forest of low mass density (low density of trees per hectare or defective). This rapid growth results in wood different from normal wood for a particular species, with the following characteristics:
- In the late wood, there was a lower proportion of cells with thick walls.
- From the foregoing feature, the apparent
Energy, Heat, and Temperature: Understanding the Basics
Energy
Energy is a physical quantity that represents the capacity of bodies to cause transformations in themselves or in other bodies.
Types of Energy
- Mechanical Energy: Possessed by bodies in motion (kinetic energy), those at a certain height (potential energy), or those that have experienced deformation (elastic energy).
- Electrical Energy: Possessed by electric current.
- Nuclear Energy: Produced in nuclear reactions of fusion and fission.
- Thermal Energy: Energy that flows from one body to another when