Thermodynamics

Thermodynamics States About Energy Conversion Thermodynamics is the branch of science that embodies the principles of energy transformation in macroscopic systems. The general restrictions which experience has shown to apply to all such transformations are known as the laws of thermodynamics. These laws are primitive; they cannot be derived from anything more basic. The first law of thermodynamics states that energy is conserved; that, although it can be altered in form and transferred from one place to another, the total quantity remains constant. Thus, the first law of thermodynamics depends on the concept of energy; but, conversely, energy is an essential thermodynamic function because it allows the first law to be formulated. This coupling is characteristic of the primitive concepts of thermodynamics. The words system and surroundings are similarly coupled. A system is taken to be any object, any quantity of matter, any region, and so on, selected for study and set apart (men

PH Meter

Many pH meter product have been offered from pH meter producers. For example Yokogawa products and parts are guaranteed to be free from defects in workmanship and materials under normal use and service for a period of (typically) 12 months from the date of shipment from the manufacturer.
Individual sales units may offer different warranty periods, so the original purchase order
should be consulted for the conditions of sale. Damage caused by normal wear and tear,
inadequate maintenance, corrosion, or due to chemical processes, is excluded from this
warranty coverage.
In the event of a warranty claim, any items that are considered to be defective should be
sent (freight paid) for repair or replacement (at Yokogawa discretion) to the service
department of the relevant sales unit. The following information must be included in a
letter accompanying the returned items:
  • Model code and serial number
  • Copy of original purchase order showing the date
  • Length of time used, and the measuring environment
  • Fault symptoms, and circumstances of failure
  • Statement whether service under warranty or out-of-warranty service is requested
  • Complete shipping and billing instructions for return of goods, plus the name and phone number of a contact person who can be reached for further information
  • Goods that have been in contact with process fluids must be decontaminated / disinfected before shipment, and a statement to this effect should be included. Safety data sheets for all process components that the goods have exposed to should also be included.
Misuse by the user:
  • Inappropriate or out-of-specifications use of the product;
  • Use in an unsuitable environment;
  • Repair or modification of this or related products by persons other than Yokogawaauthorized engineers.