Pressure measurement is the measurement of an applied force by a fluid on a surface. Pressure is typically measured in units of force per unit of surface area. Many techniques have been developed for the measurement of pressure and vacuum. Instruments used to measure and display pressure mechanically are called pressure gauges,vacuum gauges or compound gauges. The widely used Bourdon gauge is a mechanical device, which both measures and indicates and is probably the best known type of gauge.
A pump is a device that moves fluids, or sometimes slurries, by mechanical action, typically converted from electrical energy into hydraulic energy.
Relative density, also called specific gravity, is a dimensionless quantity defined as the ratio of the density of a substance to the density of a given reference material. Specific gravity for liquids is nearly always measured with respect to water at its densest ; for gases, the reference is air at room temperature. The term "relative density" is preferred in SI, whereas the term "specific gravity" is gradually being abandoned.
A burette is a graduated glass tube with a tap at one end, for delivering known volumes of a liquid, especially in titrations. It is a long, graduated glass tube, with a stopcock at its lower end and a tapered capillary tube at the stopcock's outlet. The flow of liquid from the tube to the burette tip is controlled by the stopcock valve.
A pipette is a type of laboratory tool commonly used in chemistry and biology to transport a measured volume of liquid, often as a media dispenser. Pipettes come in several designs for various purposes with differing levels of accuracy and precision, from single piece glass pipettes to more complex adjustable or electronic pipettes. Many pipette types work by creating a partial vacuum above the liquid-holding chamber and selectively releasing this vacuum to draw up and dispense liquid. Measurement accuracy varies greatly depending on the instrument.
A rotary evaporator (rotavap) is a device used in chemical laboratories for the efficient and gentle removal of solvents from samples by evaporation. When referenced in the chemistry research literature, description of the use of this technique and equipment may include the phrase "rotary evaporator", though use is often rather signaled by other language.
A liquid handling robot is used to automate workflows in life science laboratories. It is a robot that dispenses a selected quantity of reagent, samples or other liquid to a designated container.
A metering pump moves a precise volume of liquid in a specified time period providing an accurate volumetric flow rate. Delivery of fluids in precise adjustable flow rates is sometimes called metering. The term "metering pump" is based on the application or use rather than the exact kind of pump used, although a couple types of pumps are far more suitable than most other types of pumps.
An eye dropper, also called Pasteur pipette or simply dropper, is a device used to transfer small quantities of liquids. They are used in the laboratory and also to dispense small amounts of liquid medicines. A very common use was to dispense eye drops into the eye. The commonly recognized form is a glass tube tapered to a narrow point and fitted with a rubber bulb at the top, although many styles of both plastic and glass droppers exist. The combination of the pipette and rubber bulb has also been referred to as a teat pipette. The Pasteur pipette name is from the French scientist Louis Pasteur, who used a variant of them extensively during his research. In the past, there was no equipment to transfer a chemical solution without exposing it to the external environment. The hygiene and purity of chemical compounds is necessary for the expected result of each experiment. The eye dropper, both glass and plastic types, can be sterilized and plugged with a rubber bulb at the open end of the pipette preventing any contamination from the atmosphere. Generally, they are considered cheap enough to be disposable, however, so long as the glass point is not chipped, the eye dropper may be washed and reused indefinitely.
Custody Transfer in the oil and gas industry refers to the transactions involving transporting physical substance from one operator to another. This includes the transferring of raw and refined petroleum between tanks and railway tank cars; onto ships, and other transactions. Custody transfer in fluid measurement is defined as a metering point (location) where the fluid is being measured for sale from one party to another. During custody transfer, accuracy is of great importance to both the company delivering the material and the eventual recipient, when transferring a material.
A gas meter prover is a device to verify the accuracy of a gas meter. Provers are typically used in gas meter repair facilities, municipal gas meter shops, and public works shops. Provers work by passing a known volume of air through a meter, while monitoring the gas meter's register, index, or internal displacement. The prover determines the meter factor, which is the volume of air passed divided by the volume of air measured.
A volumetric pipette, bulb pipette, or belly pipette allows extremely accurate measurement of the volume of a solution. It is calibrated to deliver accurately a fixed volume of liquid.
Reverse transfection is a technique for the transfer of genetic material into cells. As DNA is printed on a glass slide for the transfection process to occur before the addition of adherent cells, the order of addition of DNA and adherent cells is reverse that of conventional transfection. Hence, the word “reverse” is used.
Piston-driven air displacement pipettes are a type of micropipette, which are tools to handle volumes of liquid in the microliter scale. They are more commonly used in biology and biochemistry, and less commonly in chemistry; the equipment is susceptible to damage from many organic solvents.
A graduated pipette is a pipette with its volume, in increments, marked along the tube. It is used to accurately measure and transfer a volume of liquid from one container to another. It is made from plastic or glass tubes and has a tapered tip. Along the body of the tube are graduation markings indicating volume from the tip to that point. A small pipette allows for more precise measurement of fluids; a larger pipette can be used to measure volumes when the accuracy of the measurement is less critical. Accordingly, pipettes vary in volume, with most measuring between 0 and 25.0 millilitres.
Boom method is a solid phase extraction method for isolating nucleic acid from a biological sample. This method is characterized by "absorbing the nucleic acids (NA) to the silica beads".
Reverse pipetting is a technique to dispense a measured quantity of liquid by means of air displacement pipette. The technique is mainly recommended for solutions with a high viscosity or a tendency to foam: as it reduces the risk of splashing, foam or bubble formation. Reverse pipetting is more precise in dispensing small volumes of liquids containing proteins and biological solutions compared to forward pipetting, which is mostly used for aqueous solutions, such as buffers, diluted acids or alkalis.
A media dispenser or a culture media dispenser is a device for repeatedly delivering small fixed volumes of liquid such as a laboratory growth medium like molten agar or caustic or volatile solvents like toluene into a series of receptacles. It is often important that such dispensers operate without biological or chemical contamination, and so must be internally sealed from the environment and designed for easy cleaning and sterilization before use. At a minimum, a media dispenser consists of some kind of pump connected to a length of discharge tubing or a spout. Dispensers used in laboratories are also frequently connected to microcontrollers to regulate the speed and volume of the medium as it leaves the pump.
Heinrich Schnitger was a German physician. He is considered the inventor of the piston stroke Micropipette, a laboratory device for dispensing small amounts of liquid.
Positive displacement pipettes are a type of pipette that operates via piston-driven displacement. Unlike an air displacement pipette, which dispenses liquid using an air cushion in the pipette tip, the piston in a positive displacement pipette makes direct contact with the sample, allowing the aspiration force to remain constant.
