Powder in the context of Coal dust

A pipe is a tubular section or hollow cylinder, usually but not necessarily of circular cross-section, used mainly to convey substances which can flow — liquids and gases (fluids), slurries, powders and masses of small solids. It can also be used for structural applications; a hollow pipe is far stiffer per unit weight than the solid members.

In common usage the words pipe and tube are usually interchangeable, but in industry and engineering, the terms are uniquely defined. Depending on the applicable standard to which it is manufactured, pipe is generally specified by a nominal diameter with a constant outside diameter (OD) and a schedule that defines the thickness. Tube is most often specified by the OD and wall thickness, but may be specified by any two of OD, inside diameter (ID), and wall thickness. Pipe is generally manufactured to one of several international and national industrial standards. While similar standards exist for specific industry application tubing, tube is often made to custom sizes and a broader range of diameters and tolerances. Many industrial and government standards exist for the production of pipe and tubing. The term "tube" is also commonly applied to non-cylindrical sections, i.e., square or rectangular tubing. In general, "pipe" is the more common term in most of the world, whereas "tube" is more widely used in the United States.

In physics, a free surface is the surface of a fluid that is subject to zero parallel shear stress,such as the interface between two homogeneous fluids.An example of two such homogeneous fluids would be a body of water (liquid) and the air in the Earth's atmosphere (gas mixture). Unlike liquids, gases cannot form a free surface on their own.Fluidized/liquified solids, including slurries, granular materials, and powders may form a free surface.

A liquid in a gravitational field will form a free surface if unconfined from above.Under mechanical equilibrium this free surface must be perpendicular to the forces acting on the liquid; if not there would be a force along the surface, and the liquid would flow in that direction. Thus, on the surface of the Earth, all free surfaces of liquids are horizontal unless disturbed (except near solids dipping into them, where surface tension distorts the surface in a region called the meniscus).

Flour is a powder used to make many different foods, including baked goods, as well as thickening dishes. It is made by grinding grains, beans, nuts, seeds, roots, or vegetables using a mill.

Cereal flour, particularly wheat flour, is the main ingredient of bread, which is a staple food for many cultures. Archaeologists have found evidence of humans making cereal flour over 14,000 years ago. Other cereal flours include corn flour, which has been important in Mesoamerican cuisine since ancient times and remains a staple in the Americas, while rye flour is a constituent of bread in both Central Europe and Northern Europe. Cereal flour consists either of the endosperm, germ, and bran together, known as whole-grain flour, or of the endosperm alone, which is known as refined flour. 'Meal' is technically differentiable from flour as having slightly coarser particle size, known as degree of comminution. However, the word 'meal' is synonymous with 'flour' in some parts of the world. The processing of cereal flour to produce white flour, where the outer layers are removed, means nutrients are lost. Such flour, and the breads made from them, may be fortified by adding nutrients. As of 2016, it is a legal requirement in 86 countries to fortify wheat flour.

Granulation is the process of forming grains or granules from a powdery or solid substance, producing a granular material. It is applied in several technological processes in the chemical and pharmaceutical industries. Typically, granulation involves agglomeration of fine particles into larger granules, typically of size range between 0.2 and 4.0 mm depending on their subsequent use. Less commonly, it involves shredding or grinding solid material into finer granules or pellets.

A mortar and pestle is a set of two simple tools used to prepare ingredients or substances by crushing and grinding them into a fine paste or powder in the kitchen, laboratory, and pharmacy. The mortar (/ˈmɔːrtər/) is characteristically a bowl, typically made of hardwood, metal, ceramic, or hard stone such as granite. The pestle (/ˈpɛsəl/, also US: /ˈpɛstəl/) is a blunt, club-shaped object. The substance to be ground, which may be wet or dry, is placed in the mortar where the pestle is pounded, pressed, or rotated into the substance until the desired texture is achieved.

Mortars and pestles have been used in cooking since the Stone Age; today they are typically associated with the pharmacy profession due to their historical use in preparing medicines. They are used in chemistry settings for pulverizing small amounts of chemicals; in arts and cosmetics for pulverizing pigments, binders, and other substances; in ceramics for making grog; in masonry and other types of construction requiring pulverized materials. In cooking, they are typically used to crush spices, to make pesto, and certain cocktails such as the mojito, which requires the gentle crushing of sugar, ice, and mint leaves in the glass with a pestle.

Powder coating is a type of coating that is applied as a free-flowing, dry powder. Unlike conventional liquid paint, which is delivered via an evaporating solvent, powder coating is typically applied electrostatically and then cured under heat or with ultraviolet light. The powder may be a thermoplastic or a thermosetting polymer. It is usually used to create a thick, tough finish that is more durable than conventional paint. Powder coating is mainly used for coating of metal objects, particularly those subject to rough use. Advancements in powder coating technology like UV-curable powder coatings allow for other materials such as plastics, composites, carbon fiber, medium-density fibreboard (MDF), and solid wood to be powder coated, as little heat or oven dwell time is required to process them.

In granulometry, the particle-size distribution (PSD) of a powder, or granular material, or particles dispersed in fluid, is a list of values or a mathematical function that defines the relative amount, typically by mass, of particles present according to size. Significant energy is usually required to disintegrate soil, etc. particles into the PSD that is then called a grain size distribution.

Mare milk is milk lactated by female horses, known as mares, to feed their foals. It is rich in whey protein, polyunsaturated fatty acids and vitamin C, and is a key ingredient in kumis. In several European countries, including Germany, it is sold powdered.

Mare milk is sometimes chosen over cow milk for its purported health benefits. A niche market considers it a remedy for skin or digestive problems. Peer-reviewed papers suggest it can reduce atopic dermatitis or eczema. It is used to make cosmetics and can form cheese with camel rennet, but not bovine.

Laundry detergent is a type of detergent (cleaning agent) used for cleaning dirty laundry (clothes). Laundry detergent is manufactured in powder (washing powder) and liquid form.

While powdered and liquid detergents hold roughly equal share of the worldwide laundry detergent market in terms of value, powdered detergents are sold twice as much compared to liquids in terms of volume.

Metal powder is a metal that has been broken down into a powder form. Metals that can be found in powder form include aluminium powder, nickel powder, iron powder and many more. There are four different ways metals can be broken down into this powder form:

• Direct reduction
• Gas atomization
• Ultrasonic atomization
• Liquid atomization
• Centrifugal atomization