Abstract: A method is disclosed for controlling the growth of undesired vegetation in a plantation crop by applying to the locus of the crop an effective amount of a compound of formula I ##STR1## and A, R.sup.1, R.sup.2, R.sup.3, R.sup.4, X, Y and Z are as defined in the disclosure. Also disclosed are novel substituted heterocyclic compounds and their agriculturally suitable compositions which are generally useful as herbicides, as well as methods of their use as general or selective preemergent or postemergent herbicides, or as plant growth regulants.

Abstract: This invention provides herbicides for use in plantation and specialty crops; and further provides novel substituted heterocyclic compounds, their agriculturally suitable compositions, and methods of using these compounds as preemergent or postemergent herbicides.

Abstract: Disclosed is a cooling device of a microwave oven which can be easily assembled on a rear wall of a microwave oven with reduced noise, improved cooling efficiency, and increased space efficiency of a machine chamber thereof. The cooling device has a fan cover disposed on the rear wall and having a plurality of pores formed therein. Side panels of the fan cover extend inward with such an inclination that the inner surfaces of the side panels confront a cooling fan. The fan cover protrudes backward from the machine chamber, and has a dent replacing a separate spacer for ensuring the introduction of air through the pores regardless of the place at which the microwave oven is installed.

Abstract: Disclosed is a microwave power controlling device having a reduced production cost and an improved assembling work efficiency by using a simple structure and the reduced number of components. A supporting stepped portion is formed on an inner surface portion of a control panel having a rotating through hole formed at a central portion thereof into which a knob axis for controlling the microwave power is inserted. An elastic piece and a pair of stoppers are formed on an upper surface of the supporting stepped portion. On an opposite surface of the supporting stepped portion, a microwave power controlling gear is mounted. The microwave power controlling gear has an engaging jaw for defining a rotating range thereof and a ring-shaped guide portion having plural notched grooves engaged with the elastic piece. The microwave power controlling gear is meshed with a coupling gear meshed with a microwave power controlling circuit gear of a timer body.

Abstract: A noise shielding apparatus for the magnetron of a microwave oven for preventing the lowering of the voltage resistance of the capacitor due to the poor concentricity and the poor interfacial state is disclosed. A shielding case has a side wall with an elliptic opening and a projected portion along the elliptic opening by bending out a circumference portion thereof. The capacitor includes an elliptic cylindrical ceramic dielectric, separate electrodes separately formed on an upper surface of the ceramic dielectric and a common electrode formed on a lower surface of the ceramic dielectric. Through conductors pass through the through holes and are connected to a choke coil of the magnetron. Each of through conductors is provided with an electrode connection portion for electrically connecting with the separate electrodes integrally and horizontally formed from around an upper portion of each of through conductors.