Abstract: An example assembly includes: a valve body having a cavity therein, wherein the valve body comprises internal threads formed in a first-handed direction and an external feature; a knob having an internal feature configured to engage with the external feature of the valve body to allow the internal feature of the knob to move past the external feature of the valve body in a linear direction when assembling the knob on the valve body; and a needle disposed in the cavity of the valve body and having external threads formed in the first-handed direction and engaging with the internal threads of the valve body, the needle being coupled to the knob such that rotation of the knob and the needle results in linear movement of the needle within the valve body due to engagement of the external threads of the needle with the internal threads of the valve body.

Abstract: An example assembly includes: a valve body having a cavity therein, wherein the valve body comprises internal threads formed in a first-handed direction and an external feature; a knob having an internal feature configured to engage with the external feature of the valve body to allow the internal feature of the knob to move past the external feature of the valve body in a linear direction when assembling the knob on the valve body; and a needle disposed in the cavity of the valve body and having external threads formed in the first-handed direction and engaging with the internal threads of the valve body, the needle being coupled to the knob such that rotation of the knob and the needle results in linear movement of the needle within the valve body due to engagement of the external threads of the needle with the internal threads of the valve body.

Abstract: An apparatus for multiple, simultaneous synthesis of compounds which consists of: a reservoir block having a plurality of wells; a plurality of reaction tubes, usually gas dispersion tubes, having filters on their lower ends; a holder block, having a plurality of apertures; and a manifold, which may have ports to allow introduction/maintenance of a controlled environment. The manifold top wall has apertures and a detachable plate with identical apertures. The apparatus is constructed from materials which will accommodate heating, cooling, agitation, or corrosive reagents. Gaskets are placed between the components. Rods or clamps are provided for fastening the components together. Apparatus operation involves placing the filters on the lower ends of the reaction tubes in the reservoir block wells, and the upper ends passing through the holder block apertures and into the manifold.

Abstract: A stirring system for stirring contents in a laboratory flask having a round or spherical bottom and a reduced neck includes a stirrer shaft manufactured with a ring at the lower end thereof which permits attachment of a blade with a nut and bolt made of TEFLON material. The nut and bolt prevents the stirrer blade from flipping over during assembly and allows for a controlled tightening force to be applied to ensure that the blade remains in proper stirring position during use. The nut and bolt design permits use of the shaft with any stirrer blade having a keyhole cutout or circular opening. A method of stirring contents in a laboratory flask by attachment of the stirrer blade to the stirrer shaft with a nut and bolt is also disclosed.