Abstract: The present invention provides a pretreatment method which enables the promotion of the enzymatic glycosylation of lignocellulose under relatively mild conditions by using a tree bark as a raw material with less energy. Specifically the present invention provides a step for producing a sugar from a tree bark, which is characterized by having the following steps: an alkali treatment step of immersing the tree bark in an alkali compound solution; a refining treatment step of refining the alkali treated tree bark mechanically into fine pieces; and an enzymatic glycosylation step of glycosylating the refined tree bark with an enzyme. The present invention also provides a method of producing an ethanol.

Abstract: In an exhaust passage, a pressure detection means is provided on the upstream side of a filter, and an exhaust throttle valve is provided on the downstream side of the filter. And, when the operational state of the internal combustion engine is a steady operational state (in a step S101), the opening amount of an exhaust throttle valve is controlled so that the upstream pressure detected by the pressure detection means becomes a constant value (in a step S103).