Systems and methods for delivering explosive mixtures with gas bubbles that are resistant to in-borehole migration or coalescence are disclosed herein. Such explosive can be sensitized by mechanically introducing gas bubbles into the explosive matrix in a number of gassing stages. Resistance to gas bubble migration and coalescence without the need for bubble stabilization agents can be achieved by homogenization in a number of homogenizing stages.

A high-shear mixing chamber is provided having a single wide slot microchannel that enables a higher throughput, less plugging, and a longer life (e.g., less wear) than typical multi-slotted mixing chambers. The provided mixing chamber may include an inlet and an outlet in fluid communication with a single wide slot microchannel (e.g., via an inlet and outlet plenum). In some aspects, the wide slot microchannel may have a stepped interior such that the wide slot microchannel has portions with different depths. The wide slot microchannel has a first surface opposite a second surface and one or more steps may be formed with the first surface alone, the second surface alone, or with both the first surface and the second surface. The steps may extend a full length of the microchannel between the inlet and outlet chambers.

An exhaust-gas treatment arrangement for an exhaust system of an internal-combustion engine includes a diesel internal-combustion engine. The arrangement includes a first exhaust-gas treatment unit and, downstream of the first exhaust-gas treatment unit, an exhaust-gas treatment assembly. The first exhaust-gas treatment unit and the exhaust-gas treatment assembly are arranged axially succeeding one another in the direction of a longitudinal axis of a flow path encompassing the first exhaust-gas treatment unit and the exhaust-gas treatment assembly. A hydrocarbon-feeding assembly is provided for feeding hydrocarbon into exhaust gas flowing in the flow path. The hydrocarbon-feeding assembly includes a hydrocarbon-dispensing unit dispensing hydrocarbon into the flow path downstream of the first exhaust-gas treatment unit and upstream of the exhaust-gas treatment assembly. A swirl-flow-generating unit is provided in the flow path upstream of the hydrocarbon-dispensing unit.

A mixer for fluid is described. The mixer comprises a housing. The housing comprises an inlet and an outlet, wherein the housing further comprises first and second portions, the first portion being of a substantially cylindrical internal shape of constant radius R.sub.1, and the second portion being of a substantially conical frustum internal shape of varying radius between R.sub.1 and R.sub.2, wherein R.sub.1<R.sub.2. A spindle is rigidly fixed within the housing, and comprises first and second portions, the first portion being of a substantially conical frustum shape of varying radius between r.sub.1 and r.sub.2, where r.sub.1<r.sub.2, and the second portion being of a substantially cylindrical shape of radius r.sub.2. At least part the first portion of the spindle is housed within the first portion of the housing, and at least part of the second portion of the spindle is housed within the second portion of the housing.

A multi-gap valve including: a fluid inlet and a fluid outlet; a cone having an inner channel developing along an axial direction and having through openings emerging in the inner channel, the inner channel being in fluid communication with the fluid inlet; a sleeve arranged coaxially and external to the cone; a plurality of gaps formed between the cone and the sleeve, the sleeve and said cone being axially adjustable relative to one another so as to vary the dimension of the gaps; an annular chamber obtained between the sleeve and an inner surface of the housing and being in fluid communication with the fluid outlet;
wherein the fluid inlet is axially aligned with the channel and the fluid outlet is misaligned with respect to the axial direction of said channel.

The invention relates to a coaxial flow device 1 capable of creating comparable microenvironments at various operation scales through the continuous introduction and mixing of nanoparticle precursor solutions for the manufacturing of a dispersion comprising nanoparticles. According to the invention, the device includes first and second coaxial tubes 3, 5 for controlled flows of nanoparticle precursor solutions and a mixing portion 7, wherein a disrupting physical element 21 is arranged to cause formation of the microenvironments. Application to the production of mRNA vaccines.