Systems and methods for using microfluidic devices to concentrate cells, to perform buffer changes, to sort cells based on size, and/or to isolate particular types of cells in a rapid manner, are presented. Cells flow into a matrix of posts, wherein the posts are distributed along diagonal lines in the chamber. The cells are deflected in a lateral manner, towards a side of a chamber and are collected upon exiting the chamber.

A microfluidic device can include an upstream passage, a sample passage, a bifurcating passage, and a combining passage. The upstream passage can be configured to provide a focusing stream. The sample passage can be configured to provide a sample stream. The bifurcating passage can include a specified bifurcating flow resistance. The combining passage can be configured to create a combined stream from the focusing stream and the sample stream, where the focusing stream can direct the sample stream away from the upstream passage and toward the bifurcating passage. A first portion of the combined stream can be discharged through the bifurcating passage. The main discharge can be configured to discharge a second portion of the combined stream. The main discharge can include a main discharge resistance that is selectable to vary the main discharge resistance relative to the bifurcating flow resistance.

The present invention relates to apparatus for in real time detecting biological particles and non-biological particles in the atmosphere, the apparatus comprising: an impactor adapted to sort the biological particles and non-biological particles absorbed from the outside by size; a charger adapted to charge the biological particles and non-biological particles sorted by means of the impactor to specific charge (positive or negative charge); a separator adapted to introduce the biological particles and non-biological particles charged by the charger thereinto and to sort the biological particles and non-biological particles charged to different charge quantities from each other; and a particle measurement sensor adapted to measure the concentrations of the particles discharged from an outlet.

A process is disclosed for using multiple acoustic resonators to sample fluids (gas or liquids), capture particulate (or aerosols) entrained in the fluid, and deliver a concentrated sample of particulate. The acoustic concentrator demonstrates many improvements over prior art that includes improved concentration of particulate below 3 micron, adjustability of the level of concentration, ability to function over a wide range of humidity and temperature, and reduced overall power consumption. For example, when installed on the inlet of an aerosol detection system, the acoustic concentrator has been shown to increase sensitivity that may lead to earlier detection of bioaerosol agents.

A triaxial test apparatus for measuring eroded soil particles under action of seepage force includes a constant-flow seepage system, a soil particle transport grading measurement system, a large-range volume pressure control vacuum system and a data processing and analyzing system, where the constant-flow seepage system is connected to the soil particle transport grading measurement system and the large-range volume pressure control vacuum system by means of pipelines separately, the data processing and analyzing system includes a data acquisition device and a computer, the constant-flow seepage system, the soil particle transport grading measurement system and the large-range volume pressure control vacuum system are connected to the data acquisition device by means of lines separately, and the computer is connected to the data acquisition device by means of a line.

A fluid refining device comprises at least two obstructions adapted to be facing with a front in an upstream direction towards an incoming fluid and a base edge opposite of the front, and a fluid outlet arranged at the base edge.

Blood containing cells is brought into contact with a porous surface of a porous material before classification of the cells in the blood by flowing the blood through a microchannel. In an example, the porous material is added to the blood containing the cells and mixed together, thereby bringing the blood containing the cells into contact with the porous surface. In an example, the porous material has particles with the porous surface including polysaccharides. The porous material is added to the blood containing the cells while being suspended in a liquid. In an example, the particles have a predetermined particle size distribution. A median particle size d50V in the volume-based cumulative distribution is 25 to 280 μm.

An object of the present claimed invention is to improve cell cooling performance, keep a temperature of a dispersion medium constant, and improve measurement accuracy. The particle size distribution measuring device of this invention comprises a cell holding body 31 that holds a cell 2 housing a measurement sample and that is rotated by a motor 322, a case (C) having a housing space (S) for rotatably housing the cell holding body 31, and a cooling mechanism 8 for cooling the cell 2. The cooling mechanism 8 comprises a cooler 81, and a supply channel 82 that supplies a gas that has been cooled by the cooler 81 to the housing space (S).

A MEMS sensing device for sensing microparticles in an environment external to the MEMS sensing device is provided. The MEMS sensing device comprises a semiconductor body integrating a sensor and a pump unit, the sensor including a sensor cavity, a membrane suspended over the sensor cavity, and a piezoelectric element over the membrane and configured to cause the membrane to oscillate, about an equilibrium position, at a corresponding resonance frequency when sensing electric signals are applied to the piezoelectric element during a first operative phase of the MEMS sensing device, the resonance frequency depending on an amount of microparticles located on the membrane, the membrane having a plurality of through holes for establishing a fluid communication between the sensor cavity and the environment; the pump is configured to cause air pressure in the sensor cavity to be reduced with respect to the air pressure of the environment during the first operative phase, so that microparticles are caused to adhere onto the membrane by a suction force through the plurality of through holes.

The present invention relates to method of testing the bacterial filtering efficiency of a fabric, the method including the steps of preparing a solution including bacteria, peptone water and NaCl, feeding said solution including bacteria to a nebulizer, generating an aerosol of said bacterial solution and flowing said solution through a cascade impactor to provide a plurality of bacteria colonies in a plurality of plates present in a plurality of stages of said cascade impactor, characterized in that the concentration of NaCl in the peptone water used to prepare said bacterial solution is in the range of 30 g/L to 150 g/L and in that the temperature of said cascade impactor is in the range of −15° C. to 15° C.