An electrochemical hydrogen pump includes an electrolyte membrane, an anode on a first primary surface of the electrolyte membrane, a cathode on a second primary surface of the electrolyte membrane, and an anode separator on the anode. The anode includes an anode catalyst layer on the first primary surface of the electrolyte membrane and an anode gas diffusion layer on the anode catalyst layer. The anode gas diffusion layer includes a porous carbon sheet that is a powder molded body.

The devices and systems described herein generally relate to programmable surfaces. A set of tiles in conjunction with actuators, allow for the surface to be constantly changeable from a first shape to an unlimited variety of second shapes. Once a desired second shape is achieved, the shape can be held by actuating the actuators. The system can include detection and maintenance of the shapes of the programmable surface by controlling which of the actuators are released and when they are released.

Disclosed are devices, systems, apparatuses, methods, products, and other implementations of vapor pressure solids. In some embodiments, a vapor pressure solid may include a one- or multi-component matrix material. In some embodiments, the multi-components matrix material is a two-part PDMS comprising a first and second matrix material. The first matrix material is capable of being mixed with one or more vaporizable fluids that causes the first matrix material to swell. The second matrix material is capable of being mixed with the swelled first matrix material to produce an actuating material. When the actuating material is heated, the one or more vaporizable fluids expand, resulting in vapors. The increased pressure applied by the vapors causes the actuating material to expand.

The disclosure relates to an actuator based on carbon nanotubes and actuating system using the same. The actuator includes: a carbon nanotube layer and a vanadium dioxide layer stacked with each other. Because the drastic, reversible phase transition of VO.sub.2, the actuator has giant deformation amplitude and fast response. An actuating system using the actuator is also provided.

An artificial muscle device includes a plurality of intermuscular boards and a plurality of artificial muscles disposed between the intermuscular boards in an alternating pattern and communicatively coupled to a controller. Each of the one or more artificial muscles includes a housing comprising an electrode region and an expandable fluid region, a dielectric fluid housed within the housing, and an electrode pair positioned in the electrode region of the housing, the electrode pair including a first electrode and a second electrode. The electrode pair is actuatable between a non-actuated state and an actuated state such that actuation from the non-actuated state to the actuated state directs the dielectric fluid into the expandable fluid region, expanding the expandable fluid region, thereby applying pressure to the intermuscular boards.

An anode current collector of an electrochemical compressor includes a plurality of first portions and a plurality of second portions that are alternately arranged from the first end portion toward an inner side in a plane direction of the anode current collector. In the first portion, a first porous body, a second porous body, and a third porous body are sequentially stacked. In the second portion, the first portion, the third porous body, and the second porous body are sequentially stacked. The porosity of the second porous body is larger than the porosity of the first porous body and the porosity of the third porous body is larger than the porosity of the second porous body.

Systems and processes for purifying and concentrating a liquid feed stream are disclosed. In the systems, the concentrated liquid output from the high pressure side of a reverse osmosis stage is used as the draw solution in the low pressure side of the reverse osmosis stage in a configuration called osmotically assisted reverse osmosis. This reduces the osmotic pressure differential across the membrane, permitting high solute concentrations to be obtained, hastening the purification of the liquid. Reduced system pressures are also obtained by arranging multiple osmotically assisted reverse osmosis stages in a cross-current arrangement. Overall system energy consumption is reduced compared to conventional thermal processes for high concentration streams.

The disclosure relates to a method for making an actuator based on carbon nanotubes. The method includes: providing a carbon nanotube layer; depositing a vanadium oxide (VO.sub.x) layer on the carbon nanotube layer; and annealing the VO.sub.x layer in an oxygen atmosphere to form a vanadium dioxide layer (VO.sub.2) layer. Because the drastic reversible phase transition of VO.sub.2, the actuator has giant deformation amplitude and fast response.

Systems and processes for purifying and concentrating a liquid feed stream are disclosed. In the systems, the concentrated liquid output from the high pressure side of a reverse osmosis stage is used as the draw solution in the low pressure side of the reverse osmosis stage in a configuration called osmotically assisted reverse osmosis. This reduces the osmotic pressure differential across the membrane, permitting high solute concentrations to be obtained, hastening the purification of the liquid. Reduced system pressures are also obtained by arranging multiple osmotically assisted reverse osmosis stages in a cross-current arrangement. Overall system energy consumption is reduced compared to conventional thermal processes for high concentration streams.

Systems and processes for purifying and concentrating a liquid feed stream are disclosed. In the systems, the concentrated liquid output from the high pressure side of a reverse osmosis stage is used as the draw solution in the low pressure side of the reverse osmosis stage in a configuration called osmotically assisted reverse osmosis. This reduces the osmotic pressure differential across the membrane, permitting high solute concentrations to be obtained, hastening the purification of the liquid. Reduced system pressures are also obtained by arranging multiple osmotically assisted reverse osmosis stages in a cross-current arrangement. Overall system energy consumption is reduced compared to conventional thermal processes for high concentration streams.