Lee H.-Y.,University of Maryland University College |
Diehn K.K.,University of Maryland University College |
Sun K.,University of Maryland University College |
Chen T.,TA Instruments Waters LLC |
Raghavan S.R.,University of Maryland University College
Journal of the American Chemical Society | Year: 2011
We describe a new class of photorheological (PR) fluids whose rheological properties can be reversibly tuned by light. The fluids were obtained by doping lecithin/sodium deoxycholate (SDC) reverse micelles with a photochromic spiropyran (SP) compound. Initially, the lecithin/SDC/SP mixtures formed highly viscoelastic fluids, reflecting the presence of long, wormlike reverse micelles. Under UV irradiation, the SP was isomerized to the open merocyanine (MC) form, causing the fluid viscosity to decrease 10-fold. When the UV irradiation was switched off, the MC reverted to the SP form, and the viscosity recovered its initial value. This cycle could be repeated several times without loss of response. The rheological transitions are believed to reflect changes in the lengths of the reverse worms. To our knowledge, this is the first example of a simple, reversible PR fluid that can be made entirely from commercially available components. © 2011 American Chemical Society.
TA Instruments Waters L.L.C. | Date: 2016-06-02
In a mechanical test system, a method of compensating for acceleration induced load error in a load sensor in a mechanical communication with a component comprises measuring an acceleration of the component to obtain an acceleration measurement. A load sensor measures a force applied by the mechanical test system to a test sample in substantially a same direction of the acceleration to obtain a force measurement. The force measurement is modified with a transfer function that includes at least one of a gain correction and a phase correction to compensate for an error value in the force measurement attributed to movement of at least the load sensor when the force is applied to the test sample.
TA Instruments Waters L.L.C. | Date: 2015-09-17
This document provides fluid handling components. For example, this document relates to taper interface connections such as, but not limited to, luer taper interface connections used to couple fluid handling components in a medical or laboratory setting. In some embodiments, the threaded connection on the male portion of the taper interface is comprised of one or two opposing tabs, rather than a 360 collar like conventional luer lock fittings. As such, the taper interface components provided herein are readily manufacturable with a lower cost than conventional fittings that have a collar. In some embodiments, the taper interface components provided herein are configured for coupling by way of a quick connection technique.
TA Instruments Waters L.L.C. | Date: 2016-05-20
Systems, methods, and devices are provided for testing a drug eluting prosthesis. A drug eluting prosthesis is placed within a conduit that is coupled at one end to a first conduit frame and at a second end to a second conduit frame. The first conduit frame is coupled to the second conduit frame using a movable shaft, such that the first conduit frame and the second conduit frame can move relative to each other. When the first conduit frame and the second conduit frame are moved relative to each other, they expose the conduit and the drug eluting prosthesis to compressive or tensile forces. While the drug eluting prosthesis is being exposed to compressive or tensile forces, a fluid flow is provided through the conduit to test the particle shed rate of the drug eluting prosthesis.
Ta Instruments Waters L.L.C. | Date: 2014-06-17
This document provides systems and methods for testing of various kinds of valves. For example, this document provides systems and methods for accelerated life testing of prosthetic heart valves.
Ta Instruments Waters L.L.C. | Date: 2015-03-10
A chamber assembly for testing a valve includes a proximal chamber portion that defines a proximal interior space, and a distal chamber portion that defines a distal interior space. The distal interior space includes a gas space. When a liquid is inserted into the proximal and distal chambers there is an interface between the liquid and a gas in the gas space. A valve holder is disposed adjacent to the proximal interior space and the distal interior space. The valve holder is configured to receive the valve in a bore of the valve holder. A shortest distance between a center of the valve when in the bore and the interface is at least about 45 mm.
Ta Instruments Waters L.L.C. | Date: 2014-05-14
A bioreactor system includes a sample chamber capable of receiving a specimen and a cover which can be placed on the chamber to enclose the specimen within the chamber. A first member is movable between (i) a closed position in which the member restricts the cover from being moved away from the chamber in a first direction, and (ii) an open position in which the member does not restrict the cover from being moved away from the chamber. When the first member is in the closed position there is a substantially liquid proof seal between the cover and the chamber.
TA Instruments Waters L.L.C. | Date: 2015-11-20
An apparatus for fatigue testing an article includes a base having a platform for receiving an article to be tested, a shaft extending toward said platform for applying a force to said article, a coupling assembly connected to said shaft, said coupling assembly comprising a joint that pivots about an axis, and flex pivots disposed to be aligned with said axis about which said joint pivots.
Ta Instruments Waters L.L.C. | Date: 2014-07-31
A mechanical clamping device can include at least two contact faces, a first of the contact faces configured to travel in response to an applied force, each contact face configured to contact a sample when loaded into the mechanical clamping device. The device can further include a load element configured to cause the two contact faces to apply a clamping force to the sample when loaded into the mechanical clamping device.
Ta Instruments Waters L.L.C. | Date: 2014-08-22
A conditioning system includes a sample chamber capable of receiving a specimen as well as first and second specimen-holding fixtures positioned within the sample chamber and configured to apply mechanical stimulation to a specimen held by the fixtures. The system has at least one port capable of providing a fluid to the sample chamber. The chamber is sized and shaped so that it can be inserted into an imaging device which can record images of a specimen held by the fixtures.