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At last week's IEEE International Electron Devices Meeting (IEDM) in San Francisco (USA), imec, the world-leading research and innovation hub in nano-electronics and digital technology and Holst Centre debuted a miniaturized sensor that simultaneously determines pH and chloride (Cl-)levels in fluid. This innovation is a must have for accurate long-term measurement of ion concentrations in applications such as environmental monitoring, precision agriculture and diagnostics for personalized healthcare. The sensor is an industry first and thanks to the SoC (system on chip) integration it enables massive and cost-effective deployments in Internet-of-Things (IoT) settings. Its innovative electrode design results in a similar or better performance compared to today's standard equipment for measuring single ion concentrations and allows for additional ion tests.Sensors based on ion-selective membranes are considered the gold standard to measure ion concentrations in many applications, such as water quality, agriculture, and analytical chemistry. They consist of two electrodes, the ion-sensitive electrode with the membrane (ISE) and a reference electrode (RE). When these electrodes are immersed in a fluid, a potential is generated that scales with the logarithm of the ion activity in the fluid, forming a measure for the concentration. However, the precision of the sensor depends on the long-term stability of the miniaturized RE, a challenge that has now been overcome."The common issue with such designs is the leaching of ions from the internal electrolyte, causing the sensor to drift over time," stated Marcel Zevenbergen, senior researcher at imec/Holst Centre. "To suppress such leaching, we designed and fabricated an RE with a microfluidic channel as junction and combined it with solid-state iridium oxide (IrOx) and silver chloride (AgCl) electrodes fabricated on a silicon substrate, respectively as indicating electrodes for pH and Cl-. Our tests demonstrated this to be a long-term stable solution with the sensor showing a sensitivity, accuracy and response time that are equal or better than existing solutions, while at the same time being much smaller and potentially less expensive.""We are providing groundbreaking sensing and analytics solutions for the IoT," stated John Baekelmans, Managing Director of imec in The Netherlands. "This new multi-ion sensor is one in a series that Holst Centre is currently developing with its partners to form the senses of the IoT. For each sensor, the aim is to leapfrog the current performance of the state-of-the-art sensors in a mass-producible, wireless, energy optimized and miniaturized package."Reference:ADXRS620BBGZLPY410ALTRL3GD20HTR  

An ISA100 Wireless-based field wireless vibration sensor from Yokogawa has the ability to quickly update data as well as a long battery life. ISA100 Wireless is a technology that is based on the ISA100.11a standard. It includes ISA100.11a-2011 communications, an application layer with process control industry standard objects, device descriptions and capabilities, a gateway interface, infrared provisioning, and a backbone router.By providing real-time updates on vibration levels in plant facilities, the new sensor helps users quickly detect equipment anomalies and enables predictive maintenance.With a field wireless system, plant field devices and analysers are able to communicate wirelessly with host-level monitoring and control systems.The rising need to improve productivity and enhance safety by collecting more data on plant operations is driving the demand for field wireless devices, which can be installed even in difficult to access locations.Field wireless devices have the added advantage of reducing installation costs.Vibration sensors are useful for the condition monitoring and predictive maintenance of plant machinery such as compressors, pumps, and motors.Conventional methods for monitoring vibration include the use of vibration sensors that rely on wired communications with a host system, and patrols by maintenance staff to collect vibration data.With the widening use of field wireless systems and the need to reduce installation costs, there is an increasing demand for wireless vibration sensors.Since releasing the world’s first ISA100 Wireless-based field wireless devices and wireless systems, Yokogawa has expanded its lineup of field wireless devices that measure temperature, pressure, flow rate, and the like.This new vibration sensor will meet the company’s customers’ needs for a device that can provide the quick updates on vibration levels needed to detect anomalies at an early stage.The principal components of this field wireless vibration sensor are the FN510 field wireless multifunction module, the LN01 piezoelectric type acceleration sensor, and the FN110 field wireless communication module.Via a gateway device, the FN510 uses the ISA100 Wireless communications protocol to exchange data with a host-level system such as a DCS. The data collected with this vibration sensor enables plant operators and maintenance staff to monitor vibration levels in real time. Both explosion-proof and non-explosion-proof types are available.Reference:D7E-1BU-27135-0001005447-1   

Researchers have proposed a design for the first DNA sequencer based on an electronic nanosensor that can detect tiny motions as small as a single atom. The proposed device—a type of capacitor, which stores electric charge—is a tiny ribbon of molybdenum disulfide suspended over a metal electrode and immersed in water. The ribbon is 15.5 nanometers (nm, billionths of a meter) long and 4.5 nm wide. Single-stranded DNA, containing a chain of bases (bits of genetic code), is threaded through a hole 2.5 nm wide in the thin ribbon. The ribbon flexes only when a DNA base pairs up with and then separates from a complementary base affixed to the hole. The membrane motion is detected as an electrical signal. As described in a new paper, the NIST team made numerical simulations and theoretical estimates to show the membrane would be 79 to 86 percent accurate in identifying DNA bases in a single measurement at speeds up to about 70 million bases per second. Integrated circuits would detect and measure electrical signals and identify bases. The results suggest such a device could be a fast, accurate and cost-effective DNA sequencer, according to the paper. Conventional sequencing, developed in the 1970s, involves separating, copying, labeling and reassembling pieces of DNA to read the genetic information. Newer methods include automated sequencing of many DNA fragments at once—still costly—and novel "nanopore sequencing" concepts. For example, the same NIST group recently demonstrated the idea of sequencing DNA by passing it through a graphene nanopore, and measuring how graphene's electronic properties respond to strain. The latest NIST proposal relies on a thin film of molybdenum disulfide—a stable, layered material that conducts electricity and is often used as a lubricant. Among other advantages, this material does not stick to DNA, which can be a problem with graphene. The NIST team suggests the method might even work without a nanopore—a simpler design—by passing DNA across the edge of the membrane. "This approach potentially solves the issue with DNA sticking to graphene if inserted improperly, because this approach does not use graphene, period," NIST theorist and lead author Alex Smolyanitsky said. "Another major difference is that instead of relying on the properties of graphene or any particular material used, we read motions electrically in an easier way by forming a capacitor. This makes any electrically conductive membrane suitable for the application." Nanomaterials expert Boris Yakobson of Rice University, a co-author on the paper, suggested the capacitor idea. Computational support was provided by the University of Groningen in the Netherlands. DNA has four bases. For the simulations, cytosine (C), which naturally pairs up with guanine (G), is attached to the inside of the pore. When a piece of DNA passes through the pore, any G in the strand temporarily attaches to the embedded C, pulling on the nanoribbon and signaling the electrode. The DNA sequence is determined by measuring how and when electrical blips vary over time. To detect all four bases, four nanoribbons, each with a different base attached to the pore, could be stacked vertically to create an integrated DNA sensor. The molybdenum disulfide ribbon is flexible enough to deform measurably in response to the forces required to break up a DNA pair, but rigid enough to have less ongoing, meaningless movement than graphene, potentially reducing unwanted noise in the sequencing signals. The deflection of the ribbon is exceedingly small, on the order of one angstrom, the size of a hydrogen atom. Its pulling force is on the order of 50 piconewtons, or trillionths of a newton, enough to break up the delicate chemical bonds between DNA bases. Researchers estimated how the device would perform in an integrated circuit and found the peak currents through the capacitor were measurable (50 to 70 picoamperes), even for the small nanoribbons studied. The current peaks are expected to be even larger in physical systems. The device size could be tweaked to make it even easier to measure sequencing signals. The NIST authors hope to build a physical version of the device in the future. For practical applications, the chip-sized DNA sequencing microfluidic technology might be combined with electronics into a single device small enough to be handheld. Reference: RFCS04021000BJTT1 RFCS04025000DBTT1 SC02201518    

A capacitive touch sensor display that provides a more intuitive interface to ease and accelerate user interactions has been developed by VCC. The LED-based CTH series capacitive touch sensor display combines graphic interactive control with colour identification to make the interface more user-friendly.Utilising sensitive capacitive touch sensing technology, the CTH series simplifies designs and offers cost savings by eliminating the need for a traditional switch.The LED display produces a high-optical clarity, and is offered with or without a wide variety of standard graphic overlays and colours. VCC can also develop custom icons to meet most any application requirement. Offered in a wide variety of colours including red, yellow, blue, pure green and white, the LED back-lit CTH series. The robust design has no moving parts, improving reliability and increasing the operational life.Featuring a through hole design, the capacitive touch sensor display is available in one standard size 15x15x11.0mm with an industry standard pitch of 0.100"."Featuring translucent icons illuminated with different coloured LEDs, the user friendly CTH series display offers superior device interaction by communicating a singular action to users such as on/off, alarm status, and more," said Sannah Vinding, Director of Product Development and Marketing at VCC. "The integrated functionality of the compact CTH series capacitive touch sensor display eliminates the need for designing-in a traditional switch. Unlike mechanical membrane switches or mechanical push buttons, capacitive touch keypads have no moving parts so there is nothing to wear out."The CTH series is used in a wide range of applications including appliances, consumer equipment, gaming devices, industrial control displays, media players, medical devices, mobile communication devices, PDAs, point of sale terminals, portable instruments, touch screen monitors and more.Reference:T141AM61STMPE1208SQTRQT1101-ISGAT42QT2100-AUR  

Use of copper as a fluorescent material allows for the manufacture of inexpensive and environmentally compatible organic light-emitting diodes (OLEDs). Thermally activated delayed fuorescence (TADF) ensures high light yield. Scientists of Karlsruhe Institute of Technology (KIT), CYNORA, and the University of St Andrews have now measured the underlying quantum mechanics phenomenon of intersystem crossing in a copper complex. The results of this fundamental work are reported in the Science Advances journal and contribute to enhancing the energy efficiency of OLEDs.  Organic light-emitting diodes are deemed tomorrow's source of light. They homogeneously emit light in all observation directions and produce brilliant colors and high contrasts. As it is also possible to manufacture transparent and flexible OLEDs, new application and design options result, such as flat light sources on window panes or displays that can be rolled up. OLEDs consist of ultra-thin layers of organic materials, which serve as emitter and are located between two electrodes. When voltage is applied, electrons from the cathode and holes (positive charges) from the anode are injected into the emitter, where they form electron-hole pairs. These so-called excitons are quasiparticles in the excited state. When they decay into their initial state again, they release energy.Excitons may assume two different states: Singlet excitons decay immediately and emit light, whereas triplet excitons release their energy in the form of heat. Usually, 25 percent singlets and 75 percent triplets are encountered in OLEDs. To enhance energy efficiency of an OLED, also triplet excitons have to be used to generate light. In conventional light-emitting diodes heavy metals, such as iridium and platinum, are added for this purpose. But these materials are expensive, have a limited availability, and require complex OLED production methods.It is cheaper and environmentally more compatible to use copper complexes as emitter materials. Thermally activated delayed fluorescence (TADF) ensures high light yields and, hence, high efficiency: Triplet excitons are transformed into singlet excitons which then emit photons. TADF is based on the quantum mechanics phenomenon of intersystem crossing (ISC), a transition from one electronic excitation state to another one of changed multiplicity, i.e. from singlet to triplet or vice versa. In organic molecules, this process is determined by spin-orbit coupling. This is the interaction of the orbital angular momentum of an electron in an atom with the spin of the electron. In this way, all excitons, triplets and singlets, can be used for the generation of light. With TADF, copper luminescent material reaches an efficiency of 100 percent.Stefan Bräse and Larissa Bergmann of KIT's Institute of Organic Chemistry (IOC), in cooperation with researchers of the OLED technology company CYNORA and the University of St Andrews, United Kingdom, for the first time measured the speed of intersystem crossing in a highly luminescent, thermally activated delayed fluorescence copper(I) complex in the solid state. The results are reported in the Science Advances journal. The scientists determined a time constant of intersystem crossing from singlet to triplet of 27 picoseconds (27 trillionths of a second). The reverse process – reverse intersystem crossing – from triplet to singlet is slower and leads to a TADF lasting for an average of 11.5 microseconds. These measurements improve the understanding of mechanisms leading to TADF and facilitate the specific development of TADF materials for energy-efficient OLEDs.Reference:KY59-0202NYKY59-S101D2LCD-S301C31TR 

How can quantum information be stored as long as possible? An important step forward in the development of quantum memories has been achieved by a research team of TU Wien.Conventional memories used in today's computers only differentiate between the bit values 0 and 1. In quantum physics, however, arbitrary superpositions of these two states are possible. Most of the ideas for new quantum technology devices rely on this "Superposition Principle". One of the main challenges in using such states is that they are usually short-lived. Only for a short period of time can information be read out of quantum memories reliably, after that it is irrecoverable.A research team at TU Wien has now taken an important step forward in the development of new quantum storage concepts. In cooperation with the Japanese telecommunication giant NTT, the Viennese researchers lead by Johannes Majer are working on quantum memories based on nitrogen atoms and microwaves. The nitrogen atoms have slightly different properties, which quickly leads to the loss of the quantum state. By specifically changing a small portion of the atoms, one can bring the remaining atoms into a new quantum state, with a lifetime enhancement of more than a factor of ten. These results have now been published in the journal Nature Photonics.Nitrogen in diamond"We use synthetic diamonds in which individual nitrogen atoms are implanted", explains project leader Johannes Majer from the Institute of Atomic and Subatomic Physics of TU Wien. "The quantum state of these nitrogen atoms is coupled with microwaves, resulting in a quantum system in which we store and read information."However, the storage time in these systems is limited due to the inhomogeneous broadening of the microwave transition in the nitrogen atoms of the diamond crystal. After about half a microsecond, the quantum state can no longer be reliably read out, the actual signal is lost. Johannes Majer and his team used a concept known as "spectral hole burning", allowing data to be stored in the optical range of inhomogeneously broadened media, and adapted it for supra-conducting quantum circuitsand spin quantum memories.Dmitry Krimer, Benedikt Hartl and Stefan Rotter (Institute of Theoretical Physics, TU Wien) have shown in their theoretical work that such states, which are largely decoupled from the disturbing noise, also exist in these systems. "The trick is to manoeuver the quantum system into these durable states through specific manipulation, with the aim to store information there," explains Dmitry Krimer.Excluding specific energies"The transitions areas in the nitrogen atoms have slightly different energy levels because of the local properties of the not quite perfect diamond crystal", explains Stefan Putz, the first author of the study, who has since moved from TU Wien to Princeton University. "If you use microwaves to selectively change a few nitrogen atoms that have very specific energies, you can create a "Spectral Hole". The remaining nitrogen atoms can then be brought into a new quantum state, a so-called "dark state", in the center of these holes. This state is much more stable and opens up completely new possibilities.""Our work is a 'proof of principle' – we present a new concept, show that it works, and we want to lay the foundations for further exploration of innovative operational protocols of quantum data," says Stefan Putz.With this new method, the lifetime of quantum states of the coupled system of microwaves and nitrogen atoms increased by more than one order of magnitude to about five microseconds. This is still not a great deal in the standard of everyday life, but in this case it is sufficient for important quantum-technological applications. "The advantage of our system is that one can write and read quantum information within nanoseconds," explains Johannes Majer. "A large number of working steps are therefore possible in microseconds, in which the system remains stable."Reference: S29GL032N11FFIS42S29GL064N90FFIS30S29AS016J70BFA040