A carbon dioxide storage system includes a container and a conduit attached to the container for introducing or removing a carbon dioxide-containing composition from the container. A carbon dioxide storage material is positioned within the container. The carbon dioxide-storage material includes a metal-organic framework, which has a sufficient surface area to store at least 10 carbon dioxide molecules per formula unit of the metal-organic framework at a temperature of about 25° C.

Metal-organic frameworks with exceptionally high capacity for storage of carbon dioxide at room-temperature

Thin-film electronics in its myriad forms has underpinned much of the technological innovation in the fields of displays, sensors, and energy conversion over the past four decades. This technology also forms the basis of flexible electronics. Here we review the current status of flexible electronics and attempt to predict the future promise of these pervading technologies in healthcare, environmental monitoring, displays and human-machine interactivity, energy conversion, management and storage, and communication and wireless networks.

Flexible Electronics: The Next Ubiquitous Platform

Recent research in the field of phosphor and scintillator materials and related detectors is reviewed. After a historical introduction the fundamental issues are explained regarding the interaction of x-ray radiation with a solid state. Crucial parameters and characteristics important for the performance of these materials in applications, including the employed measurement methods, are described. Extended description of the materials currently in use or under intense study is given. Scintillation detector configurations are further briefly overviewed and selected applications are mentioned in more detail to provide an illustration.

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Scintillation detectors for x-rays

Digital radiography offers the potential of improved image quality as well as providing opportunities for advances in medical image management, computer-aided diagnosis and teleradiology. Image quality is intimately linked to the precise and accurate acquisition of information from the x-ray beam transmitted by the patient, i.e. to the performance of the x-ray detector. Detectors for digital radiography must meet the needs of the specific radiological procedure where they will be used. Key parameters are spatial resolution, uniformity of response, contrast sensitivity, dynamic range, acquisition speed and frame rate. The underlying physical considerations defining the performance of x-ray detectors for radiography will be reviewed. Some of the more promising existing and experimental detector technologies which may be suitable for digital radiography will be considered. Devices that can be employed in full-area detectors and also those more appropriate for scanning x-ray systems will be discussed. These include various approaches based on phosphor x-ray converters, where light quanta are produced as an intermediate stage, as well as direct x-ray-to-charge conversion materials such as zinc cadmium telluride, amorphous selenium and crystalline silicon.

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X-ray detectors for digital radiography

A review of medical diagnostic imaging methods utilizing x-rays or gamma rays and the application and development of inorganic scintillators is presented.

https://iopscience.iop.org/article/10.1088/0031-9155/47/8/201/pdf

Inorganic scintillators in medical imaging.

A multi-layer a-Si:H based thermal neutron detector was designed, fabricated and simulated by Monte Carlo method. The detector consists of two a-Si:H pin detectors prepared by plasma enhanced chemical vapor deposition (PECVD) and interfaced with coated layers of Gd, as a thermal neutron converter. Simulation results indicate that a detector consisting of 2 Gd films with thicknesses of 2 and 4 /spl mu/m, sandwiched properly with two layers of sufficiently thick (/spl sim/30 /spl mu/m) amorphous silicon diodes, has the optimum parameters. The detectors have an intrinsic efficiency of about 42% at a threshold setting of 7000 electrons, with an expected average signal size of /spl sim/12000 electrons which is well above the noise. This efficiency will be further increased to nearly 63%, if we use Gd with 50% enrichment in /sup 157/Gd. We can fabricate position sensitive detectors with spatial resolution of 300 /spl mu/m with gamma sensitivity of /spl sim/1/spl times/10/sup -5/. These detectors are highly radiation resistant and are good candidates for use in various application, where high efficiency, high resolution, gamma insensitive position sensitive neutron detectors are needed. >

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High efficiency neutron sensitive amorphous silicon pixel detectors

A compact real-time X-ray and charged-particle imager with digitized position output can be built either by coupling a fast scintillator to a photodiode array or by forming one on a photodiode array directly. CsI(Tl) layers 100-1000- mu m thick were evaporated on glass substrates from a crystal CsI(Tl). When coupled to a crystalline Si or amorphous silicon (a-Si:H) photodiode and exposed to calibrated X-ray pulses, their light yields and speed were found to be comparable to those of a crystal CsI(Tl). Single beta particle detection was demonstrated with this combination. The light spread inside evaporated CsI(Tl) was suppressed by its columnar structure. Scintillation detection gives much larger signals than direct X-ray detection due to the increased energy deposition in the detector material. Fabrication of monolithic-type X-ray sensors consisting of CsI+a-Si:H photodiodes is discussed. >

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X-ray and charged particle detection with CsI(Tl) layer coupled to a Si:H photodiode layers

We describe the properties of evaporated layers of cesium iodide (thallium activated) deposited on substrates that enable easy coupling to amorphous silicon pixel arrays. The CsI(Tl) layers range in thickness from 65 to 220 /spl mu/m. We used the two-boat evaporator system to deposit CsI(Tl) layers. This system ensures the formation of the scintillator film with homogenous thallium concentration which is essential for optimizing the scintillation light emission efficiency. The Tl concentration was kept to 0.1-0.2 mole percent for the highest light output. Temperature annealing can affect the microstructure as well as light output of the CsI(Tl) film. 200-360/spl deg/C temperature annealing can increase the light output by a factor of two. The amorphous silicon pixel arrays are p-i-n diodes approximately 1 /spl mu/m thick with transparent electrodes to enable them to detect the scintillation light produced by X-rays incident on the CsI(Tl). Digital radiography requires a good spatial resolution. This is accomplished by making the detector pixel size less than 50 /spl mu/m. The light emission from the CsI(Tl) is collimated by techniques involving the deposition process on patterned substrates. We have measured MTF of greater than 12 line pairs per mm at the 10% level. >

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Amorphous silicon pixel layers with cesium iodide converters for medical radiography

A highly sensitive charge-sensitive amplifier IC was used to read out large-area two-dimensional arrays of amorphous silicon (a-Si) p-i-n photodiodes addressed by a-Si thin film transistors (TFTs). At the highest sensitivity mode, the random noise of the sensor was equivalent to an input charge of 1500 electrons rms. Feedthrough charge injection associated with TFT switching had to be avoided at the expense of the signal charge. Image lag caused by charge trapping in a-Si was suppressed by limiting the input light intensity. A simple model was developed for the noise contribution from a pixel and compared with measurements.

G. Cho

Papers

High efficiency neutron sensitive amorphous silicon pixel detectors

X-ray and charged particle detection with CsI(Tl) layer coupled to a Si:H photodiode layers

Amorphous silicon pixel layers with cesium iodide converters for medical radiography

Amorphous silicon pixel layers with cesium iodide converters for medical radiography

High Sensitivity Readout of 2D a-Si Image Sensors