Enhancing the cycling stability of Co-free high-Ni layered cathodes through MgO surface engineering.

A magnesium oxide (MgO) coating strategy is proposed for improving the cobalt-free high-nickel LiNiMnO cathode. It is revealed that a MgO coating can stabilize reversible Ni/Ni redox and suppress structural degradation. The MgO coated LiNiMnO exhibits a promising capacity retention of 66.

Tetrahedral Occupied V Ions Enabling Reversible Three-Electron Redox of Cr /Cr in Layered Cathode Materials for Potassium-Ion Batteries.

Reversible three-electron redox of Cr /Cr in layered cathode materials for rechargeable batteries is very attractive in layered cathode materials, which leads to high capacity and energy density for rechargeable batteries. However, the poor reversibility and Cr-ion migration make it very challenging. In this work, by introducing V ions into tetrahedral sites of layer-structured NaCrO , reversible three-electron redox of Cr /Cr is realized successfully in NaCr V O (NCV05) cathode for potassium-ion batteries with a cut-off voltage of 4.

An Experimental Study of the Mechanical Properties of Partially Rehabilitated Cable Tunnels.

For buried municipal tunnels-such as cable tunnels and utility tunnels with structural defects-due to the sheltering of the internal pipelines, shelves, and other auxiliary facilities, traditional trenchless rehabilitating methods are not applicable since an intact ring is needed for spraying and lining. In these tunnels, only the exposed area at the crown of the ring can be partly rehabilitated. In this paper, three-edge bearing tests (TEBTs) for partially rehabilitated reinforced concrete (RC) pipe sections are carried out to simulate the case of a municipal tunnel and the effects of different repair materials (cement mortar and epoxy resin) and different dimensional parameters of the liner (lining thickness, lining range) on the partial rehabilitation effect of defective RC pipes are studied.

Void distributions reveal structural link between jammed packings and protein cores.

Dense packing of hydrophobic residues in the cores of globular proteins determines their stability. Recently, we have shown that protein cores possess packing fraction ϕ≈0.56, which is the same as dense, random packing of amino-acid-shaped particles.

Computational cell analysis for label-free detection of cell properties in a microfluidic laminar flow.

Although a flow cytometer, being one of the most popular research and clinical tools for biomedicine, can analyze cells based on the cell size, internal structures such as granularity, and molecular markers, it provides little information about the physical properties of cells such as cell stiffness and physical interactions between the cell membrane and fluid. In this paper, we propose a computational cell analysis technique using cells' different equilibrium positions in a laminar flow. This method utilizes a spatial coding technique to acquire the spatial position of the cell in a microfluidic channel and then uses mathematical algorithms to calculate the ratio of cell mixtures.

Integrated 1550 nm photoreceiver with built-in amplification and feedback mechanisms.

Sensitivity, dynamic range and detection efficiency are among the key figures of merit for 1550 nm wavelength detectors that find applications in communications, sensing, and imaging. Some fundamental material and device limits have added tremendous difficulties for a single device to achieve high sensitivity and dynamic range without significant trade-offs. We present a concept that can potentially overcome this performance bottleneck.

Label-free Optofluidic Cell Classifier Utilizing Support Vector Machines.

A unique optofluidic lab-on-a-chip device that can measure optically encoded forward scattering signals has been demonstrated. From the design of the spatial pattern, the position and velocity of each cell in the flow can be detected and then a spatial cell distribution over the cross section of the channel can be generated. According to the forward scattering intensity and position information of cells, a data-mining method, support vector machines (SVMs), is applied for cell classification.

Universally applicable three-dimensional hydrodynamic microfluidic flow focusing.

We have demonstrated a microfluidic device that can not only achieve three-dimensional flow focusing but also confine particles to the center stream along the channel. The device has a sample channel of smaller height and two sheath flow channels of greater height, merged into the downstream main channel where 3D focusing effects occur. We have demonstrated that both beads and cells in our device display significantly lower CVs in velocity and position distributions as well as reduced probability of coincidental events than they do in conventional 2D-confined microfluidic channels.

Counting leukocytes from whole blood using a lab-on-a-chip Coulter counter.

A microfluidic lab-on-a-chip Coulter counter was demonstrated to count micro particles and leukocytes from whole blood. Instead of electroplated or deposited metal electrodes, off-the-shelf gold pins were used as electrodes to simplify fabrication process, reduce cost, enhance device durability, and above all, achieve superior uniformity in E-field distribution for improved signal quality. A custom-designed, low-cost demodulation circuit was developed to detect the AC impedance signals of the particles and cells passing the detection area defined by the microfluidic channels.

Optofluidic device for label-free cell classification from whole blood.

We demonstrated a unique optofluidic lab-on-a-chip device that can measure optically encoded forward scattering signals. From the design of the spatial pattern, we can measure the position and velocity of each cell in the flow and generate a 2-D cell distribution plot over the cross section of the channel. Moreover, we have demonstrated that the cell distribution is highly sensitive to its size and stiffness.

An optical-coding method to measure particle distribution in microfluidic devices.

We demonstrated an optical coding method to measure the position of each particle in a microfluidic channel. The technique utilizes a specially designed pattern as a spatial mask to encode the forward scattering signal of each particle. From the waveform of the forward scattering signal, one can obtain the information about the particle position and velocity.

Applying an optical space-time coding method to enhance light scattering signals in microfluidic devices.

An "optical space-time coding method" was applied to microfluidic devices to detect the forward and large angle light scattering signals for unlabelled bead and cell detection. Because of the enhanced sensitivity by this method, silicon pin photoreceivers can be used to detect both forward scattering (FS) and large angle (45-60°) scattering (LAS) signals, the latter of which has been traditionally detected by a photomultiplier tube. This method yields significant improvements in coefficients of variation (CV), producing CVs of 3.