Built-In Self-Test for Automatic Analog Frequency Response Measurement

Abstract-We present a Built-In Self-Test (BIST) approach based on direct digital synthesizer (DDS) for functional test of analog circuitry in mixed-signal systems. DDS with delta-sigma noise shaping is used to generate test signals with different frequencies and phases. The DDS-based BIST hardware implementation can sweep the frequencies through the interested bands and thus measure the frequency response of the analog circuit. The proposed BIST approach has been implemented in Verilog and synthesized into a Field Programmable Gate Array (FPGA). The actual device under test (DUT) was implemented using a Field Programmable Analog Array (FPAA) to form a complete BIST testbed for analog functional tests

Example code for multifiber recording from Lin Lab

MATLAB code and example videos for multifiber recording

Ion impingement effect on the structure and optical properties of Ti x Si 1− x O 2 films deposited by ICP‐PECVD

International audienc

Preparation and photocatalytic performance of TiO2-RGO-CuO/Fe2O3 ternary composite photocatalyst by solvothermal method

In this work, an one-step solvothermal synthesis method is used to prepare TiO _2 -reduced graphene oxide (RGO)-CuO/Fe _2 O _3 ternary composite photocatalysts with TiO _2 and CuO/Fe _2 O _3 nanoparticles coated RGO, while the structures and photocatalytic performance of these synthesized ternary composite photocatalysts are studied. It is found that Cu ^2+ and Fe ^3+ are substituted for Ti ^4+ into the crystal lattice of anatase TiO _2 in these prepared ternary composite photocatalysts. TiO _2 and CuO/Fe _2 O _3 nanoparticles are uniformly coated on the surface of RGO and closely contact with each other. The Cu/Fe doping has obviously improved the absorption ability on the visible light, and the bandgap of the ternary composite can be reduced. Under visible light irradiation, by increasing the Cu/Fe doping amount, the photocatalytic performance can be improved until the Cu and Fe contents reached 0.075 wt.% and 0.1 wt.%, respectively. The prepared products can be reused for eight cycles to degrade the methyl orange solution, and it retains over 93% photocatalytic efficiency

The complete mitochondrial genome of Reticulitermes ovatilabrum (Isoptera: Rhinotermitidae)

The mitochondrial genome of the Reticulitermes ovatilabrum is 15,913 bp in length and encodes 37 genes including 13 protein-coding genes (PCGs), 22 transfer RNA genes (tRNA), 2 ribosomal RNA genes (rRNA), and a non-coding control region (D-loop). The percentage of A/T (65.59%) is much higher than that of C/G (34.41%). The phylogenetic tree revealed that R. ovatilabrum was closest to R. kanmonensi and R. periflaviceps. The mitochondrial genome of the R. ovatilabrum provides a resource for evolutional analysis within termites especially Reticulitermes

Using DWS Optical Readout to Improve the Sensitivity of Torsion Pendulum

In space gravitational wave detection missions, a drag-free system is used to keep the test mass (TM) free-falling in an ultralow-noise environment. Ground verification experiments should be carried out to clarify the shielding and compensating capabilities of the system for multiple stray force noises. A hybrid apparatus was designed and analyzed based on the traditional torsion pendulum, and a technique for enhancing the sensitivity of the torsion pendulum system by employing the differential wavefront sensing (DWS) optical readout was proposed. The readout resolution experiment was then carried out on an optical bench that was designed and established. The results indicate that the angular resolution of the DWS signal in optical readout mode can reach the level of 10 nrad/Hz1/2 over the full measurement band. Compared with the autocollimator, the sensitivity of the torsional pendulum is noticeably improved, and the background noise is expected to reach 4.5 x 10-15 Nm/Hz1/2@10 mHz. This method could also be applied to future upgrades of similar systems

Fabrication of two-weir structure-based packed columns for on-chip solid-phase extraction of DNA

Microchip-based packed column SPE of DNA was performed using the microfabricated two-weir structure within a microchannel. We developed two methods to fabricate the two-weir structured glass chips: a "two-side etching/alignment" method and a simplified "one-side/two-step etching" method. The former rnethod required a straightforward alignment step, while the latter approach comprised a simplified wet etching process using paraffin wax as the temporary protective layer. Both methods were convenient and rapid as compared to the previous approaches. Through a reversibly sealed bead-introduction channel, beads can be fed into or out of the chip columns, thus enabling refreshment of the packing materials. Using the proposed chip columns, highly efficient,lambda-DNA extractions (average recovery > 80%) were performed with good chip-to-chip reproducibility (RSD < 10%). The on-chip SPE procedure was completed within 15 min at the flow rate of 3 mu L/min and the bulk of the loaded DNA was eluted within a small volume of similar to 8 mu L. Application of the microchip-based packed columns was demonstrated by purifying PCR-amplifiable genomic DNA from human hepatocellular carcinoma (HepG2) cells and human whole blood samples

Microbial Lipid Production from Corn Stover by the Oleaginous Yeast Rhodosporidium toruloides Using the PreSSLP Process

Dry acid pretreatment and biodetoxification (DryPB) has been considered as an advanced technology to treat lignocellulosic materials for improved downstream bioconversion. In this study, the lipid production from DryPB corn stover was investigated by the oleaginous yeast Rhodosporidium toruloides using a new process designated prehydrolysis followed by simultaneous saccharification and lipid production (PreSSLP). The results found that prehydrolysis at 50 degrees C and then lipid production at 30 degrees C improved lipid yield by more than 17.0% compared with those without a prehydrolysis step. The highest lipid yield of 0.080 g/g DryPB corn stover was achieved at a solid loading of 12.5%. The fatty acid distribution of lipid products was similar to those of conventional vegetable oils that are used for biodiesel production. Our results suggested that the integration of DryPB process and PreSSLP process can be explored as an improved technology for microbial lipid production from lignocellulosic materials