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This paper presents the design and performance evaluation of a class of Phase-Frequency Detectors (PFDs) implemented utilizing only logic gates. It is a suitable candidate for applications like All-Digital Phase-Locked Loops (ADPLLs) and Delay-Locked Loops (DLLs). The proposed design is laid out in 65 nm CMOS and 22 nm FD-SOI technology and it is validated using post-extracted simulations. According to the results the proposed PFD is blind zone free and exhibits a small dead zone of ≈ 7 ps and ≈ 9 ps with a detection range of ±2π at a frequency of 10 GHz and 8 GHz in 22 nm and 65 nm, respectively. The proposed design has jitter ≈ 448 fs in 22 nm and ≈ 1.2 ps in 65 nm. The proposed PFD occupies a layout area of 115.625 μm2 and consumes 7.2 μW in 22nm and the area of the design is 225.7 μm2 and consumes 11.03 μW in 65nm. 

Abstract This study investigated the sensitivity of pyrocumulonimbus (PyroCb) induced by the California Creek fire of 2020 to the amount and type of surface fuels, within the WRF‐SFIRE modeling system. Satellite data were used to derive fire arrival times to constrain fire progression, and to augment the fuel characterization with better estimates of combustible vegetation accounting for tree mortality. Machine learning was employed to classify standing dead vegetation from aerial imagery, which was then added as a custom fuel class along with the standard Anderson fuel categories. Simulations using this new fuel class produced a larger and more vigorous PyroCb than the control run, however, still under‐predicted the cloud top. Additional augmentation of fuel mass to represent the accumulation of dead vegetation on the forest floor further improved the simulations, demonstrating the efficacy of representing both dead standing and fallen vegetation to produce more realistic PyroCb and smoke simulations. 

In this work, the effect of rapid thermal annealing (RTA) temperature on the ferroelectric polarization in zirconium-doped hafnium oxide (HZO) was studied. To maximize remnant polarization (2P r ), in-plane tensile stress was induced by tungsten electrodes under optimal RTA temperatures. We observed an increase in 2P r with RTA temperature, likely due to an increased proportion of the polar ferroelectric phase in HZO. The HZO capacitors annealed at 400°C did not exhibit any ferroelectric behavior, whereas the HZO capacitors annealed at 800°C became highly leaky and shorted for voltages above 1 V. On the other hand, annealing at 700 °C produced HZO capacitors with a record-high 2P r of ∼ 64 μ C cm −2  at a relatively high frequency of 111 kHz. These ferroelectric capacitors have also demonstrated impressive endurance and retention characteristics, which will greatly benefit neuromorphic computing applications. 

We have developed a strategy for synthesizing immediately activable, water-soluble, compact (∼10–12 nm hydrodynamic diameter) quantum dots with a small number of stable and controllable conjugation handles for long distance delivery and subsequent biomolecule conjugation. Upon covalent conjugation with engineered monovalent streptavidin, the sample results in a population consisting of low-valency quantum dots. Alternatively, we have synthesized quantum dots with a small number of biotin molecules that can self-assemble with engineered divalent streptavidin via high-affinity biotin–streptavidin interactions. Being compact, stable and highly specific against biotinylated proteins of interest, these low-valency quantum dots are ideal for labeling and tracking single molecules on the cell surface with high spatiotemporal resolution for different biological systems and applications.