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  1. Microscale heating platforms capable of generating localized temperature rises can find applications in wide‐ranging areas including nanomaterials synthesis and microscale thermometry. Here, commercially available optical calibration samples called Ronchi rulings, which consist of an array of chrome lines on a float glass substrate, are demonstrated to serve as reconfigurable Joule heaters. Electrical connections are formed by wire bonding onto the chrome to Joule heat individual lines and monitor their temperature rises using electrical resistance thermometry. Tests across multiple heater lines demonstrate a negative temperature coefficient of resistance with an average value of −6.93 × 10−4 ± 8.18 × 10−5 K−1. Under Joule heating, temperature rises exceeding 100 K are measured. To characterize the temperature gradient across the chrome line and glass, a noncontact optical thermometry technique based on the temperature‐dependent luminescence of upconverting nanoparticles (UCNPs) is used, producing temperature measurements that match finite element simulations. A 1:1 area ratio between the chrome lines and glass offers a high probability of finding UCNPs across both materials. The temperature rise on chrome determined from luminescence thermometry, electrical resistance thermometry, and simulations are also consistent. Furthermore, over 50% of the peak temperature rise is maintained along the neighboring glass region. 
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  2. Understanding howAI recommendationswork can help the younger generation become more informed and critical consumers of the vast amount of information they encounter daily. However, young learners with limited math and computing knowledge often find AI concepts too abstract. To address this, we developed Briteller, a light-based recommendation system that makes learning tangible. By exploring and manipulating light beams, Briteller enables children to understand an AI recommender system’s core algorithmic building block, the dot product, through hands-on interactions. Initial evaluations with ten middle school students demonstrated the effectiveness of this approach, using embodied metaphors, such as "merging light" to represent addition. To overcome the limitations of the physical optical setup, we further explored how AR could embody multiplication, expand data vectors with more attributes, and enhance contextual understanding. Our findings provide valuable insights for designing embodied and tangible learning experiences that make AI concepts more accessible to young learners. 
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  3. Environmental energy harvesting provides a sustainable solution to energy shortages using clean, renewable sources. Despite advances in technologies like triboelectric nanogenerators (TENGs) and electromagnetic generators (EMGs), many devices are limited to a single‐energy source and specific conditions, limiting their practical applications. This study presents an innovative amphibious hybrid TENG–EMG (HTEG) that overcomes these limitations by coupling TENG and EMG units with a gear set, amplifying power output through rotational motion. The amphibious HTEG efficiently captures and converts energy from various environmental sources, successfully illuminating over 30 light‐emitting diodes and powering a thermohygrometer. Notably, it operates with minimal speed requirements, harnessing energy from a light breeze of 1.56 m s1or a small water flow of 3.8 L min1, a significant advantage given that most existing devices require much higher speeds for efficient energy harvesting. Moreover, the amphibious HTEG approves practical for daily outdoor use, such as charging mobile phones and powering small electronics through natural energy sources. Furthermore, it can be manually operated without the need for external elements. This compact, portable, and effective energy harvesting design showcases the ability to capture natural energy across diverse environments, demonstrating it as a versatile solution with significant potential for real‐world applications. 
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  4. To increase the storage capacity of hard disk drives, Heat-Assisted Magnetic Recording (HAMR) takes advantage of laser heating to temporarily reduce the coercivity of recording media, enabling the writing of very small data bits on materials with high thermal stability. One key challenge in implementing HAMR is effective thermal management, which requires reliable determination of the thermal properties of HAMR materials over their range of operating temperature. This work reports the thermal properties of dielectric (amorphous silica, amorphous alumina, and AlN), metallic (gold and copper), and magnetic alloy (NiFe and CoFe) thin films used in HAMR heads from room temperature to 500 K measured with time-domain thermoreflectance. Our results show that the thermal conductivities of amorphous silica and alumina films increase with temperature, following the typical trends for amorphous materials. The polycrystalline AlN film exhibits weak thermal anisotropy, and its in-plane and through-plane thermal conductivities decrease with temperature. The measured thermal conductivities of AlN are significantly lower than that which would be present in single-crystal bulk material, and this is attributed to enhanced phonon-boundary scattering and phonon-defect scattering. The gold, copper, NiFe, and CoFe films show little temperature dependence in their thermal conductivities over the same temperature range. The measured thermal conductivities of gold and copper films are explained by the diffuse electron-boundary scattering using an empirical model. 
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  5. Abstract MicroRNAs (miRNAs) play a key role in regulating gene expression and their biogenesis is precisely controlled through modulating the activity of microprocessor. Here, we report that CWC15, a spliceosome-associated protein, acts as a positive regulator of miRNA biogenesis. CWC15 binds the promoters of genes encoding miRNAs (MIRs), promotes their activity, and increases the occupancy of DNA-dependent RNA polymerases at MIR promoters, suggesting that CWC15 positively regulates the transcription of primary miRNA transcripts (pri-miRNAs). In addition, CWC15 interacts with Serrate (SE) and HYL1, two key components of microprocessor, and is required for efficient pri-miRNA processing and the HYL1-pri-miRNA interaction. Moreover, CWC15 interacts with the 20 S proteasome and PRP4KA, facilitating SE phosphorylation by PRP4KA, and subsequent non-functional SE degradation by the 20 S proteasome. These data reveal that CWC15 ensures optimal miRNA biogenesis by maintaining proper SE levels and by modulating pri-miRNA levels. Taken together, this study uncovers the role of a conserved splicing-related protein in miRNA biogenesis. 
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