| 1. |
- Sun, Jie, 1977, et al.
(författare)
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Electrochemical Bubbling Transfer of Graphene Using a Polymer Support with Encapsulated Air Gap as Permeation Stopping Layer
- 2016
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Ingår i: Journal of Nanomaterials. - : Hindawi Limited. - 1687-4129 .- 1687-4110. ; 2016
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Tidskriftsartikel (refereegranskat)abstract
- Electrochemical bubbling transfer of graphene is a technique with high industrial potential due to its scalability, time- and cost-effectiveness, and ecofriendliness. However, the graphene is often damaged due to the turbulence and the trapped bubbles formed by the direct H2O and H+ permeation through the supporting polymer. We invent a graphene mechanical support of polyethylene terephthalate foil/plastic frame/poly(methyl methacrylate) sandwich, with an encapsulated air gap as the permeation stopping layer. The graphene damage is drastically reduced, as confirmed by the morphology and structural and electrical characterization, ultimately improving the controllability/reproducibility of the bubbling transfer of graphene and other two-dimensional materials.
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| 2. |
- Sun, Jie, 1977, et al.
(författare)
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Synthesis Methods of Two-Dimensional MoS2: A Brief Review
- 2017
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Ingår i: Crystals. - : MDPI AG. - 2073-4352. ; 7:7, s. Article no 198 -
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Forskningsöversikt (refereegranskat)abstract
- Molybdenum disulfide (MoS2) is one of the most important two-dimensional materials after graphene. Monolayer MoS2 has a direct bandgap (1.9 eV) and is potentially suitable for post-silicon electronics. Among all atomically thin semiconductors, MoS2's synthesis techniques are more developed. Here, we review the recent developments in the synthesis of hexagonal MoS2, where they are categorized into top-down and bottom-up approaches. Micromechanical exfoliation is convenient for beginners and basic research. Liquid phase exfoliation and solutions for chemical processes are cheap and suitable for large-scale production; yielding materials mostly in powders with different shapes, sizes and layer numbers. MoS2 films on a substrate targeting high-end nanoelectronic applications can be produced by chemical vapor deposition, compatible with the semiconductor industry. Usually, metal catalysts are unnecessary. Unlike graphene, the transfer of atomic layers is omitted. We especially emphasize the recent advances in metalorganic chemical vapor deposition and atomic layer deposition, where gaseous precursors are used. These processes grow MoS2 with the smallest building-blocks, naturally promising higher quality and controllability. Most likely, this will be an important direction in the field. Nevertheless, today none of those methods reproducibly produces MoS2 with competitive quality. There is a long way to go for MoS2 in real-life electronic device applications.
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| 3. |
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| 4. |
- Dong, Y. B., et al.
(författare)
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Transfer-free, lithography-free, and micrometer-precision patterning of CVD graphene on SiO 2 toward all-carbon electronics
- 2018
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Ingår i: APL Materials. - : AIP Publishing. - 2166-532X. ; 6:2
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Tidskriftsartikel (refereegranskat)abstract
- A method of producing large area continuous graphene directly on SiO 2 by chemical vapor deposition is systematically developed. Cu thin film catalysts are sputtered onto the SiO 2 and pre-patterned. During graphene deposition, high temperature induces evaporation and balling of the Cu, and the graphene "lands onto" SiO 2 . Due to the high heating and growth rate, continuous graphene is largely completed before the Cu evaporation and balling. 60 nm is identified as the optimal thickness of the Cu for a successful graphene growth and μm-large feature size in the graphene. An all-carbon device is demonstrated based on this technique.
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| 5. |
- Feng, Z., et al.
(författare)
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Spectrally overlaid DDO-OFDM transmission enabled by optical power division multiplexing
- 2017
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Ingår i: ICOCN 2016 - 2016 15th International Conference on Optical Communications and Networks. - : IEEE. - 9781509034918
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Konferensbidrag (refereegranskat)abstract
- Two 8.3-Gb/s spectrally overlaid DDO-OFDM signals are successfully transmitted along 50-km SMF using optical power division multiplexing and received by a successive interference cancellation (SIC) receiver. Spectral efficiency is doubled with optimized optical modulation index and optical power division ratio.
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| 6. |
- Bogaerts, W., et al.
(författare)
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Low-Power Electro-Optic Actuators for Large-Scale Programmable Photonic Circuits
- 2021
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Ingår i: 2021 Conference on Lasers and Electro-Optics, CLEO 2021 - Proceedings. - : Institute of Electrical and Electronics Engineers Inc..
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Konferensbidrag (refereegranskat)abstract
- Photonic integrated circuits are becoming increasingly more complex, especially with the emergence of programmable photonic circuits. These require many tunable photonic elements, such as electro-optic phase shifters and tunable couplers. We will discuss our progress in compact, low-power silicon photonics actuators based on heaters, liquid crystal and MEMS that can be scaled up to large circuits.
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| 7. |
- Xu, K., et al.
(författare)
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Graphene GaN-Based Schottky Ultraviolet Detectors
- 2015
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Ingår i: IEEE Transactions on Electron Devices. - : Institute of Electrical and Electronics Engineers (IEEE). - 1557-9646 .- 0018-9383. ; 62:9, s. 2802-2808
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Tidskriftsartikel (refereegranskat)abstract
- Graphene GaN-based Schottky ultraviolet detectors are fabricated. The monolayer graphene is grown by chemical vapor deposition. The graphene is much more transparent than metals, as confirmed by the fact that our devices retain their high responsivity up to 360-nm wavelength (corresponding to the band edge absorption of GaN). Importantly, by virtue of the tunable work function of graphene, the graphene GaN Schottky barrier height can be greatly enlarged. The built-in field is enhanced, and the detector performance is improved. The current ratio with and without luminescence is up to 1.6 x 10(4). The characteristic time constants of the devices are in the order of a few milliseconds. The device open-circuit voltage and short-circuit current are also increased. At last, special type Schottky devices consisting of GaN nanorods or surface-etched GaN are prepared for complementary study. It is found although the dry etching induced surface defects lead to an increase in the dark current, and these carrier traps also greatly contribute to the photoconductivity under luminescence, resulting in extraordinarily large responsivity (up to 360 A/W at -6 V).
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| 8. |
- Deng, N.X., et al.
(författare)
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Pressroom runnability : comprehensive analyses of pressroom and mill databases
- 2005
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Ingår i: Annual Meeting of the Pulp and Paper Technical Association of Canada (PAPTAC). - : Pulp and Paper Technical Association of Canada. - 1897023081 ; , s. C217-228
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Web break is an important runnability issue in the pressrooms. However, web breaks are rare events. Performance statistics for a large number of rolls are required to determine the causes of runnability problems with a reasonable level of confidence. To provide better insight into the main causes of web breaks, we analyzed seven pressroom/mill databases of sufficient size to produce reliable runnability statistics. The statistical "association" between strength properties (average) and break rate was examined using a Chi Square analysis method. We found that the statistical "association" between strength properties (average) and break rate varied considerably from one pressroom to the other (or from one mill to the other), depending on the pressroom operation (the variations of tension) and the quality of data from mills. However, among different strength properties, MD tensile strength has been most consistently associated with the break rate. CD Tear strength did not consistently predict the runnability. We also found that strength uniformity had a significant impact on pressroom performance. Lastly, the pressroom data consistently showed that typical, macroscopic defects are now minority causes for web breaks and the majority of breaks are press-related or "unknown".
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| 9. |
- Deng, X., et al.
(författare)
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Pressroom Runnability : A Comprehensive Analysis of Press Room and Mill Database
- 2007
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Ingår i: Pulp & paper Canada. - 0316-4004. ; 108:2, s. 42-51
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Tidskriftsartikel (refereegranskat)abstract
- Web break is an important runnability issue in the pressrooms. However, web breaks are rare events. Performance statistics for a large number of rolls are required to determine the causes of runnability problems with a reasonable level of confidence. To provide better insight into the main causes of web breaks, we analyzed seven pressroom/mill databases of sufficient size to produce reliable runnability statistics. The statistical "association" between strength properties (average) and break rate was examined using a Chi Square analysis method. We found that the statistical "association" between strength properties (average) and break rate varied considerably from one pressroom to the other (or from one mill to the other), depending on the pressroom operation (the variations of tension) and the quality of data from mills. However, among different strength properties, MD tensile strength has been most consistently associated with the break rate. CD tear strength did not consistently predict the runnability. We also found that strength uniformity had a significant impact on pressroom performance. Lastly, the pressroom data consistently showed that typical, macroscopic defects are now minority causes for web breaks and the majority of breaks are press-related or "unknown".
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| 10. |
- Qi, W, et al.
(författare)
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Denitrification performance and microbial communities of solid-phase denitrifying reactors using poly (butylene succinate)/bamboo powder composite
- 2020
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Ingår i: Bioresource Technology. - : Elsevier Ltd. - 0960-8524 .- 1873-2976. ; 305
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Tidskriftsartikel (refereegranskat)abstract
- This study explored the denitrification performance of solid-phase denitrification (SPD) systems packed with poly (butylene succinate)/bamboo powder composite to treat synthetic aquaculture wastewater under different salinity conditions (0‰ Vs. 25‰). The results showed composite could achieve the maximum denitrification rates of 0.22 kg (salinity, 0‰) and 0.34 kg NO3−-N m−3 d−1 (salinity, 25‰) over 200-day operation. No significant nitrite accumulation and less dissolved organic carbon (DOC) release (<15 mg/L) were found. The morphological and spectroscopic analyses demonstrated the mixture composites degradation. Microbial community analysis showed that Acidovorax, Simplicispira, Denitromonas, SM1A02, Marinicella and Formosa were the dominant genera for denitrifying bacteria, while Aspergillus was the major genus for denitrifying fungus. The co-network analysis also indicated the interactions between bacterial and fungal community played an important role in composite degradation and denitrification. The outcomes provided a potential strategy of DOC control and cost reduction for aquaculture nitrate removal by SPD.
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