Singapore

PVA is a polymer containing a large number of hydroxyl groups, which can be used by microorganisms as a source of carbon and energy. Water-soluble PVA has three major advantages: good abrasion resistance, high oil resistance, and high viscosity. Narrow intermolecular gaps and strong intermolecular forces caused the PVA hydroxyl groups for etherification and acetalization reactions to form a flexible film. In this research, The polyvinyl alcohol (PVA) nanofibers with good water resistance and high orientation were prepared by electrospinning technology, and PVA fiber self reinforced PVA resin matrix composite membrane with high strength and high transmittance was successfully prepared by solution impregnation method and self reinforcing concept. The PVA composite film prepared in this paper has good light transmittance, and the light transmittance is more than 85% at the wavelength of 400-800 nm. Compared with pure PVA films, the strength and toughness of random PVA nanofiber reinforced composites (R-PVAF) (30 wt%) and oriented PVA nanofiber reinforced composites (U-PVAF-1) (30 wt%) were both improved. Compared with R-PVA fiber, the strength and toughness of PVA composites can be further improved with the introduction of U-PVA fiber. The tensile strength of pure PVA film is about 30.1 MPa, while the tensile strength of U-PVAF-3 (50 wt%) can reach 70.0 MPa after the self-strengthening of PVA nanofiber, and the tensile strength of U-PVAF-3 (50 wt%) is increased by about 132.6%, indicating that the self-strengthening method can greatly improve the mechanical properties of PVA film.

MATERIALS FOR HUMANITY (MH 21)

Tensile properties of PVA nanofiber self-reinforced transparent PVA composite film

Welcome Seabirders!  

Welcome to Virtual World Seabird Conference 3 - vWSC3! Whether you are in your office or lab, at home, in a coffee shop or bar poaching some wifi, or at a remote field site or research vessel – we are very excited to welcome you to the third ever World Seabird Conference. 

We would like to thank ALL of you for being so patient as WSC3 was scheduled, postponed, rescheduled, revised to virtual, and scheduled again. Throughout all those iterations there was one message that remained perfectly clear – seabirders were eager to meet and share their science. If we could not meet in person then virtual it would have to be, but a 3rd WSC was something everyone wanted. That support and commitment helped the WSU Board of Directors and Member Societies sort through all of the challenges they faced to plan and hold this conference. 

The list of those that need to be thanked is long and, while we plan on recognizing many during the live closing plenary, it is important to do so here in writing as well. 

The Australasian Seabird Group was our Local Host for our plan to meet in Hobart, Tasmania. They invested substantial time and effort to find venues and plan events that we unfortunately were not able to visit. Nonetheless we appreciate their work on behalf of WSC3 and encourage all of you to thank them when you see their members in Gathertown or elsewhere during our virtual meeting. Their willingness to host created the initial excitement for WSC3 and without that our vWSC would not have been possible.

We also wish to thank the Science Program Committee, the Virtual Committee, and the Early Career Scientist Committee for their hard work planning the logistics, events, and schedule for vWSC3. These committees also had to deal with changing parameters and short timelines that made what is always a challenging task even more challenging. The Travel Awards Committee also invested time and effort in developing procedures for awarding travel funds that ultimately would not be implemented. 

Our ability to shift from an in-person to a virtual meeting, and to do so in a way that would be financially feasible, was due to the effective efforts of The International Fundraising Committee and to our financial sponsors. The IFC raised funds to support WSC3 and then, through the good relationships they built with sponsors, ensured we could re-envision how those funds could be used to support a virtual conference that would be affordable and high-quality.

We all owe the WSU Board of Directors and the Representatives of the Member Societies a great deal of thanks. They are the ones who manage the WSU and, for the past 18 months, have had to have a series of challenging meetings and conversations, have had to make a series of difficult choices, have had to do all of that while considering the short- and long-term health of WSU and the World Seabird Conferences, and did this while also managing their own challenges at their day jobs. We are grateful for their diligence, patience, foresight, and throughout all of the meetings, their collegiality. Also – a 6-year term is quite a commitment!

There would not be a WSC3 without a successful WSC1 and WSC2. Thanks go to the Pacific Seabird Group for their support of WSC1 in Victoria, Canada, and to the African Seabird Group for their support of WSC2 in Cape Town, South Africa. In each of these endeavors and for our current conference we were fortunate to work with a dependable and trustworthy partner in Podium Conferences. Michelle Smith and Marischal de Armond have become valued members of our team and have not only helped us plan conferences but have assisted and advised the WSU Chairs and Board on issues above and beyond conference planning. 

As we embark on our vWSC3 week we extend to all of you our thanks for showing up, for being patient, and most importantly for the work you do with seabirds. We are all part of a unique, global community that shares an interest, a fascination, and a passion for birds that make a living in our world’s oceans. We have advanced the science, conservation, and management of seabirds as well the ecosystems they inhabit. We are consistently impressed and motivated by the work you do. 

The WSU formed in 2010 because we saw the need for a global organization to address challenges at a global level. Over the past 11 years WSU has grown, adapted, and evolved to become the community that this week is making vWSC3 a reality. Enjoy the week, appreciate and support the friends and colleagues you have made in the community, and if you see us in a virtual hallway please stop and say hello! 

Thank you for the opportunity to serve all of you and the WSU over the past few years,

Nicholas Carlile, Interim Chair, WSU<br>
Patrick Jodice, 2nd Chair of the WSU<br><br>

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3rd World Seabird Conference

Join us for four days of science, networking and virtual engagement with delegates from around the world!

poster

**Please view our Welcome to MH21 video.**

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**Walkthrough Video**

Here is a Walkthrough showing how to navigate the conference and network with others 

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	  <iframe src="https://screencast-o-matic.com/watch/cr1vnrV1paE?v=6&ff=1&title=0&controls=1" width=826 height=526  frameborder="0" allowfullscreen="true"> </iframe>
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<p align="center" 
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	 <font color="#5eb1bf"  size="6"><b>Organized by</font>
<br>
<p align="center"><a href="https://mrs.org.sg/">
<img src="https://assets.underline.io/uploads/markdown_image/1/image/95d5789689d5f900b90e9fe54ea3cf0d.jpg"</a>
</p>
<br>
	<p align="center" 
	 </p>
	 <font color="#5eb1bf"  size="6"><b>In association with</font>
<br>
<p align="center"><a href="http://www.ntu.edu.sg/">
<img src="https://assets.underline.io/uploads/markdown_image/1/image/334cd171ad2fdee033c635b368e5e160.png"</a>
	<a href="https://www.nus.edu.sg/">
<img src="https://assets.underline.io/uploads/markdown_image/1/image/32e6f82c0440f7bb24c590f9f67821bd.png"</a>
		<a href="https://www.a-star.edu.sg/">
<img src="https://assets.underline.io/uploads/markdown_image/1/image/72557865b589cfa3d2a0243ffce4a270.png"</a>
	</p>
<br>

<p align="center" 
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	 <font color="#5eb1bf"  size="6"><b>Supported by</font>
<br>
		 <p align="center"><a href="https://www.visitsingapore.com/mice/en/about-us/about-secb/">
<img src="https://assets.underline.io/uploads/markdown_image/1/image/6e679842ead62be522ba6a630b82d5c9.png"</a>

To access the MH 21 Conference, [please register](https://mh21.mrs.org.sg/event/da3f9651-429f-4763-81b2-ebd7311b6bc8/websitePage:206f7605-1731-41f9-8421-56d3890f398f)

MH 21 is arranged around 6 themes that focus attention on pressing needs that should be addressed to enhance the well-being of communities and provide a forum for presenting breakthrough discoveries.

The unique characteristics of perovskite nanocrystals (NCs) comprise excellent luminous emissions, flexibility, and remarkable optoelectronic properties. Unfortunately, the fatal drawbacks of perovskite NCs include poor stability and chemical and thermal degradation. Several studies have demonstrated that the stability of CsPbBr3 colloidal NCs could be improved through the room temperature ligand-assisted re-precipitation (LARP) method. Additionally, analysis towards CsPbBr3 NCs surface will aid in developing long-term stability of colloidal NCs based devices. To date, no comprehensive study on the surface chemistry of CsPbBr3 colloidal NCs has been attempted nor initiated.

The Surface Structure of Size-tuneable Colloidal CsPbBr3 Nanocrystals

1) A new technique for synthesis of Au nanoparticle embedded inPoly(methyl-methacrylate-PMMA) and Poly(styrene - PS) freestanding (FS) films using biomimetic templates of black plum andlemon grass leaves is introduced. 2) The black plum leaf is hydrophilic while lemongrass ishydrophobic in nature. 3) The demonstration of these microstructurally replicated surfacesfor Surface enhanced Raman scattering (SERS) and wettabilityapplications is presented. 4) The wettability of the FS films is mainly hydrophilic with angledependent on surface roughness and precursor concentration.5) Detection of 4- aminothiophenol (4-ATP), L-Aspartic Acid andChebulinic acid by the FS films using is demonstrated. Enhancementfactors of the order of 104 are achieved.

Biomimetic-templated growth of gold nanoparticle-Poly(methyl-methacrylate) and Poly(styrene) films for different applications

The future of green electronics possessing great strength and toughness proves to be a promising area of research in this technologically advanced society. This work developed the first fully bendable and malleable toughened PLA green composite by incorporating a multi-functional PHB-rubber copolymer filler that acts as an effective nucleating agent to accelerate the PLA crystallization and performs as a dynamic plasticizer to generate massive polymer chain movement. The resultant biocomposite exhibits a 24-fold and 15-fold increment in both elongation and toughness respectively while retaining its elastic modulus at > 3 GPa. Mechanism study shows the toughening effect is due to an amalgamation of massive shear yielding, crazing, and nano-cavitation in the highly-dense PLA matrix. Uniquely distinguished from the typical flexible polymer that stretches and recovers, this biocomposite is the first report of PLA that can be “bend, twist, turn and fold” at room temperature and exhibit excellent mechanical robustness even after a 180 ° bend, attributes to the highly interconnected polymer network of innumerable nano-cavitation complemented with an extensively unified fibrillar bridges. This unique trait certainly opens up a new horizon to future sustainable green electronics development.

Bend, Twist and Turn: First Bendable and Malleable Toughened PLA Green Composites

Motivation: 1) Greater moisture stability of 2D and quasi-2D layered perovskites than 3D perovskites 2) Reduced phase impurity with control of composition of quasi-2D perovskites for improved optical properties and their application to optoelectronics devices 3) Double hole injection layer for reduced leakage current in optoelectronics device

Optimization of Composition with Reduced Phase Impurity in Quasi-2D Perovskite for Optoelectronics

Magnetic skyrmions are nanoscale spin structures which can be stabilized at room temperature in multilayer films [1, 2]. In particular, the amorphous multilayer film presents a pinning-free material platform, enabling efficient spin-orbit-torque manipulation of skyrmion dynamics. The device-relevant configuration of dots is of immense interest for realizing skyrmionic tunnel junctions for next-generation memory and computing applications [3]. Here, we first establish an amorphous multilayer composite stack comprising [Pt/CoB(x)/Ir]3/[Pt/CoB(y)/MgO], where x: 1.7-2.2 nm and y: 1-1.4 nm, with demonstrable skyrmions of sizes ~100 nm stabilized at zero field (ZF). By varying both the bottom (x) and top (y) CoB thicknesses, the magnetic anisotropy, Keff, can be tuned by an order from -0.03 to 0.126 MJ/m3. Next, we present ZF stabilization of skyrmions confined in such multilayer nanodots over a range of Keff and geometric sizes (w: 300 – 1000nm). Kerr magnetometry characterization of these nanodot arrays shows a monotonic increase in squareness with decreasing w. Expectedly, at ZF, we observe a gradual evolution in magnetic textures from the labyrinthine stripe to skyrmion phase, and eventually to the uniform magnetisation phase with w reduction (Figure 1). Notably, the stabilization of ZF skyrmions is observed over a wide w range from 400 to 700 nm across samples and skyrmion multiplets are stabilized in dots with low Keff. Finally, we demonstrate that at intermediate OP applied fields, skyrmion multiplets can be stabilized across varying w. Micromagnetic simulations are performed to model the geometric confinement effect of the nanodots on the skyrmion nucleation probability and size. These results provide a platform for harnessing the properties of nanoscale skyrmions in confined geometries for device applications.

Study of Confinement Effects on Skyrmions in Amorphous Multilayer Nanodots

Emulating advanced synaptic functions of the human brain with electronic devices contributes an important step toward constructing high-efficiency neuromorphic systems. Ferroelectric materials are promising candidates as synaptic weight elements in neural network hardware due to their controllable polarization states. However, the increased depolarization field at the nanoscale and the complex fabrication process of the traditional ferroelectric materials hamper the development of high-density, low power and highly sensitive synaptic devices. Here we report the implementation of 2D ferroelectrics α-In2Se3 as an active channel material to emulate typical synaptic functions. The α-In2Se3-based synaptic device features multi-mode operations, enabled by the coupled ferroelectric polarization under various voltage pulses applied at both drain- and gate-terminals. Moreover, the energy consumption can be reduced to ~ 1 pJ by using high-κ dielectric (Al2O3). The successful control of ferroelectric polarizations in α-In2Se3 and its application in artificial synapses are expected to inspire the implementation of 2D ferroelectric materials for future neuromorphic systems. （Acknowledgment: This work was supported by the Science and Engineering Research Council of A*STAR (Agency for Science, Technology and Research) Singapore, under Grant No. A20G9b0135.

Intrinsic Polarization Coupling in 2D α-In2Se3 toward Artificial Synapse with Multi-mode Operations

Two-dimensional (2D) van der Waals heterostructure (vdWH)-based floating gate devices show great potential for next-generation nonvolatile and multilevel data storage memory. However, high program voltage induced substantial energy consumption, which is one of the primary concerns, hinders their applications in low-en- ergy-consumption artificial synapses for neuromorphic computing. In this study, we demonstrate a three-terminal floating gate device based on the vdWH of tin disul- fide (SnS2), hexagonal boron nitride (h-BN), and few-layer graphene. The large electron affinity of SnS2 facilitates a significant reduction in the program voltage of the device by lowering the hole-injection barrier across h-BN. Our floating gate device, as a nonvolatile multilevel electronic memory, exhibits large on/off current ratio (~10 ), good retention (over 10 s), and robust endurance (over 1000 cycles). Moreover, it can function as an artificial synapse to emulate basic synaptic func- tions. Further, low energy consumption down to ~7 picojoule (pJ) can be achieved owing to the small program voltage. High linearity (<1) and conductance ratio (~80) in long-term potentiation and depression (LTP/LTD) further contribute to the high pattern recognition accuracy (~90%) in artificial neural network simulation. The proposed device with attentive band engineering can promote the future development of energy-efficient memory and neuromorphic devices.

Band-tailored van der Waals heterostructure for multilevel memory and artificial synapse

To sense is the ability to extract crucial information from the environment. However, the environment is dynamic, light levels during the day differ from the night. While current photodetectors show high sensitivity towards light stimuli, their dynamic range is limited by the ambient conditions. Fundamentally, they are unable to adapt chemically as well as our eyes. Here, a MoO3 - based electrochromic photodetector is demonstrated to sense with 2 adaptation modes – photopic and scotopic vision. The adjustment of sensitivity in demand depending on the requirement paves the way for environmentally adaptable devices.

Artificial eye that adapts to the environment - electrochromic photodetector

The association of sensory stimuli in the environment forms the basis of learning. Classical conditioning is a key benchmark of associative learning capabilities. While classical conditioning had been emulated in synaptic devices, the suppression of conditioning is yet to be explored. Here we emulate such inhibitory behaviour with an associatively coupled optoelectronic synapse which demonstrates altered plasticity behaviour. Such adaptable synapses are crucial building blocks in neuromorphic circuits capable of learning.

Emulating latent inhibition effects in the conditioning paradigm with an optoelectronic artificial synapse

We experimentally study the spin–orbit torque (SOT) in PtRh/heterostructures by varying the composition of PtRh alloy. By performing dc-biased spin-torque ferromagnetic resonance and second-harmonic measurements in PtxRh1−x/ferromagnet heterostructures, we find that the effective damping-like spin-torque efficiency and spin Hall conductivity are 0.18 and 3.8 × 105̵ h/2e Ω−1 m−1 for Pt0.9Rh0.1, respectively, with a low resistivity of 46.9 μΩ cm. Furthermore, current induced SOT switching in PtRh/Co is investigated. The critical current density for SOT switching decreases with an increase in the Rh composition of the PtRh alloy, which can be understood by domain wall assisted switching. Due to a large spin Hall conductivity, a relatively low resistivity, and sustainability of the high temperature process, the PtRh alloy could be an attractive spin source for SOT applications. Ref: 1. APL Mater. 9, 041105 (2021).

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The Surface Structure of Size-tuneable Colloidal CsPbBr3 Nanocrystals

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