9 research outputs found
Spotlight on 3-K For All: New York Citys 3-K for All Supports Mothers Labor Force Participation
New York City's 3-K for All program was first introduced to a few districts beginning in 2017 and was gradually made available to all districts by 2021. The rollout prioritized the highest-need districts for prekindergarten services. This report focuses on the role of New York City's 3-K in supporting mothers' labor force participation and employment.Using data from the Early Childhood Poverty Tracker, which repeatedly surveyed the same New York City families with young children from 2017 to 2021, the report investigates whether 3-K availability was associated with increased labor force participation and employment among mothers of preschool-age children in New York City
Spotlight on Early Childhood Education: Participation in Pre-K before and during the COVID-19 pandemic
The earliest educational experiences of children's lives are critical for their development and lay the foundation for their future achievement and well-being. For children from families facing socioeconomic disadvantage, high-quality public preschool (typically referred to as pre-K) is particularly important because of its potential to close educational opportunity gaps. Early childhood programs like preschool are also beneficial for parents because they allow parents to work or pursue education, while ensuring that children are well cared for in an enriching environment.Families in New York City are attuned to the importance of early education in large part due to the emphasis that the city has placed on its full-day universal pre-K program, known as Pre-K for All for four-year-old children. Pre-K for All is one of the largest pre-K programs in the country, serving an average of 70,000 children annually (about 65% of all New York City four-year-olds) prior to 2020. The COVID-19 pandemic tremendously disrupted New Yorkers' lives, and early education programs (including pre-K for All programs) faced difficult challenges during the height of the pandemic and in its wake. The Poverty Tracker surveyed families and their participation in Pre-K programs before and during the COVID-19 pandemic
Spotlight on Early Childhood Education: Participation in New York Citys 3-K for All program
Universal pre-kindergarten programsāstate-funded early childhood care and education programs that provide free preschool to children for one to two years before kindergartenāhave dramatically expanded across the United States over the past two decades. This expansion follows years of research showing that high quality preschool participation can reduce income-based school readiness gaps and promote children's cognitive and language development.New York City is a leader in the national universal pre-K effort with its citywide Pre-K for All program. The program launched in 2014 and quickly grew to offer free, full-day pre-K to all four-year-old children in 2015. New York City's universal pre-K programming expanded further in 2017 with 3-K for All, which aims to provide every three-year-old child in the city with free, full-day pre-K.In this report, we examine families' experiences with the 3-K for All program search, application, and enrollment process during the three academic years that began in fall 2018, 2019, and 2020, drawing from a representative sample of New York City families with young children surveyed by the Early Childhood Poverty Tracker
Improving Lithium-Metal Battery Performance under the Conditions of Lean Electrolyte through MoS2 Coating
Although lithium-metal-based batteries (LMBs) offer one of the highest energy densities, the issues with Li dendrite growths and the chemical reactivity between Li and electrolytes limit their applications. To enable a stable LMB under the practical conditions of lean electrolyte, thin Li metal and high mass loading, we introduce an efficient protective coating of MoS2 onto the Li-metal anode and analyzed its electrochemical performance under practical condition. The MoS2 coating successfully stabilizes the chemical activity of Li-metal surface by preventing dendrite growth and electrolyte dry-out, which results in the enhanced Li-metal battery cycle life by three-fold under the stringent conditions. Ā© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim1
In situ fabrication of a graphene-coated three-dimensional nickel oxide anode for high-capacity lithium-ion batteries
The high theoretical specific capacity of nickel oxide (NiO) makes it attractive as a high-efficiency electrode material for electrochemical energy storage. However, its application is limited due to its inferior electrochemical performance and complicated electrode fabrication process. Here, we developed an in situ fabrication of a graphene-coated, three-dimensional (3D) NiO-Ni structure by simple chemical vapor deposition (CVD). We synthesized NiO layers on Ni foam through a thermal oxidation process; subsequently, we grew graphene layers directly on the surface of NiO after a hydrogen-assisted reduction process. The uniform graphene coating renders high electrical conductivity, structural flexibility and high elastic modulus at atomic thickness. The graphene-coated 3D NiO-Ni structure delivered a high areal density of ā¼23 mg cm-2. It also exhibits a high areal capacity of 1.2 mA h cm-2 at 0.1 mA cm-2 for its Li-ion battery performance. The high capacity is attributed to the high surface area of the 3D structure and the unique properties of the graphene layers on the NiO anode. Since the entire process is carried out in one CVD system, the fabrication of such a graphene-coated 3D NiO-Ni anode is simple and scalable for practical applications. Ā© 2018 The Royal Society of Chemistry1
Synthesis of uniform single layer WS2 for tunable photoluminescence
Two-dimensional transition metal dichalcogenides (2D TMDs) have gained great interest due to their unique tunable bandgap as a function of the number of layers. Especially, single-layer tungsten disulfides (WS2) is a direct band gap semiconductor with a gap of 2.1 eV featuring strong photoluminescence and large exciton binding energy. Although synthesis of MoS2 and their layer dependent properties have been studied rigorously, little attention has been paid to the formation of single-layer WS2 and its layer dependent properties. Here we report the scalable synthesis of uniform single-layer WS2 film by a two-step chemical vapor deposition (CVD) method followed by a laser thinning process. The PL intensity increases six-fold, while the PL peak shifts from 1.92 eV to 1.97 eV during the laser thinning from few-layers to single-layer. We find from the analysis of exciton complexes that both a neutral exciton and a trion increases with decreasing WS2 film thickness; however, the neutral exciton is predominant in single-layer WS2. The binding energies of trion and biexciton for single-layer WS2 are experimentally characterized at 35 meV and 60 meV, respectively. The tunable optical properties by precise control of WS2 layers could empower a great deal of flexibility in designing atomically thin optoelectronic devices. Ā© The Author(s) 2017
Three-Dimensional Carbon Nanostructures for Advanced Lithium-Ion Batteries
This review contains the authors' recent progress on the design and fabrication of 3D carbon nanostructures, their performance in Li-ion batteries (LIBs), and their implementation into large-scale, lightweight, and flexible LIBs
Publisher Correction: 2D MoS2 as an efficient protective layer for lithium metal anodes in high-performance LiāS batteries
Spinful hinge states in the higher-order topological insulators WTe2
The standard topological insulator is characterized by an insulating bulk and a conducting boundary, so a three dimensional insulating bulk of a topological insulator has a conducting surface. Recently, this idea was extended to the edges of the surfaces of the three dimensional material as a new topological phase, referred to as a higher-order topological insulator. Here, the authors find evidence of such higher order topological insulator states in tungsten ditelluride using heterostructures composed of tungsten ditelluride and graphene