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Nano-black carbon (biochar) released from pyrogenic carbonaceous matter as a super suspending agent in water/soil environments
Nano-black carbon (BC) is one of the most active fractions in the pyrogenic carbonaceous matter continuum. The majority of recent studies mainly focus on the role of nano-BC in the global carbon cycle. However, based on literature and our recent studies, we suggest that nano-BC may also serve as a super suspending agent, carrier, and redox mediator for sorbates during its migration from terrestrial to water bodies due to its unique properties such as high colloidal stability, strong sorption capacity, and high surface reactivity. The full implications of nano-BC in water/soil environments are far more than we expected. Thus, we call for more detailed investigations on the activity and reactivity of nano-BC in water/soil environments
Dynamic aspiration based on Win-Stay-Lose-Learn rule in Spatial Prisoner's Dilemma Gam
Prisoner's dilemma game is the most commonly used model of spatial
evolutionary game which is considered as a paradigm to portray competition
among selfish individuals. In recent years, Win-Stay-Lose-Learn, a strategy
updating rule base on aspiration, has been proved to be an effective model to
promote cooperation in spatial prisoner's dilemma game, which leads aspiration
to receive lots of attention. But in many research the assumption that
individual's aspiration is fixed is inconsistent with recent results from
psychology. In this paper, according to Expected Value Theory and Achievement
Motivation Theory, we propose a dynamic aspiration model based on
Win-Stay-Lose-Learn rule in which individual's aspiration is inspired by its
payoff. It is found that dynamic aspiration has a significant impact on the
evolution process, and different initial aspirations lead to different results,
which are called Stable Coexistence under Low Aspiration, Dependent Coexistence
under Moderate aspiration and Defection Explosion under High Aspiration
respectively. Furthermore, a deep analysis is performed on the local structures
which cause cooperator's existence or defector's expansion, and the evolution
process for different parameters including strategy and aspiration. As a
result, the intrinsic structures leading to defectors' expansion and
cooperators' survival are achieved for different evolution process, which
provides a penetrating understanding of the evolution. Compared to fixed
aspiration model, dynamic aspiration introduces a more satisfactory explanation
on population evolution laws and can promote deeper comprehension for the
principle of prisoner's dilemma.Comment: 17 pages, 13 figure
Half-Heusler Compounds as a New Class of Three-Dimensional Topological Insulators
Using first-principles calculations within density functional theory, we
explore the feasibility of converting ternary half-Heusler compounds into a new
class of three-dimensional topological insulators (3DTI). We demonstrate that
the electronic structure of unstrained LaPtBi as a prototype system exhibits
distinct band-inversion feature. The 3DTI phase is realized by applying a
uniaxial strain along the [001] direction, which opens a bandgap while
preserving the inverted band order. A definitive proof of the strained LaPtBi
as a 3DTI is provided by directly calculating the topological Z2 invariants in
systems without inversion symmetry. We discuss the implications of the present
study to other half-Heusler compounds as 3DTI, which, together with the
magnetic and superconducting properties of these materials, may provide a rich
platform for novel quantum phenomena.Comment: 4 pages, 5 figures; Phys. Rev. Lett. (in press
Seasonal variation of phytoplankton community assembly processes in Tibetan Plateau floodplain
Uncovering the mechanisms underlying phytoplankton community assembly remains a major challenge in freshwater ecology. The roles of environmental filtering and spatial processes in shaping phytoplankton metacommunity in Tibetan floodplain ecosystems under various hydrological conditions are still unclear. Here, multivariate statistics and a null model approach were used to compare the spatiotemporal patterns and assembly processes of phytoplankton communities in the river-oxbow lake system of Tibetan Plateau floodplain between non-flood and flood periods. The results showed that phytoplankton communities had significant seasonal and habitat variations, with the seasonal variations being more remarkable. Phytoplankton density, biomass, and alpha diversity were distinctly lower in the flood than non-flood period. The habitat differences (rivers vs. oxbow lakes) in phytoplankton community were less pronounced during the flood than non-flood period, most likely due to the increased hydrological connectivity. There was a significant distance-decay relationship only in lotic phytoplankton communities, and such relationship was stronger in the non-flood than flood period. Variation partitioning and PER-SIMPER analysis showed that the relative role of environmental filtering and spatial processes affecting phytoplankton assemblages varied across hydrological periods, with environmental filtering dominating in the non-flood period and spatial processes in the flood period. These results suggest that the flow regime plays a key role in balancing environmental and spatial factors in shaping phytoplankton communities. This study contributes to a deeper understanding of ecological phenomena in highland floodplains and provides a theoretical basis for floodplain ecosystem maintenance and ecological health management.Peer reviewe
Let's Chat to Find the APIs: Connecting Human, LLM and Knowledge Graph through AI Chain
API recommendation methods have evolved from literal and semantic keyword
matching to query expansion and query clarification. The latest query
clarification method is knowledge graph (KG)-based, but limitations include
out-of-vocabulary (OOV) failures and rigid question templates. To address these
limitations, we propose a novel knowledge-guided query clarification approach
for API recommendation that leverages a large language model (LLM) guided by
KG. We utilize the LLM as a neural knowledge base to overcome OOV failures,
generating fluent and appropriate clarification questions and options. We also
leverage the structured API knowledge and entity relationships stored in the KG
to filter out noise, and transfer the optimal clarification path from KG to the
LLM, increasing the efficiency of the clarification process. Our approach is
designed as an AI chain that consists of five steps, each handled by a separate
LLM call, to improve accuracy, efficiency, and fluency for query clarification
in API recommendation. We verify the usefulness of each unit in our AI chain,
which all received high scores close to a perfect 5. When compared to the
baselines, our approach shows a significant improvement in MRR, with a maximum
increase of 63.9% higher when the query statement is covered in KG and 37.2%
when it is not. Ablation experiments reveal that the guidance of knowledge in
the KG and the knowledge-guided pathfinding strategy are crucial for our
approach's performance, resulting in a 19.0% and 22.2% increase in MAP,
respectively. Our approach demonstrates a way to bridge the gap between KG and
LLM, effectively compensating for the strengths and weaknesses of both.Comment: Accepted on ASE'202
A centimeter-scale achromatic hybrid metalens with polarization-insensitivity in the visible
Metalenses, featuring ultra-compactness and CMOS compatibility, are limited
by the compromise between the diameter, numerical aperture, and working
waveband. To address this problem, we propose and numerically demonstrate a
centimeter-scale metasurface-refractive hybrid metalens working in the band of
440 - 700 nm. Revisiting the general Snell law, we present the phase profile of
a chromatic aberration correction metasurface that can apply to a plano-convex
refractive lens of an arbitrary surface type. Simulated by our semi-vector
method, the designed achromatic hybrid metalens achieves 81% chromatic
aberration suppression and polarization insensitivity. Broadband imaging
results of the hybrid metalens are further provided, verifying the achromatism
of the designed hybrid metalens. It can find applications in camera lenses and
other optical systems that need compact, high-performance lenses.Comment: 10 pages, 5 figures
Aqueous intercalation-type electrode materials for grid-level energy storage: Beyond the limits of lithium and sodium
The final publication is available at Elsevier via http://dx.doi.org/10.1016/j.nanoen.2018.05.049 © 2018. This manuscript version is made available under the CC-BY-NC-ND 4.0 license http://creativecommons.org/licenses/by-nc-nd/4.0/Intermittent, fluctuational, and unpredictable features of renewable energy require grid-level energy storage (GES). Among various types of GES, aqueous electrochemical storage is undoubtedly the most promising method due to its high round-trip efficiency, long cycle life, low cost and high safety. As the most encouraging candidate for aqueous electrochemical storage, aqueous rocking-chair batteries have been heavily investigated. Recently, intercalation-type aqueous batteries beyond the limits of Li+ and Na+ have caught researchers’ attention due to potentially higher capacity and better cyclability, and the number of publications in this nascent field since 2015 has dramatically increased. Therefore, it is highly demanded to summarize what have been learned in this field. In this first comprehensive review paper, we summarize these novel intercalation-type electrode materials and provide perspectives of opportunities and challenges for future research.Natural Sciences and Engineering Research Council of Canada (NSERC)
Waterloo Institute for Nanotechnology
National Natural Science Foundation of China (51272182, 51772219, 21471116, and 51641210)
Zhejiang Provincial Natural Science Foundation of China (LZ17E020002 and LZ15E020002)
Wenzhou Scientific and Technological in Public Project (G20170018
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