Dynamic Material Research Articles

Ion‐Specific Interactions Engender Dynamic and Tailorable Properties in Biomimetic Cationic Polyelectrolytes

AbstractBiomaterials such as spider silk and mussel byssi are fabricated by the dynamic manipulation of intra‐ and intermolecular biopolymer interactions. Organisms modulate solution parameters, such as pH and ion co‐solute concentration, to effect these processes. These biofabrication schemes provide a conceptual framework to develop new dynamic and responsive abiotic soft material systems. Towards these ends, the chemical diversity of readily available ionic compounds offers a broad palette to manipulate the physicochemical properties of polyelectrolytes via ion‐specific interactions. In this study, we show for the first time that the ion‐specific interactions of biomimetic polyelectrolytes engenders a variety of phase separation behaviors, creating dynamic thermal‐ and ion‐responsive soft matter that exhibits a spectrum of physical properties, spanning viscous fluids to viscoelastic and viscoplastic solids. These ion‐dependent characteristics are further rendered general by the merger of lysine and phenylalanine into a single, amphiphilic vinyl monomer. The unprecedented breadth, precision, and dynamicity in the reported ion‐dependent phase behaviors thus introduce a broad array of opportunities for the future development of responsive soft matter; properties that are poised to drive developments in critical areas such as chemical sensing, soft robotics, and additive manufacturing.

Methodology for material flow analysis at the organizational scale

Organizations play a crucial role in facilitating the transition to a circular economy. Implementing circular practices often begins with a material flow analysis (MFA) to identify issues and opportunities. However, existing MFA methodologies focus mainly on territorial applications and lack effectiveness at the organizational level. Conducting MFA at this level presents distinct challenges, requiring insights into dynamic material circulation and effective handling of heterogeneous data. Addressing this gap, this study introduces an innovative methodology tailored to organizational contexts. The developed methodology consists of six steps for conducting MFA while proposing an archetype-based approach capable of analyzing extensive and disparate datasets, coupled with bootstrapping and Monte Carlo simulation techniques, that considerably reduces the complexity of MFA execution. Furthermore, this methodology enables a comprehensive understanding of material flows within the system and provides a straightforward method for estimating uncertainty in mass estimations by incorporating confidence level calculations. A case study from a governmental organization is used to illustrate the proposed methodology.

Local structural behaviour of the outer containment of an NPP against hard missile impact

An aircraft crash and missile impact on a nuclear containment structure is currently described as an event beyond design basis; however, soon, it will be qualified as a primary design criterion. In the present study, the structural and dynamic behaviour of the outer containment of a nuclear power plant (NPP) has been studied to substantiate its structural integrity against the rigid missile impact. Scaled experiments (at a 1:4 and 1:3 ratio with respect to shell thickness) have been performed to study the localized behaviour of the containment structure against 10 and 20-kg rigid steel projectiles. The reinforced cement concrete (RCC) targets of thicknesses 150 and 200 mm have been subjected to impact at incidence velocity close to the landing and taking of velocity of the aircraft. The flexural reinforcement ratio was considered 1.25 % for a 150 mm thick target and 1.53 % for a 200 mm thick target. The effect of shear reinforcement on the penetration and perforation resistance has been studied for a 200 mm thick RCC target. A detailed post-test examination was conducted to evaluate the localized physical damage characteristics such as spalling and scabbing of concrete, penetration, perforation, crack propagation, and the damage induced in both flexural and shear reinforcements. The mechanics of deformation and failure modes of the target were investigated under varying incidence velocities, 60–115 m/s. The reinforcement characteristics under dynamic loading, such as strain time histories, strain rate sensitivity, and dynamic material properties, were also investigated. The presence of transverse reinforcement in 200 mm thick targets improved the ballistic performance by 12.50 %. Furthermore, the transverse reinforcement also played a crucial role in restricting the bending of the rear face flexural reinforcement and controlling the rear face damage propagation.

Infrastructure Transitions in Southern Cities: Organising Urban Service Delivery for Climate and Development

Rapidly growing cities in the Global South are characterised by high levels of vulnerability and informality and are expected to bear a disproportionate share of the costs of a changing climate. The confluence of climate change impacts, inequitable urbanisation processes, and under-development emphasise the need for accelerated urban transitions in Southern cities, yet mainstream theories of urban sustainability transitions have been shown to be insufficient for such contexts. This is particularly relevant with regard to urban infrastructure: While mainstream urban theory tends to regard infrastructure as static, centralised, and heavily engineered, infrastructure configurations in cities of the Global South are often heterogeneous, comprising multiple dynamic social and material flows. Drawing on theory from Southern Urbanism and empirical data of unorthodox infrastructures from 14 cities, this article assesses the potential challenges posed by applying a key transitions framework—namely the Multi-Level Perspective—in Southern contexts. The article closes by suggesting a set of theoretical propositions for future conceptual and empirical research that could advance transitions literature more broadly, and highlights the need for all cities to pursue inclusive service delivery models that are responsive to the complex and shifting landscape of climate impacts.

Clustering of biphenyl oxamide ions by chiral recognition.

Gels created by self-assembly of small organic molecules are dynamic soft materials that have unique properties and demanding characterization. Four chiral gelators, with two valinol- or leucinoloxamido arms attached to the 2,2'-positions of the proatropisomeric biphenyl group were chosen to show that the electrospray ionization mass spectrometry (ESI-MS) could be used to differentiate the gelation feature of the chiral compounds 1-4 and also to shed light on the gelation processes. By inspecting the gelation of several solvents, we showed that 1 (R, R) proved to be the most efficient gelator, forming the largest observable assemblies in the gas phase. The strong intermolecular H-bonds hold single-charged assemblies consisting of up to five monomer units detectable by ESI MS. Enantiomer 1 (R, R) is a good gelator due to favorable intramolecular interactions that remain preserved in the gas phase. Compound 3 (meso) does not have gelator properties and detected signals of larger assemblies in the gas phase. So, the detected signals correlate with the conformations of the studied compounds. MS could be used to elucidate the preferential type of noncovalent interaction due to the chiral recognition. The study paves a novel way to investigate the influence of chirality on the molecular assembly and consequently macroscopic properties and functions of materials.

SCIENTIFIC REASONING ABILITY OF CLASS XI STUDENTS OF SMA NEGERI 1 SINDUE TOMBUSABORA ON DYNAMIC FLUID MATTER

The purpose of this research is to determine the scientific reasoning abilities of students of state high school 1Sindue Tombusabora on dynamic fluid material. This type of research is qualitative research. The research respondents were 15 students out of 20 class XI Mathematics and Science 2 students at state high school 1 Sindue Tombusabora for the 2022/2023 academic year. The technique for taking respondents in this study used a purposive sampling area. The results of this study indicate that students' scientific reasoning on dynamic fluid material is still relatively low. This is evidenced by the category that students get the most in each scientific reasoning. In the pattern of correlation reasoning, students are in the No relationship (NR) category where most students are at (level 2) of the maximum (level 4) which means that students' correlation reasoning abilities to connect two problems or causation are still low. Then in the proportional reasoning pattern, most students are in the TM (no answer) category, where students do not answer questions, which means students empty answers (level 0). This means that the ability of students to provide answers to problems involving comparisons is still low.

Engineering Supramolecular Hydrogels via Reversible Photoswitching of Cucurbit[8]uril-Spiropyran Complexation Stoichiometry.

The integration of photoswitchable supramolecular units into hydrogels allows for spatiotemporal control over their nanoscale topological network and macroscale properties using light. Nevertheless, the current availability of photoswitchable supramolecular interactions for the development of such materials remains limited. Here, the molecular design of a novel photoswitchable cucurbit[8]uril-spiropyran host-guest complex exhibiting fast and reversible switching of binding ratios between 1:2 and 1:1 is reported. Photoswitchable complexation stoichiometries are rationally exploited as (de)crosslinking units in multiple polymers for the design of supramolecular hydrogels displaying highly dynamic and switchable features that are spatiotemporally controlled by light. The hydrogels exhibit rapid reversible mechanical softening-hardening upon alternating irradiation with blue and UV light, which is used to significantly accelerate and improve the efficiency of self-healing and shape-remolding of hydrogels. Furthermore, spiropyran endows such materials with unique reversible photochromic properties for reproducible patterning/erasing and information storage. Using a dual-light-assisted extrusion process, meter-scale hydrogel fibers with enhanced structural integrity and photoswitchable ionic conductivity are constructed and woven into various slidable knots and fluorescent shapes. This work represents an innovative molecular design strategy for advancing the development of spatiotemporally engineered supramolecular hydrogels using light and opens avenues for their prospective applications in dynamic materials and adaptive systems.

Re-conceptualizing climate maladaptation: Complementing social-ecological interactions with relational socionatures

Cases of climate maladaptation are increasingly documented. Its identification and redressal has become a priority for researchers and policymakers concerned with climate vulnerability reduction. The ability to address climate maladaptation hinges on being open to its diverse causes, manifestations, and impacts. This study argues that climate maladaptation analyses are dominated by an “interactional ontology”—the understanding that it can be explained as an observable outcome from how separate social, economic, and political systems interact in moments of time. Consequently, efforts to curb climate maladaptation often target the institutional contexts (e.g., rules, regulations) understood as enabling adaptation practices to aggravate climate risks. But this only captures a partial aspect of climate maladaptation, neglecting underlying causes and processes. We argue a “relational ontology” can complement the “why and how” of maladaptation. A relational ontology understands climate maladaptation as an evolving process constituted through dynamic material and discursive relations, versus an observable outcome from separately interacting systems. By analyzing how adaptation initiatives are related to, framed, and politicized, assembly processes are rendered visible. To demonstrate this, we study the Government of Maharashtra’s (India) Jalyukt Shivar Abhiyan, a program aimed at increasing water conservation to “free” 20,000 villages from drought impacts. From our theorization and empirical case, we discuss how a relational ontology contributes to debates in the climate maladaptation literature and invites approaches for mitigating this phenomenon.

Novel multi-mode anti-counterfeiting encryption material of CaAl12O19:Eu, Er with multi-color down-conversion luminescence, up-conversion luminescence, dynamic luminescence, and photochromism

Multi-mode dynamic anti-counterfeiting materials can provide complex anti-counterfeiting performance and ensure the anti-counterfeiting strategy becomes more secure. Herein, a new type of multi-mode anti-counterfeiting encryption material of CaAl12O19:Eu, Er with different Er doping concentration was developed by sol–gel method. Interestingly, the CaAl12O19:Eu, Er phosphor and its composite have multi-mode anti-counterfeiting characteristics of multi-color down-conversion luminescence, up-conversion luminescence, dynamic luminescence, and photochromism. Effect of different Er doping concentration on the down-conversion luminescence, up-conversion luminescence, dynamic luminescence, and photochromism of CaAl12O19:Eu, Er was systematically investigated, and the relevant mechanisms were discussed. These anti-counterfeiting features can be simultaneously applied in both bright and dark fields, which can achieve high-level anti-counterfeiting in both spatial and temporal dimensions. The CaAl12O19:Eu, Er phosphors cannot be easily replaced by other materials with the same anti-counterfeiting properties. They display good application foreground in the field of anti-counterfeiting encryption.

THE INFLUENCE OF DIGITAL LITERACY ON STUDENTS PROBLEM SOLVING ABILITY IN PHYSICS SUBJECTS

This research aims to measure the effect of digital literacy on students' problem solving abilities in physics subjects which are limited to class XI dynamic fluid material. This research uses quantitative methods with a causal associative research design. The sample for this research was 74 students obtained from the sampling technique, namely purposive sampling. The research instruments used in this study were a questionnaire sheet for the digital literacy variable and a question sheet for the problem solving ability variable. The data analysis technique that will be carried out is inferential statistical analysis using simple linear regression hypothesis testing. The results of this study show a significance value of 0.00, which means it is smaller than 0.05, so there is an influence between digital literacy and students' problem solving abilities. However, this research has limitations, namely it only focuses on measuring the influence and only on dynamic fluid materials.

Supplemental Material for Dynamics Between Affect and Social Acceptance as a Function of Social Anxiety: A Person-Specific Network Approach

Supplemental Material for Dynamics Between Affect and Social Acceptance as a Function of Social Anxiety: A Person-Specific Network Approach

Photochromic Spiropyran-Based Dual-Emitting Luminescent Hybrid Films for Dynamic Information Anticounterfeiting.

Photoluminescent materials are widely used for information storage and anticounterfeiting, while most of them have the disadvantages of static information performance and weak processability, which is still a challenging task in developing dynamic anticounterfeiting materials with high security levels. Herein, we fabricated a novel photostimuli-responsive dual-emitting luminescent material UPTES-SPn-Tb-hfa, which was obtained by introducing the photochromic molecule spiropyran (SP) and lanthanide complex (Tb-hfa) into a siloxane-polyether matrix using the sol-gel process. Due to the conformation-dependent photochromic fluorescence resonance energy transfer between the Tb-hfa donor and SP acceptor, the ring-closing (SP)/ring-opening (MC) isomerization of the SP unit leads to a reversible luminescence switching in UPTES-SPn-Tb-hfa. This composite material has great potential for advanced anticounterfeiting because of the advantage of rapidly repeatable encryption/decryption for at least 8 times and dynamic luminescent colors within 15 s. In addition, due to its two luminescent centers (Tb3+ and MC), the luminescent color of this material can be regulated by 254 and 365 nm UV-light irradiation, which facilitates the design of multicolored anticounterfeiting labels. Our work presents a novel design methodology to fabricate dynamic anticounterfeiting materials, significantly enhancing the security of anticounterfeiting applications.

TPE-embedded butterfly bis-crown ether with controllable conformation and supramolecular chiroptical property

Understanding how subtle structural differences between macrocyclic conformational isomers impact their properties and separation has garnered increasing attention in the field of supramolecular synthetic chemistry. In this work, a series of tetraphenylene (TPE)-embedded butterfly bis-crown ether macrocycles (BCE[n], n = 4–7), comprising two crown ether side rings and a TPE core, are synthesized through intramolecular McMurry coupling. Unexpectedly, the presence of flexible oligoethylene chains with varying lengths are found to influence molecular conformation via multiple intramolecular interactions, resulting in the formation of two stabilized conformers with specific semi-rigid symmetric/asymmetric structures (sym-BCE[n] and asym-BCE[n], n = 5, 6). Moreover, it is noteworthy that neither symmetric nor asymmetric conformers are present in the more rigid BCE[4] or the more flexible BCE[7]. Interestingly, these conformers display distinct fluorescence properties and host-guest binding abilities, and only sym-BCE[5] can serve as a host for chiral polymer binding, resulting in the formation of chiral supramolecular assemblies through host-guest interaction induced chirality. Moreover, both circular dichroism and circularly polarized luminescence signals of the obtained assemblies can be switched off by the addition of sodium ion, suggesting potential applications in the field of dynamic chiral materials.

Efektivitas Penggunaan Model Pembelajaran Problem Based Learning Combine Teams Games Tournament Terhadap Keaktifan Dan Hasil Belajar Peserta Didik Fase E Sma Negeri 3 Surakarta Tahun Ajaran 2022/2023

<p><em>The purpose of this study was to (1) find out the differences in the learning activeness of students who were taught the problem-based learning combine team games tournament learning model with the problem-based learning learning model in geography learning material on lithosphere dynamics in phase E SMA Negeri 3 Surakarta and (2) find out the differences the learning outcomes of students who were taught the problem-based learning model combine teams games tournament with the problem-based learning model in learning geography on lithosphere dynamics material in phase E SMA Negeri 3 Surakarta. This research uses quasi-experimental research. The population of the study was the students of SMA Negeri 3 Surakarta phase E. The sampling technique was carried out by simple random sampling. Data collection techniques were carried out by observation and tests. The analysis technique used in this study used the t test (independent sample t-test) on learning activity and student learning outcomes. The results are as follows (1) there are differences in student learning activeness between the problem-based learning combine team games tournament learning model and the problem-based learning learning model with sig2 tailed results of 0.028 > 0.05. (2) there are differences in student learning outcomes between the problem-based learning combine team games tournament learning model and the problem-based learning model with sig2 tailed results of 0.042 > 0.05. The application of the problem based learning combine team games tournament learning model is better than the problem based learning learning model. </em></p><p><em>Keywords : </em><em>learning activities, learning outcomes, problem based learning combine teams games tournament</em></p>

Dynamic material flow analysis of construction materials in Saudi Arabia: Strategies for sustainability of residential buildings

Globally, the expansion of building infrastructure has serious environmental implications due to emissions from cement and steel. The construction industry uses the vast majority of cement and steel produced globally and locally. Consequently, this paper proposes a model to estimate and mitigate future material flow emissions into residential buildings in Saudi Arabia. First, a dynamic material flow model is used to quantify material flows and stock in residential buildings. The evolution of Saudi housing stock and related steel and cement are simulated from 1950 to 2100. Second, various strategies such as material efficiency improvement, lifetime extension, and reducing production emissions are simulated to reduce emissions caused by cement and steel. The findings indicate that implementing substantial material efficiency improvements can result in 33 %–46 % reductions of cumulative steel and cement emissions from 2023 to 2100, respectively. Furthermore, improving material efficiency measures could result in over 80 % reductions in emissions for steel over the same period. Reducing the ratio of clinker to supplementary cementitious materials in cement to 75 % could reduce cumulative cement emissions by 129 million tCO2e (17 %). Adoption of high material efficiency practices in cement use, low clinker cement, and waste as fuel can reduce emissions by 70 %. The findings of this study contribute to a better understanding of future emissions from building materials used in residential buildings, as well as the impact of emission mitigation strategies on future emissions, which will help decision-makers and researchers develop policies and research.

Ultra-Fast Selenol-Yne Click (SYC) Reaction Enables Poly(selenoacetal) Covalent Adaptable Network Formation.

The emergence of covalent adaptable networks (CANs) based on dynamic covalent bonds (DCBs) presents a promising avenue for achieving resource recovery and utilization. In this study, we discovered a dynamic covalent bond called selenacetal, which is obtained through a double click reaction between selenol and activated alkynes. Density functional theory (DFT) calculations demonstrated that the ΔG for the formation of selenoacetals ranges from 12 to 18 kJ mol-1, suggesting its potential for dynamic reversibility. Dynamic exchange experiments involving small molecules and polymers provide substantial evidence supporting the dynamic exchange properties of selenoacetals. By utilizing this highly efficient click reaction, we successfully synthesized dynamic materials based on selenoacetal with remarkable reprocessing capabilities without any catalysts. These materials exhibit chemical recycling under alkaline conditions, wherein selenoacetal (SA) can decompose into active enone selenide (ES) and diselenides. Reintroducing selenol initiates a renewed reaction with the enone selenide, facilitating material recycling and yielding a newly developed dynamic material exhibiting both photo- and thermal responsiveness. The results underscore the potential of selenoacetal polymers in terms of recyclability and selective degradation, making them a valuable addition to conventional covalent adaptable networks.

Ultra‐Fast Selenol‐Yne Click (SYC) Reaction Enables Poly(selenoacetal) Covalent Adaptable Network Formation

AbstractThe emergence of covalent adaptable networks (CANs) based on dynamic covalent bonds (DCBs) presents a promising avenue for achieving resource recovery and utilization. In this study, we discovered a dynamic covalent bond called selenacetal, which is obtained through a double click reaction between selenol and activated alkynes. Density functional theory (DFT) calculations demonstrated that the ΔG for the formation of selenoacetals ranges from 12 to 18 kJ mol−1, suggesting its potential for dynamic reversibility. Dynamic exchange experiments involving small molecules and polymers provide substantial evidence supporting the dynamic exchange properties of selenoacetals. By utilizing this highly efficient click reaction, we successfully synthesized dynamic materials based on selenoacetal with remarkable reprocessing capabilities without any catalysts. These materials exhibit chemical recycling under alkaline conditions, wherein selenoacetal (SA) can decompose into active enone selenide (ES) and diselenides. Reintroducing selenol initiates a renewed reaction with the enone selenide, facilitating material recycling and yielding a newly developed dynamic material exhibiting both photo‐ and thermal responsiveness. The results underscore the potential of selenoacetal polymers in terms of recyclability and selective degradation, making them a valuable addition to conventional covalent adaptable networks.

Photocurable vitrimers with malleable and self-healing trade-off enabled by manipulating dynamic boronic ester bonds

Although numerous strategies refer to dynamic covalent bond exchanges of small molecules for self-repairing thermosets, it remains a critical challenge to be able to jointly tune the malleability and dynamic properties of photocurable materials via extending dynamical small molecule bridging chains with tunable kinetic features. Herein, we successfully synthesized two typical diboronic ester molecules (diboronic ester dithiol/diacid) with variable dioxaborolane metathesis kinetics, which acted as dynamical interlinking segments constructing simple hydrogenated bisphenol A (HBA) epoxy backbone to achieve dynamically cross-linking feature. Subsequently, the acrylate- and anhydride-modified HBA vitrimers bearing diboronic ester-extending segment variants and photocuring traits are successfully synthesized by a one-pot reaction. Consequently, it is demonstrated that the embedded amounts of dynamic diboronic ester bonds in the backbone play a key role in the photopolymerization rate of photocurable vitrimers. The photopolymerization rate decreases significantly as more diboronic ester segments. Moreover, the diboronic ester dithiol-mediated photocurable vitrimer (HBA-S) exhibits enhanced malleability (strain at break of 26.6 %), desirable photo-crosslinked network, and accelerated thermal-triggered self-healing ability (scratch self-healing efficiency of closing to 100 % at 150 °C), compared to those of the diboronic ester diacid-mediated vitrimer (HBA-O) under identical conditions. This work validates the probability of transferring the dioxaborolane metathesis of small molecules to dynamic properties of bulk UV-curing materials, which provides valuable guidance for the rational design and fabrication of tunable dynamic photocurable materials.

Advancing Surface Engineering for Tribology: From Functionality to Connectivity

Surface functionality plays a pivotal role in Tribology, a discipline dedicated to examining the interactions of surfaces in relative motion. The approach, known as Tribotronics, combines Tribology and electronics, enabling active tribological components to be embedded in larger systems and networks constituting the Industrial Internet of Things. Leveraging novel technologies such as advanced sensing coatings and triboelectric nanogenerators, the sensing capability of Tribotronic systems undergoes a transformative shift from a device‐centric to a surface‐centric paradigm. This critical advancement unlocks the potential for direct interface probing and in‐situ measurement of tribological processes, marking a significant milestone in the field. This emerging trend introduces the concept of the Internet of Surfaces, a novel perspective within surface engineering. It entails the amalgamation of sensing capabilities, embedded power generation, and external analytics, creating dynamic materials in the context of Industry 4.0.

Nonequilibrium phases of a biomolecular condensate facilitated by enzyme activity.

Biomolecular condensates represent a frontier in cellular organization, existing as dynamic materials driven out of equilibrium by active cellular processes. Here we explore active mechanisms of condensate regulation by examining the interplay between DEAD-box helicase activity and RNA base-pairing interactions within ribonucleoprotein condensates. We demonstrate how the ATP-dependent activity of DEAD-box helicases-a key class of enzymes in condensate regulation-acts as a nonequilibrium driver of condensate properties through the continuous remodeling of RNA interactions. By combining the LAF-1 DEAD-box helicase with a designer RNA hairpin concatemer, we unveil a complex landscape of dynamic behaviors, including time-dependent alterations in RNA partitioning, evolving condensate morphologies, and shifting condensate dynamics. Importantly, we reveal an antagonistic relationship between RNA secondary structure and helicase activity which promotes condensate homogeneity via a nonequilibrium steady state. By elucidating these nonequilibrium mechanisms, we gain a deeper understanding of cellular organization and expand the potential for active synthetic condensate systems.