Changes In State Research Articles

Surface effect on the partial-slip contact of a nano-sized flat indenter

The partial-slip contact at nano-scale is always influenced by a surface effect. A new model based on the Gurtin-Murdoch (G-M) surface elasticity theory is proposed in this paper to study the partial-slip contact behavior of a rigid flat nano-indenter on an elastic half-space. The surface effect in the partial-slip contact is characterized via a non-classical boundary condition involving a surface-induced normal traction related to the residual surface stress and a surface-induced tangential traction related to the surface elasticity, the influences of which on stress and displacement fields and the stick-slip state at the contact surface are investigated. It is found that, with the increase of residual surface stress, both the normal pressure and vertical and horizontal displacements in the contact zone decrease, the relative slip between indenter and substrate reduces and the stick region is enlarged. Such effects are basically attributed to the action of the surface-induced normal traction opposite to the externally applied compression. However, the increase of surface elastic constants is conductive to the relative slip and results in a shrinkage of the stick region, which is attributed to the action of the surface-induced tangential traction opposite to the frictional stress. An interesting phenomenon is further unveiled that, when the frictional coefficient increases, the dominant role in affecting the stick-slip state changes from the surface-induced tangential traction to the normal one, thus inspiring a feasible route to manipulate the surface effect by tuning the frictional coefficient of substrate. The present research enables one to better understand the partial-slip contact behavior of nano-indenters, which is of guiding value for anti-wear designs in nano-mechanical devices.

Effect of mPEG-PLGA on Drug Crystallinity and Release of Long-Acting Injection Microspheres: In Vitro and In Vivo Perspectives.

Traditional progesterone (PRG) injections require long-term administration, leading to poor patient compliance. The emergence of long-acting injectable microspheres extends the release period to several days or even months. However, these microspheres often face challenges such as burst release and incomplete drug release. This study aims to regulate drug release by altering the crystallinity of the drug during the release process from the microspheres. This research incorporates methoxy poly(ethylene glycol)-b-poly(lactide-co-glycolide) (mPEG-PLGA) into poly(lactide-co-glycolide) (PLGA) microspheres to enhance their hydrophilicity, thus regulating the release rate and drug morphology during release. This modification aims to address the issues of burst and incomplete release in traditional PLGA microspheres. PRG was used as the model drug. PRG/mPEG-PLGA/PLGA microspheres (PmPPMs) were prepared via an emulsification-solvent evaporation method. Scanning electron microscopy (SEM), powder X-ray diffraction (PXRD), and differential scanning calorimetry (DSC) were employed to investigate the presence of PRG in PmPPMs and its physical state changes during release. The addition of mPEG-PLGA altered the crystallinity of the drug within the microspheres at different release stages. The crystallinity correlated positively with the amount of mPEG-PLGA incorporated; the greater the amount, the faster the drug release from the formulation. The bioavailability and muscular irritation of the long-acting injectable were assessed through pharmacokinetic and muscle irritation studies in Sprague-Dawley (SD) rats. The results indicated that PmPPMs containing mPEG-PLGA achieved low burst release and sustained release over 7days, with minimal irritation and self-healing within this period. PmPPMs with 5% mPEG-PLGA showed a relative bioavailability (Frel) of 146.88%. In summary, adding an appropriate amount of mPEG to PLGA microspheres can alter the drug release process and enhance bioavailability.

Pressure-induced hydrogen bonding modulating Fermi resonance between fundamental modes in xylitol molecule

Xylitol, as a typical polyol, has a broad range of application prospects. However, the molecular states of xylitol under different environments are rarely reported until now. In this work, the state changes of xylitol molecules under high pressure were analyzed by Raman spectra. A Fermi resonance phenomenon in the fundamental mode of xylitol at 2945 (±0.06) cm−1 and 2955 (±0.41) cm−1 was observed at 0.99 GPa. The Fermi doublets possess the same symmetry and close energy levels, which had not been changed by pressures. However, the high pressure shortened the atomic distances and applied the extra disturbance, providing the necessary conditions for energy transfer. Besides, the Fermi doublets decoupling happened at 4 GPa due to the breaking of hydrogen bonding. This work provides an important reference for studying molecular states and weak interactions of polyols under high pressures.

Revealing the crucial roles of myxoma cells and CD206+ macrophages in cardiac myxoma progression based on single-cell sequencing.

e23549 Background: Cardiac myxoma is a commonly encountered tumor within the heart that has the potential to be life-threatening. However, the cellular composition and molecular characteristics of this condition are still not well understood. Methods: We performed single-cell sequencing on cardiac myxoma tissues obtained from 5 patients, focusing on the identification and characterization of cellular subtypes, cell trajectory analysis, and intercellular communication analysis. We performed a comparative analysis of the changes in cell types and states between cardiac myxoma and normal heart tissues. Furthermore, we retrospectively collected pathological sections from 49 cardiac myxoma cases and employed the multi-color immunohistochemistry (mIHC) technology to analyze the relationship between cellular infiltration and the severity of disease. Results: In total, 75,641 cells in cardiac myxoma tissues formed 9 distinct cell populations. Myxoma cells exhibited a significant resemblance to fibroblasts, yet they were distinguished by an increased expression of phosphodiesterases and genes associated with cell proliferation, differentiation, adhesion, and migration. Myxoma cells displayed cellular heterogeneity and demonstrated two distinct evolutionary pathways. One involves the transition from stem cell-like cells to stromal cells and the other involves enhancement of blood coagulation function. Immune cells surrounding the myxoma displayed suppressive features, with the presence of CD8+ T cells expressing TOX and GZMK, as well as a decrease in the secretion of cytotoxic molecules, indicating an impaired effector function. Macrophages were found to express growth factors such as EREG and PDGFC which played a role in promoting myxoma growth. Conversely, myxoma cells were also observed to secrete ANGPTL4 and ANXA1 which in turn induced the transformation of CD206+ macrophages. Extensive mIHC experiments indicated that a higher proportion of CD206+macrophages and myxoma cells infiltrating the myxoma tissues, along with their enhanced spatial interaction, were found to significantly contribute to the increased occurrence of embolism in cardiac myxoma patients. Conclusions: In summary, this study presents a comprehensive single-cell atlas of cardiac myxoma, highlighting the heterogeneity of myxoma cells and their collaborative impact on immune cells. These findings shed light on the complex pathobiology of cardiac myxoma and present potential targets for intervention.

Drought in play: A grounded socio-hydrological tool to increase social participation in drought plans

Drought management requires a proactive approach and active involvement of stakeholders to enhance effectiveness and equity. However, there are challenges such as power imbalances and knowledge disparities. This paper proposes an innovative methodological tool to facilitate the understanding of key concepts, such as drought states and reservoir zoning, alerts for changes in drought state, risk predisposition, breaking down hierarchical structures of teaching and learning, contributing to more horizontal and participatory processes. We present “Drought in Play” from its creation and design to its application in two water systems in the state of Ceará, located in the Northeast region of Brazil. The game encourages active participation in the creation of a proactive drought plan for water systems and stimulates critical thought and proactive actions regarding drought and water resources management. The game was designed for a multidisciplinary team and tested with researchers that know the drought plans methodology and the challenges to build an effective drought plan. “Drought in Play’’ includes game elements (cards, boardgame) and simulations. We explore the participants’ perceptions when using this tool to facilitate stakeholder participation in building a proactive plan to deal with drought and to enable water users to collectively manage a reservoir that is a common resource to all of them. The results suggest that ”Drought in Play“ can be used as a tool for socio-hydrological modeling, because it combines hydrological elements with social aspects such as decision-making, cooperation, and conflicts among participants. The game has potential to facilitate sustainable water resources management, enhance social learning, and provide a knowledge framework to address complex environmental challenges. It can be easily adapted to other regions with similar situations without requiring further modifications.

Noisy kinetic-exchange opinion model with aging.

We study the critical behavior of a noisy kinetic opinion model subject to resilience to change depending on aging, defined as the number of interactions before a change of opinion state. In this model, the opinion of each agent can take three discrete values, the extreme ones ±1, and also the intermediate value 0, and it can evolve through kinetic exchange when interacting with another agent, or independently, by stochastic choice (noise). The probability of change by pairwise interactions depends on the age that the agent has remained in the same state, according to a given kernel. We particularly develop the cases where the probability decays either algebraically or exponentially with the age, and we also consider the anti-aging scenario where the probability increases with the age, meaning that it is more likely to change mind the longer the persistence in the current state. For the opinion dynamics in a complete graph, we obtain analytical predictions for the critical curves of the order parameters, in perfect agreement with agent-based simulations. We observe that sufficiently weak aging (slow change of the kernel with the age) favors partial consensus with respect to the aging-insensitive scenario, while for sufficiently strong aging, as well as for anti-aging, the opposite trend is observed.

Development of Science Literacy Through Group Choice STEM-PjBL Projects Integrated with Matter State Changes

This research focuses on the development of students' science literacy in the topic of matter state changes at the primary school level. It utilizes Science, Technology, Engineering, and Mathematics - Project-Based Learning (STEM-PjBL) as a holistic integrative learning approach, supporting 21st-century skills. The meaningful learning design is crafted to help students understand the material while applying their understanding to a simple project appropriate for primary school students' cognitive levels. The study was conducted in a fifth-grade class at an educational unit in Tangerang City, Banten Province, Indonesia. Using a qualitative research method, data was collected through interviews, observations, reflective journals, and researchers' notes. The STEM-PjBL learning stages included reflection, research, discovery, application, and communication. The Shwartz assessment was developed as an instrument to evaluate students' science literacy abilities. The results show that implementing the STEM-PjBL approach promotes student-centered learning, builds group cooperation, is enjoyable, and develops students' science literacy. Students worked in groups on their chosen projects related to the topic of matter state changes. The average project score for each group received an A rating in completing the STEM-PjBL project. Interdisciplinary learning can encourage students to understand the characteristics and concepts of a theory and relate them to everyday life, thereby impacting their understanding and project development.

The ADnet Bayesian belief network for alder decline: Integrating empirical data and expert knowledge

The globalization in plant material trading has caused the emergence of invasive pests in many ecosystems, such as the alder pathogen Phytophthora ×alni in European riparian forests. Due to the ecological importance of alder to the functioning of rivers and the increasing incidence of P. ×alni-induced alder decline, effective and accessible decision tools are required to help managers and stakeholders control the disease. This study proposes a Bayesian belief network methodology to integrate diverse information on the factors affecting the survival and infection ability of P. ×alni in riparian habitats to help predict and manage disease incidence. The resulting Alder Decline Network (ADnet) management tool integrates information about alder decline from scientific literature, expert knowledge and empirical data. Expert knowledge was gathered through elicitation techniques that included 19 experts from 12 institutions and 8 countries. An original dataset was created covering 1189 European locations, from which P. ×alni occurrence was modeled based on bioclimatic variables. ADnet uncertainty was evaluated through its sensitivity to changes in states and three scenario analyses. The ADnet tool indicated that mild temperatures and high precipitation are key factors favoring pathogen survival. Flood timing, water velocity, and soil type have the strongest influence on disease incidence. ADnet can support ecosystem management decisions and knowledge transfer to address P. ×alni-induced alder decline at local or regional levels across Europe. Management actions such as avoiding the planting of potentially infected trees or removing man-made structures that increase the flooding period in disease-affected sites could decrease the incidence of alder disease in riparian forests and limit its spread. The coverage of the ADnet tool can be expanded by updating data on the pathogen's occurrence, particularly from its distributional limits. Research on the role of genetic variability in alder susceptibility and pathogen virulence may also help improve future ADnet versions.

Security concern and fuzzy output sliding mode load frequency control of power systems

This research investigates the concern of security in multi-area load frequency control (LFC) power systems using fuzzy logic output sliding mode control approach. A motion-trends-based deception attack model is proposed to represent malicious threats from communication networks. The motion-trends-based deception attack model enhances the destructive effect of deception attacks by monitoring changes in system state. In terms of the security concerns, a fuzzy-based output sliding mode control (OSMC) is applied to protect the power system from potential cyber-attacks. We provide sufficient conditions for the power systems stability under motion-trends-based deception attack. An initial controller gain that will bring the power system to stability is calculated by linear matrix inequalities (LMIs). The obtained controller gain provides a design method for fuzzy logic member functions. Fuzzy logic is then used to adjust the resulting controller gain to improve power system performance. The simulation results validate the usefulness of the proposed strategy, and indicate the viability of fuzzy logic in fine-tuning controllers.

Daily Time-Use Patterns and Quality of Life in Parents: Protocol for a Pilot Quasi-Experimental, Nonrandomized Controlled Trial Using Ecological Momentary Assessment.

The gender gap in time use and its impact on health and well-being are still prevalent. Women work longer hours than men when considering both paid and unpaid (eg, childcare and chores) work, and this gender disparity is particularly visible among parents. Less is known about factors that could potentially mediate or moderate this relationship (eg, work-family conflict and gender role beliefs). Ecological momentary assessment (EMA) allows for the documentation of changes in momentary internal states, such as time use, stress, or mood. It has shown particular validity to measure shorter-term activities (eg, unpaid work) and is thus useful to address gender differences. The feasibility of the daily EMA surveys in a parent sample will be examined. The associations between time use, well-being, and stress will be examined, along with potential moderating and mediating factors such as gender, gender role beliefs, and work-family conflict. Finally, the act of monitoring one's own time use, well-being, and stress will be examined in relation to, for example, the quality of life. We conducted a quasi-experimental, nonrandomized controlled trial with 3 data collection methods, namely, online questionnaires, EMA surveys, and qualitative interviews. The intervention group (n=64) will participate in the online questionnaires and EMA surveys, and a subsample of the intervention group (n=6-17) will also be invited to participate in qualitative interviews. Over a period of 1 week, participants in the intervention group will answer daily EMA surveys (4 times per day). In contrast, the control group (n=17) will only participate in the online questionnaires at baseline and after 1 week. The following constructs were surveyed: sociodemographic background (eg, age, gender, and household composition; baseline questionnaire); mediators and moderators (eg, gender role beliefs and work-family conflict; baseline and follow-up questionnaires); well-being, quality of life, and trait mindfulness (baseline and follow-up questionnaires); momentary activity and well-being, as well as state mindfulness (EMA); and feasibility (baseline and follow-up questionnaires as well as interviews). We anticipate that participants will regard the daily EMA as feasible. Particular daily time-use patterns (eg, high paid and unpaid workload) are expected to be related to lower well-being, higher stress, and health-related quality of life. These associations are expected to be moderated and mediated by factors such as gender, gender role beliefs, work-family conflict, and social support. Participants in the intervention group are expected to show higher values of mindfulness, well-being, health-related quality of life, and lower stress. Patient recruitment started in November 2023 and ended in mid April 2024. Data analysis commenced in mid April 2024. This study aims to provide valuable insights into the feasibility of using EMAs and the potential benefits of activity tracking in various aspects of daily life. Open Science Framework 8qj3d; https://osf.io/8qj3d. PRR1-10.2196/54728.

Chemical Environment and Structural Variations in High Entropy Oxide Thin Film Probed with Electron Microscopy.

We employ analytical transmission electron microscopy (TEM) to correlate the structural and chemical environment variations within a stacked epitaxial thin film of the high entropy oxide (HEO) Mg0.2Co0.2Ni0.2Cu0.2Zn0.2O (J14), with two layers grown at different substrate temperatures (500 and 200 °C) using pulsed laser deposition (PLD). Electron diffraction and atomically resolved STEM imaging reveal the difference in out-of-plane lattice parameters in the stacked thin film, which is further quantified on a larger scale using four-dimensional STEM (4D-STEM). In the layer deposited at a lower temperature, electron energy loss spectroscopy (EELS) mapping indicates drastic changes in the oxidation states and bonding environment for Co ions, and energy-dispersive X-ray spectroscopy (EDX) mapping detects more significant cation deficiency. Ab initio density functional theory (DFT) calculations validate that vacancies on the cation sublattice of J14 result in significant electronic and structural changes. The experimental and computational analyses indicate that low temperatures during film growth result in cation deficiency, an altered chemical environment, and reduced lattice parameters while maintaining a single phase. Our results demonstrate that the complex correlation of configurational entropy, kinetics, and thermodynamics can be utilized for accessing a range of metastable configurations in HEO materials without altering cation proportions, enabling further engineering of functional properties of HEO materials.

Torque curve bifurcation in T-shaped rotor continuously drilling into granular media

This study explores how a continuous drill of T-shaped rotor interacts with granular media and illustrates an universal torque bifurcation mechanism. Experiments shew that the drilling torque linear increases with depth initially, followed by bifurcation. The bifurcation types are intricately linked to the motion parameters of the rotor, while the depth of bifurcation and saturated torque are directly influenced by rotor geometry. DEM simulations link torque bifurcation to a low-stress fluidized region around the rotor, while the region is enclosed by a fluid–solid interface and influenced by the motion parameters. Moreover, force chain analysis demonstrates the irreversible state change of granular media disturbed by the rotor. Leveraging these insights, we propose two scaling laws quantifying the bifurcation point depth and the saturated torque, then perform qualitative analysis to explain the experimental phenomena. These findings may hold significant promise for practical engineering applications.

Incorporation of organic photochromic molecules in mesoporous silica materials: Synthesis and applications

Abstract The ability to control the function and structure of some promising nanosystems using an external stimulus is attractive research to develop programmable and reconfigurable intelligent nanomaterials. The focal point of this review is the silicon-based nanoporous materials, and particularly the mesoporous silica materials (MSMs) class (pore size: 2–50 nm), due to their important intrinsic properties, such as high surface area, highly ordered nanostructure, narrow pore size distribution, various dimensions (one-dimensional, two-dimensional, and three-dimensional), and easily functionable. One of the most essential organic components that can be incorporated in MSMs is organic photochromic molecules (OPMs), such as azobenzene, stilbene, dithienylethenes, and spiropyrans. OPMs can be incorporated into MSMs, to form photochromic mesoporous organosilica materials (PMOMs), in two different ways: physical (non-covalent immobilization) or chemical (covalent immobilization) binding. PMOMs are considered smart nanomaterials because they have the ability to undergo reversible changes in the solid state when exposed to an external electromagnetic radiation. PMOMs have been the subject of many research studies during the last decade due to their potential applications, especially as chemosensors. This review discusses the main families of OPMs, their incorporation into MSMs using different methods, and the applications of some PMOMs as chemosensors.

Investigation of Crack Propagation and Failure of Liquid-Filled Cylindrical Shells Damaged in High-Pressure Environments

Cylindrical shell structures have excellent structural properties and load-bearing capacities in fields such as aerospace, marine engineering, and nuclear power. However, under high-pressure conditions, cylindrical shells are prone to cracking due to impact, corrosion, and fatigue, leading to a reduction in structural strength or failure. This paper proposes a static modeling method for damaged liquid-filled cylindrical shells based on the extended finite element method (XFEM). It investigated the impact of different initial crack angles on the crack propagation path and failure process of liquid-filled cylindrical shells, overcoming the difficulties of accurately simulating stress concentration at crack tips and discontinuities in the propagation path encountered in traditional finite element methods. Additionally, based on fluid‒structure interaction theory, a dynamic model for damaged liquid-filled cylindrical shells was established, analyzing the changes in pressure and flow state of the fluid during crack propagation. Experimental results showed that although the initial crack angle had a slight effect on the crack propagation path, the crack ultimately extended along both sides of the main axis of the cylindrical shell. When the initial crack angle was 0°, the crack propagation path was more likely to form a through-crack, with the highest penetration rate, whereas when the initial crack angle was 75°, the crack propagation speed was slower. After fluid entered the cylindrical shell, it spurted along the crack propagation path, forming a wave crest at the initial ejection position.

Toward Practical Single-Molecule/Atom Switches.

Electronic switches have been considered to be one of the most important components of contemporary electronic circuits for processing and storing digital information. Fabricating functional devices with building blocks of atomic/molecular switches can greatly promote the minimization of the devices and meet the requirement of high integration. This review highlights key developments in the fabrication and application of molecular switching devices. This overview offers valuable insights into the switching mechanisms under various stimuli, emphasizing structural and energy state changes in the core molecules. Beyond the molecular switches, typical individual metal atomic switches are further introduced. A critical discussion of the main challenges for realizing and developing practical molecular/atomic switches is provided. These analyses and summaries will contribute to a comprehensive understanding of the switch mechanisms, providing guidance for the rational design of functional nanoswitch devices toward practical applications.

A new understanding of the causes of future change in El Niño teleconnection

Understanding and elucidating future changes in El Niño teleconnection is crucial because of the influence of El Niño on the globe via teleconnection. Existing climate models have consistently projected an eastward and poleward shift in El Niño teleconnection in the future, but the causes and dynamical processes of this shift have been poorly explained. Particularly, no study has examined the characteristic changes in the barotropic Rossby waves that form the teleconnection. This study investigates dynamic processes by analyzing the wavelength of the Rossby waves through spectral analysis, measuring the distance between circulation anomalies, and exploring the dispersion relationship of the barotropic Rossby waves. The results revealed that the wavelength of waves forming the teleconnection is expected to increase in warmer climate with an increase in the proportion of zonal-wavenumber-2 wave. Because changes in the mean state, including the strengthening of the westerly in the high-emission scenario, alter the frequencies of waves according to their zonal wavenumbers, this process is more notably manifested in the Southern Hemisphere, where the inter-model spread of the mean state is smaller, than in the Northern Hemisphere. Consequently, this will result in a shift in the position of El Niño's influence on the high latitudes of both Hemispheres. Specifically, in the Southern Hemisphere, it is anticipated that ocean warming in the seas in front of West Antartica and moisture transport towards Antarctica, induced by El Niño, will shift eastward in the high-emission scenario compared to its conventional position.

Digital phenotyping data and anomaly detection methods to assess changes in mood and anxiety symptoms across a transdiagnostic clinical sample.

Clinical assessment of mood and anxiety change often relies on clinical assessment or self-reported scales. Using smartphone digital phenotyping data and resulting markers of behavior (e.g., sleep) to augment clinical symptom scores offers a scalable and potentially more valid method to understand changes in patients' state. This paper explores the potential of using a combination of active and passive sensors in the context of smartphone-based digital phenotyping to assess mood and anxiety changes in two distinct cohorts of patients to assess the preliminary reliability and validity of this digital phenotyping method. Participants from two different cohorts, each n = 76, one with diagnoses of depression/anxiety and the other schizophrenia, utilized mindLAMP to collect active data (e.g., surveys on mood/anxiety), along with passive data consisting of smartphone digital phenotyping data (geolocation, accelerometer, and screen state) for at least 1 month. Using anomaly detection algorithms, we assessed if statistical anomalies in the combination of active and passive data could predict changes in mood/anxiety scores as measured via smartphone surveys. The anomaly detection model was reliably able to predict symptom change of 4 points or greater for depression as measured by the PHQ-9 and anxiety as measured for the GAD-8 for both patient populations, with an area under the ROC curve of 0.65 and 0.80 for each respectively. For both PHQ-9 and GAD-7, these AUCs were maintained when predicting significant symptom change at least 7 days in advance. Active data alone predicted around 52% and 75% of the symptom variability for the depression/anxiety and schizophrenia populations respectively. These results indicate the feasibility of anomaly detection for predicting symptom change in transdiagnostic cohorts. These results across different patient groups, different countries, and different sites (India and the US) suggest anomaly detection of smartphone digital phenotyping data may offer a reliable and valid approach to predicting symptom change. Future work should emphasize prospective application of these statistical methods.

Neutron spin echo shows pHLIP is capable of retarding membrane thickness fluctuations

Cell membranes are responsible for a range of biological processes that require interactions between lipids and proteins. While the effects of lipids on proteins are becoming better understood, our knowledge of how protein conformational changes influence membrane dynamics remains rudimentary. Here, we performed experiments and computer simulations to study the dynamic response of a lipid membrane to changes in the conformational state of pH-low insertion peptide (pHLIP), which transitions from a surface-associated (SA) state at neutral or basic pH to a transmembrane (TM) α-helix under acidic conditions. Our results show that TM-pHLIP significantly slows down membrane thickness fluctuations due to an increase in effective membrane viscosity. Our findings suggest a possible membrane regulatory mechanism, where the TM helix affects lipid chain conformations, and subsequently alters membrane fluctuations and viscosity.

Study on the Evolution of Physicochemical Properties of Carbon Black at Different Regeneration Stages of Diesel Particulate Filters Regenerated by Non-Thermal Plasma

As a new type of aftertreatment technology, non-thermal plasma (NTP) can effectively decompose the particulate matter (PM) deposited in diesel particulate filters (DPFs). In this paper, a regeneration test of a DPF loaded with carbon black was carried out using an NTP injection system, and the changes of oxidative activity, elemental content, and occurrence state, microstructure and graphitization degree of carbon black were analyzed to reveal the evolution of the physicochemical properties of carbon black at different regeneration stages of the DPF regenerated by NTP. As the regeneration stage of the DPF advanced, Ti, Tmax, and Te of the carbon black at the bottom of the DPF decreased, which were higher than those at the regeneration interface. After the NTP reaction, the proportion of C element decreased to less than 80%, while the proportion of O element increased to more than 20%; C-O was converted to C=O and the relative content of C=O increased. The average microcrystalline length and average spacing decreased, while the average microcrystalline curvature increased. The ID1/IG (relative peak intensities) of carbon black samples decreased from 3.31 to 3.10, and the R3 (relative peak intensities, R3 = ID3/(IG + ID2 + ID3)) increased from 0.41 to 0.58. The content of carbon clusters had a great influence on the disorder of the microcrystalline structure, so the graphitization degree of carbon black decreased and the oxidation activity increased.

SnO2 Interacted with Sodium Thiosulfate for Perovskite Solar Cells over 25% Efficiency.

Tin oxide (SnO2) as electron transportation layer (ETL) has demonstrated remarkable performance applied in perovskite solar cells but still accommodated a host of defects such as oxygen vacancies, uncoordinated Sn4+ , and absorbed hydroxyl groups. Here, we use inorganic sodium thiosulfate Na2S2O3 to modify SnO2 nanoparticles in a bulk blending manner. Strong interaction between Na2S2O3 and SnO2 occurs, as reflected from the elemental chemical state change. The interaction has endowed the SnO2 film with better uniformity, increased conductivity, and more matched energy level with perovskite. Moreover, the modified SnO2 film as a substrate could promote the crystallization of perovskite by suppressing unreacted residual PbI2. The trap density from perovskite bulk to the SnO2 film across their interface has been effectively reduced, thus inhibiting the nonradiative recombination and promoting the transportation and extraction of charge carriers. Finally, the solar cell based on modified SnO2 has achieved a champion efficiency of 25.2%, demonstrating the effectiveness and potential of sulfur-containing molecules on optimizing the SnO2 property.