Low Mobility Research Articles

Controlled Phonon Transport via Chemical Bond Stretching and Defect Engineering: The Case Study of Filled β-Mn-Type Phases.

Controlling the elastic properties of the material could become a powerful tool for tuning the thermal transport in solids. Nevertheless, the impact of the crystal structure, chemical bonding, and elastic properties on the lattice thermal conductivity remains to be elucidated. This is a pivotal issue for the advancement of thermoelectric (TE) materials. In this context, the influence of cation substitution in tetrahedral voids on the structural, thermal, and TE properties of α- and β-PbyGa6-xInxTe10─filled β-Mn-type phases─is reported here. The investigated materials show semiconducting behavior and a change from p- to n-type conductivity, depending on the chemical composition and temperature. Our findings indicate that the electronic transport in β-Mn-type phases is largely influenced by the substantial distortion of the Te framework, which causes the low weighted mobility and strong scattering of charge carriers. The presence of a significant anharmonicity of lattice vibrations results in the ultralow lattice thermal conductivity of PbyGa6-xInxTe10 materials. With increasing x, κL decreases from 0.59 to an extremely low value of 0.36 W m-1 K-1 at 298 K due to the decrease of bonding energy, intensification of anharmonic thermal vibrations of atoms, and formation of point defects. This work demonstrates the efficacy of utilizing the crystal structure and elastic properties to regulate phonon transport in functional materials.

Kinematic analysis and experimental validation of a tripod parallel continuum manipulator

A tripod is a classical lower mobility parallel manipulator with three degrees of freedom. The usual geometrical constraints enforce a type of motion with two rotations on a horizontal plane and a translational motion in a vertical direction. These devices are applicable where a task requires a precise orientational motion. Nevertheless, some parasitic motions occur on the constrained degrees of freedom. Parallel Continuum Manipulators are devices where some elements have been replaced by slender rods whose deformation is source of mobility, allowing the elimination of some of the kinematic joints. This type of closed-loop compliant mechanisms have some features that can be useful in certain applications, e.g., the deformed state introduces a certain preload that avoids backslash, they have an inherent compliance that can be useful in some delicate tasks, and a certain control on wrench applied can be obtained. In this article, the comprehensive kinetostatic analysis of a tripod-type parallel continuum manipulator, 3 P ¯ FS , is explained and compared with that of its rigid counterpart 3 P ¯ RS . Workspace and singularity locus is obtained, positioning accuracy and wrench generation are evaluated experimentally.

Analysis of prospects and problems in the development of human resources for the employment of Ukrainian refugees

An influx of workers who have accumulated knowledge in labor markets other than the current one can have particularly large effects on the development of the host country's human resources. Other things being equal, a region with higher fluctuations in the number of highly skilled workers should be in a better position than a region with low mobility. Refugee laws are in constant evolution, reflecting the changing political, economic, and legal environments. This paper examines the situation that has developed in the Czech Republic after the arrival of a large number of refugees from Ukraine, in terms of their opportunities and prospects, as well as their ability to enter the labor market in accordance with their education and previous professional activities. The purpose of this study is to analyse the potential and obstacles to the labor integration of Ukrainian refugees, given the situation of uncertainty and the measures taken by the Czech government and state structures to receive refugees. The article considers the objective and subjective prerequisites for the labor integration of refugees, taking into account their socio-demographic characteristics and subjective intentions for the future.

Written Mobility Communication in Acute Care Medical Wards: An Observational Study of Physical Therapists' and Nurses' Documentation Practice.

Low inpatient mobility is associated with poor hospital outcomes. Poor communication between clinicians has been identified as a barrier to improving mobility. Understanding how mobility is communicated within the multi-disciplinary team may help inform strategies to improve inpatient mobility. The aim of this study was to describe written mobility communication by physical therapists and nurses in acute care medical wards. This cross-sectional observational study was conducted across 4 hospitals in an Australian health service. A survey of physical therapists and nurses identified preferred sources and content of written mobility communication. An audit described and compared written mobility communication in the most strongly preferred documentation sources. Findings were described and compared graphically between discipline and site. Questionnaires were completed by 85 physical therapists and 150 nurses. Twenty-two sources of documentation about mobility were identified. Preferences for sources and content varied between disciplines. Physical therapists nominated several preferred information sources and sought and documented broader mobility content. Nurses often sought nursing documents which focused on current mobility assistance and aids, with limited communication of mobility level or mobility goals. Audits of 104 patient records found that content varied between sources and sites, and content was variably missing or inconsistent between sources. Written mobility communication focused on mobility assistance and aids, rather than mobility levels or mobility goals, with poor completion and inconsistency within documentation. More complete and consistent documentation might improve progressive mobilization of hospital inpatients. Physical therapists and nurses seek and document different content in a wide range of locations, leading to incomplete and inconsistent written documentation.Understanding and resolving these practice differences offers potential to improve mobility communication and practice.

Hybrid System of Polystyrene and Semiconductor for Organic Electronic Applications

While organic semiconductors hold significant promise for the development of flexible, lightweight electronic devices such as organic thin-film transistors (OTFTs), photodetectors, and gas sensors, their widespread application is often limited by intrinsic challenges. In this article, we first review these challenges in organic electronics, including low charge carrier mobility, susceptibility to environmental degradation, difficulties in achieving uniform film morphology and crystallinity, as well as issues related to poor interface quality, scalability, and reproducibility that further hinder their commercial viability. Next, we focus on reviewing the hybrid system comprising an organic semiconductor and polystyrene (PS) to address these challenges. By examining the interactions of PS as a polymer additive with several benchmark semiconductors such as pentacene, rubrene, 6,13-bis(triisopropylsilylethynyl) pentacene (TIPS pentacene), 2,8-difluoro-5,11-bis(triethylsilylethynyl) anthradithiophene (diF-TES-ADT), and 2,7-dioctyl[1]benzothieno[3,2-b][1]benzothiophene (C8-BTBT), we showcase the versatility of PS in enhancing the crystallization, thin film morphology, phase segregation, and electrical performance of organic semiconductor devices. This review aims to highlight the potential of an organic semiconductor/PS hybrid system to overcome key challenges in organic electronics, thereby paving the way for the broader adoption of organic semiconductors in next-generation electronic devices.

Lethal Borna disease virus 1 infections of humans and animals – in-depth molecular epidemiology and phylogeography

Borna disease virus 1 (BoDV-1) is the causative agent of Borna disease, a fatal neurologic disorder of domestic mammals and humans, resulting from spill-over infection from its natural reservoir host, the bicolored white-toothed shrew (Crocidura leucodon). The known BoDV-1-endemic area is remarkably restricted to parts of Germany, Austria, Switzerland and Liechtenstein. To gain comprehensive data on its occurrence, we analysed diagnostic material from suspected BoDV-1-induced encephalitis cases based on clinical and/or histopathological diagnosis. BoDV-1 infection was confirmed by RT-qPCR in 207 domestic mammals, 28 humans and seven wild shrews. Thereby, this study markedly raises the number of published laboratory-confirmed human BoDV-1 infections and provides a first comprehensive summary. Generation of 136 new BoDV-1 genome sequences from animals and humans facilitated an in-depth phylogeographic analysis, allowing for the definition of risk areas for zoonotic BoDV-1 transmission and facilitating the assessment of geographical infection sources. Consistent with the low mobility of its reservoir host, BoDV-1 sequences showed a remarkable geographic association, with individual phylogenetic clades occupying distinct areas. The closest genetic relatives of most human-derived BoDV-1 sequences were located at distances of less than 40 km, indicating that spill-over transmission from the natural reservoir usually occurs in the patient´s home region.

In Situ Photoelectrochemical‐Induced Surface Reconstruction of BiVO4 Photoanodes for Solar Fuel Production

BiVO4 has been widely concerned due to its great potential in photoelectrochemical (PEC) water splitting. However, low carrier mobilities and high recombination efficiency of photogenerated carriers impede its photocatalytic performance. Herein, an in situ PEC cyclic‐voltammetry‐induced surface reconstruction of BiVO4 photoanodes (BVO pristine) is developed with significantly enhanced efficiency for solar water splitting. A series of in situ characterizations (including in situ X‐ray diffraction, in situ Raman), together with electrochemical tests and density‐functional theory calculations, reveal that during the photoelectrical activation process, the BVO pristine surfaces undergo a crystal plane reconstruction with greatly increased {040} crystal face to promote the separation of photogenerated carriers. In addition, abundant vanadium vacancies and oxygen vacancies are also introduced into the BiVO4 surface during the crystal face reconstruction process with more favorable surface water adsorption and increased injection efficiency of photogenerated carriers. Therefore, the charge‐transfer resistance (Rct) between BVO pristine and electrolyte under AM 1.5G illumination substantially reduced from the original 15 200 to 2820 Ω after the activation. Moreover, the photocurrent density of activated BVO pristines increases more than 12 times, relative to the original BiVO4. In this work, a new horizon for in situ photoelectric activation of semiconductor photoelectrodes with significantly enhanced PEC water splitting is provided.

Perception of Transaction Ease, Security and Trust on Customer Satisfaction in Using BSI Mobile Banking to Generation Z Customers in Jabodetabek

Problems faced by Bank Syariah Indonesia (BSI) regarding the development of digital banking technology in banking. Especially for BSI users mobile banking namely: (1) the percentage of use of BSI services is still low Mobile compared to service mobile banking other banks (2) review users who are still not satisfied with the ease of transactions (3) there are information security threats such as cases ransomware on BSI Mobile which causes a decrease in customer trust (4) internet use which is relatively high in generation Z, is not yet commensurate with usage mobile banking in generation Z which is still relatively low. The purpose of this research is to determine and analyze the influence of perceptions of convenience, security, trust and which variables have the greatest influence on customer satisfaction in using BSI mobile banking for Generation Z customers in Jabodetabek. The analytical method for testing customer satisfaction is carried out via google form, in this research using quantitative data with a sample of 350 generation Z customers in Jabodetabek using techniques purposive sampling. The analytical tool used is software SmartPLS version 4.1.0.3. Data analysis uses PLS-SEM analysis. This research data consists of descriptive data, outer model (test instrument) and inner model (hypothesis testing). The research results show that perceived ease of transactions and trust influence customer satisfaction in using BSI Mobile Banking for generation Z customers in Jabodetabek. Meanwhile, security has no effect on customer satisfaction in using BSI Mobile Banking for generation Z customers in Jabodetabek. The perception of ease of transactions has a greater influence compared to security and trust.

Job mobility, reallocation and wage growth: A tale of two countries

Job reallocation is a key driver of aggregate wage growth, but its role in different economic systems remains understudied. This paper takes a comparative view and analyses the role of job mobility in job reallocation and aggregate wage growth in Norway, comparing it to published results for the United States. The results show first that, as expected, overall job mobility is much lower in Norway compared to the United States, likely reflecting the compressed wage distribution. However, the speed of job reallocation from low-wage to high-wage firms is similar to or even higher than in the United States. Second, in both Norway and the United States, the process of job reallocation is strongly pro-cyclical. This is entirely driven by the pro-cyclical nature of net job-to-job mobility from low- to high-wage firms. Third, for Norway, the bulk of aggregate wage growth reflects on-the job wage growth, while its cyclicality is largely driven by net job-to-job mobility from low to high-wage firms. This paper shows that reallocation is not necessarily less efficient in more egalitarian societies with lower mobility and different wage structures.

Sarcopenia, frailty prevalence, and related factors in patients with stroke: A cross-sectional analytical study from Turkey.

Sarcopenia and frailty may develop at varying rates depending on the metabolic, structural, and functional changes in the muscle structure after stroke. To evaluate the prevalence of sarcopenia and frailty in patients with stroke and affecting clinical parameters. This was a cross-sectional and analytical study. Twenty-six (49.1%) women and 27 men (50.9%) with stroke with an average age of 60.2 ± 10.3 (median = 62) years were included in the study. To evaluate physical performance, balance, and mobility, we used the 4-meter walk test (4-MWT), timed up and go test, chair sit and stand test, and the Berg Balance Scale (BBS). Sarcopenia was diagnosed according to the Asian Working Group for Sarcopenia 2019 criteria. The SARC-F scale was used for sarcopenia. The average stroke duration was 21.6 ± 18.2 months. Prefrailty was present in 14 (26.4%) patients, frailty was present in 34 (64.2%) patients, and two (3.8%) patients were normal. Sarcopenia was detected in 28 (52.8%) patients. According to handgrip strength, the prevalence of low muscle strength was 17% (n= 9). In the sarcopenic group, female sex (p= 0.005) was more frequent, 4-MWT was longer (p= 0.003), chair stand test results were lower (p< 0.001), the clinical frailty scale (CFS) was higher (p< 0.001), fall risk was higher compared with the BBS (p< 0.001), there was lower HG strength (p= 0.009), lower malnutrition scores (PNI, prognostic nutritional index, p< 0.001), and lower lymphocyte counts (p= 0.037). EAT-10 scores and dysphagia presence (p= 0.026), the presence of malnutrition (p< 0.021) and Nottingham Health Profile score (p< 0.001) were higher in the sarcopenic group. Sarcopenia and frailty frequently develop in patients with chronic stroke, with low lymphocyte counts, physical performance, muscle strength, and mobility and balance scores, and it is associated with poor prognostic factors including high disease severity, dysphagia, malnutrition, risk of falling, and poor quality of life.

Advancements in optical and optoelectronic characteristics of benzotriazole-based asymmetric non-fullerene acceptors for organic photovoltaics

The development of energy-efficient non-fullerene acceptors (NFAs) has attracted much attention in producing efficient organic solar cells (OSCs). These innovative materials are considered a promising alternative to traditional fullerene acceptors because they absorb a broader light range and potentially enhance the OSC performance. Herein, we engineered eleven new asymmetric caterpillar-shaped materials with an A1-D-A2-A1 core as NFAs for OSCs. These efficient materials offer a high absorption efficiency, wide energy level range, and efficient charge transport capabilities. To engineer these caterpillar-shaped NFAs (FT1-FT11), we performed various synergistic modulations of end-capped electron-withdrawing moieties and side-chain engineering on the synthetic reference molecule (FT). The electron and hole reorganization energies, binding energy, transition energy, transition density analysis, electrostatic potential, and photovoltaic characterizations have been performed for these designed caterpillar-shaped (FT1–FT11) series. The designed materials (FT1–FT11) showed a lower binding energy of 0.45 eV, a narrower bandgap (2.11 eV), higher absorption (ranges from 700.44 nm to 781.05), and low electron and hole mobilities (0.0029 and 0.0031) compared to reference molecule FT. To investigate the charge transport process, we employed polymer donor PTB7-Th and efficient NFA acceptor FT11 to establish a donor:acceptor complex (FT11:PTB7-Th). The complex study demonstrates a significant charge transformation at the donor-acceptor interface. As a result, the developed compounds (FT1–FT11), with their superior optoelectronic capabilities, could be viewed as a viable and sustainable choice to fabricate next-generation efficient OSCs.

A FAIR comparison of activated carbon, biochar, cyclodextrins, polymers, resins, and metal organic frameworks for the adsorption of per- and polyfluorinated substances

Per- and polyfluorinated substances (PFAS) have complex sorption behaviors, complicating removal from water and selection of suitable adsorbents. We evaluated adsorption of 44 PFAS across four adsorbent groups: activated carbon and biochar (AC and BC), cyclodextrin-based adsorbents (cyclodextrins), polymer-based adsorbents and resins, and inorganic adsorbents and metal organic frameworks (MOFs). We analyzed over 500 adsorption coefficients (Kd) from literature, calculated at aqueous equilibrium concentration of 1 ± 0.3 µg/L under comparable experimental conditions. On average, Kd of AC and BC exceeded 107 L/kg for PFAS with C-F bonds > 7, unlike other adsorbents with Kd < 107. This trend holds for C-F bonds ≥ 4. Cyclodextrins, polymer-based adsorbents and resins outperform AC and BC for C-F bonds < 4. For AC and BC, Kd follows the order PFOS>PFOA>PFBS>PFBA, with adsorption increasing with increasing point of zero charge of the adsorbent. For AC and BC, as well as cyclodextrins, Kd values were related to PFAS hydrophobicity and steric properties. Additionally, adsorption was influenced by head group type, non-fluorinated carbon atoms, and the presence of oxygen and/or chlorine in the PFAS. No clear relationship was found for the other adsorbents. Adsorption prediction using a Random Forest Regressor and literature data was feasible for AC and BC, but not for other adsorbents. Cyclodextrins outperform AC and BC for removing PFAS across varying mobilities from water, whereas AC and BC are superior for low mobility PFAS. To support further data use all data and code used are freely available, following FAIR data principles.

Novel chitosan-enhanced alkali-activated material for remediation of zinc-contaminated coastal mudflat sediment

Sustainable utilization and development for contaminated mudflat sites face dual challenges associated with contaminant enrichment and engineering diseases, impacting ecological quality and coastal construction. Commonly used cement has limitations in ensuring geo-environmental engineering performances for polluted sediments. This study investigates a solidification/stabilization approach using novel chitosan-enhanced alkali-activated material (CTS-AAM) to remediate highly concentrated zinc-contaminated sediments. Results exhibit that the compressive strength and water stability of sediments are remarkably improved by CTS-AAM, satisfying engineering service even under long-term immersion and zinc accumulation. Significant improvements dependent on curing period and CTS-AAM dosage also reflect in the resistance to deformation of remediated sediments, maintaining low-compressibility states due to the enhancement of structural yield stress. The leaching toxicity of remediated sediments meets Zn ≤ 5.0 mg/L, as zinc primarily distributes to the residual fraction associated with low mobility. The bidirectional enhancement of toxic sediment is attributed to the generation of hydrates with cementitious and pore-filling effects through hydration reactions. Simultaneously, chitosan with hydrated gels and ettringite collectively form gel networks and compact skeleton structures within sediments, as well as immobilize Zn through comprehensive physical encapsulation, chemical binding, and chelation. This study provides a feasible strategy for future projects involving remediation and utilization of mudflats.

Re-evaluating the diffusivity of phosphorus in olivine: Implications of low diffusive mobility for thermochronology

Heterogeneities in the phosphorus (P) content of olivine are relatively resistant to diffusive homogenization when compared with other compositional heterogeneities. Thus, heterogeneities in the spatial distribution of P can preserve petrological information about olivine crystals from the earliest stages of crystallization which have been otherwise eliminated. However, compared to independent determinations of protracted cooling timescales in slowly cooled rocks, P enrichments are so sharp as to suggest a rate of diffusive mobility that is many orders of magnitude slower than previously suggested. Here, we heat single natural olivine crystals with sharply defined P heterogeneities (0.02–0.15 wt% P2O5 over 0.5 μm spatial scale) in a 1-atmosphere gas-mixing furnace for durations of 10–20 days at 1400°C, thus exposing them to conditions that should be sufficient for complete diffusive relaxation according to published P diffusivity values. However, high-precision chemical analysis of the same interior section before and after heating reveals no discernable difference in the sharpness of phosphorus concentration patterns. Therefore, diffusion chronometry applied to skeletal P enrichments in olivine currently provides erroneously short diffusive timescales. We discuss several possible causes for these discrepancies and the implications for diffusion chronometry as applied to phosphorus in olivine.

Lumbar Spine and Neural Tissue Mobilizations Improve Outcomes in Runners Presenting With Foot/Ankle Pathology: A Case Series.

Foot/ankle pain is common among runners. Inadequate management of runners with foot/ankle pain can lead to lost training time, competition removal, and other activity limitations. Neurodynamics, which refers to the integrated biomechanical, physiological, and structural function of the nervous system during movement, can be overlooked in patients with foot/ankle pain. Although a link between the cervical spine, neurodynamics, and upper quarter pain has been studied, less is known about the relationship between the lumbar spine and lower quarter. This case series describes the successful management of 3 runners with foot/ankle pain. Three female runners (ages 23, 24, and 45y) presented to physical therapy with foot/ankle pain and difficulty running. Each patient had positive examination findings with local foot/ankle testing. A comprehensive lumbar spine examination demonstrated impairments in range of motion and joint mobility that were hypothesized to be contributing. Positive lower quarter neurodynamic tests were also found. All patients were treated with nonthrust lumbar spine mobilization and lower quarter neural tissue mobilization. Changes in the Patient-Specific Functional Scale, Numerical Pain Rating Scale, Lower Extremity Functional Scale, and Global Rating of Change occurred after intervention targeting the lumbar spine and lower-extremity neurodynamics in all patients. This case series demonstrates the importance of including a thorough lumbar spine examination and neurodynamic testing to identify appropriate interventions while managing patients with foot/ankle pain, even when patients have signs indicative of local ankle/foot pathology. These examination procedures should be performed particularly when a patient is not responding to management targeting local foot/ankle structures.

Opto-electrical study of 4T perovskite-chalcogenide tandem solar cell with the addition of quasi-2D perovskite as capping layer of 3D perovskite layer

This study presents a four-terminal (4T) perovskite-chalcogenide tandem solar cell (TSC) that includes quasi-2D perovskite material in the top sub-cell in order to provide a stable structure, and the bottom sub-cell contains Zn(O,S,OH) material to provide a nontoxic buffer layer. First, a reference TSC with a total power conversion efficiency (PCE) of 26.48% is modeled, using MAPbI3 and CIGSSe as 3D perovskite and chalcogenide absorber layers (ALs), respectively. Next, two structures are designed to produce a stable SC using the Ruddlesden Popper (RP) quasi-2D perovskite materials, which have the chemical formula BA2MAm−1PbmI3m+1, m = 2–5. The initial structure uses quasi-2D perovskites in place of the 3D perovskite AL. According to the results, BA2MAPb2I7 represents the maximum PCE of 16.00%, 10.48% less than previously. This is caused by quasi-2D materials’ high Eg and low carrier mobility. In the second structure, 3D perovskite AL is capped with the quasi-2D perovskites. In terms of attaining maximum PCE, the optimal TSC is found for BA2MA3Pb4I13 with a PCE of 25.80%. Compared to the initial structure, this one’s PCE increased by 61.25%. In order to boost PCE, a 80 nm-thick anti-reflection (AR) layer is added to the second structure, and the PCE increased to 27.48%. Therefore, the final TSC is proposed as a 4T quasi-2D/3D perovskite-chalcogenide TSC that is stable, and has nontoxic buffer layer, with 3.78% more PCE than the reference structure.

Osteosarcopenia in Finland: prevalence and associated factors

SummaryThis cross-sectional study investigated osteosarcopenia prevalence and its correlates among 2142 adults aged 55 and older in Finland. Findings show 3.9% had osteosarcopenia, while 13.8% and 11.1% had probable sarcopenia only or osteoporosis only, respectively. Osteosarcopenia was associated with low BMI, impaired mobility, ADL limitations and depression. Sarcopenia appeared to drive these associations more than osteoporosis. Osteosarcopenia may be a risk factor for functional decline, hospitalization, and institutionalization, warranting further research.PurposeOsteosarcopenia is a disorder consisting of concurrent osteoporosis and sarcopenia. This cross-sectional study using nationally representative data from Finland in 2000 aimed to determine the prevalence of osteosarcopenia in Finland. In addition, associations of sociodemographic, lifestyle, anthropometric, physical and mental function indicators, chronic conditions and various biomarkers with osteosarcopenia were examined.MethodsThe study included 2142 subjects aged 55 and over (mean age 68.0 years, SD 9.0). Probable sarcopenia was defined as grip strength < 27 kg for men and < 16 kg for women. Osteoporosis was defined as either ultrasound-based bone density measurement of T < -2.5, or self-reported, pre-existing diagnosis of osteoporosis. Participants were categorized into 4 groups: no sarcopenia and no osteoporosis, probable sarcopenia only, osteoporosis only, and osteosarcopenia. Information on sociodemographic, lifestyle, anthropometric, physical and mental function indicators, chronic conditions and various biomarkers were collected via structured interview, questionnaires, clinical examination, and blood and urine samples.ResultsThe prevalence of probable sarcopenia, osteoporosis and osteosarcopenia was 13.8%, 11.1%, and 3.9%, respectively. Osteosarcopenia was associated with low BMI, slow gait speed, impaired mobility, impaired ability in the activities of daily living and depression. Of the two components, probable sarcopenia appeared to contribute to these associations more than osteoporosis.ConclusionAccording to representative population-based study, about every fifth person with probable sarcopenia also has osteoporosis. Mobility and ADL limitations were more common among people with osteosarcopenia than those with osteoporosis or probable sarcopenia alone. Future studies are needed to examine osteosarcopenia as an independent risk factor for functional decline, hospitalization, and institutionalization.

Role of the structural order of the hydration layer in regulating the heterogeneous ice nucleation efficiency

Understanding the complex microscopic mechanisms of heterogeneous ice nucleation is crucial across diverse fields from cloud science to microbiology. In this work, we examined the ability of solid surfaces to promote ice nucleation as a function of the structural order of interfacial water, including the first and second hydration layers. Comprehensive all-atom molecular dynamics simulations using the TIP4P/ice water model were conducted on a water film atop a modeled surface inspired by the (0001) surface of AgI crystal, with varying surface charges. These simulations revealed non-monotonic nucleation rates. The first hydration layer formed a hexagonal hydrogen-bond network resembling ice structures, exhibiting low mobility essential for inducing ice nucleation. Notably, the second hydration layer, acting as a key-point bridge, displayed varying degrees of orientational preference facilitated by inter-layer hydrogen bonds. The calculation of fluctuation parameters indicated that the greater structural order of the second layer significantly enhances the surface’s ice-forming capabilities. Unlike previous studies that focused primarily on the role of the first layer of interfacial water, our findings demonstrate that the second layer provides a more accurate indicator of ice nucleation capabilities.

Optimizing dye-sensitized solar cell efficiency through TiO2/CuS doping: effects of internal parameter variations

Dye-sensitized solar cells (DSSC) have attracted significant research interest due to their semi-transparency, ease of fabrication, cost-effectiveness, and environmental friendliness. This research focuses on enhancing dye-sensitized solar cells efficiency by doping titanium dioxide with copper sulfide and varying internal parameters such as concentration, thickness, and temperature. The primary issue addressed is the low electron mobility of titanium dioxide, which limits its performance as a photoanode. Using simulation methods, this study analyzed dye-sensitized solar cells performance under different doping conditions. The results showed that the highest efficiency of 8.18 % was achieved at a TiO2/CuS concentration of 0.3 %. The optimal photoanode thickness was approximately 3 μm, yielding an efficiency of 8.33 %. Temperature variations at room temperature (275 K, 300 K, and 325 K) resulted in efficiency values of 13.94 %, 15.06 %, and 16.18 %, respectively. These findings indicate that targeted doping and precise control of internal parameters can significantly enhance the performance of titanium dioxide-based dye-sensitized solar cells. The improved efficiency is attributed to enhanced electron mobility and better structural and morphological characteristics of the doped titanium dioxide photoanode. This research provides valuable insights into developing more efficient and sustainable dye-sensitized solar cells. The practical implications of these results are significant for advancing dye-sensitized solar cells as a viable alternative to conventional solar cells, contributing to the global effort to address the energy crisis by providing a cost-effective and environmentally friendly energy source.

Molecular Control of the Donor/Acceptor Interface Suppresses Charge Recombination Enabling High-Efficiency Single-Component Organic Solar Cells.

Single-component organic solar cells based on double cable polymers have achieved remarkable performance, with DCPY2 reaching a high efficiency of over 13%. In this study, DCPY2 is further optimized with an efficiency of 13.85%, maintaining a high fill factor (FF) without compromising the short circuit current. Despite its intermixed morphology, DCPY2 shows a reduced recombination rate compared to their binary counterpart (PBDB-T:Y-O6). This slower recombination in DCPY2 is attributed to the reduced wavefunction overlap of delocalized charges, achieved by spatially separating the donor and acceptor units with an alkyl linker, thereby restricting the recombination pathways. Adding 1,8-diiodooctane (DIO) into DCPY2 further reduced the recombination rate by facilitating acceptor aggregation, allowing free charges to become more delocalized. The DIO-assisted aggregation in DCPY2 (5% DIO) is evidenced by an increased pseudo-pure domain size of Y-O6. Fine molecular control at the donor/acceptor interface in the double-cable polymer achieves reduced non-geminate recombination under efficient charge generation, increased mobility, and charge carrier lifetime, thereby achieving superior performance. Nevertheless, the FF is still limited by relatively low mobility compared to the blend, suggesting the potential for further mobility improvement through enhanced higher-dimensional packing of the double-cable material.