Molecular Interface Research Articles

'Molecular Beam Epitaxy' on Organic Semiconductor Single Crystals: Characterization of Well-Defined Molecular Interfaces by Synchrotron Radiation X-ray Diffraction Techniques.

Epitaxial growth, often termed “epitaxy”, is one of the most essential techniques underpinning semiconductor electronics, because crystallinities of the materials seriously dominate operation efficiencies of the electronic devices such as power gain/consumption, response speed, heat loss, and so on. In contrast to already well-established epitaxial growth methodologies for inorganic (covalent or ionic) semiconductors, studies on inter-molecular (van der Waals) epitaxy for organic semiconductors is still in the initial stage. In the present review paper, we briefly summarize recent works on the epitaxial inter-molecular junctions built on organic semiconductor single-crystal surfaces, particularly on single crystals of pentacene and rubrene. Experimental methodologies applicable for the determination of crystal structures of such organic single-crystal-based molecular junctions are also illustrated.

Formate hydrogenlyase, formic acid translocation and hydrogen production: dynamic membrane biology during fermentation

Formate hydrogenlyase-1 (FHL-1) is a complex-I-like enzyme that is commonly found in gram-negative bacteria. The enzyme comprises a peripheral arm and a membrane arm but is not involved in quinone reduction. Instead, FHL-1 couples formate oxidation to the reduction of protons to molecular hydrogen (H2). Escherichia coli produces FHL-1 under fermentative conditions where it serves to detoxify formic acid in the environment. The membrane biology and bioenergetics surrounding E. coli FHL-1 have long held fascination. Here, we review recent work on understanding the molecular basis of formic acid efflux and influx. We also consider the structure and function of E. coli FHL-1, its relationship with formate transport, and pay particular attention to the molecular interface between the peripheral arm and the membrane arm. Finally, we highlight the interesting phenotype of genetic mutation of the ND1 Loop, which is located at that interface.

Two-component carnitine monooxygenase from Escherichia coli: functional characterization, inhibition and mutagenesis of the molecular interface.

Gut microbial production of trimethylamine (TMA) from l-carnitine is directly linked to cardiovascular disease. TMA formation is facilitated by carnitine monooxygenase, which was proposed as a target for the development of new cardioprotective compounds. Therefore, the molecular understanding of the two-component Rieske-type enzyme from Escherichia coli was intended. The redox cofactors of the reductase YeaX (FMN, plant-type [2Fe-2S] cluster) and of the oxygenase YeaW (Rieske-type [2Fe-2S] and mononuclear [Fe] center) were identified. Compounds meldonium and the garlic-derived molecule allicin were recently shown to suppress microbiota-dependent TMA formation. Based on two independent carnitine monooxygenase activity assays, enzyme inhibition by meldonium or allicin was demonstrated. Subsequently, the molecular interplay of the reductase YeaX and the oxygenase YeaW was addressed. Chimeric carnitine monooxygenase activity was efficiently reconstituted by combining YeaX (or YeaW) with the orthologous oxygenase CntA (or reductase CntB) from Acinetobacter baumannii. Partial conservation of the reductase/oxygenase docking interface was concluded. A structure guided mutagenesis approach was used to further investigate the interaction and electron transfer between YeaX and YeaW. Based on AlphaFold structure predictions, a total of 28 site-directed variants of YeaX and YeaW were kinetically analyzed. Functional relevance of YeaX residues Arg271, Lys313 and Asp320 was concluded. Concerning YeaW, a docking surface centered around residues Arg83, Lys104 and Lys117 was hypothesized. The presented results might contribute to the development of TMA-lowering strategies that could reduce the risk for cardiovascular disease.

Molecular structure design and interface behavior of ionic liquids on metal surfaces: A theoretical study

The electrodeposition of Mo or Ni, a traditional and mature technique, is of vital importance in industrial applications owing to the extraordinary mechanical properties of these elements when used as assisted coatings. The exploration of green electrodeposition technology has attracted much attention, especially with ionic liquids (ILs) emerging as promising electrolytes or additives owing to their particular physical and electrochemical properties. Many experimental studies have been conducted in this field; however, theoretical calculation, which offers an effective and low-cost approach to designing and choosing appropriate ILs, has rarely been applied. With the rapid development of computational chemistry, calculation, modeling, and simulation of chemical systems have been an important technique to understand and predict behaviors at the molecular level. Combining computational chemistry with experimental study has emerged as a highly efficient methodology for accelerating the development of traditional experimental studies. In this work, the chemical properties of pyridine-base ILs are investigated by density functional theory for the prediction of their potential adsorption performance. Molecular dynamic (MD) simulations of the interfacial behavior between the designed ILs and Ni and Mo surfaces were carried out to evaluate the dynamic processes. In this way, potential ILs as high performance electrolytes and additives for electrodeposition can be chosen on a theoretical basis. The study can be regarded as providing theoretical guidance for choosing appropriate electrolytes or additives for electrodeposition as well as for understanding the interfacial behavior between ILs and metal surfaces.

Chiral-Molecule-Based Spintronic Devices.

Spintronics and molecular chemistry have achieved remarkable achievements separately. Their combination can apply the superiority of molecular diversity to intervene or manipulate the spin-related properties. It inevitably brings in a new type of functional devices with a molecular interface, which has become an emerging field in information storage and processing. Normally, spin polarization has to be realized by magnetic materials as manipulated by magnetic fields. Recently, chiral-induced spin selectivity (CISS) wasdiscovered surprisingly that non-magnetic chiral molecules can generate spin polarization through their structural chirality. Here, the recent progress of integrating the strengths of molecular chemistry and spintronics is reviewed by introducing the experimental results, theoretical models, and device performances of the CISS effect. Compared to normal ferromagnetic metals, CISS originating from a chiral structure has great advantages of high spin polarization, excellent interface, simple preparation process, and low cost. It has the potential to obtain high efficiency of spin injection into metals and semiconductors, getting rid of magnetic fields and ferromagnetic electrodes. The physical mechanisms, unique advantages, and device performances of CISS are sequentially clarified, revealing important issues to current scientific research and industrial applications. This mini-review points out a key technology of information storage for future spintronic devices without magnetic components.

Hydrated Anions: From Clusters to Bulk Solution with Quasi-Chemical Theory.

ConspectusThe interactions of hydrated ions with molecular and macromolecular solution and interface partners are strong on a chemical energy scale. Here, we recount the foremost ab initio theory for the evaluation of the hydration free energies of ions, namely, quasi-chemical theory (QCT). We focus on anions, particularly halides but also the hydroxide anion, because they have been outstanding challenges for all theories. For example, this work supports understanding the high selectivity for F– over Cl– in fluoride-selective ion channels despite the identical charge and the size similarity of these ions. QCT is built by the identification of inner-shell clusters, separate treatment of those clusters, and then the integration of those results into the broader-scale solution environment. Recent work has focused on a close comparison with mass-spectrometric measurements of ion-hydration equilibria. We delineate how ab initio molecular dynamics (AIMD) calculations on ion-hydration clusters, elementary statistical thermodynamics, and electronic structure calculations on cluster structures sampled from the AIMD calculations obtain just the free energies extracted from the cluster experiments. That theory–experiment comparison has not been attempted before the work discussed here, but the agreement is excellent with moderate computational effort. This agreement reinforces both theory and experiment and provides a numerically accurate inner-shell contribution to QCT. The inner-shell complexes involving heavier halides display strikingly asymmetric hydration clusters. Asymmetric hydration structures can be problematic for the evaluation of the QCT outer-shell contribution with the polarizable continuum model (PCM). Nevertheless, QCT provides a favorable setting for the exploitation of PCM when the inner-shell material shields the ion from the outer solution environment. For the more asymmetrically hydrated, and thus less effectively shielded, heavier halide ions clustered with waters, the PCM is less satisfactory. We therefore investigate an inverse procedure in which the inner-shell structures are sampled from readily available AIMD calculations on the bulk solutions. This inverse procedure is a remarkable improvement; our final results are in close agreement with a standard tabulation of hydration free energies, and the final composite results are independent of the coordination number on the chemical energy scale of relevance, as they should be. Finally, a comparison of anion hydration structure in clusters and bulk solutions from AIMD simulations emphasize some differences: the asymmetries of bulk solution inner-shell structures are moderated compared with clusters but are still present, and inner hydration shells fill to slightly higher average coordination numbers in bulk solution than in clusters.

Whole-body transcriptome mining for candidate effectors from Diuraphis noxia

BackgroundProteins within aphid saliva play a crucial role as the molecular interface between aphids and their host plants. These salivary effectors modulate plant responses to favour aphid feeding and facilitate infestation. The identification of effectors from economically important pest species is central in understanding the molecular events during the aphid-plant interaction. The Russian wheat aphid (Diuraphis noxia, Kurdjumov) is one such pest that causes devastating losses to wheat and barley yields worldwide. Despite the severe threat to food security posed by D. noxia, the non-model nature of this pest and its host has hindered progress towards understanding this interaction. In this study, in the absence of a salivary gland transcriptome, whole-body transcriptomics data was mined to generate a candidate effector catalogue for D. noxia.ResultsMining the transcriptome identified 725 transcripts encoding putatively secreted proteins amongst which were transcripts specific to D. noxia. Six of the seven examined D. noxia putative effectors, termed DnE’s (Diuraphis noxia effectors) exhibited salivary gland-specific expression. A comparative analysis between whole-body D. noxia transcriptome data versus the head and body transcriptomes from three other aphid species allowed us to define a catalogue of transcripts putatively upregulated in D. noxia head tissue. Five of these were selected for RT-qPCR confirmation, and were found to corroborate the differential expression predictions, with a further three confirmed to be highly expressed in D. noxia salivary gland tissue.ConclusionsDetermining a putative effector catalogue for D. noxia from whole-transcriptome data, particularly the identification of salivary-specific sequences potentially unique to D. noxia, provide the basis for future functional characterisation studies to gain further insight into this aphid-plant interaction. Furthermore, due to a lack of publicly available aphid salivary gland transcriptome data, the capacity to use comparative transcriptomics to compile a list of putative effector candidates from whole-body transcriptomics data will further the study of effectors in various aphid species.

P-724 Gene expression profiling of cumulus cells from women with adenomyosis disclose differential pattern to endometriosis: striking the chord for evaluation of a biomarker

Abstract Study question Can metabolic picture of cumulus cell (CC) assess assisted reproductive technology outcome/s in women with adenomyosis/endometriosis and have implications on treatment decisions? Summary answer The differentially expressed genes between uterine pathologies explain the functional gap to identify diagnostic/prognostic markers of CC and further dissect molecular contribution to oocyte maturation. What is known already A healthy intra-follicular environment supports achievement of oocyte developmental competence (ODC) largely via coordinated CC-follicular fluid (FF) crosstalk. Lately, promising studies document CC of endometriosis are involved in important pathways for ODC like oxidative phosphorylation, metabolism, mitochondrial function and acetylation to name a few. Similar presentation/s of adenomyosis to other gynecological diseases including endometriosis makes the diagnosis difficult. Given that the functional integrities of CCs are susceptible to concurrent pathological conditions, understanding the influence of CCs on oocyte quality compared to routine morphological analysis in presence of deleterious systemic or pelvic conditions may impact clinical decisions. Study design, size, duration Twenty-eight consented patients undergoing IVF-ICSI between January to December 2021at Institute of Reproductive Medicine, Kolkata were enrolled. CCs obtained and corresponding oocyte maturation was assessed. They were sub-stratified (n = 9) according to uterine pathologies: adenomyosis (Group A), and endometriosis (Group B) as diagnosed by transvaginal ultrasound (TVUS). Counterpart/s of male sub-fertility, defined by World Health Organization criteria (5th edition) was treated as control (Group C; n = 10). CC from mature MII and immature GV oocytes were compared. Participants/materials, setting, methods CCs collected following oocyte-denudation were evaluated by Trypan Blue viability test. Patient age and embryo development were recorded with respect to each cumulus complex. Real Time-quantitative polymerase-chain-reaction (qRTPCR) was performed for glycolysis (PFKP, PKM2, ALDOA, LDHA, TPI1), cholesterol-biosynthesis (CYP51, MVK, PMVK, EBP) and extracellular-matrix (PTGS2, PTX3, TNFAIP6, VCAN) related gene/s known to have important functions in cumulus expansion and metabolism. Patient characteristics and gene expression were correlated by Spearman’s correlation. P < 0.05 was considered statistically significant. Main results and the role of chance A significant higher (p < 0.001) age (A vs B: 35.77±2.33 vs 25.88± 1.76; A vs C: 35.77±2.33 vs 31.9±1.98) and increased number of oocytes retrieved (A vs B: 11.22±1.56 vs 8.55±0.88) was documented in adenomyosis cohort. Immature oocytes from Group A expressed enhanced cholesterol/steroid biosynthesis, with significant (A vs B; p < 0.01) up-regulation of CYP51, MVK, PMVK, EBP in spite of hyper-estrogenic environment in peripheral blood. On contrary, significant attenuation (p < 0.01) of cholesterol biosynthesis was documented in endometriosis cohort compared to control. Expression of PTGS2, PTX3 and VCAN was down-regulated (p < 0.001) (which together mediate cumulus expansion and oocyte maturation, as well as corpus luteum formation and maintenance and reduce spindle abnormalities) in both Group A and B. Expression/s of CC-PFKP and PKM2 was lower in immature compared to mature oocytes (B vs C; p < 0.01) in endometriosis making the duo responsible for follicular/oocyte growth, and embryonic development. This supports the role in promoting cumulus expansion and oocyte competence. Expression levels of other genes including ALDOA, LDHA, TPI1, and TNFAIP6 were not associated with oocyte maturity, and fertilization in either cohort/s. Interestingly, levels of VCAN, TNFAIP6, PTX3 changed significantly as a function of the subject’s age and embryo development. Limitations, reasons for caution Our findings are limited by the relatively small sample size and inherent biological variability of human samples. Several yet known or unknown factors are presumably involved in the implantation process of adenomyosis and/or endometriosis. Multi-centric systematic studies are needed to corroborate these findings and account for the probable confounding factors. Wider implications of the findings A differential metabolic dependence of CC play essential role in oocyte competence in adenomyosis influencing cumulus expansion and oocyte maturation. This would be useful to do further studies to know how molecular interface of implantation capacity with live-birth rate would be affected to complement embryonic morphological assessment/s. Trial registration number Not Applicable

Glycans as shapers of tumour microenvironment: A sweet driver of T-cell-mediated anti-tumour immune response.

Essentially all cells are covered with a dense coat of different glycan structures/sugar chains, giving rise to the so-called glycocalyx. Changes in cellular glycosylation are a hallmark of cancer, affecting most of the pathophysiological processes associated with malignant transformation, including tumour immune responses. Glycans are chief macromolecules that define T-cell development, differentiation, fate, activation and signalling. Thus, the diversity of glycans expressed at the surface of T cells constitutes a fundamental molecular interface with the microenvironment by regulating the bilateral interactions between T-cells and cancer cells, fine-tuning the anti-tumour immune response. In this review, we will introduce the power of glycans as orchestrators of T-cell-mediated immune response in physiological conditions and in cancer. We discuss how glycans modulate the glyco-metabolic landscape in the tumour microenvironment, and whether glycans can synergize with immunotherapy as a way of rewiring T-cell effector functions against cancer cells.

Microscopic Interface and Multiscale Failure Analysis of Proposed Molecular Chain Polymers Based on Aifantis Strain Gradient Theory.

A study on the microscopic morphology of real-world polymer blends and its mechanism of change showed that the microscopic morphology of equiproportional mixtures gradually changed from a dense body structure to a network structure with the addition of the total polymer concentration up to 20%; the microscopic morphology of mixtures with different proportions was characterized by the most uniform network structure of equiproportional mixtures when the total polymer concentration was 20%. The polymer acts as a defoamer in the mixed system. In this paper, the relationship between the microscopic morphology of each mixture and the physicochemical behavior of the two polymer chains in the mixed system was investigated on the basis of the Aifantis strain gradient theory. Molecular polymer microscopic interface and multiscale failure analysis are proposed. It is shown that for the dihedral angle distribution of four consecutive coarse-grained particles, the peaks obtained from all atomic-scale simulation data are reproduced in the coarse-grained model simulations. The deviation is within 2.5% in most places, except for the local area where the deviation exceeds 5%. Therefore, we have achieved good results for large-scale failures.

Influence of molecular structure and interface behavior on foam properties of rice bran protein nano-particles

According to our previous research, thermal-acidic treatment was an effective way to improve foaming properties, especially foam stability, of rice bran protein (RBP) samples. In this article, the molecular structure and interface behavior of native RBP and rice bran protein nano-particles (RBPNs) were characterized to illustrate the relevant mechanisms affecting foaming properties. The circular dichroism (CD) and intrinsic fluorescence measurements suggested that thermal-acidic treatment could increase the flexible conformation of RBPNs corresponding to a higher surface activity at the interface. The decrease in apparent viscosity of RBPNs also illustrated the improvement in foam capacity of RBPNs. Moreover, the studies of air-water interfacial behavior demonstrated that the interfacial interaction of RBPNs-1 behaved stronger resulting in forming a stronger and more stretchable interfacial viscoelastic film compared to native RBP, which was mainly related to the different intermolecular interactions at the interface between the RBPNs-1 and native RBP. Further, combined with the analysis of the foam microstructure, it could indicate that in addition to the effects of the interface film on foam stability, the RBPNs trapped in Plateau borders provided the jamming effect by impeding the flow and reducing the rate of drainage. These findings are helpful to understand the relationship between molecular structure, interface behavior, and foaming properties.

Advances in perception-functionalized organic field-effect transistors

<p indent="0mm">With the evolution of optoelectronics to intelligent systems, the development of organic materials and devices with sensing perception functionality has become a cutting-edge area. By modulating the conductive capability of conjugated semiconductors with electric field, organic field-effect transistors can not only serve as electronic switch to build flexible logic circuits, but can also combine the multifunctional molecular design and interface engineering to create different sensors, neural computing and adaptive devices. Over the past decade, sensory perception-functionalized organic field-effect transistors (OFETs) have attracted increasing attention and made great achievements. This review introduces the related research progress from the molecular design, interface modification to device design. Moreover, we summarize key strategy towards state-of-the-art sensory perception-functionalized OFETs, and finally propose the challenges and opportunities of this emerging frontier.

A Shared Anchor on Primary Sigma Factor SigA by the WhiB‐Like Proteins

WhiB‐like (Wbl) proteins are a unique group of iron‐sulfur cluster ([4Fe4S])‐containing transcription factors exclusive to actinobacteria. They play crucial roles in the virulence, survival, and propagation of Mycobacterium tuberculosis (Mtb), the causative agent of tuberculosis. Seven Wbl proteins (WhiB1‐WhiB7) are found in Mtbwith diverse regulatory roles. All Mtb Wbl proteins except for WhiB5 have been shown to interact with the conserved region 4 of the primary sigma factor (SigAr4) in RNA polymerase holoenzyme. Our recent structural and biochemical analyses indicate that two Wbl proteins, WhiB1 and WhiB7, bind to the same site on SigAr4 unexpectedly through tight hydrophobic interactions involving several conserved aromatic residues of the Wbl proteins and His516 of SigAr4. Substitution of these aromatic residues in either WhiB1 or WhiB7 at the molecular interface abolishes their binding to SigAr4. Here, we hypothesize that all Mtb Wbl proteins share a similar molecular interface when in complex with SigAr4, based on the primary sequence analysis and structural modeling. Using the site‐directed mutagenesis and the in vitro protein‐protein interaction assays, we confirm that all Mtb Wbl proteins, including WhiB5, bind to the same site on SigA centered on His516, and the conserved aromatic residues within the Fe‐S cluster binding pocket are required for SigA binding. The results from this study will offer insights into how the Wbl proteins are utilized in Mtb to orchestra gene expression in response to environmental cues in the host.

Molecular interface between food allergy diagnosis and treatment: Value of a multi-omics approach

Due to the ever-increasing prevalence of Food Allergy (FA) in the United States, many studies have been conducted to better understand mechanisms of Food Allergy, diagnosis, and treatment. Traditional diagnosis of FA can be time-consuming, less dependable, and can lead to severe allergic reaction in some patients. In this review, the latest evidence on testing, appropriate biomarkers for diagnosis, and treatment options are presented. The benefits of trained immunity (TRIM), oral immunotherapy (OIT), sublingual immunotherapy (SLIT), and Epicutaneous immunotherapy (EPIT) are discussed in this review as well. Common biomarkers of food allergies are discussed, including 2S albumins, T-cells, and basophil activation markers. The benefits of a multi-omics approach are highlighted by the complex nature of food allergies and the relationship between genes, proteins, metabolites, and the microbiome in response to allergens. Future possibilities of omics studies pertaining to food allergies are also presented to guide future research.

Molecular interface between food allergy diagnosis and treatment: Value of a multi-omics approach

Molecular interface between food allergy diagnosis and treatment: Value of a multi-omics approach

The first laminin G-like domain of protein S is essential for binding and activation of Tyro3 receptor and intracellular signalling

The homologous proteins Gas6 and protein S (ProS1) are both natural ligands for the TAM (Tyro3, Axl, MerTK) receptor tyrosine kinases. ProS1 selectively activates Tyro3; however, the precise molecular interface of the ProS1-Tyro3 contact has not been characterised. We used a set of chimeric proteins in which each of the C-terminal laminin G-like (LG) domains of ProS1 were swapped with those of Gas6, as well as a set of ProS1 mutants with novel added glycosylations within LG1. Alongside wildtype ProS1, only the chimera containing ProS1 LG1 domain stimulated Tyro3 and Erk phosphorylation in human cancer cells, as determined by Western blot. In contrast, Gas6 and chimeras containing minimally the Gas6 LG1 domain stimulated Axl and Akt phosphorylation. We performed in silico homology modelling and molecular docking analysis to construct and evaluate structural models of both ProS1-Tyro3 and Gas6-Axl ligand-receptor interactions. These analyses revealed a contact between the ProS1 LG1 domain and the first immunoglobulin domain of Tyro3, which was similar to the Gas6-Axl interaction, and involved long-range electrostatic interactions that were further stabilised by hydrophobic and polar contacts. The mutant ProS1 proteins, which had added glycosylations within LG1 but which were all outside of the modelled contact region, all activated Tyro3 in cells with no hindrance. In conclusion, we show that the LG1 domain of ProS1 is necessary for activation of the Tyro3 receptor, involving protein-protein interaction interfaces that are homologous to those of the Gas6-Axl interaction.

Molecular Reactivity and Interface Stability Modification in In‐Situ Gel Electrolyte for High Performance Quasi‐Solid‐State Lithium Metal Batteries

Quasi‐solid‐state lithium metal battery is a promising candidate for next generation high energy density and high safety power supply. Despite intensive efforts on electrolytes, uncontrolled interfacial reactions on lithium with electrolyte and patchy interfacial contacts still hinder its practical process. Herein, we bring in rationally designed F contained groups into polymer skeleton via in‐situ gelation for the first time to establish quasi‐solid‐state battery. This method achieves a capacity retention of 90% after 1000 cycles at 0.5C with LiFePO4 cathodes. The interface constructed by polymer skeleton and reaction with –CF3 lead to the predicted solid electrolyte interface species with high stability. Furthermore, we optimize molecular reactivity and interface stability with regulating F contained end groups in the polymer. Comparisons on different structures reveal that high performance solid stable lithium metal batteries rely on chemical modification as well as stable polymer skeleton, which is more critical to construct robust and steady SEI with uniform lithium deposition. New approach with functional groups regulation proposes a more stable cycling process with a capacity retention of 94.2% at 0.5C and 87.6% at 1C after 1000 cycles with LiFePO4 cathodes, providing new insights for the practical development of quasi‐solid‐state lithium metal battery.

Tailoring the Nature of Interface States in Efficient and Stable Bilayer Organic Solar Cells by a Transfer‐Printing Technique

AbstractBulk heterojunction organic solar cells (BHJ‐OSCs) are designed to overcome inefficient charge generation and limited exciton diffusion of organic semiconductors. However, there are some disadvantages involving inherent voltage losses, microstructure control, and operational instability. Bilayer solar cells (BL‐OSCs) without mixed regions are free from these problems and offer a platform to explore the photophysical processes at the donor–acceptor interface. Here, a breakthrough for n‐i‐p BL‐OSCs in charge generation efficiency is reported. A gradual adjustment of the molecular interface orientation of the polymer donor (PM6) is accompanied by the evolution of charge‐transfer states and Forster energy transfer. Besides, less recombination losses and superior morphological stability of BL‐OSCs are achieved at a PCE comparable to that of BHJ‐OSCs with similar layer thickness. This investigation confirms the feasibility of manufacturing BL‐OSCs by a transfer printing method and provides a versatile architecture to study fundamental interface phenomena in OSCs independent from microstructure disorder.

Cross-scale study on the influence of moisture-temperature coupling conditions on adhesive properties of rubberized asphalt and steel slag

In order to study the effects of moisture and temperature on the interfacial adhesion characteristics between rubberized asphalt and steel slag, the interfacial adhesion properties between rubberized asphalt and steel slag under different immersion temperatures were studied. At the molecular scale, the interaction between rubberized asphalt model and steel slag representative minerals (Ca3SiO5 and Ca2SiO4) models were studied by molecular dynamics simulation. The bonding properties between rubberized asphalt and steel slag were analyzed and studied by direct tensile bonding failure test at macro scale. Through the correlation analysis between the macro scale direct tensile bonding failure test results and the molecular scale interface interaction, the cross-scale performance of moisture temperature on the adhesion characteristics between rubberized asphalt and steel slag was revealed. The results show that the type of interaction between steel slag molecules and asphalt molecules is consistent with that of natural minerals, and they all interact by hydrogen bond. Water molecules on the surface of steel slag molecular distribution is in a stepped pattern, asphalt molecules on the surface of steel slag molecular distribution are more uniform. Under the influence of rising temperature, water molecules further gather to the surface of steel slag molecules, and asphalt molecules gather away from steel slag molecules. When the temperature rises from 40 °C to 50 °C, the interaction energy density between rubberized asphalt and steel slag molecules hardly changes, and the interaction energy density decreases significantly when the temperature rises to 60 °C. Under the action of tensile stress, Ca2SiO4 shows weaker interaction with rubberized asphalt, while the interface of Ca3SiO5 and rubberized asphalt is less affected by external force. At the same time, 60°C is more obvious as the threshold temperature of interface strength decline under the action of external force. There is a good power function correlation between the macro bonding failure energy density and the molecular interaction energy density. The regularity within each scale is consistent, which confirms the rationality of cross-scale analysis of the same observation object between different scales. However, there are still great differences in the absolute values of indexes between different scales, which indicates that the simple numerical correspondence cannot be carried out in the cross-scale analysis due to the different ideal degree of models.

Host-guest liquid gating mechanism with specific recognition interface behavior for universal quantitative chemical detection

Universal visual quantitative chemical detection technology has emerged as an increasingly crucial tool for convenient testing with immediate results in the fields of environmental assessment, homeland security, clinical drug testing and health care, particularly in resource-limited settings. Here, we show a host-guest liquid gating mechanism to translate molecular interface recognition behavior into visually quantifiable detection signals. Quantitative chemical detection is achieved, which has obvious advantages for constructing a portable, affordable, on-site sensing platform to enable the visual quantitative testing of target molecules without optical/electrical equipment. Experiments and theoretical calculations confirm the specificity and scalability of the system. This mechanism can also be tailored by the rational design of host-guest complexes to quantitatively and visually detect various molecules. With the advantages of versatility and freedom from additional equipment, this detection mechanism has the potential to revolutionize environmental monitoring, food safety analysis, clinical drug testing, and more.