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Luminescent metal-organic frameworks are an emerging class of optical sensors, able to capture and detect toxic gases. Herein, we report the incorporation of synergistic binding sites in MOF-808 through post-synthetic modification with copper for optical sensing of NO2 at remarkably low concentrations. Computational modelling and advanced synchrotron characterization tools are applied to elucidate the atomic structure of the copper sites. The excellent performance of Cu-MOF-808 is explained by the synergistic effect between the hydroxo/aquo-terminated Zr6O8 clusters and the copper-hydroxo single sites, where NO2 is adsorbed through combined dispersive- and metal-bonding interactions, We thank the Spanish Ministry of Science and Innovation MCIN/AEI/10.13039/501100011033 (grants No. PID2021-123839OB-I00, RYC2018-024328-I and CEX2018-000805-M for A.E.P.-P., grant No. RTI2018-101049-B-I00 for A.M., grants No. RTI2018-097508−BI00, CEX2020-001039-S and PID2021-128313OB-I00 for J.C.-G., grant No. PID2019-106315RB-I00 for V.A.d.I.P.O.), the “European Union NextGenerationEU/PRTR” (grant No. EUR2020-112294 for A.E.P.-P., grants No. PLEC2021-007906 and TED2021-130173B-C43 for V.A.d.I.P.O.), and the Regional Government of Madrid (TALENTO grants No. 2017-T1/AMB-5264 and 2021-5 A/AMB-20946 for A.M., grant No. S2018/NMT-4511 NMAT2D-CM for J.C.-G., Proyectos Sinérgicos de I + D grant No. Y2018/NMT-5028 FULMATEN-CM for J.C.-G., grant No. S2018/NMT-4367 FotoArt-CM for V.A.d.I.P.O.). V.A.d.I.P.O. acknowledges financial support from the European Research Council (ERC), through the HYMAP project (grant agreement No. 648319), under the European Union’s Horizon 2020 research and innovation programme. I.d.C.–V. and I.R.–M. acknowledge FPI-UAM fellowships from Universidad Autónoma de Madrid. C.C.-B. acknowledges the European Social Funds and the Regional Government of Madrid for a postdoctoral contract (PEJD-2018-POST/IND-7909). A.S. acknowledges financial support from the Margarita Salas programme (grant No. CA1/ RSUE/2021-00622). Part of this research was carried out at P02.1 beamline at DESY, a member of the Helmholtz Association (HGF), and utilising the computing facilities of CSUC. We acknowledge DESY (Hamburg, Germany), a member of the Helmholtz Association HGF, for the provision of experimental facilities. Parts of this research were carried out at PETRA III, and we would like to thank Dr. Welter for his assistance in using the P65 beamline. Beamtime was allocated for proposal I-20210304 EC

2D nanomaterials are widely investigated for biomedical applications, attributed to their large specific surface area, high therapeutic loading capacity, and unique optical, thermal, and/or electronic characteristics. Lattice defects affect the theranostic performance of 2D nanomaterials significantly by altering their electronic properties and chemical binding. Recent investigations have shown that defect-rich 2D nanomaterials are capable of enhancing tumor treatment through efficient drug delivery, photothermal and photodynamic therapies (PTT and PDT), and improving diagnostics via computed tomography (CT), photoacoustic and magnetic resonance imaging. This review summarizes recent progresses, including synthesis, characterization approach, and applications of defect-engineered 2D nanomaterials that are potentially useful in cancer treatment. The expert opinions are also proposed as the conclusion.

Succinic acid was used as a spacer to bind titanium dioxide onto nylon as a new approach to develop self-cleaning fibers. Photoinduced decomposition of stains was achieved within acceptable times under ultraviolet A irradiation, a component of both solar light and indoor lamps spectrum. The surface properties of this innovative film were determined by scanning electron microscopy, electron-dispersive X-ray spectroscopy and Fourier transform infrared spectroscopy. The self-cleaning process was evaluated by analyzing the discoloration of coffee and palm oil stains by ultraviolet/visible diffuse reflection spectroscopy and mineralization via CO2 evolution, recorded using an infrared sensor. The results indicate that grafting TiO2 onto nylon, a synthetic fiber, using succinic acid is a successful chemical binding method, leading to a new self-cleaning material for stain discoloration. This new material is a promising solution to save water and reduce wastewater generated by the use of conventional substances used in textile cleaning.

Acute respiratory viral diseases continue to dominate among the causes for seeking medical help. In the pediatric population, about 60 % of cases have a recurrent course, which in turn often leads to the development of post-viral asthenic syndrome. In such children, one can find rapid fatigability, attention disorders and inability to concentrate, impaired information processing, emotional lability, and sleep disorders. All this disrupts the usual way of life of both the child and his relatives that undoubtedly requires the treatment of this condition and complete restoration of the state of the body after episodes of acute respiratory diseases. Phytotherapy has found its place in the management of children with post-viral asthenia due to the polyvalence of the pharmacological action, proven efficiency, safety of long-term therapy with phytopreparations and economic attractiveness for the majority of the population. In modern realities, phytotherapy is used as a reductive therapy, which makes up for the lack of products of intermediate metabolism in the body; as detoxification therapy that provides adsorption or chemical binding of exo- and endotoxins, increasing the body’s resistance to them and stimulating the excretory systems. It is important to use the neurotropic, immunotropic, hormone-like action of biologically active substances of plants; natural compounds, actively modifying the functions of regulatory systems, have prospects in the treatment of complex diseases. Analysis of the search databases PubMed, Web of Science, Scopus, Google Scholar, RSCI, Index Copernicus, BMJ, MEDLINE on the possibility of use, efficacy and safety of phytocomponents of Alleva in children of different ages with symptoms of post-viral asthenia allowed to ensure the application of this drug to control manifestations of asthenic syndrome. The article analyzes the options for correcting childhood asthenia with dry concentrates of linden flowers, lemon balm, chamomile, extracts of passionflower, hop, orange tree and lavender., Гострі респіраторні вірусні захворювання продовжують домінувати серед причин звернень по медичну допомогу. У дитячій популяції близько 60 % випадків мають рекурентний перебіг, який, у свою чергу, часто призводить до розвитку поствірусного астенічного синдрому. У таких дітей можна виявити швидку втомлюваність, розлади уваги й здатності до концентрації, засвоєння інформації, емоційну лабільність, розлади сну. Усе це порушує звичний спосіб життя як дитини, так і її оточення, що, безперечно, потребує лікування даного стану й повного відновлення стану організму після епізодів перенесених гострих респіраторних захворювань. Фітотерапія знайшла своє місце в схемах ведення дітей з поствірусною астенією за рахунок полівалентності фармакологічної дії, доведеної ефективності, безпечності тривалої терапії фітопрепаратами й економічної привабливості для більшості населення. У сучасних реаліях фітотерапія використовується як редуктивна терапія, що поповнює в організмі нестачу продуктів проміжного обміну; як дезінтоксикаційна терапія, що забезпечує адсорбцію або хімічне зв’язування екзо- та ендотоксинів, підвищення резистентності до них організму й стимулювання видільних систем. Важливим є використання нейротропної, імунотропної, гормоноподібної дії біологічно активних речовин рослин, а природні сполуки, що активно модифікують функції регуляторних систем, мають перспективу в лікуванні складних захворювань. Аналіз пошукових баз PubMed, Web of Science, Scopus, Google Scholar, РИНЦ, Index Copernicus, BMJ, MEDLINE щодо можливості використання, ефективності й безпечності фітоскладових препарату Аллева в дітей різного віку із симптомами поствірусної астенії дозволив впевнитися в можливості застосування даного препарату з метою контролю проявів астенічного синдрому. У статті проаналізовано можливості корекції дитячої астенії сухими концентратами квіток липи, меліси лікарської, ромашки, екстрактами пасифлори, хмелю, плодів апельсинового дерева й лаванди.

Anodic oxygen evolution reaction (OER) is the key bottleneck for water electrolysis technique owing to its sluggish reaction kinetics. Interfacial engineering on the rationally designed heterostructure can regulate the electronic states efficiently for intrinsic activity improvement. Here, we report a co-phosphorization approach to construct a VPO4-Ni2P heterostructure on nickel foam with strongly chemical binding, wherein phosphate acts as electronic modifier for Ni2P electrocatalyst. Profiting from the interfacial interaction, it is uncovered that electron shifts from Ni2P to VPO4 to render valence increment in Ni species. Such an electronic manipulation rationalizes the chemical affinities of various oxygen intermediates in OER pathway, giving a substantially reduced energy barrier. As a result, the advanced VPO4-Ni2P heterostructure only requires an overpotential of 289 mV to deliver a high current density of 350 mA/cm2 for OER in alkaline electrolyte, together with a Tafel slope as low as 28 mV/dec. This work brings fresh insights into interfacial engineering for advanced electrocatalyst design.

Chloride attack on reinforced concrete is considered the most important aspect in concrete durability investigation. This study is carried out to investigate effect of curing condition on the chloride binding capacity of fly ash geopolymer pastes containing a range of cast in chloride contents (NaCL), varying from 1%, 2% and 4% by mass of binder. The applied curing regimes were normal, oven, steam and microwave. The impact of induced chlorides on the compressive strength and on the chloride binding capacity of fly ash geopolymers under different curing conditions is determined. A detailed microstructure and phase composition analysis were conducted through SEM and XRD tests. It was observed that applying thermal curing conditions could increase the chloride binding capacity to the formed geopolyric hydration product. High curing temperatures promote the precursor dissolution reactions and will increase the overall generation of polymerization reaction products, while under normal curing a lot of fly ash grains did not fully react. Therefore, thermal curing is important in the activation of geopolymerization process that increase aluminosilicate gel and result in dense and less porous geopolymer matrix and yields in high compressive strength. This results in the physical adsorption and chemical binding of chloride ions on the gel surface, and hence reducing the rate of chloride ingress. It was concluded that the ingress of chlorides can be particularly controlled better through binding the free chloride ions under steam and microwave curing in the fly ash geopolymer concrete.

The U.S. Transuranium and Uranium Registries whole-body tissue donor Case 0407 had an acute intake of ‘high-fired’ plutonium oxide resulting from a glove-box fire in a fabrication plant at a nuclear defence facility. The respiratory tract of this individual was dissected into five regions (larynx, bronchi, bronchioles, alveolar-interstitial, and thoracic lymph nodes) and analysed for plutonium content. The activities in certain compartments of the respiratory tract were found to be higher than expected from the default models described in publications of the International Commission on Radiological Protection. Because of the extremely slow rate of dissolution of the material inhaled, the presence of bound fraction is incapable of explaining the higher-than-expected retention. A plausible hypothesis—encapsulation of plutonium in scar tissues—is supported by the review of literature. Therefore, scar-tissue compartments corresponding to the larynx, bronchi, bronchioles and alveolar-interstitial regions were added to the existing human respiratory tract model structure. The transfer rates between these compartments were determined using Markov Chain Monte Carlo analysis of data on urinary excretion, lung counts and post-mortem measurements of the liver, skeleton and regional retention in the respiratory tract. Modelling of the data showed that approximately 30% of plutonium activity in the lung was sequestered in scar tissues. The dose consequence of such sequestration is qualitatively compared against that of chemical binding.

Information of the chemical, mechanical, and electrical properties of materials can be obtained using force volume mapping (FVM), a measurement mode of scanning probe microscopy (SPM). Protocols have been developed with FVM for a broad range of materials, including polymers, organic films, inorganic materials, and biological samples. Multiple force measurements are acquired with the FVM mode within a defined 3D volume of the sample to map interactions (i.e., chemical, electrical, or physical) between the probe and the sample. Forces of adhesion, elasticity, stiffness, deformation, chemical binding interactions, viscoelasticity, and electrical properties have all been mapped at the nanoscale with FVM. Subsequently, force maps can be correlated with features of topographic images for identifying certain chemical groups presented at a sample interface. The SPM tip can be coated to investigate-specific reactions; for example, biological interactions can be probed when the tip is coated with biomolecules such as for recognition of ligand–receptor pairs or antigen–antibody interactions. This review highlights the versatility and diverse measurement protocols that have emerged for studies applying FVM for the analysis of material properties at the nanoscale.

Inverted perovskite solar cells (IPSCs) attract growing interest because of their simple configuration, reliable stability, and compatibility with tandem applications. However, the power conversion efficiency (PCE) of IPSCs still lags behind their regular counterparts, mainly due to the more serious nonradiative loss. Here, we design three donor-π-acceptor (D-π-A) dipoles with various dipole moments to introduce extra electric fields at the interface of perovskites and electron transport materials via the binding between the carboxylate end group and under-coordinated divalent Pb. The chemical binding reduces the recombination centers, while the superposition of the built-in electric field facilitates the electron collection and the hole blocking. As a result, the nonradiative loss is diminished as the dipole moments of D-π-A dipoles increase, which contributes to a PCE of 21.4% with enhancement in both the open-circuit voltage and fill factor. The stability for an unencapsulated device is also improved due to the hydrophobic property of D-π-A dipoles.

Heavy metals in soil are dangerous contaminants that limit the development of modern agriculture. The terahertz time-domain spectroscopy technique has shown its potential for rapid detection of heavy metals. However, the related detection mechanism has not been revealed. We combined terahertz technology with path analysis to observe and identify lead pollution in soil at different pH levels (5.5, 7.0, 8.5), and to analyze the related mechanism. First, solutions with pH values of 5.5, 7.0, and 8.5 were configured to prepare the soil samples with lead contents of 300, 600, 900, and 1200 mg/kg. The pressed-slice method with a pressure of 3.5 t and 200 mg in weight was selected to produce the soil tablets at each level. The terahertz technique was used to provide the terahertz absorption spectra. Then, the distribution of each chemical binding state of lead in soil samples under different pH conditions was observed. Finally, a path analysis method was used to explore the influence of each chemical binding state on the terahertz spectrum. The results showed that the bound state of Fe–Mn oxide lead and exchangeable lead had the greatest influence on the terahertz spectral curve, promoting and inhibiting the terahertz absorption, respectively, whereas other bound states presented an auxiliary role. This research investigates the detection mechanism of the influence of different bound lead in the soil on the terahertz absorption spectrum and provides a theoretical basis for the development of a rapid detection method using terahertz technology.

Reducing wall drag in turbulent pipe and channel flows is an issue of great practical importance. In engineering applications, end-functionalized polymer chains are often employed as agents to reduce drag. These are polymers which are floating in the solvent and attach (either by adsorption or through irreversible chemical binding) at one of their chain ends to the substrate (wall). We propose a PDE model to study this setup in the simple setting where the solvent is a viscous incompressible Navier–Stokes fluid occupying the bulk of a smooth domain $$\Omega \subset {\mathbb {R}}^d$$ , and the wall-grafted polymer is in the so-called mushroom regime (inter-polymer spacing on the order of the typical polymer length). The microscopic description of the polymer enters into the macroscopic description of the fluid motion through a dynamical boundary condition on the wall-tangential stress of the fluid, something akin to (but distinct from) a history-dependent slip-length. We establish the global well-posedness of strong solutions in two-spatial dimensions and prove that the inviscid limit to the strong Euler solution holds with a rate. Moreover, the wall-friction factor $$\langle f\rangle $$ and the global energy dissipation $$\langle \varepsilon \rangle $$ vanish inversely proportional to the Reynolds number $$\mathbf{Re } $$ . This scaling corresponds to Poiseuille’s law for the friction factor $$\langle f\rangle \sim 1/\mathbf{Re } $$ for laminar flow and thereby quantifies drag reduction in our setting. These results are in stark contrast to those available for physical boundaries without polymer additives modeled by, for example, no-slip conditions, where no such results are generally known even in two-dimensions.

Zero thermal expansion (ZTE) is an intriguing phenomenon by virtue of its peculiar lack of expansion and contraction with temperature. The achievement of ZTE in a metallic material is a desired but challenging task. Here we report the ZTE behavior of a single-phase metallic VB2 compound, stacking with the V and B atomic layers along the c direction (αV = 2.18 × 10-6 K-1, 5-150 K). Neutron powder diffraction demonstrates that the ZTE behavior is entangled in the direct blocking of the lattice expansion along all crystallographic directions with temperature. X-ray photoelectron spectroscopy and density functional theory calculations indicate that strong covalent binding adheres the nearest-neighbor B-B and V-B pairs, which is proposed to control the ZTE within both the basal plane and the c direction. An intimate correlation is revealed between the covalent binding and the lattice parameters. Our work indicates the opportunity to design metallic ZTE with strong chemical binding in the future.

Although zwitterion nanomaterials exhibit outstanding antifouling property, hemocompatibility, and antibacterial activity, their poor solubility in organic solvents limits their practical applications. In the present study, natural lysine (amino acids) was surface-grafted onto one-dimensional (1D) TiO2 nanofibers (NFs) through an epoxy ring opening in which the 3-glycidyloxypropyl (dimethoxy) methyl silane was used as a coupling agent. Chemical binding and morphological studies, such as Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, and transmission electron microscopy, were conducted to confirm the successful grafting of lysine onto the TiO2 NFs. The lysine-grafted TiO2 NF-polyethersulfone (PES) membrane induced electrostatic interactions and increased the surface charges from -28 to 16 mV in ζ-potential analysis. The lysine exhibited zwitterion characteristics owing to the presence of amino (cations) and carboxyl (anions) functional groups. Moreover, the modified TiO2-PES zwitterion membranes exhibited good water flux performances compared to the pristine membrane. ZT-4 membrane displayed the highest water fluxand bovine serum albumin (BSA) rejection of 137 ± 1.8 L m-2 h-1 and 94 ± 1%, respectively. The cell viability results revealed that the zwitterion PES membrane had excellent biocompatibility with peripheral blood mononuclear cells. The present work offers a convenient strategy to improve the hydrophilicity, antifouling property, and hemocompatibility of modified TiO2-PES zwitterion membranes for their biomedical and blood-contacting applications such as hemodialysis.

Redox mediators (RMs) have been developed as efficient approaches to lower the charge polarization of Li-O2 batteries. However, the shuttle effect resulting from their soluble nature severely damages the battery performance, causing failure of the RM and anode corrosion. In this work, a chemical binding strategy based on a MXene-modified separator with a 3D porous hierarchical structure design was developed to suppress the I3- shutting in LiI-involved Li-O2 battery. As corroborated by experimental characterizations and theoretical calculations, the abundant -OH terminal groups on the MXene surface functioned as effective binding sites for suppressing the migration of I3-, while the 3D porous structure ensured the fast transfer of lithium ions. As a result, the Li-O2 battery with the MXene-modified separator showed no sign of redox shuttling compared with its counterparts in the full discharge/charge tests. In the meantime, the MXene-modified separator based-cell exhibited a stable cycle life up to 100 cycles, which is 3 times longer than the control samples. We believe that this work could provide insights into the development of separator modification for Li-O2 batteries with RMs.

The impact of annealing on the emission of InAs quantum dots (QDs) has been investigated in the GaAs/Al0.30Ga0.70As structures with different compositions of the quantum well (QW) layers covered of QDs: GaAs or Al0.10Ga0.75In0.15As. The heat treatments of the QD structures were carried out at 640°C or 710°C for 2 h in an argon atmosphere. To estimate the compositions of QDs and capping QWs, photoluminescence (PL) and high-resolution X-ray diffraction have been applied. The QD structure with the Al0.1Ga0.75In0.15As capping QWs has been characterized by a lower energy of the ground state emission (≈ 1.30 µm, 300°K), its highest intensity and the smaller full width at half maximum, compared to the QD structure with GaAs capping QWs. The extinction of the integrated PL intensity about 80 times was detected in the range 10–400 K for the QD structure with Al0.10Ga0.75In0.15As capping compared to this extinction more than 1000 times detected in the QD structure with GaAs capping. The advantages obtained in the QD structure with Al0.1Ga0.75In0.15As capping are attributed to the lower mismatch and stresses at the capping QW/InAs QD interfaces, as well as the higher chemical binding energy of the Al-As bonds, compared to their value for Ga-As, which decreases the interdiffusion efficiency of the Ga/In atoms.

Methods that are used in regenerative medicine rely on the inherent ability of living organisms to regenerate their tissue. If the size (volume) of a defect exceeds some critical level, regeneration can be initiated and maintained using resorbable porous scaffolds made of natural, artificial, or synthetic materials capable of temporary defect compensation. When modified with pharmaceutical products and specific proteins or cells, such porous scaffolds are referred to as tissue engineering constructs. Inorganic resorbable materials are most frequently used for bone tissue defect repair. Natural bone is a composite having a polymer (collagen) matrix filled with calcium phosphate nanocrystals in the form of insoluble calcium hydroxyapatite. For this reason, calcium phosphate-based materials are leaders of medical inorganic materials research. To date, resorbable biocompatible materials based on tricalcium phosphate, calcium pyrophosphate, brushite, monetite, and octacalcium phosphate have been developed. Calcium hydroxyapatite is known as an inorganic ion exchanger. Because of this, the composition of bone tissue includes, in addition to phosphate and calcium ions, carbonate, silicate, and sulfate ions, as well as sodium, potassium, magnesium, iron, strontium, zinc and some other metal ions. The fact that bone tissue contains anions substituting for orthophosphate ions or hydroxide ions in the calcium hydroxyapatite of bone tissue prompted researchers to produce resorbable materials based on calcium sulfates, calcium carbonate, and calcium phosphates in which orthophosphate ions are replaced by anions mentioned above. Cation substitutions in calcium hydroxyapatite of bone tissue and the chemical composition of the medium of an organism allow one to produce and use resorbable materials for bone implants consisting of cation-substituted calcium phosphates and calcium–biocompatible cation double phosphates, such as sodium-substituted tricalcium phosphate, potassium-substituted tricalcium phosphate, sodium rhenanite, potassium rhenanite, and calcium magnesium double pyrophosphate. The resorption of an inorganic material intended for use as a pharmaceutical product can be controlled via designing a preset phase composition. The above-mentioned biocompatible resorbable phases can be used in various combinations in already existing composite materials or composites under development. The microstructure of a biocompatible resorbable inorganic material can be formed as a result of various physicochemical processes. The phase composition and microstructure of a ceramic material are determined by solid-state and liquid-phase sintering processes, as well as by heterogeneous chemical reactions during firing. The phase composition and microstructure of cement stone are formed as a result of chemical binding reactions initiated by the addition of water or aqueous solutions. Amorphous materials can be prepared via melting of starting reagents or sol–gel processing. The osteoconductivity of a biocompatible resorbable inorganic material is an important property necessary for body fluids and bone cells to be able to penetrate into the implant material. Macroporosity, which determines the osteoconductivity of a resorbable inorganic material, can be produced using various technological approaches. 3D printing methods make it possible to obtain materials with tailored phase composition and microstructure and permeable macroporosity of preset architecture. A large surface area of a porous inorganic material is thought to be a factor of controlling the resorption rate. This review summarizes information about existing biocompatible resorbable inorganic materials for regenerative medicine and considers physicochemical principles of the preparation of such materials with the use of synthetic starting powders and natural materials.

The gene family of insect olfactory receptors (ORs) has expanded greatly over the course of evolution. ORs enable insects to detect volatile chemicals and therefore play an important role in social interactions, enemy and prey recognition, and foraging. The sequences of several thousand ORs are known, but their specific function or their ligands have only been identified for very few of them. To advance the functional characterization of ORs, we have assembled, curated, and aligned the sequences of 3902 ORs from 21 insect species, which we provide as an annotated online resource. Using functionally characterized proteins from the fly Drosophila melanogaster, the mosquito Anopheles gambiae and the ant Harpegnathos saltator, we identified amino acid positions that best predict response to ligands. We examined the conservation of these predicted relevant residues in all OR subfamilies; the results showed that the subfamilies that expanded strongly in social insects had a high degree of conservation in their binding sites. This suggests that the ORs of social insect families are typically finely tuned and exhibit sensitivity to very similar odorants. Our novel approach provides a powerful tool to exploit functional information from a limited number of genes to study the functional evolution of large gene families.