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Featured Application: Thin polymer film durability and resistance to certain exposure tests. In this paper, a custom-tailored investigation protocol aimed at the tests of the resistance of bacteriostatic acrylic-based film containing silver nanoparticles is presented. As hospital appliance applications were considered, it was necessary to provide a unique approach, enabling specific media exposure and utilizing high-sensitivity measurement methods to observe fine indications of material wear. Due to the presence of nanoparticles in the tested film, nanometer-resolution surface imaging is necessary. Therefore, the main source of information about its degradation process is atomic force microscopy (AFM) measurements. This particular tool is an appreciated source of information, providing quantitative data about both morphological and mechanical changes in the properties of the surface. Using such an approach, supported by standard diagnostic methods, such as colorimetry and wettability angle determination, it was possible to enable insights into the way the bacteriostatic film deteriorates and evaluate its usefulness in medical appliance applications. Further tests of various films developed by companies can be performed using the described protocol to determine the lifetime of certain products. This paper reveals the company's practical utilization of both standardized and novel test techniques in the evaluation of new products. [ABSTRACT FROM AUTHOR]

A disposable voltammetric immunosensor was developed to measure breast cancer biomarker 15-3 (CA 15-3) in human saliva and serum samples. Screen-printed paper-based electrodes (f-SPE) previously fabricated by our research group using homemade conductive inks were used as transducers, which were later modified only with gold nanoparticles to immobilize anti-CA 15-3 antibodies. The sensor was operated using antigen–antibody interactions in conjunction with a redox species (ferrocyanide potassium) for the indirect determination of the CA 15-3 antigen. The device characterization involved atomic force microscopy (AFM) and electrochemical analysis. Optimization of the construction and response of the immunosensor was achieved at incubation times of 6 h for anti-CA 15-3, 1 h for bovine serum albumin, and 1 h for interaction with CA 15-3. The sensor displays a linear range between 2 and 16 U/mL, with a sensitivity of 0.012 μA/U mL−1, a limit of detection (LOD) of 0.56 U/mL, and a limit of quantification (LOQ) of 1.88 U/mL. The interfering substances minimally affected the signal, with 4.94% response variation, and the reproducibility of the immunosensor demonstrated a relative standard deviation (RSD) of 5.65%. The sensor successfully determined the CA 15-3 concentration in human serum and saliva, demonstrating its potential for clinical analysis. [ABSTRACT FROM AUTHOR]

This paper introduces a novel combined technique to characterize the elastic modulus gradient for glass/epoxy interphase. The developed procedure is applicable to all fiber-reinforced polymer (FRP) composites. Interphase in FRP composites plays a vital role in the mechanical performance of the material. Scientists almost characterized this region using nanoscale test methods such as atomic force microscopy (AFM) and scratch tests. These local methods characterize the elastic properties at a specific region near the fiber and, usually, are utilized for all regions around the fiber. This paper proposes a combined peridynamic and single-fiber micro tensile test method to characterize the overall elastic modulus gradient at the interphase region. The advantages of peridynamic as a non-local method are used to model the multiscale regions of interphase, fiber, and matrix. Single-fiber micro tensile tests are performed by the authors, and variations of displacements and strains are measured by the digital image correlation method. The obtained displacements are used as target values in the developed peridynamic code, and by performing peridynamic analyses, the elastic modulus variation along the interphase is automatically extracted. Furthermore, the variations of stresses and strains are investigated at the specimens' cross-section using different hypotheses for the interphase region. [ABSTRACT FROM AUTHOR]

This review paper provides an in-depth analysis of the significance of lipid nanocarriers in drug delivery and the crucial role of characterization techniques. It explores various types of lipid nanocarriers and their applications, emphasizing the importance of microscopy-based characterization methods such as light microscopy, confocal microscopy, transmission electron microscopy (TEM), scanning electron microscopy (SEM), and atomic force microscopy (AFM). The paper also delves into sample preparation, quantitative analysis, challenges, and future directions in the field. The review concludes by underlining the pivotal role of microscopy-based characterization in advancing lipid nanocarrier research and drug delivery technologies. [ABSTRACT FROM AUTHOR]

Nanomechanical testing plays a crucial role in evaluating surfaces containing nanoparticles. Testing verifies surface performance concerning their intended function and detects any potential shortcomings in operational standards. Recognising that nanostructured surfaces are not always straightforward or uniform is essential. The chemical composition and morphology of these surfaces determine the end-point functionality. This can entail a layered surface using materials in contrast to each other that may require further modification after nanomechanical testing to pass performance and quality standards. Nanomechanical analysis of a structured surface consisting of a poly-methyl oxazoline film base functionalised with colloidal gold nanoparticles was demonstrated using an atomic force microscope (AFM). AFM nanomechanical testing investigated the overall substrate architecture's topographical, friction, adhesion, and wear parameters. Limitations towards its potential operation as a biomaterial were also addressed. This was demonstrated by using the AFM cantilever to apply various forces and break the bonds between the polymer film and gold nanoparticles. The AFM instrument offers an insight to the behaviour of low-modulus surface against a higher-modulus nanoparticle. This paper details the bonding and reaction limitations between these materials on the application of an externally applied force. The application of this interaction is highly scrutinised to highlight the potential limitations of a functionalised surface. These findings highlight the importance of conducting comprehensive nanomechanical testing to address concerns related to fabricating intricate biomaterial surfaces featuring nanostructures. [ABSTRACT FROM AUTHOR]

This paper presents the design and fabrication of new types of polymer-based cantilevers for atomic force microscopy. The design and fabrication are aimed at the capability of 3D laser microprinting technology based on two-photon polymerization on a standard silicon substrate. IP-Dip commercial material from the Nanoscribe company was used for the fabrication of the designed cantilevers. The fabricated microprinted cantilevers facilitate precise manipulation at the nanoscopic scale, which is essential for studying nanomaterials' mechanical, electrical, and optical properties. The cantilevers' flexibility allows for the integration of functional elements such as piezoelectric layers and optical fibers, enabling combined measurements of multiple physical parameters. Various cantilever geometries, including rectangular and V-shaped, are examined, and their resonance frequencies are calculated. The experimental process involves preparing the cantilevers on a silicon substrate and coating them with aluminum for enhanced reflectivity and conductivity. Scanning electron microscope analysis documents the precise form of prepared polymer cantilevers. The functionality of the probes is validated by scanning a step-height standard grating. This study demonstrates the versatility and precision of the fabricated cantilevers, showcasing their potential for large-area scans, living cell investigation, and diverse nanotechnology applications. [ABSTRACT FROM AUTHOR]

This paper describes the improvements in microwave absorbency and other functional properties of silicone rubber-based nanocomposite sheets with iron (Fe)- and nickel (Ni)-deposited nanographite (NG). NG was synthesized using the ball milling method and then acid functionalized. The deposition was performed on acid-functionalized NG dispersed in an electrochemical bath containing Fe and Ni salts in a designed fluidized bed reactor system. The electrolyte concentration, stirring speed, applied current, and time of electrolysis were optimized. X-ray diffraction, Fourier transform infrared spectroscopy, Brenner–Emmet–Teller analysis, transmission electron microscopy, scanning electron microscopy, and atomic force microscopy were used to characterize the structural as well as morphological properties of the material. The applied current, average particle size, and density of the electrolyte–powder suspension have a significant impact on the material's morphology and microwave absorption capabilities. To measure tensile strength, electrical impedance, and microwave absorption in the 2–20 GHz range, co-deposited nanographite was mixed in a silicone rubber matrix and molded into 1.00–2.00 mm thick nanocomposite sheets. The nanocomposite sheets demonstrated a − 15 dB reflection loss in the 9–13 GHz frequency band with an absorber thickness of 1.24 mm. [ABSTRACT FROM AUTHOR]

In this paper, one of the great challenges faced by silicon-based biosensors is resolved using a biomaterial multilayer. Tiny biomolecules are deposited on silicon substrates, producing devices that have the ability to act as iridescent color sensors. The color is formed by a coating of uniform microstructures through the interference of light. The system exploits a flat, RNA-aptamer-coated silicon-based surface to which captured microbes are covalently attached. Silicon surfaces are encompassed with the layer-by-layer deposition of biomolecules, as characterized by atomic force microscopy and X-ray photoelectron spectroscopy. Furthermore, the results demonstrate an application of an RNA aptamer chip for sensing a specific bacterium. Interestingly, the detection limit for the microbe was observed to be 2 × 106 CFUmL−1 by visually observed color changes, which were confirmed further using UV-Vis reflectance spectrophotometry. In this report, a flexible method has been developed for the detection of the pathogen Sphingobium yanoikuyae, which is found in non-beverage alcohols. The optimized system is capable of detecting the specific target microbe. The simple concept of these iridescent color changes is mainly derived from the increase in thickness of the nano-ordered layers. [ABSTRACT FROM AUTHOR]

In this paper, the effect of a buffer layer created using different hydrogen-containing ratios of reactive gas on the electrical properties of a top-gate In-Ga-Zn-O thin-film transistor was thoroughly investigated. The interface roughness between the buffer layer and active layer was characterized using atomic force microscopy and X-ray reflection. The results obtained using Fourier transform infrared spectroscopy show that the hydrogen content of the buffer layer increases with the increase in the hydrogen content of the reaction gas. With the increase in the hydrogen-containing materials in the reactive gas, field effect mobility and negative bias illumination stress stability improve nearly twofold. The reasons for these results are explained using technical computer-aided design simulations. [ABSTRACT FROM AUTHOR]

Fine-grained soils containing diatom microfossils of biological origin are found worldwide. However, although these soils are acknowledged to have unique physical and mechanical properties, the exact role of diatoms in determining their compression and hydraulic behaviours remains unclear, especially when high effective stress is involved, and the underlying micromechanism is yet to be revealed. This study investigated the compression and permeability of diatomaceous soils prepared by mixing pure diatom and kaolin powders through one-dimensional constant rate of strain compression tests with a maximum vertical stress of 10 MPa. The microstructure of the soils studied was observed by atomic force microscopy, scanning electron microscopy and mercury intrusion porosimetry, and the microstructural evolution during compression was traced. The results indicate that the special hollow structure of diatom particles with internal pores contributes significantly to the high void ratio, compressibility and permeability of diatomaceous soils, and increasing the diatom content improves the pore distribution non-uniformity of the diatom–kaolin mixtures. In addition, the diatom particles have high brittleness and breakage potential, leading to microstructural rearrangement during compression, especially pore-structure adjustment. Lower compressive stress deforms the inter- and intra-aggregate pores, but higher vertical stress damages the diatoms' hollow structure, which changes the compression and hydraulic parameters in a different manner from the case of conventional clay. This paper enriches the knowledge concerning the multilevel behaviour of fine-grained soils containing diatom microfossils and provides a fundamental dataset. [ABSTRACT FROM AUTHOR]

Dialysis membranes are not hemocompatible with human blood, as the patients are suffering from the blood–membrane interactions' side effects. Zwitterionic structures have shown improved hemocompatibility; however, their complicated synthesis hinders their commercialization. The goal of the study is to achieve fast functionalization for carboxybetaine and sulfobetaine zwitterionic immobilization on PES membranes while comparing the stability and the targeted hemocompatibility. The chemical modification approach is based on an aminolysis reaction. Characterization, computational simulations, and clinical analysis were conducted to study the modified membranes. Atomic force microscopy (AFM) patterns showed a lower mean roughness for carboxybetaine-modified (6.3 nm) and sulfobetaine-modified (7.7 nm) membranes compared to the neat membrane (52.61 nm). The pore size of the membranes was reduced from values above 50 nm for the neat PES to values between 2 and 50 nm for zwitterionized membranes, using Brunauer–Emmett–Teller (BET) analysis. More hydrophilic surfaces led to a growth equilibrium water content (EWC) of nearly 6% for carboxybetaine and 10% for sulfobetaine-modified membranes. Differential scanning calorimetry (DSC) measurements were 12% and 16% stable water for carboxybetaine- and sulfobetaine-modified membranes, respectively. Sulfobetaine membranes showed better compatibility with blood with respect to C5a, IL-1a, and IL-6 biomarkers. Aminolysis-based zwitterionization was found to be suitable for the improvement of hemodialysis membranes. The approach introduced in this paper could be used to modify the current dialysis membranes with minimal change in the production facilities. [ABSTRACT FROM AUTHOR]

In the present paper the humidity sensing properties of regioregular rr-P3HT (poly-3-hexylthiophene) polymer films is investigated by means of surface acoustic wave (SAW) based sensors implemented on LiNbO3 (1280 Y-X) and ST-quartz piezoelectric substrates. The polymeric layers were deposited along the SAW propagation path by spray coating method and the layers thickness was measured by atomic force microscopy (AFM) technique. The response of the SAW devices to relative humidity (rh) changes in the range ~5–60% has been investigated by measuring the SAW phase and frequency changes induced by the (rh) absorption in the rr-P3HT layer. The SAW sensor implemented onto LiNbO3 showed improved performance as the thickness of the membrane increases (from 40 to 240 nm): for 240 nm thick polymeric membrane a phase shift of about −1.2 deg and −8.2 deg was measured for the fundamental (~78 MHz operating frequency) and 3rd (~234 MHz) harmonic wave at (rh) = 60%. A thick rr-P3HT film (~600 nm) was deposited onto the quartz-based SAW sensor: the sensor showed a linear frequency shift of ~−20.5 Hz per unit (rh) changes in the ~5–~50% rh range, and a quite fast response (~5 s) even at low humidity level (~5% rh). The LiNbO3 and quartz-based sensors response was assessed by using a dual delay line system to reduce unwanted common mode signals. The simple and cheap spray coating technology for the rr-P3HT polymer films deposition, complemented with fast low level humidity detection of the tested SAW sensors (much faster than the commercially available Michell SF-52 device), highlight their potential in a low-medium range humidity sensing application. [ABSTRACT FROM AUTHOR]

This paper describes a three-step process to remediate surface and sub-surface defects on chemo-mechanically polished SiC surfaces. In this process, a CF4-based inductively coupled plasma with reactive ion etch was used to remove material to a depth, which is unaffected by surface and subsurface polishing damage. This produced a planarized but carbon-rich fluorinated surface. This surface was then exposed to a 2 min rapid thermal oxidation in air at 1000 °C to oxidize and volatilize the excess carbon and fluorinated species, respectively. The resulting surface oxide was then stripped using a dilute hydrofluoric acid in water solution. This process, referred to as plasma assisted remediation, reproducibly yielded planarized, stoichiometric surfaces with low levels of carbon and oxygen contamination suitable for subsequent device fabrication. In the supporting studies described here, 4H- and 6H-SiC(0001) surfaces were remediated and characterized by x-ray photoelectron spectroscopy and atomic force microscopy at each stage of the process. Experimental studies under ion-rich and radical-dominant conditions are also reported which provide greater insight into the underlying chemistry and physics of the process. [ABSTRACT FROM AUTHOR]

This paper investigates the influence of constituent weight ratios on optical and electrical properties, with a particular focus on the intrinsic properties (such as electrical mobility) of ternary organic blends, highlighting the role of a third component. The study explores novel donor:acceptor1:acceptor2 (D:A1:A2) matrix blends with photovoltaic potential, systematically adjusting the ratio of the two acceptors in the mixtures, while keeping constant the donor:acceptor weight ratio (D:A = 1:1.4). Herein, depending on this adjustment, six different samples of 100–400 nm thickness are methodically characterized. Optical analysis demonstrates the spectral complementarity of the component materials and exposes the optimal weight ratio (D:A1:A2 = 1:1:0.4) for the highest optical absorption coefficient. Atomic force microscopy (AFM) analysis reveals improved and superior morphological attributes with the addition of the third component (fullerene). In terms of the electrical mobility of charge carriers, this study finds that the sample in which A1 = A2 has the greatest recorded value [ μ m a x = 1.41 × 10 − 4 cm 2 / (Vs )]. This thorough study on ternary organic blends reveals the crucial relationship between acceptor ratios and the properties of the final blend, highlighting the critical function of the third component in influencing the intrinsic factors such as electrical mobility, offering valuable insights for the optimization of ternary organic solar cells. [ABSTRACT FROM AUTHOR]

In this paper, Cu thin films were deposited on Si (100) substrates by the high−power impulse magnetron sputtering (HiIPMS) technique, and the effects of different duty cycles (from 2.25% to 5.25%) on the plasma discharge characteristics, microstructure, and electrical properties of Cu thin films were investigated. The results of the target current test show that the peak target current remains stable under 2.25% and 3% duty cycle conditions. Under the conditions of a 4.5% and 5.25% duty cycle, the target peak current shows a decreasing trend. The average power of the target shows a rising trend with the increase in the duty cycle, while the peak power of the target shows a decreasing trend with the increase in the duty cycle. The results of OES show that with the increase in the duty cycle, the total peak intensity of copper and argon emissions shows an overall increasing trend. The duty cycle from 3% to 4.5% change in copper and argon emission peak total intensity change is not obvious. The deposition rate and surface morphology of the copper film were investigated by scanning electron microscopy, and the deposition rate of the copper film increased with the increase in the duty cycle, which was mainly due to the increase in the average power. The surface roughness of the copper film was evaluated by atomic force microscopy. X−ray diffraction (XRD) was used to analyze the grain size and texture of the Cu film, and the results showed that the average grain size of the Cu film increased from 38 nm to 59 nm on the (111) and (200) crystal planes. Four−probe square resistance test copper film resistivity in 2.25%, 3% low duty cycle conditions of the copper film resistivity is generally higher than 4.5%, 5.25% high duty cycle conditions, the copper film resistivity shows the trend of change is mainly affected by the copper film grain size and the (111) face of the double effect of the optimal orientation. The lowest resistivity of the copper film measured under the 4.5% duty cycle condition is 1.7005 μΩ·cm, which is close to the intrinsic resistivity of the copper film of 1.67 μΩ·cm. [ABSTRACT FROM AUTHOR]

Gas detection is vital for safety in important industrial and private sectors. Its major significance lies in its proactive risk mitigation, safeguarding lives and resources. In this paper, the focus is on the development of a gas sensor based on quartz crystal microbalance coated with a sensitive layer of zinc oxide (ZnO)--graphene nanocomposite for the detection of volatile organic compounds at room temperature. The incorporation of graphene or reduced graphene oxide is preferred in such applications due to their excellent electrical conductivity, chemical stability, and high surface area. These nanocomposites were synthesized using a chemical method via spray pyrolysis. Various techniques were employed to analyze the coated QCM electrode: contact angle measurements to assess surface wettability, Fourier transform infrared and energy-dispersive X-ray spectroscopy to investigate the composition of the coated electrode, and scanning electron and atomic force microscopies were used to study its surface morphology. These analyses provided valuable insights into the nanocomposite's interaction with the environment, composition, structure, and topography of the sensor's sensitive layer. To evaluate the sensor's sensitivity, the frequency shift (_f) of the coated QCM electrode is monitored when exposed to different gas concentrations of ethanol, toluene, chloroform, humidity, and formamide, ranging from 47 to 142 ppm. The frequency shift indicated the detected gas concentration. The results demonstrate good repeatability and reversibility, which are crucial indicators of a sensor's reliability. This reliability is essential for applications in environmental monitoring or industrial safety, where accurate gas detection is critical. [ABSTRACT FROM AUTHOR]

Layered chalcogenides containing 3d transition metals are promising for the development of two-dimensional nanomaterials with interesting magnetic properties. Both mechanical and solution-based exfoliation of atomically thin layers is possible due to the low-energy van der Waals bonds. In this paper, we present the synthesis and crystal structures of the Mn2Ga2S5 and Mn2Al2Se5 layered chalcogenides. For Mn2Ga2S5, we report magnetic properties, as well as the exfoliation of nanofilms and nanoscrolls. The synthesis of both polycrystalline phases and single crystals is described, and their chemical stability in air is studied. Crystal structures are probed via powder X-ray diffraction and high-resolution transmission electron microscopy. The new compound Mn2Al2Se5 is isomorphous with Mn2Ga2S5 crystallizing in the Mg2Al2Se5 structure type. The crystal structure is built by the ABCBCA sequence of hexagonal close-packing layers of chalcogen atoms, where Mn2+ and Al3+/Ga3+ species preferentially occupy octahedral and tetrahedral voids, respectively. Mn2Ga2S5 exhibits an antiferromagnetic-like transition at 13 K accompanied by the ferromagnetic hysteresis of magnetization. Significant frustration of the magnetic system may yield spin-glass behavior at low temperatures. The exfoliation of Mn2Ga2S5 layers was performed in a non-polar solvent. Nanolayers and nanoscrolls were observed using high-resolution transmission electron microscopy. Fragments of micron-sized crystallites with a thickness of 70–100 nanometers were deposited on a glass surface, as evidenced by atomic force microscopy. [ABSTRACT FROM AUTHOR]

This paper introduces a paradigm shift in atomic force microscope (AFM) scan control, leveraging an artificial intelligence (AI)-based controller. In contrast to conventional control methods, which either show a limited performance, such as proportional integral differential (PID) control, or which purely focus on mathematical optimality as classical optimal control approaches, our proposed AI approach redefines the objective of control for achieving practical optimality. This presented AI controller minimizes the root-mean-square control deviations in routine scans by a factor of about 4 compared to PID control in the presented setup and also showcases a distinctive asymmetric response in complex situations, prioritizing the safety of the AFM tip and sample instead of the lowest possible control deviations. The development and testing of the AI control concept are performed on simulated AFM scans, demonstrating its huge potential. Highlights: Artificial intelligence-based asymmetric controller for the highest tip and sample safety with AFM scans. Potential to significantly outperform proportional integral derivative control in classical scan situations. Dynamic change between classically optimal and asymmetric behavior depending on the scan situation. [ABSTRACT FROM AUTHOR]

Gelatin, resulting from collagen, a naturally occurring protein found in ligaments and tissues, is formed through the boiling of connective tissues, bones and animal skins, commonly sourced from cows. Its exceptional properties, including the ability to form strong, transparent gels and flexible films, easy digestibility, solubility in hot water and positive binding action, make gelatin a highly valuable resource in various industries such as food processing, pharmaceuticals, photography and paper production. It is regarded as non-toxic, biocompatible, biodegradable and generally safe for use. Gelatin serves as a key ingredient in the manufacturing of a wide range of products, with a notable example being hard gelatin capsules, which come in varying levels of solubility in water. In this study, a Schiff base was synthesized by modifying gelatin with salicylaldehyde in ethanol at room temperature, a mixture of gelatin-Schiff base added to appropriate copper chloride sonicated in ethanol, the mixture was poured onto glass plates and allowed to dry. Modified gelatin film was produced and characterized using FTIR spectroscopy, while its surface properties were examined through Scanning Electron Microscopy (SEM) and Atomic Force Microscopy (AFM). Furthermore, the modified gelatin film's potential biological activity was assessed against bacterial strains. The antibacterial screening tests revealed that the modified gelatin exhibited promising antibacterial activity against microorganisms, indicating an improvement in its antibacterial efficacy. These findings highlight the enhanced antibacterial potential of the modified gelatin film, further contributing to its versatility and potential applications in various fields. Different molecular weight distributions within the gelatin can lead to variations in film formation and subsequent surface features. Additionally, the composition of the gelatin film, including the presence of any crosslinking agents or modified functional groups, can further influence the resulting surface morphology. This study focuses on the preparation of modified gelatin films using suitable aldehyde compounds and explores their potential for pharmaceutical applications. Various techniques assessment of biological activity will be employed to investigate the properties and performance of the modified gelatin films. [ABSTRACT FROM AUTHOR]

Drug delivery vehicles composed of lipids and gemini surfactants (GS) are promising in gene therapy. Tuning the composition and properties of the delivery vehicle is important for the efficient load and delivery of DNA fragments (genes). In this paper, we studied novel gene delivery systems composed of 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC), 1,2-dipalmitoyl-sn-3-phosphocholine (DPPC), and GS of the type N,N-bis(dimethylalkyl)- α , ω -alkanediammonium dibromide at different ratios. The nanoscale properties of the mixed DOPC–DPPC–GS monolayers on the surface of the gene delivery system were studied using atomic force microscopy (AFM) and Kelvin probe force microscopy (KPFM). We demonstrate that lipid–GS mixed monolayers result in the formation of nanoscale domains that vary in size, height, and electrical surface potential. We show that the presence of GS can impart significant changes to the domain topography and electrical surface potential compared to monolayers composed of lipids alone. [ABSTRACT FROM AUTHOR]

Carbon fiber powder (CFP) was first applied to conductive asphalt concrete as a conductive phase material, but its action mechanism has not been clarified. In this paper, atomic force microscopy (AFM) and molecular dynamics (MDs) simulation are used to study the carbon fiber powder mechanism of action, guide the preparation of conductive asphalt concrete, and study the electrothermal properties of conductive asphalt concrete. The results show that carbon fiber powder weakens the adhesion property of asphalt mastic, and this weakening further strengthens in the water–temperature coupling, so water stability and conductivity are used as evaluation indicators to determine that the optimal content of carbon fiber powder is 2.0% and that the optimal content of carbon fibers (CFs) is 0.4%. Carbon fiber–carbon fiber powder conductive asphalt concrete with a resistivity of 0.98 Ω · m was finally prepared. In the temperature rise test of the Marshall specimen and rutting slab, its warming effect is obvious, and the heat transformation rate is more than 75%, so it has a very good ability to melt snow and ice. [ABSTRACT FROM AUTHOR]

Two-dimensional transition metal chalcogenides (2D-TMDs) have attracted much attention because of their unique layered structure and physical properties for transistor applications. Mechanically transferred metal contacts on these low-dimensional materials or their homogeneous and heterogeneous multilayers have generated huge interest to avoid deposition damages. In this paper, we show that there are large physical gaps at both the edge contact and surface contact between the transferred electrodes and the 2D materials. A method called laser shock induced superplastic deformation (LSISD) is proposed to tackle this issue and enhance the performance of the transistors. The enhancement mechanism was investigated by molecular dynamics (MD) simulations of the nanoforming process, atomic force microscopy (AFM), scanning electron microscopy (SEM), transmission electron microscopy (TEM) characterizations of the interfaces, and density functional theory (DFT) modeling. The force effect of laser shock can reduce the contact gap between metals and semiconductors. The electrical performances of the transistors before and after LSISD, along with MD simulations, are used to find the optimal process parameters. In addition, this paper applies the LSISD method to the short-channel MoS2/graphene vertical transistors to show potential improvement in interface contact and electrical properties. This paper demonstrates the first report on using mechanical force induced by laser shock to enhance metal–semiconductor interfaces and transistor performances. [ABSTRACT FROM AUTHOR]

BACKGROUND: Cells adherence provides specific information about physiology and pathology, the adhesion measurement between living cells and nanostructures can be measured by atomic force microscopy, but this detection technique is difficult to operate and costly. The adhesion height and effective contact area between cells and substrates are also the key factors affecting measurement value of the overall impedance. These factors change with structural parameters of the substrates, so the adhesion measurement between living cells and substrate can be indirectly reflected by the impedance value. OBJECTIVE: To establish a mapping relationship between the impedance measurement and the adhesion measurement of living cells. The possibility of dynamic measurement of adhesion is realized by this method, and the experimental process is simplified. METHODS: Laser interference technology was used to prepare nanoarray structures with different periods on the surface of silicon wafers for cells culture. Under the same experimental conditions, the impedance of living cells on the substrates of different cycle sizes were measured. The adhesion between cells and different substrates were analyzed by measuring impedance after the interaction between cells and substrate. RESULTS: The adhesion of living cells on the substrates of different sizes be analyzed, and the mapping relationship between the impedance and the adhesion measurement was established. The results showed that, the larger the impedance value between cells and substrate, the larger the effective contact area and the smaller the gap between them. CONCLUSION: The difference of adhesion height and effective adhesion area between living cells and substrates were obtained. This paper, a new method to measure the adhesion properties of living cells is presented, which provides theoretical basis for the related research. [ABSTRACT FROM AUTHOR]

This paper presents a groundbreaking study on the synergistic effect of combining Cloisite 30B (C30B) organoclay with styrene-butadiene-grafted glycidyl methacrylate (SbB-g-GMA), a dual-functional impact modifier and compatibilizer with the ultimate aim of developing high-performance materials based on polyethylene terephthalate (PET), and polystyrene (PS) with superior thermal and mechanical properties, thereby exploring the feasibility of recycling of these commonly used plastics via a simple melt blending approach. The morphology of the melt-mixed PET/PS blends and dispersion state of organoclay in the PET/PS/C30B nanocomposites in the presence and absence of the compatibilizer were analyzed by the X-ray diffraction, field emission scanning electron microscopy (FE-SEM), atomic force microscopy (AFM), and transmission electron microscopy (TEM). Furthermore, the thermal and mechanical properties of the nanocomposites were evaluated through TGA/DSC analysis and tensile and Izod impact tests. The microscopic images revealed that the addition of the SbB-g-GMA compatibilizer resulted in a superior dispersion of the nanoclay platelets. The composition of 70% PET, 30% PS, 7 phr SbB-g-GMA, and 3 phr C30B yielded the best dispersion of C30B and the most favorable thermomechanical properties in the PET/PS/SbB-g-GMA/C30B blend. Interestingly, the study found that using the nanoclay alone was insufficient to achieve compatibility between PET and PS. Optimal results were obtained when SbB-g-GMA was mixed into the PET/PS/C30B nanocomposite. The mechanical properties, including tensile and impact strength, modulus, elongation at break, as well as the thermal stability, exhibited significant improvements upon the addition of the synthesized SbB-g-GMA dual-functional compatibilizer compared to both the binary blends of PET/PS and the PET/PS/C30B nanocomposite. [ABSTRACT FROM AUTHOR]

Investigation of high-entropy alloys in form of bulk samples as well as thin films is currently one of the fastest growing areas in the study of metal alloys. In this paper, a bulk sample of FeNiCoCuCr high-entropy alloy ingot with equimolar composition is prepared by the laboratory arc melting method under an argon atmosphere and used as a source target for deposition of thin films on Si (111) single-crystalline substrates using a novel ionized jet deposition method. The morphology, chemical composition, and real crystalline structure of the target and the prepared layers were characterized by scanning electron microscopy, atomic force microscopy, energy-dispersive X-ray spectroscopy, and X-ray and neutron diffraction methods. Transfer coefficients characterizing the mass transport between the target and the grown film were calculated for each of the constituting metallic elements as the ratio of the atomic concentration found in the prepared film divided by its concentration in the deposition target. The dependence of the obtained transfer coefficients on the IJD acceleration voltage is discussed with respect to the main physical and geometric parameters of the deposition process, and their correlations with the cohesive energy of the elements forming the HEA are proposed. [ABSTRACT FROM AUTHOR]

We aim to develop new portable desktop tissue analysers (DTAs) to provide fast, low-cost, and precise test results for fast nanomechanical profiling of tumours. This paper will explain the reasoning for choosing indentation-type atomic force microscopy (IT-AFM) to reveal the functional details of cancer. Determining the subtype, cancer stage, and prognosis will be possible, which aids in choosing the best treatment. DTAs are based on fast IT-AFM at the size of a small box that can be made for a low budget compared to other clinical imaging tools. The DTAs can work in remote areas and all parts of the world. There are a number of direct benefits: First, it is no longer needed to wait a week for the pathology report as the test will only take 10 min. Second, it avoids the complicated steps of making histopathology slides and saves costs of labour. Third, computers and robots are more consistent, more reliable, and more economical than human workers which may result in fewer diagnostic errors. Fourth, the IT-AFM analysis is capable of distinguishing between various cancer subtypes. Fifth, the IT-AFM analysis could reveal new insights about why immunotherapy fails. Sixth, IT-AFM may provide new insights into the neoadjuvant treatment response. Seventh, the healthcare system saves money by reducing diagnostic backlogs. Eighth, the results are stored on a central server and can be accessed to develop strategies to prevent cancer. To bring the IT-AFM technology from the bench to the operation theatre, a fast IT-AFM sensor needs to be developed and integrated into the DTAs. [ABSTRACT FROM AUTHOR]

This paper summarizes the results of one of the first comprehensive laboratory studies that was conducted to evaluate the effects of adding different contents of recycled polyethylene terephthalate (rPETE) as a modifier to an asphalt binder on the rheological and mechanical properties of the modified binder as well as on the agglomeration behavior between the rPETE and asphalt binder at a multiscale level. The high-temperature and low-temperature performances of the modified binder were investigated at the macro-scale and compared with those of the unmodified binder using dynamic shear rheometer (DSR) and bending-beam rheometer (BBR) rheological tests, as well as asphalt binder cracking device (ABCD) testing. The nano-scale evaluation of the binder properties, including the surface roughness, bonding energy, and reduced modulus, was accomplished using atomic force microscopy (AFM). The results indicated that the addition of rPETE enhanced the high- and intermediate-temperature rheological properties of the modified PG 64-22 binder. The low-temperature rheological properties and resistance to cracking decreased slightly with increasing rPETE content in the asphalt binder. However, this reduction was not remarkable when adding 4%, 8%, and 10% rPETE contents. The asphalt binder modified with 4% rPETE had a low-temperature grade of −22, similar to that of the unmodified binder, indicating that 4% rPETE can be added to the binder to improve its high- and intermediate-temperature properties without reducing its resistance to low-temperature damage. The AFM tapping-mode results indicated that the inclusion of rPETE in the asphalt binder improved the stiffness properties of the modified binder as compared with those of the control asphalt binder. In addition, the rPETE-modified binders showed rougher surfaces than the control binder. The addition of rPETE to the binder increased the values of the reduced modulus and bonding energy compared with those of the control binder. [ABSTRACT FROM AUTHOR]

This paper studies the chemo-mechanics of cement beams containing polypropylene (PP) functionalized using ultraviolet (UV) irradiation. It is hypothesized that UV irradiation enhances the load transfer at the interface of cement and PP while facilitating the valorization of waste PP. In this study, we use UV-irradiated polypropylene (UVPP) plastic particles as an ingredient in cement paste, using the enhanced cement-UVPP interaction to improve the capacity for load transfer. Using atomic force microscopy based infrared spectroscopy (AFM-IR) on a UVPP-cement composite, we first show that the UV bombardment of PP promoted the formation of oxygen functional groups at the interface between UVPP and cement, indicating a possible increase in the affinity of the UVPP particles toward water and thus their hydrophilicity. This in turn is expected to enable the formation of bonds between the UVPP and cement, enabling stress transfer at the interface. We further show that this stress transfer increases the work-of-fracture, ductility, and mechanical energy absorption of the notched three-point bending cement-UVPP composite beam. This is accomplished when the two fracture surfaces that form during crack propagation are bridged by the UVPP-cement interaction. Since the ductility of these beams is size dependent, we performed fracture tests on two-dimensional (2D) geometrically scaled beams of four sizes. In addition to the mechanical improvements, this work forms the foundation for future work focused on reducing the carbon footprint of structures, since the UVPP replaces some of the cement and eliminates some of the plastic waste from landfills. [ABSTRACT FROM AUTHOR]

Conductive atomic force microscopy (c-AFM) can provide simultaneous maps of the topography and electrical current flow through materials with high spatial resolution and it is playing an increasingly important role in the characterization of novel materials that are being investigated for novel memory devices. However, noise in the form of stripe features often appear in c-AFM images, challenging the quantitative analysis of conduction or topographical information. To remove stripe noise without losing interesting information, as many as sixteen destriping methods are investigated in this paper, including three additional models that we propose based on the stripes characteristics, and thirteen state-of-the-art destriping methods. We have also designed a gradient stripe noise model and obtained a ground truth dataset consisting of 800 images, generated by rotating and cropping a clean image, and created a noisy image dataset by adding random intensities of simulated noise to the ground truth dataset. In addition to comparing the results of the stripe noise removal visually, we performed a quantitative image quality comparison using simulated datasets and 100 images with very different strengths of simulated noise. All results show that the Low-Rank Recovery method has the best performance and robustness for removing gradient stripe noise without losing useful information. Furthermore, a detailed performance comparison of Polynomial fitting and Low-Rank Recovery at different levels of real noise is presented. [ABSTRACT FROM AUTHOR]

Prostate cancer (PCa) is the second most common cancer. In this paper, the isolation and properties of exosomes as potential novel liquid biopsy markers for early PCa liquid biopsy diagnosis are investigated using two prostate human cell lines, i.e., benign (control) cell line RWPE1 and carcinoma cell line 22Rv1. Exosomes produced by both cell lines are characterised by various methods including nanoparticle-tracking analysis, dynamic light scattering, scanning electron microscopy and atomic force microscopy. In addition, surface plasmon resonance (SPR) is used to study three different receptors on the exosomal surface (CD63, CD81 and prostate-specific membrane antigen-PMSA), implementing monoclonal antibodies and identifying the type of glycans present on the surface of exosomes using lectins (glycan-recognising proteins). Electrochemical analysis is used to understand the interfacial properties of exosomes. The results indicate that cancerous exosomes are smaller, are produced at higher concentrations, and exhibit more nega tive zeta potential than the control exosomes. The SPR experiments confirm that negatively charged α-2,3- and α-2,6-sialic acid-containing glycans are found in greater abundance on carcinoma exosomes, whereas bisecting and branched glycans are more abundant in the control exosomes. The SPR results also show that a sandwich antibody/exosomes/lectins configuration could be constructed for effective glycoprofiling of exosomes as a novel liquid biopsy marker. [ABSTRACT FROM AUTHOR]

Multimodal imaging and spectroscopy like concurrent scanning transmission X-ray microscopy (STXM) and X-ray fluorescence (XRF) are highly desirable as they allow retrieving complementary information. This paper reports on the design, development, integration and field testing of a novel in situ atomic force microscopy (AFM) instrument for operation under high vacuum in a synchrotron soft X-ray microscopy STXM–XRF end-station. A combination of μXRF and AFM is demonstrated for the first time in the soft X-ray regime, with an outlook for the full XRF–STXM–AFM combination. [ABSTRACT FROM AUTHOR]

The cracking behavior of lignite during drying–wetting cycles impacts the efficiency of coal mining, underground coal gasification, and coalbed methane development. Lignite is known to have high water content, and it exhibits strong hydrophilic properties, resulting in a weak and rigid gel structure caused by water interactions with coal matrix molecules. Even at ambient temperatures, dehydration causes violent shrinkage of the lignite matrix and numerous fractures. Due to the shallow burial depth of lignite, it is often mined in open pits, and it often undergoes cycles of dehydration and rewetting in the open-air environment, resulting in significant changes to its physical structure and mechanical properties. Thus, a detailed characterization of this evolution process is necessary. In this study, lignite samples with different compositional properties were collected from the Shengli Coalfield in the Erlian Basin, and their physical structure and mechanical properties were characterized using nondestructive testing methods such as nuclear magnetic resonance, environmental scanning electron microscopy, X-ray computed tomography, and atomic force microscopy. The results provide insights into the impact of material composition on the syneresis behavior and destruction process of lignite. Upon removal of water from the coal matrix, rapid shrinkage occurs, resulting in the simultaneous formation of numerous fractures. Significant differences were observed in the contraction characteristics and fracture propagation patterns among the various lignite lithotypes. Xylite lignite exhibited the highest degree of contraction following dehydration, with the macropore reduction rate being the most significant. Matrix lignite showed a lower degree of syneresis compared to xylite lignite, while fusain-rich lignite demonstrated the weakest syneresis ability. The homogeneous xylite lignite shrinks as a whole after dehydration, and its fractures are long and straight, with good orientation. Fractures formed in the detrital humic groundmass of matrix lignite are short, convoluted, and poorly oriented. Fusain-rich lignite fractures are thin, and straight, with the best orientation. The expansion of fractures can cause geological disasters such as land subsidence, collapse, and landslides. Fusain hinders fractures' expansion and acts as a "skeleton" to support the lignite structure. The presence of fusain is advantageous to maintaining the steadiness of the lignite. The differential evolution of the physical structure of lignite during the drying–wetting cycles, which aids to avert and mitigate disasters linked to dehydration cracking in different lignite-related engineering geological fields, is discussed in this paper. [ABSTRACT FROM AUTHOR]

This paper presents a critical review on the measuring methods and parameters affecting nano-tribology in the context of nano-scale wear. Nano-scale wear phenomena play a crucial role in various industries, including micro/nano-systems, electronics, and biotechnology. The review begins by discussing the significance of nano-scale wear and its impact on device performance, lifespan, durability, energy efficiency, cost savings, and environmental sustainability. It then delves into the measuring methods employed to assess nano-scale wear, including scanning probe microscopy (SPM) techniques such as atomic force microscopy (AFM) and friction force microscopy (FFM). The capabilities of AFM and FFM in studying the roughness of surface, adhesion, friction, scratch, abrasion, and nano-scale material transfer are highlighted. Additionally, the review explores the parameters affecting nano-wear, such as lubrication strategies, stress levels, sliding velocity, and atomic-scale reactions. The article concludes by emphasizing the importance of advanced microscopy techniques in understanding tribological mechanisms at different scales, bridging the gap between macro and nano-tribology studies. [ABSTRACT FROM AUTHOR]

Poisson's ratio is the fundamental metric used to discuss the performance of any material when strained elastically. However, the methods of the determination of Poisson's ratio are not yet discussed well. The first purpose of this paper is to introduce the five kinds of typical experimental methods to measure Poisson's ratio of glasses, ceramics, and crystals. The second purpose is to discuss the experimental results on the variation of Poisson's ratio by composition, temperature, and pressure reviewed for various glasses, ceramics, and crystals, which are not yet reviewed. For example, in oxide glasses, the number of bridging oxygen atoms per glass-forming cation provides a straightforward estimation of network crosslinking using Poisson's ratio. In the structural-phase transition of crystals, Poisson's ratio shows remarkable temperature-dependence in the vicinity of a phase-transition temperature. The mechanism of these variations is discussed from physical and chemical points of view. The first-principles calculation of Poisson's ratio in the newly hypothesized compounds is also described, and its pressure-induced ductile–brittle transition is discussed. [ABSTRACT FROM AUTHOR]

In this paper, a dynamic model of reconstruction of the shear force g(t) in the Atomic Force Microscopy (AFM) cantilever tip-sample interaction is proposed. The interaction of the cone-shaped cantilever tip with the surface of the specimen (sample) is modeled by the damped Euler-Bernoulli beam equation ρA(x)utt +μ(x)ut+(r(x)uxx+κ(x)uxxt)xx=0, (x,t)∈(0,ℓ)x(0,T), subject to the following initial, u(x,0)=0, ut(x,0)=0 and boundary, u(0,t)=0, ux(0,t)=0, (r(x)uxx(x,t)+κ(x)uxxt)x=ℓ=M(t), (-(r(x)uxx+κ(x)uxxt)x)x=ℓ=g(t) conditions, where M(t):=2hcosθg(t)/π is the momentum generated by the transverse shear force g(t). For the reconstruction of g(t) the measured displacement v(t):=u(ℓ,t) is used as an additional data. The least square functional ... is introduced and an explicit gradient formula for the Fréchet derivative through the solution of the adjoint problem is derived. This allows to construct a gradient based numerical algorithm for the reconstructions of the shear force from noise free as well as from random noisy measured output v(t). Computational experiments show that the proposed algorithm is very fast and robust. This allows to develop a numerical "gadget" for computational experiments of generic AFMs. [ABSTRACT FROM AUTHOR]

Silicone elastomer coatings have shown successful fouling release ability in recent years. To further enhance the design of silicone coatings, it is necessary to fully understand the mechanisms that contribute to their performance. The objective of this study was to examine the relationship between the molecular weight of polydimethylsiloxane (PDMS) and antibioadhesion efficiency. PDMS-based coatings were prepared via a condensation reaction, with a controlled molecular weight ranging from 0.8 to 10 kg·mol−1. To evaluate changes in surface wettability and morphology, contact angle experiments and atomic force microscopy (AFM) were performed. Finally, the antibioadhesion and self-cleaning performance of PDMS coatings was carried out during in situ immersion in Lorient harbor for 12 months. Despite small variations in surface properties depending on the molecular weight, strong differences in the antibioadhesion performance were observed. According to the results, the best antibioadhesion efficiency was obtained for coatings with an Mn between 2 and 4 kg·mol−1 after 12 months. This paper provides for the first time the impact of the molecular weight of PDMS on antibioadhesion efficiency in a real marine environment. [ABSTRACT FROM AUTHOR]

Polymer materials are widely used in medicine due to their mechanical properties and biological inertness. When ion-plasma treatment is used on a polymer material, a carbonization process occurs in the surface nanolayer of the polymer sample. As a result, a surface carbonized nanolayer is formed, which has mechanical properties different from those of the substrate. This layer has good biocompatibility. The formation of a carbonized nanolayer on the surface of polymer implants makes it possible to reduce the body's reaction to a foreign body. Typically, to study the properties of a carbonized layer, flat polymer samples are used, which are treated with an ion flow perpendicular to the surface. But medical endoprostheses often have a curved surface, so ion-plasma treatment can occur at different angles to the surface. This paper presents the results of a study of the morphological and mechanical properties of a carbonized layer formed on a polyurethane surface. The dependence of these properties on the directional angle of the ion flow and its fluence has been established. To study the surface morphology and elastic properties, methods of atomic force microscopy and methods of elasticity theory were used. The strength properties of the carbonized layer were studied using a stretching device combined with a digital optical microscope. [ABSTRACT FROM AUTHOR]

This article covers selected properties of organic–inorganic thin films of hybrid perovskites with the summary formulas CH3NH3MI3, where M = Pb, Cd, Ge, Sn, Zn. The paper discusses not only the history, general structure, applications of perovskites and the basics of the theory of nonlinear optics, but also the results of experimental research on their structural, spectroscopic, and nonlinear optical properties. The samples used in all presented studies were prepared in the physical vapor deposition process by using co-deposition from two independent thermal sources containing the organic and inorganic parts of individual perovskites. Ultimately, thin layers with a thickness of the order of nanometers were obtained on glass and crystalline substrates. Their structural properties were characterized by atomic force microscopy imaging. Spectroscopic tests were used to confirm the tested films' transmission quality and determine previously unknown physical parameters, such as the absorption coefficient and refractive index. Experimental results of the nonlinear optical properties were obtained by studying the second and third harmonic generation processes and using initial sample polarization in the so-called Corona poling process. The obtained experimental results allowed us to determine the second- and third-order nonlinear optical susceptibility of the tested materials. [ABSTRACT FROM AUTHOR]

Reagentless molecular-imprinted polymer (MIP) electrochemical biosensors can offer the next generation of biosensing platforms for the detection of biomarkers owing to their simplicity, cost-efficacy, tunability, robustness, and accuracy. In this work, a novel combination of Prussian blue (PB), coated as an embedded redox probe on a gold working electrode (GWE), and a signal-off MIP assay has been proposed in an electrochemical format for the detection of troponin I (TnI) in biofluids. TnI is a variant exclusive to heart muscles, and its elevated level in the bloodstream is indicative of acute myocardial infarction (AMI). The proposed lab-manufactured PB/MIP electrochemical biosensor, consisting of a simple signal-off MIP assay and a PB redox probe embedded on the GWE surface, is the first of its kind that allows for reagentless, label-free, and single-step electrochemical biosensing of proteins. The preparation steps of the biosensor were fully characterized by cyclic voltammetry (CV), atomic force microscopy (AFM), and Raman spectroscopy. Finally, the performance of the optimized biosensor was investigated through the determination of various concentrations of TnI, ranging from 10 to 100 pg mL−1 within 5 min, in serum and plasma with limits of detection less than 3.6 pg mL−1, and evaluation of selectivity towards TnI using some relevant proteins that exist in biofluids with higher concentrations. [ABSTRACT FROM AUTHOR]

This paper studies the dynamics of an atomic force microscopy (AFM) cantilever that is considered to be operating under continuous viscoelastic surface contact with material profiles based on the modified nonlocal theory of elasticity. The contact between the cantilever's tip and the sample surface is modeled using a linear stiffness–damper pair and a lumped mass at the beam's free end. The higher-order partial differential equation (PDE) governing the AFM nanocantilever transverse motion and its associated higher-order boundary conditions (BCs) are derived employing extended Hamilton's principle based on the nonlinear nonlocal higher-order constitutive relation in Euler–Bernoulli beam model. The Galerkin's decomposition method is applied to discretize the higher-order PDE and BCs of motion into a set of ordinary differential equations (ODEs) via the mode summation technique using eigenfunctions (mode shapes) of a classic cantilever thin beam. Then, using state-space form of ODEs of motion the frequency analysis is performed based on the eigenvalues of vibration motion. The obtained results are validated with the literature works. The impact of various parameters including nonlocal nanoscale elasticity parameter, added point mass, contact stiffness and viscous damping factors and the specific position where the concentrated mass and the contact stiffness–damper pair are attached to the beam on the resonant frequencies of AFM cantilever is comprehensively investigated. Numerical simulations showed that the resonance frequencies of the AFM cantilever increase by increasing the value of nonlocal nanoscale parameter. Also, it was concluded that an increase in the nonlocal parameter and surface contact stiffness leads the AFM cantilever to be more stiffened. Moreover, it was seen that by increasing the position distance of lumped mass on the beam and contact spring–damper pair from the beam's fixed end, the resonant frequency reduction in the larger values of the surface contact stiffness is more noticeable. [ABSTRACT FROM AUTHOR]

The recent decade has seen a huge impact of nanotechnology in different sciences. In analytical chemistry, nanomaterials have been utilized for various purposes from sample preparation to detection. The impact of nanotechnology in analytical science is not limited to the improvement of analytical methodologies. Nanomaterials have been utilized for nanomaterials analysis as nanotools. Nanotools are used to investigate and work with materials at the nanoscale. Nanotechnology has also enabled new applications such as nanoscale tips used for topological microscopy in atomic force microscopy, scanning tunneling microscopy, and magnetic force microscopy. These techniques utilize nanotechnology to improve their efficiency. Furthermore, nanotechnology has enabled the construction of tweezers and robots in the nanoscale. These nano-enabled tools (nanotools) have been successfully utilized for nanoanalysis and nanomanipulation. Atomic force microscopy, scanning tunneling microscope, and magnetic force microscopy are not only meant to image nanostructured surfaces but also they are utilized for the manipulation of materials at the atomic and nanoscale. Nanotweezers, nanorobots, and laser tweezers using nanoapertures are also able to manipulate nano and microscale materials. This paper reviews the principles and application of the mentioned nano-enabled techniques as nanotools in analytical chemistry with a focus on nanomaterials nanoanalysis and nanomanipulation as nanoanalytes. [ABSTRACT FROM AUTHOR]

A potential source of particle contamination due to poorly maintained PECVD chamber condition forces to perform in situ dry cleaning also actively employed before the wet-cleaning chamber maintenance period. In this paper, we demonstrate the use of plasma process diagnostic sensors, optical emission spectroscope, and quadrupole mass spectrometer for in situ plasma monitoring of the dry-cleaning step. It is worthwhile to know the thin film residue on the chamber's inner wall, but it is difficult to collect the deposited thin film sample from the wall since the preparation of the sample from the equipment is impossible. To alleviate the concern, we prepared silicon wafer samples mounted on the chamber sidewall over the prolonged exposure of the SiO2 deposition process, and the collected sensory data were investigated under the dry-cleaning condition. The residue film obtained through the experiment was characterized by Fourier transform infrared, x-ray photoelectron spectroscopy, atomic force microscopy, and scanning electron microscopy. We found a useful insight into the chamber dry-cleaning end point detection application through residual gas analysis, and the results contribute to process engineers setting up the in situ dry-cleaning recipe to make sure that subsequent deposition can be consistently maintained. [ABSTRACT FROM AUTHOR]

SiC is an indirect bandgap semiconductor with material properties ideal for power electronics but not so much as an optical emitter. Meanwhile, gallium arsenide (GaAs) is a material known for high-performance optical devices due to its direct bandgap and carrier lifetime. Integrating GaAs with silicon carbide (SiC) can result in the best of both materials. However, integrating the two presents a significant challenge due to the large lattice mismatch between the two materials. In this paper, we investigate the growth of high-quality GaAs directly on 4H-SiC and on AlAs/4H-SiC substrates. The thin films were characterized using key techniques for structural and optical analyses, such as x-ray diffraction, atomic force microscopy, and photoluminescence (PL) spectroscopy. The 3D-island nature of growth of GaAs directly on SiC results in weak in-plane correlation with the substrate but high photoluminescence. This was demonstrated with an observed PL intensity comparable to the PL observed from a GaAs substrate with a similar buffer layer. Introduction of a thin AlAs nucleation layer results in improved wetting of the substrate, better in-plane correlation with substrate, and overall improved crystalline quality and is now under further study. [ABSTRACT FROM AUTHOR]

Molecular association of lipid membranes is an important tool to understand their biological functions. Engineered nano/microscopic lipid surface structures enable controlled surface properties such as adhesion, wetting and molecular recognition, correlated to the surface topography, molecular structure and interactions. In this work, patterned nanometer scale 2D lipidic channels from two cationic phospholipids, namely, 1,2-distearoyl-sn-glycero-3-ethylphosphocholine (EPC) and 1,2-dioleoyl-snglycero-3-ethylphosphocholine (EPCU) are reported along with the zwitter-ionic lipid 1,2-dipalmitoylsn-glycero-3-phosphatidylcholine (DPPC) as a reference. Atomic force microscopy was used to probe the exotic 2D lipidic channels formed on the mica substrate. Analyzing the isotherms comprising 2D surface pressure as a function of the mean molecular area provided insights into hydrocarbon chain ordering and packing, lateral compressibility/elasticity, and head group influence on that one leaflet of a bilayer. The condensed phase surface topography revealed 2D multiple-fold lipidic vesicles fused anisotropically into regular ordered channels of 30-50 nm height and 300-500 nm width. The results revealed condensation of the monolayer into higher ordered phases as a function of the chemical structure of the lipids. The chemical reactivity and electronic properties of the pure lipids and lipids in association with tryptophan amino acids were unravelled adopting density-functional theory (DFT) calculations. The packing and surface elastic properties of the lipid monolayers during interaction with tryptophan revealed phase separation in the surface architecture as a result of the occurrence of predominant electrostatic, hydrogen-bonding and hydrophobic interactions between the components, as revealed from the DFT results. [ABSTRACT FROM AUTHOR]

The synthesis of polyurethane elastomers with repair abilities and robust mechanical properties under mild conditions remain a great challenge. Numerous studies have shown that dynamic disulfide bonds are the important chemical chain unit of polyurethane with self-healing properties. Therefore, the synthesis of diols containing a disulfide bond chain unit is the key for achieving polyurethane with self-healing properties. In this study, three kinds of hydroxyl-capping diol fluorescent molecules containing disulfide were synthesized from 2,20-dithiobisbenzoic acid (DTSA) with glycol (EG), 1,4-butanediol (BDO) or 1,6-hexanediol (HDO) via esterification. The structures and properties of the synthesized aromatic disulfide diol and the derived disulfide-containing self-healing fluorescent polyurethane (SFPU) were characterized using proton nuclear magnetic resonance (¹H NMR and 13C NMR) spectroscopy, Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), atomic force microscopy (AFM), small-angle X-ray scattering (SAXS), dynamic mechanical analysis (DMA), and other techniques. The results demonstrated the successful synthesis of diols containing aromatic disulfide bonds. The self-healing rate of polyurethane elastomers, with aromatic disulfide diols introduced as hard segments, was approximately 61.50% at 20 1C. Polyurethane elastomers exhibited excellent mechanical properties and demonstrated fluorescence. These novel self-healing fluorescent polyurethane elastomers can be widely used in industries such as building, clothing, furniture, medical materials, armaments, and packaging. This research study will have some guiding significance in expanding the application of self-healing fluorescent polyurethane. [ABSTRACT FROM AUTHOR]

This paper describes different growth modes of AlN layers on micro-cone patterned c-sapphire substrates (μ-PSSs) using plasma-assisted molecular beam epitaxy. Ordered arrays of AlN nanoprisms and microrods were selectively grown on the tips of μ-PSS's microcones according to a bottom-up formation mechanism using sequential migration enhanced and metal-modulated epitaxy (MME) under metal-rich growth conditions at 820 °C. Transmission electron microscopy revealed structurally perfect AlN regions above the tips of the μ-PSSs, which initiate as inverted nanopyramids with {10 11 ¯ } side faces, evolving into hexagonal nanoprisms with orientations of {1 1 ¯ 00} and (0001) for side and top surfaces, respectively. The diameter and height of these ordered hexagonal nanoprisms, which have a 60% probability of nucleating, were about 1 μm. Long-term MME growth of these nanoprisms in both vertical and lateral directions led to the formation of AlN(0001) microrods with a maximum possible diameter of two micrometers and a height of up to 6 μm. Atomic force microscopy revealed a mixed step-flow and 2D nucleation growth mechanism for the flat tops of these AlN nanoprisms and microrods with an average surface roughness of 1–2 monolayers. Micro-Raman spectroscopy demonstrated narrow E2 (high) linewidths of 3.8 and 4.2 cm−1 for essentially stress-free AlN nanoprisms and microrods, respectively. [ABSTRACT FROM AUTHOR]