Direct Transformation Research Articles

A calibration method for telecentric line-scan cameras with an enhanced dynamic imaging model and initial estimates derived from direct linear transformation

This study presents a calibration method for telecentric line-scan cameras, incorporating a dynamic imaging model and initial estimates derived from direct linear transformation. The enhanced dynamic imaging model includes an inclination parameter instead of velocities in three orthogonal spatial directions. It is applicable to any direction of motion, considers lens distortion, and accommodates the line sensor at an arbitrary position relative to the optical axis. Employing the enhanced camera model, the initial values of telecentric line-scan camera parameters are determined derived from direct linear transformation. Sensitivity of our method with respect to the noise level of image points and the number of pattern planes are assessed through numerical simulations, while effectiveness and robustness are validated through experiments using real-world data, achieving a reprojection error of 0.6386 pixels and a standard deviation of 0.0160 pixels. The versatility of the proposed method can be extended to measurement applications utilizing flatbed scanners.

Improving ductility and strength of high-entropy alloy [formula omitted] via multi-directional forging and annealing

A dual-phase high-entropy alloy Fe50Mn30Co10Cr10 is treated via multi-directional forging (MDF) and subsequent annealing at 600°C–1000°C. Different microstructures with totally different grain sizes and phase ratios are obtained. The MDF increases yield strength and ultimate tensile strength at the expense of ductility. Via annealing the MDF-processed alloy at 1000°C, the full recrystallized sample yields a excellent combination of high strength and good ductility due to the grain boundary strengthening, transformation-induced plasticity and twinning-induced plasticity. The yield strength, ultimate tensile strength and elongation at failure are 16.2%, 14.2% and 35.3% than those of the as-cast sample. The postmortem characterizations of this annealed sample show strong 〈111〉 texture in the austenite phase along the loading direction and intense martensite transformation with the gradually disappearance of the annealing twins.

Deprotective Lossen rearrangement: a direct and general transformation of Nms-amides to unsymmetrical ureas.

Ureas stand out as potent pharmacophores in drug development, rendering them a prime focus for synthesis. Herein, we present an appealing entry point for urea synthesis from protected amines (Nms-amides) and relying on a Lossen-type rearrangement process as an elegant example of deprotective functionalisation. The method developed exhibits an exceptionally broad tolerance towards various protected amines, encompassing numerous drug derivatives, and delivers high reaction yields.

Tandem Pt/TiO2 and Fe3C catalysts for direct transformation of CO2 to light hydrocarbons under high space velocity

CO2 hydrogenation to hydrocarbons under high space velocity is crucial for industrial applications, but traditional Fe-based catalysts often suffer from the low activity and poor stability. Herein, we report a new tandem catalyst system combining Pt/TiO2 catalysts with Fe3C catalysts for the direct conversion of CO2 into C2-C4 hydrocarbons under high space velocity. The Pt/TiO2 component promotes *CO intermediate production with an enhanced Reverse Water-Gas Shift (RWGS) reaction efficiency, providing a highly reactive species for the Fe3C catalyst to achieve Fischer-Tropsch synthesis (FTS). By maximizing the contact interface between the Pt/TiO2 and Fe-based components through a granule mixing configuration, we achieve significant enhancements in both CO2 conversion rate (24.0 %) and C2-C4 hydrocarbons selectivity (51.1 %) under the gaseous hourly space velocity (GHSV) of 100000 mL gcat−1h−1. Besides, excellent stability is achieved by the tandem catalysts with continuous catalysis for up to 80 h without significant decrease in activity. Through modulation of the reduction states of iron oxide, we effectively tune the composition of Fe-based catalyst, thereby tailoring the product distribution. Through this work, we not only offer a promising avenue for reducing CO2 for efficient CO2 utilization but also highlight the importance of catalyst design in advancing sustainable chemical synthesis.

Green directional conversion of food waste into glycerol in a two-step differentiation enzymolysis and facultative fermentation using Saccharomyces cerevisiae: Performance assessment and mechanism

Valorization of food waste into high value-added glycerol was designed and prepared via directional green transformation using multi-enzymolysis saccharification coupled facultative fermentation by Saccharomyces cerevisiae. The optimal conditions for the first step of multienzyme hydrolysis and the second step of facultative fermentation were 55 °C and pH 5.0 for 6 h, 30 °C and pH 7.0 for 70 h, respectively. The glycerol yield efficiency and kinetic rate constant were 73.6 % (w/w) and 0.681 h−1 for dry component of food waste, while the other 27.4 % was utilized as the growth energy substrate. The key points of transformation were the synergistic directed enzymolysis to produce 3 % glycerol and 95 % reducing sugars. Furthermore, the reducing sugars were converted into glycerol by switch the metabolic pathway from ethanol into glycerol through the quantitative expression of functional gpd1 and gpp2 genes activated GPD and GPP enzymatic activity and synchronous inhibition of adh gene for glycerol production with Na2SO3 regulation. The economic income was 135.52 USD/ton for converting 80 % water content of kitchen waste into glycerol. This finding provided an economic value-added approach to produce high-value glycerol for cost-effective recycling of food waste using commercial yeast.

Visible Light Promoted Site-Specific Functionalization of α-Acyloxy Carboxamides: Unlocking a Forbidden Chemical Space in the Passerini Reaction.

The facile generation of the α-acyloxy carboxamide radical is hereby reported for the first time, utilizing a photoredox catalyzed reaction of Passerini adducts synthesized using a 4-formyl-1,4-dihydropyridine as the carbonyl component. This radical effectively engages in a Giese reaction with a range of olefins, ultimately leading to the synthesis of novel Passerini-derived products not previously amenable to direct aldehyde-based transformations. Consequently, the resulting strategy, developed both in batch and in flow, offers a promising opportunity to expand the chemical space accessible through the Passerini reaction, virtually incorporating "impossible" aldehydes.

First-Principles Analysis of the Effects of Halogen Variation on the Properties of Lead-Free Novel Perovskites AlGeX3 (X = F, Cl, Br, and I).

To commercialize optoelectronic products and perovskite-based solar cells, nontoxic inorganic cubic metal halide perovskites have gained popularity. This study presents the structural, mechanical, electronic, and optical properties of novel lead-free metal cubic halide perovskites AlGeX3 (X = F, Cl, Br, and I) using the first-principles Density Functional Theory (DFT) approach. The verification of the mechanical stability of all compounds is conducted through Born stability criteria and formation energy. All of the compounds in the elastic investigations exhibit anisotropy, ductility, and elastic stability. The electronic band structures estimated by HSE06 and GGA-PBE functional demonstrate indirect to direct band gap transformation after substituting the halide F with the halides Cl, Br, and I. The tunability of halide-dependent energy bandgaps and the underestimation of energy band gaps are also noticed for the studied compounds by comparing the results obtained from the GGA-PBE functional and HSE06 investigations. The origins of bandgap transformation as well as halide-dependent energy gap modulation are explained by both the partial and total density of states (PDOS and TDOS). The results presented here suggest that all the compounds show low reflectivity, a high absorption coefficient, and also high optical conductivity in the visible and UV regions, making these materials suitable for multijunctional solar cells. Also, these materials have a greater impact on other optoelectronic device applications. Compared to other compounds, the optical investigation reported here demonstrates that AlGeI3 exhibits excellent optical conductivity and absorption in the visible region.

(Invited) Plasma Reforming of Liquid Hydrocarbons

Engineering systems that more sustainably use our natural resources is central to both reducing the risks associated with CO2 emissions and making the long-term transition to a more circular, sustainable, and electrified economy. In particular, developing electrically driven technologies to leverage the energy density of liquids to produce clean fuels, e.g., H2, without making CO2, could be game changing. Here, we investigate the potential of directly exciting plasmas in liquid hydrocarbons to create multi-phase reaction environments, i.e., environments where plasma (ionized gas), H2, gaseous and liquid hydrocarbons, and solid carbon are all present simultaneously, to produce H2, unsaturated C2s, and carbon. The ultimate target is direct transformation of liquid hydrocarbons to gaseous H2 and solid, easy-to-separate carbon using electricity that can be provided from any source and/or points of use.This talk will focus on our recent experiments to strike and sustain low and high frequency plasma discharges in liquid hydrocarbon jets to simultaneously generate gaseous H2, C2s, and solid carbon at high rates. Preliminary experiments show that (i) input energy is not wasted in simply vaporizing the liquid - so the system’s specific energy input preferentially drives hydrocarbon cracking; (ii) discharge drive frequency and plasma space time have a big effect on the H2 specific energy requirement (SER) and H2 generation rate, respectively; (iii) feedstock chemistry affects the H2 and C2 products observed; (iv) carbon particulates rapidly form in the liquid hydrocarbon, but they can be separated easily; and (v) the SER for H2 production is 25-30 kWhr/kg, roughly two times less than water electrolysis in practice (60 kWhr/kg). Hydrocarbon conversion, reaction rates, and characterization of the plasma (OES, high speed imaging), gas (MS), liquid (GC/MS), and solid phase (SEM, Raman) products as a function of plasma operating conditions (high and low AC drive frequency; liquid-plasma contact time) and hydrocarbon source will be discussed.

Homologation of Ketones: Direct Transformation of Alkyl Ketones to Aryl Ketones via Photoredox Catalyzed Deacylation-Aroylation Sequence.

Ketones, as essential functional group skeletons, have garnered significant interest due to their diverse transformations. Herein, we describe a versatile photoredox catalyzed deacylation-aroylation strategy that enables the direct transformation of alkyl ketones to aryl ketones. This process involves photoredox deacylation of dihydroquinazolinones derived from alkyl ketones to generate alkyl radicals, followed by subsequent NHC-catalyzed or NHC-mediated radical aroylation.

Direct transformation of rice straw to electricity and hydrogen by a single yeast strain: Performance and mechanism

Lignocellulosic waste is one of the most abundant renewable energy sources. However, pretreatment or complex microbial consortia are usually required for the biological transformation into energy products. This study demonstrates the direct transformation of raw rice straw biomass into electricity and hydrogen without any pretreatment by employing a single yeast strain, Cystobasidium slooffiae JSUX1, in microbial fuel cells (MFCs). The yeast-MFCs exhibit a maximum power density of 28.56 ± 2.54 mW/m2 with simultaneous production of hydrogen gas (4.9 ± 0.52 L/m3) from raw straw. Further analysis reveals that enzymes secreted by the yeast strain degraded rice straw into sugars or organic acids, serving as fuel for electricity and hydrogen production. In addition, humic acid (HA) and Fe-HA derived from biomass consumption serve as electron mediators for extracellular electron transfer (EET) in MFCs. This study demonstrates the power of the yeast strain for renewable energy recovery from straw, diversifying the toolbox for the lignocellulose industry.

A new method with C-means segmentation for non-uniform image coordinate system definition in panoramic imaging employing Ladybug2 camera

A panorama ensures a stunning wide-angle field of view up to 360° representation of a scene, exceeding the limits of a normal photograph. Panoramic cameras satisfy the single-viewpoint characteristic. There are several types of panoramic cameras for 360-degree imaging. Multi-camera panoramic imaging systems pose a difficulty in obtaining a single projection center for the cameras. In a variety of practical implementations of panoramic cameras, it is possible to calculate three-dimensional coordinates from a panoramic image, especially using the Direct Linear Transformation (DLT) method. In this study, not only a defining method of the non-uniform image coordinate system is presented by utilizing the C-Means algorithm for a single panoramic image, captured with a Ladybug2 panoramic camera in a panoramic calibration room but also the use of an elliptical panoramic projection coordinate system is defined by the Singular Value Decomposition method in a panoramic view. The results of the suggested method have been compared with the DLT algorithm for a single panoramic image which defined a conventional photogrammetric image coordinate system. It has been observed that the proposed method provides more accurate results for the 3D coordinate definition.

On accurate calculations of equilibrium H/D fractionations at super-cold conditions (≤200 K) I: Full Partition Function Ratio (FPFR) vs. Path Integral Monte Carlo (PIMC)

Accurate estimations of Hydrogen/Deuterium (H/D) isotope effects have been a long-standing problem since the beginning of stable isotope geochemistry, primarily due to their strong nuclear quantum effects (NQEs). Currently, the D/H ratio plays a key role in deciphering the origin and evolution of water ice and organics in the solar system. Additionally, the Big-bang origin of Deuterium necessitates that the observed D/H variations be linked to isotope exchange reactions, such as HD + H2O ↔ H2 + HDO. Therefore, an accurate benchmark dataset describing the equilibrium H/D isotope fractionations at low temperatures (≤ 200 K) is essential for interpreting rapidly accumulating astrochemical observation data. In this study, we implemented and compared two methods developed for evaluating the NQEs of H/D isotopes: 1) the Full Partition Function Ratio (FPFR) method and 2) the Path Integral Monte Carlo (PIMC) method. Both were assessed for their accuracy and efficiency in estimating equilibrium isotope effects (EIEs) using 10 common interstellar small molecules (H2, HF, HCl, HCN, HNC, H2O, H2S, NH3, HCHO, and CH4) as examples. Most of them are calculated at high precision for the first time. For the FPFR method, several higher-order corrections to the Urey-Bigeleisen-Mayer model were considered, including anharmonicity, quantum mechanical rotation with nuclear-spin statistics, and corrections to the Born-Oppenheimer approximation. For the PIMC method, four different actions related to the thermal density matrix are used. These include the primitive and three fourth-order actions (Takahashi and Imada, Suzuki-Chin and Chin approximations), based on the direct scaled-coordinates transformation. Three main conclusions are obtained: 1) Under the framework of Born-Oppenheimer approximation, the PIMC method holds the same and even slightly better accuracy (more comprehensive descriptions of quantum anharmonicities) in estimating EIEs for H/D isotopes as the FPFR method. However, both methods suffer from the neglection of the DBOC when using the Born-Oppenheimer potential energy surfaces. For the PIMC method, additional corrections for particle distinguishability must be considered when nuclear spin statistics exhibit its effects at low temperatures (e.g., < 160 K for H2). 2) Among the four actions, three fourth-order actions show better convergence and efficiency (2.2 to 26.5 times speedups at 50 K) than the primitive action, making them superior candidates for PIMC simulations at super-cold (≤ 200 K) conditions. 3) A combination of accurate potential energy surface with the PIMC method serves as an alternative way for theoretical estimations of H/D isotope effects.

Best Scanline Determination of Pushbroom Images for a Direct Object to Image Space Transformation Using Multilayer Perceptron

Working with pushbroom imagery in photogrammetry and remote sensing presents a fundamental challenge in object-to-image space transformation. For this transformation, accurate estimation of Exterior Orientation Parameters (EOPs) for each scanline is required. To tackle this challenge, Best Scanline Search or Determination (BSS/BSD) methods have been developed. However, the current BSS/BSD methods are not efficient for real-time applications due to their complex procedures and interpolations. This paper introduces a new non-iterative BSD method specifically designed for line-type pushbroom images. The method involves simulating a pair of sets of points, Simulated Control Points (SCOPs), and Simulated Check Points (SCPs), to train and test a Multilayer Perceptron (MLP) model. The model establishes a strong relationship between object and image spaces, enabling a direct transformation and determination of best scanlines. This proposed method does not rely on the Collinearity Equation (CE) or iterative search. After training, the MLP model is applied to the SCPs for accuracy assessment. The proposed method is tested on ten images with diverse landscapes captured by eight sensors, exploiting five million SCPs per image for statistical assessments. The Root Mean Square Error (RMSE) values range between 0.001 and 0.015 pixels across ten images, demonstrating the capability of achieving the desired sub-pixel accuracy within a few seconds. The proposed method is compared with conventional and state-of-the-art BSS/BSD methods, indicating its higher applicability regarding accuracy and computational efficiency. These results position the proposed BSD method as a practical solution for transforming object-to-image space, especially for real-time applications.

Direct Upcycling of Degraded LiCoO2 Material Toward High‐Performance Single‐Crystal NCM Cathode

AbstractThe growing volume of spent lithium‐ion batteries (LIBs) with degraded LiCoO2 (D‐LCO) cathodes is arising as an environmental concern as well as a waste of strategic resources. Current recycling strategies for D‐LCO materials primarily focus on metal extractions (Li and Co), which produce large quantities of wastewater and waste residues and consume substantial amounts of energy. Inspiringly, the rapid proliferation of electric vehicles has catalyzed the ever‐increasing production of LIBs with ternary layered oxides as the prevalent cathode materials. Herein, this work reports a simple, green, and economic upcycling strategy for direct transformation of D‐LCO into high‐performance single‐crystal LiNi1/3Co1/3Mn1/3O2 (NCM111) cathode materials. By simultaneous lithium replenishment, particle size reduction, and chemical composition engineering in the upcycling process, the NCM111 product delivers a high specific capacity (159.0 mAh g−1 at 0.1 C) and an excellent cycling stability (82.1% retention after 200 cycles at 1 C), outperforming those of commercial materials. This work highlights the immense potential of upcycling strategies in mitigating the environmental ramifications of spent LIBs and paves the way for the sustainable development of LIBs industry.

Bulky Alkyl Substituents Enhance the Photocatalytic Activity of Pyridine-Based Donor-Acceptor Molecules in the Direct Reductive Cleavage of the C-Br Bond of Aliphatic Bromides.

We report new pyridine-based donor-acceptor (D-A) molecules that enable the direct reductive transformation of a variety of secondary and tertiary aliphatic bromides. A series of experimental and theoretical results suggested that the D-A molecules promote direct C-Br bond cleavage triggered by the excitation of the complex between the catalyst and the aliphatic bromide and that the alkyl groups significantly contribute to the stabilization of the complex, which improves the efficiency of its excitation.

High temperature oxidation regime transitions in hafnium carbide

AbstractUnderstanding the oxidation behavior of hafnium carbide is crucial to its application in extreme environments. In this work, the transition in high‐temperature oxidation kinetics regimes in hafnium carbide is explained based on phase equilibria considerations supported by observed changes in oxide scale microstructure evolution associated with different transformation pathways. Below, a composition‐dependent critical temperature and oxygen pressure, hafnium carbide first transforms to an amorphous material with nominal composition HfO2C followed by phase separation into carbon and hafnia domains. Subsequently, gaseous transport through a nanometric pore network formed by oxidative removal of phase‐separated carbon becomes rate‐limiting. Above this critical point, the oxidation sequence involves a direct transformation from hafnium carbide to hafnia and gaseous products, leading to dissimilar scale morphologies responsible for the reported transition from gaseous to solid‐state diffusion‐limited oxidation regimes at ultra‐high temperatures.

Calorimetric and Volumetric Studies of Dislocations During Martensitic Transformations in Shape Memory TiNi Alloy

Based on the use of appropriate approaches, methods and results of the analysis of a number of topical problems of physical materials science, an in-depth analysis has been done of calorimetric and volumetric data for direct, reverse and deformation martensitic transformations in a nanostructured Ti49.3Ni50.7 shape memory alloy obtained by cold rolling with simultaneous action of pulsed high-density current. For the first time, by applying a new technique for processing calorimetric spectra (peaks), the staging and “kinetics” of changes in heat content, as well as thermal effects (enthalpies of individual stages) during direct and reverse martensitic transformations during cooling or heating of samples at a constant rate (3 × K/ min) in the range 170–370 K has been done. It is shown, by processing volumetric data, using theoretical values of the dislocation density and elements of the classical theory of dislocations, that in the Ti49.3Ni50.7 shape memory alloy subjected to cold deformation accompanied by the action of a pulsed current, a deformation martensitic transformation occurs, leading to a positive volume effect (∆V/V) ≈ 3 × 10–3), which can be largely due to dislocations. It is shown, by applying the theoretical values of the dislocation density and elements of the classical theory of dislocations, that the possible contributions of dislocations to the enthalpies of direct and reverse martensitic transformations (in the Ti49.3Ni50.7 alloy) can and should be significantly lower in absolute value, but opposite in sign to the observed enthalpies of direct and reverse martensitic transformation in a given alloy. It is shown that the physics of the processes under consideration is contained to a certain extent in scientific discoveries No. 239 “The phenomenon of thermoelastic equilibrium during phase transformations of the martensitic type – the Kurdyumov effect” and No. 339 “The phenomenon of the formation of non-equilibrium grain boundaries in polycrystals when they absorb lattice dislocations”.

Laser-Printed All-Carbon Responsive Material and Soft Robot.

Responsive materials and actuators are the basis for the development of various leading-edge technologies but have so far mostly been designed based on polymers, incurring key limitations related to sensitivity and environmental tolerance. This work reports a new responsive material, laser-printed carbon film (LPCF), produced via direct laser transformation of a liquid organic precursor and consists of graphitic and amorphous carbons. The high activity of amorphous carbon combined with the dual-gradient structure enables the LPCF to have a actuation speed of 9400°s-1 in response to the stimulus of organic vapor. LPCF exhibits a conductivity of 950Sm-1 and excellent resistance to various extreme environmental conditions, which are unachievable for polymer-based materials. Additionally, an LPCF-based all-carbon soft robot that can mimic the complex continuous backward somersaulting motions without manual intervention is constructed. The locomotion velocity of the robot reaches a value of 1.19BLs-1, which is almost one to two orders of magnitude faster than that of reported soft robots. This work not only offers a new paradigm for highly responsive materials but also provides a great design and engineering example for the next generation of biomimetic robots with life-like performance.

Adsorption and dissociation of NO on gold–palladium alloy clusters: A density functional theory study

Alloy nanoclusters often exhibit distinctive and exceptional performance, making them especially appealing as catalysts. In this study, the adsorption and dissociation of NO on AumPdn (m + n = 8) clusters was studied using density functional theory (DFT). The most stable structures of AumPdn (m + n = 8) clusters were reported by the CALYPSO search screening program and DFT geometric optimization. The binding energy and bond critical point (BCP) analysis show that alloying could lead to a more compact structure and relatively stronger stability. Molecular electrostatic potential (MESP) analysis revealed that the optimal site for the adsorption of the NO molecule on AumPdn (m + n = 8) clusters was at the top site, with Pd atoms being the preferred choice. Projected density of states (PDOS) calculations demonstrate that the d-band center of the Au5Pd3 cluster was closest to the Fermi level, enhancing the interaction between the cluster surface and adsorbed molecules. The activation energy of NO dissociation on the Au5Pd3 surface is the lowest at 0.48 eV. These findings indicate that the Au5Pd3 nano-alloy cluster shows promise as an effective catalyst in the direct transformation of NO into non-toxic substances.

Simple-by-design approach for production of stabilizer-free cubosomes from phosphatidylglycerol and docosahexaenoic acid monoacylglycerol

Docosahexaenoic acid monoacylglycerol represents a promising lipid constituent in the development of drug nanocarriers owing to its amphiphilicity and the beneficial health effects of this docosahexaenoic acid precursor in various disorders including cancer and inflammatory diseases. Here, we describe the formation and characterization of simple-by-design and stabilizer-free lamellar and non-lamellar crystalline nanoparticles (vesicles and cubosomes, respectively) from binary mixtures of docosahexaenoic acid monoacylglycerol and phosphatidylglycerol, which is a ubiquitous amphiphilic component present in biological systems. At the physiological temperature of 37 °C, these single amphiphilic components tend to exhibit inverse hexagonal and lamellar liquid crystalline phases, respectively, on exposure to excess water. They can also be combined and dispersed in excess water by employing a high-energy emulsification method (by means of ultrasonication) to produce through an electrostatic stabilization mechanism colloidally stable nanodispersions. A colloidal transformation from vesicles to cubosomes was detected with increasing MAG-DHA content. Through use of synchrotron small-angle X-ray scattering, cryo-transmission electron microscopy, and nanoparticle tracking analysis, we report on the structural and morphological features, and size characteristics of these nanodispersions. Depending on the lipid composition, their internal liquid crystalline architectures were spanning from a lamellar (Lα) phase to biphasic features of coexisting inverse bicontinuous (Q2) cubic Pn3m and Im3m phases. Thus, a direct colloidal vesicle-cubosome transformation was detected by augmenting the concentration of docosahexaenoic acid monoacylglycerol. The produced cubosomes were thermally stable within the investigated temperature range of 5–60 °C. Collectively, our findings contribute to understanding of the imperative steps for production of stabilizer-free cubosomes from biocompatible lipids through a simple-by-design approach. We also discuss the potential therapeutic use and future implications for development of next-generation of multifunctional vesicles and cubosomes for co-delivery of docosahexaenoic acid and drugs in treatment of diseases.