From Fourier Transform Infrared Spectroscopy Research Articles

Abstract A010: Biofluid-Ensemble Analysis through Multi-modal Spectroscopy (BEAMS): A deep learning architecture for rapid early-stage liquid biopsy cancer diagnostics

Abstract Introduction: Head and neck cancer (HNC) is one of the most common cancer types globally without an accessible rapid screening method. Conventional screening occurs at the clinician’s office, where grading and staging of the tumors are physically performed, and the clinician’s preliminary diagnosis is usually confirmed through laborious procedures of histology and CT/PET/MR scans. Patient’s quality of life and expected outcomes can be improved through early-stage screening, yet there is no existing technology on the market that tackles this dire need. As such, we propose a rapid liquid biopsy diagnostic platform empowered by deep learning algorithms that makes early-stage non-invasive screening possible. The platform utilizes the complementary vibrational spectral biomarkers information from Fourier Transform Infrared Spectroscopy (FTIR) and Raman spectroscopy. We coupled the techniques with two biofluids: saliva and plasma, which offered information on circulating and localized metabolites. Materials and Methods: The patient’s biofluid is first drop-casted on top of a substrate and air-dried at room temperature. Using an FTIR microscope or a Raman microscope, 25 spot measurements are made in a 5 by 5 grid pattern to produce a comprehensive scan of the sample. The measured spectra are subsequently fed into the deep learning framework to perform classification. The deep machine learning framework is composed of spectrum and subject-level models. Specifically, the spectrum-level model employs cascading convolutional layers to identify the prominent features within the spectrum. This is followed by a sequence of linear layers that further extract features from the convolutional layers and carry out binary classification. For each patient, preliminary classification results of the spectral level model are then evaluated on a per- modality basis across our four modalities (FTIR/Raman measurements made on saliva/plasma) where the patient is classified as positive if any of the modality models deem it so. This framework is applied to a cohort of 96 patients, with 36 non-cancerous patients, 28 early-stage patients, and 32 late-stage patients. Results and Discussion: Our model optimized for general cancer detection has a sensitivity of 91.7%, specificity of 77.8%, and accuracy of 86.5%. Late- stage cancer has proven to be less challenging to detect since our model optimized for late-stage cancer diagnosis has a sensitivity of 93.8%, a specificity of 83.3%, and an accuracy of 88.2%. Our best early-stage model has a sensitivity of 89.3%, a specificity of 69.4%, and an accuracy of 78.1%. Conclusions: Our proposed framework has demonstrated promising capability as the preliminary screening method for high-risk patients (e.g. tobacco users) while providing further interpretability of the deep learning model that is often characterized as a “black box”. The modular nature of our model structure offers substantial flexibility, enabling effective performance even when specific biofluids or spectroscopy modalities are unavailable. Citation Format: Kwan Lun Chiu, Antonio Guillen-Perez, Rebecca Mayer, Wesley Viner, Hanna Koster, Matthew Benson, Jeremy Rowe, Maria Navas-Moreno, Andrew Birkeland, Maria-Dolores Cano, J. Sebastián Gomez-Diaz, Randy Carney. Biofluid-Ensemble Analysis through Multi-modal Spectroscopy (BEAMS): A deep learning architecture for rapid early-stage liquid biopsy cancer diagnostics [abstract]. In: Proceedings of the AACR Special Conference: Liquid Biopsy: From Discovery to Clinical Implementation; 2024 Nov 13-16; San Diego, CA. Philadelphia (PA): AACR; Clin Cancer Res 2024;30(21_Suppl):Abstract nr A010.

A synthetic bis-triazine ring derivative based on ammonium phosphonate towards durable flame-retardant modification of cotton fabrics

A synthetic bis-triazine ring derivative based on ammonium phosphonate towards durable flame-retardant modification of cotton fabrics

Effect of Addition Amount of Ethylenediamine on Interlayer Nanochannels and the Separation Performance of Graphene Oxide Membranes.

In recent years, graphene oxide (GO)-based two-dimensional (2D) laminar membranes have attracted considerable attention because of their unique well-defined nanochannels and deliver a wide range of molecular separation properties and fundamentals. However, the practical application of 2D GO layered membranes suffers from instability in aqueous solutions as the interlayer d-spacing of GO membranes is prone to expansion caused by the hydration effect. In this study, the effects of the ethylenediamine (EDA) addition amount on the structure, crosslinking mechanism and separation performance of GO membranes were investigated systematically, and membrane performance was evaluated using water permeability and dye/salt rejection tests. The experimental results show that the amine groups of EDA chemically bond with the hydroxyl functional group (O=C-OH) of GO after intercalation, as evident from Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS). By further controlling the amount of the intercalated EDA, the as-prepared GO composite membranes show nanoscale-tuned d-spacing promising for downstream applications. In the demonstrated dye/salt nanofiltration scenario, the EDA intercalated and crosslinked GO membrane has enhanced permeability by over five times and a better dye rejection rate of over 96% compared with pure GO membranes. These findings highlight a facile strategy for controlling nanochannels by tuning the amounts of reactive intercalants.

Structural, micro-structural and physico-chemical studies of Polyvinylpyroledene (PVP) added Cobalt ferrite (CoFe2O4) nanoparticles

Structural, micro-structural and physico-chemical studies of Polyvinylpyroledene (PVP) added Cobalt ferrite (CoFe2O4) nanoparticles

Influence of germination time on free amino acids, phenolic compounds and γ-aminobutyric acid in pigeon pea (Cajanus cajan (L.) Huth) seeds

This research studied the influence of phytochemical compounds on the germination time of pigeon pea (Cajanus cajan (L.) Huth). Over the 72 hours germination period, the contents of total and most individual free amino acids, particularly histidine, showed substantial increases. The content of γ-aminobutyric acid (GABA) was also greatly increased, from 0.24 µg/g to 2.7 µg/g, representing a nearly ninefold increase. The total phenolic content (TPC) and total flavonoid content (TFC) were positively related with germination time, with TPC highest at 62.49 mg GAE/100 g DW at 72 h, and TFC increased from 18.87 mg RE/100 g DW to 30.05 mg RE/100g.DW at 72 hours. The contents of individual phenolic acids and flavonoids, such as, protocatechuic acid, p-coumaric acid, ferulic acid and rutin, experienced noticeable increases. However, vanillic and catechin were only detectable at 72 hours, respectively. Antioxidant capacity measured by DPPH and FRAP assays increased from 102.30 to 128.95 mgTE/100g DW and 694.13 to 836.93 mg FeSO4/100g DW mmol/g, respectively, and therefore highlighting the enhanced antioxidant potential of germinated pigeon pea. The results from Fourier-transform infrared spectroscopy (FTIR) supported these findings. The study emphasizes the potential of germination to enhance the phytochemical compounds of pigeon pea seeds.

Extended Cycle Life Pb-Ion Batteries with High Coulombic Efficiency Exceeding 99.96% from Al/Pb Bimetallic Eutectic Electrolyte

Following renewable energy development, batteries are the most crucial way to establish an energy storage system. In the past hundred years, lead-acid batteries have been widely applied in industrial and vehicle applications. Their low cost, simple manufacturing, and good safety can compete with lithium-ion batteries. However, some challenges still exist, e.g., poor low-temperature performance and short cycle life; aqueous solution is the reason that oxygen evolves from positive electrodes, resulting in positive active material detached from the electrode. Thus, developing novel lead-ion batteries to replace lead-acid batteries is a significant issue. In metal-ion batteries research, deep eutectic solvent (DES) has been well developed in recent years due to its high thermal stability and wide electrochemical window. Herein, a new Al/Pb bimetallic eutectic electrolyte (BEE) composed of aluminium perchlorate (Al(ClO4)3·9H2O), lead perchlorate (Pb(ClO4)2·3H2O), and succinonitrile (SN) with acetonitrile (ACN) as an additive, mixing in molar ratio. To realize the medium effect in this electrolyte, the BEE is compared with concentrated Pb(ClO4)2 aqueous solution. The ion conductivity, viscosity, and thermal stability depend on the metallic salt/SN ratio, and we proposed that the optimized molar ratio is 1:1:12:5. It exhibits outstanding thermal stability within − 50 to 50 °C. From Fourier-transform infrared spectroscopy (FTIR) spectrum analysis in BEE, the O-H stretching decreased, and the ClO4 - stretching band increased, compared to the concentrated Pb(ClO4)2 aqueous solution; it can be understood that O-H interaction between Pb2+ and ClO4 - is weakened; meanwhile, ClO4 - ions participated in first solvation shell. This variation reduces the desolvation energy of Pb2+ to facilitate smoother lead plating/stripping and enables better electrochemical performance. To validate the effect of the solvation structure variation, assembling the Pb/Pb symmetric cell and Pb/Platinum (Pt) asymmetric cell are essential methods. Pb/Pb cell maintains a stable voltage hysteresis of about 20 mV even cycling 2500 h at the current density of 0.5 mA cm-2, Pb/Pt cell under galvanostatic conditions successfully performs highly reversible Pb plating/stripping, achieved average coulombic efficiency (ACE) >99.96% in BEE for more than 1000 h at current density 0.5 mA cm-2. Furthermore, we utilize BEE in Na3V2(PO4)3(NVP) and natural graphite (NG) as cathode material; the reversible Pb2+ and ClO4 - (de-)intercalation are respectively observed in Pb/NVP and Pb/NG full cell, Pb/NVP cell exhibited long-term cycling stability with 80.95% capacity retention and 98.21% ACE after 600 cycles at a current density of 100 mA g-1, then Pb/NG cell remains high discharge voltage plateau (≈1.7V) with 72% capacity retention after 200 cycles at a current density of 100 mA g-1. Electrochemical impedance spectroscopy (EIS) of Pb/NVP in BEE-1:1:12:0 and 1:1:12:5 shows that adding the ACN additive can decrease the solution resistance (Rs) and charge transfer resistance (Rct) of the cell. Ex-situ X-ray photoelectron spectroscopy (XPS) was performed on the Pb surface at the charging state, observing that Al species are co-deposited, revealing the synergistic effect between Aluminium perchlorate and Lead perchlorate. From the ex-situ X-ray diffraction (XRD) patterns of cycled NVP and NG cathode at charge/discharge states, some irreversible variation of peak position occurred, indicating that ion (de-)intercalation after operation; these results demonstrate BEE performed bi-functional ion (Pb2+ and ClO4 -) intercalation phenomenon. To further confirm the Pb2+ dynamic in the NVP cathode at charge/discharge progress, the X-ray absorption spectroscopy (XAS) characterization was applied. The comparison of XANES spectra collected at the V K-edge, the XANES shift to lower energy during discharging, this exhibition is consistent with reduction reaction of V4+ to V3+, the EXAFS spectra show the local structure change of V-P/Na/Pb bonds. The EXAFS spectra at the Pb LIII-edge indicated that the Pb-O distance is shortened during discharging; the abovementioned results demonstrate the Pb2+ (de-)intercalation process in the NVP structure.In conclusion, this work proposed a novel bimetallic eutectic electrolyte for potential lead-ion batteries that enables stable Pb plating/stripping. The cycle-life and capacity retention of Pb/NVP and Pb/NG full-cell with BEE is significantly improved by adding acetonitrile (ACN) additive. The XAS characterization further confirmed the (de-)intercalation of Pb2+ in the NVP cathode. A stable, high-voltage, and high-capacity positive electrode is needed, allowing the reuse of secondary lead metal to be applied to next-generation energy storage. Figure 1

The phase behavior of skin-barrier lipids: A combined approach of experiments and simulations

Skin barrier function is localized in its outermost layer, the stratum corneum (SC), which is comprised of corneocyte cells embedded in an extracellular lipid matrix containing ceramides (CERs), cholesterol (CHOL), and free fatty acids (FFAs). The unique structure and composition of this lipid matrix are important for skin barrier function. In this study, experiments and molecular dynamics simulation were combined to investigate the structural properties and phase behavior of mixtures containing nonhydroxy sphingosine CER (CER NS), CHOL, and FFA. X-ray scattering for mixtures with varying CHOL levels revealed the presence of the 5.4nm short periodicity phase in the presence of CHOL. Bilayers in coarse-grained multilayer simulations of the same compositions contained domains with thicknesses of approximately 5.3 and 5.8nm that are associated with elevated levels, respectively, of CER sphingosine chains with CHOL, and CER acyl chains with FFA chains. The prevalence of the thicker domain increased with decreasing CHOL content. This might correspond to a phase with ∼5.8nm spacing observed by x-rays (other details unknown) in mixtures with lower CHOL content. Scissoring and stretching frequencies from Fourier transform infrared spectroscopy (FTIR) also indicate interaction between FFA and CER acyl chains and little interaction between CER acyl and CER sphingosine chains, which requires CER molecules to adopt a predominantly extended conformation. In the simulated systems, neighbor preferences of extended CER chains align more closely with the FTIR observations than those of CERs with hairpin ceramide chains. Both FTIR and atomistic simulations of reverse mapped multilayer membranes detect a hexagonal to fluid phase transition between 65 and 80°C. These results demonstrate the utility of a collaborative experimental and simulation effort in gaining a more comprehensive understanding of SC lipid membranes.

Exploring the peel ash of musa acuminate as a heterogeneous green catalyst for producing biodiesel from Niger oil: A sustainable and circular bio economic approach

Exploring the peel ash of musa acuminate as a heterogeneous green catalyst for producing biodiesel from Niger oil: A sustainable and circular bio economic approach

Investigation on the thermochemical characteristics, kinetics and evolved gases for typical kitchen waste pyrolysis

Investigation on the thermochemical characteristics, kinetics and evolved gases for typical kitchen waste pyrolysis

Antibacterial and sunlight-driven photocatalytic activity of graphene oxide conjugated CeO2 nanoparticles

This work focuses on the structural, morphological, optical, photocatalytic, antibacterial properties of pure CeO2 nanoparticles (NPs) and graphene oxide (GO) based CeO2 nanocomposites (GO-1/CeO2, GO-5/CeO2, GO-10/CeO2, GO-15/CeO2), synthesized using the sol–gel auto-combustion and subsequent sonication method, respectively. The single-phase cubic structure of CeO2 NPs was confirmed by Rietveld refined XRD, HRTEM, FTIR and Raman spectroscopy. The average crystallite size was calculated using Debye Scherrer formula and found to increase from 20 to 25 nm for CeO2 to GO-15/CeO2 samples, respectively. The related functional groups were observed from Fourier transform infrared (FTIR) spectroscopy, consistent with the outcomes of Raman spectroscopy. The optical band gap of each sample was calculated by using a Tauc plot, which was observed to decrease from 2.8 to 1.68 eV. The valence state of Ce (Ce3+ and Ce4+) was verified using X-ray photoelectron spectroscopy (XPS) for CeO2 and GO-10/CeO2. The poisonous methylene blue (MB) dye was used to evaluate the photocatalytic activity of each sample in direct sunlight. The GO-15/CeO2 nanocomposite showed the highest photocatalytic activity with rate constant (0.01633 min–1), and it degraded the MB dye molecules by 100% within 120 min. The high photocatalytic activity of this material for degrading MB dye establishes it as an outstanding candidate for wastewater treatment. Further, these nanocomposites also demonstrated excellent antimicrobial activity against Pseudomonas aeruginosa PAO1.

Black Rice Anthocyanins as An Effective Antioxidant of Inhibition of Oil Oxidative Based on Molecular Modification

This present work investigated the influence of black rice anthocyanins as antioxidants on the oxidation stability of oil. Malonic acid, succinic acid and succinic anhydride were grafted on black rice anthocyanins through acylation method to improve their antioxidant activity in oil. The results from fourier transform infrared spectroscopy (FTIR) showed new absorption peaks near 1744 cm -1 and 1514 cm -1 , which implied that malonic acid, succinic acid and succinic anhydride grafted on the -OH of glucoside and rutinoside through esterification reaction and resulted that the polarity of these were reduced. Total content of anthocyanin (TAC) decreased to 166. 3 mg/g, 163.7 mg/g and 150.2 mg/g, respectively after modification with succinic acid, malonic acid and succinic anhydride. Compared with native anthocyanins, the acylation of black rice anthocyanins partially reduced its antioxidant activity. In addition, DPPH clearance of molecular modified anthocyanins decreased to 62.6% (San-An). As revealed in the oil stability through the determination of primary oxidation products (PV) and secondary oxidation products (p-AV), Sa-An, Ma-An and San-An showed stronger antioxidant activity in Schaal oven accelerated oxidation test during 12 days than native black rice anthocyanin in both corn oil and flaxseed oil. Molecular modified black rice anthocyanins are expected to be used as colorants, antioxidants, etc. in oil-rich food.

DNA binding peptide CF-14 enhances bactericidal efficacy of eugenol/carvacrol nanoparticles to Escherichia coli.

To evaluate the bactericidal action of antimicrobial peptide CF-14, Eugenol (EU) and carvacrol (CAR) nanoparticles (NPs) less than 200nm were surface-modified with CF14, gaining approximately 200nm of EU-CF and CAR-CF NPs with swollen morphology. EU-CF and CAR-CF NPs were bactericidal to E. coli at dosage of 0.09% and 0.07% (v/v), respectively; while they were just bacteriostatic to Staphylococcus aureus at 0.10% and 0.08% (v/v). Spectral variations in bacterial carbohydrates (1185-900cm-1), lipids (3000-2800cm-1) and DNA (1500-1185cm-1) were obvious as evident from Fourier transform infrared spectroscopy (FTIR). A higher percentage of membrane damaged (non-revivable) E. coli than S. aureus was found, which indicated electrostatic interactions between Gram-negative E. coli with cationic CF conjugated NPs leading to DNA disintegration. Interestingly, EU-CF and CAR-CF NPs inhibited E. coli growth in orange juice without impacting flavour compounds.

Estimation of Carbon Content in High-Ash Coal Using Mid-Infrared Fourier-Transform Infrared Spectroscopy

The carbon content of different types of coal determines its utility in industries and thermal power generation. The most popular and widely used is the conventional method (ultimate analysis) to determine coal’s carbon content (C, wt.%), along with H, N, and S. In the present study, the authors attempted to analyze the carbon content (C in %) in coals via data from Fourier-transform infrared (FTIR) spectroscopy, which can be a promising alternative. As a reference, the carbon content in the coal samples, referred to as CCHNS (in wt.%), was determined from the ultimate analysis. The mid-infrared FTIR spectroscopic data were used to investigate the response of functional groups associated with carbon or its compounds, which were used to model and estimate the carbon content in coal samples (referred to as CFTIR, in wt.%). FTIR spectral signatures were utilized in specific zones (between wavenumbers 4000 and 400 cm−1) from a total of 18 coal samples from the Johilla coalfield, Umaria district, Madhya Pradesh, India. These 18 coal samples were used to produce 126 Coal+KBr pellets (at seven known dilution factors for each coal sample), and the spectral response (absorbance) from each pellet was recorded. For model development and validation, the training set and test set were formed using a 17:1 split (K-fold cross validation). The carbon content in the coal samples was modeled using the training set data by applying the piecewise linear regression method employing quasi-Newton (QN) with a breakpoint and least squares loss function. The model was validated using an independent test set. A pairwise comparison of estimates of carbon in the laboratory from the CHNS analyzer (CCHNS) and modeled carbon from FTIR data (CFTIR) exhibited a good correlation, relatively low error, and bias (coefficient of determination (R2) up to 0.93, RMSE of 23.71%, and MBE of −0.52%). Further, the significance tests for the mean and variance using the two-tailed t-test and F-test showed that no significant difference occurred between the pair of observed CCHNS and the model’s estimated CFTIR. For high-ash coals from the Johilla coalfield, the model presented here using mid-infrared FTIR spectroscopy data performs well. Thus, FTIR can potentially serve as an important method for quickly determining the carbon content of high-ash coals from various basins and can potentially be extended to soil and shale samples.

Influence of Salt Concentration on Alkaline Extracted Refined Kappa- carrageenan and Its Characterization

Kappaphycus alverazii remains as a predominant source of kappa-carrageenan which is farmed extensively in Indonesia, Philippines and South East Asia. The current research focuses on the influence of concentration of salts and approach to dialysis on properties of carrageenan. Carrageenan due to its pronounced gelling and viscosifying properties, has gained significant usage in the areas of food, cosmetics, textiles, pharmaceutics, biomedicine, and numerous others. The process of extraction was conducted in a hot, alkaline condition at 80 oC for a duration of 2 hours. The alkaline substance used was KCl with 2% and 4% concentration and solvent to seaweed ratio was 20:1.Further, the resultant extracted samples were subjected to dialysis to evaluate the effect of dialysis on the quality of carrageenan. The absorbance peak at 849 cm–1 from Fourier Transform Infrared-Spectroscopy (FTIR) at all extraction conditions indicated D-galactose-4 sulphate related to kappa carrageenan obtained with no traces of \(\mu\)-precursor. The study demonstrated that the concentration of salts and the approach of dialysis have influenced the quality of yield, viscosity, gel strength, moisture content and ash content for the extracted carrageenan, which remains ideal for commercial applications.

Crystallinity in polymer electrolyte membranes used in H2 generators: Degradation mechanism from the perspective of recycling

Crystallinity in polymer electrolyte membranes used in H2 generators: Degradation mechanism from the perspective of recycling

Cellulose acetate/silica composites: Physicochemical and biological characterization

Cellulose acetate/silica composites: Physicochemical and biological characterization

Hydrolytic and thermal stability of urea‐formaldehyde resins based on tannin and betaine bio‐fillers

AbstractIn this work, betaine (trimethyl glycine) and tannin (complex biomolecules of polyphenolic nature) were used as bio‐fillers. Urea‐formaldehyde (UF) resin with a molar ratio of formaldehyde versus urea (FA/U) of 0.8 was synthesized in situ with tannin and betaine as bio‐fillers, to obtain UF resin with reduced free FA content and increased hydrolytic and thermal stability by the principles of sustainability. The samples TUF (with tannin) and BUF (with betaine) were characterized by using X‐ray diffraction analysis (XRD), non‐isothermal thermogravimetric analysis (TGA), and differential thermal analysis (DTA), supported by data from Fourier Transform Infrared spectroscopy (FTIR) and Scanning electron microscopy (SEM). The percentage of free FA in modified BUF resin is 0.1%, while the percentage of free FA in tannin‐modified resin is 0.8%. The hydrolytic stability of the modified UF resins was determined by measuring the concentration of liberated FA in the modified UF resins, after acid hydrolysis. The modified BUF resin is hydrolytically more stable because the content of released FA is 3.6% compared to the modified TUF resin, where it was 7.4%. Based on the value for T5%, the more thermally stable resin is the modified TUF resin (T5% = 123.1°C), while the value of the T5% for the BUF resin is 83.1°C. This work showed how UF bio‐composite with reduced free FA content and increased hydrolytic and thermal stability can be obtained using tannin and betaine as bio‐fillers.

Lignin from Brewers' Spent Grain: Structural and Thermal Evaluations.

Lignocellulose is a renewable ubiquitous material that comprises cellulose, hemicellulose, and lignin. Lignin has been isolated from different lignocellulosic biomass via chemical treatments, but there has been little or no investigation carried out on the processing of lignin from brewers' spent grain (BSG) to the best of authors' knowledge. This material makes up 85% of the brewery industry's byproducts. Its high moisture content hastens its deterioration, which has posed a huge challenge to its preservation and transportation; this eventually causes environmental pollution. One of the methods of solving this environmental menace is the extraction of lignin as a precursor for carbon fiber production from this waste. This study considers the viability of sourcing lignin from BSG with the use of acid solutions at 100 °C. Structural and thermal analyses were carried out on extracted samples, and the results were compared with other biomass-soured lignin to assess the proficiency of this isolation technique. Wet BSG sourced from Nigeria Breweries (NB), Lagos, was washed and sun-dried for 7 days. Tetraoxosulphate (VI) (H2SO4), hydrochloric (HCl), and acetic acid, each of 10 M, were individually reacted with dried BSG at 100 °C for 3 h and designated as H2, HC, and AC lignin. The residue (lignin) was washed and dried for analysis. Wavenumber shift values from Fourier transform infrared spectroscopy (FTIR) show that intra- and intermolecular OH interactions in H2 lignin are the strongest and possess the highest magnitude of hydrogen-bond enthalpy (5.73 kCal/mol). The thermogravimetric analysis (TGA) results show that a higher lignin yield can be achieved when it is isolated from BSG, as 82.9, 79.3, and 70.2% were realized for H2, HC, and AC lignin. The highest size of ordered domains (0.0299 nm) displayed by H2 lignin from X-ray diffraction (XRD) informs that it has the greatest potential of forming nanofibers via electrospinning. The enthalpy of reaction values of 133.3, 126.6, and 114.1 J/g recorded for H2, HC, and AC lignin, respectively, from differential scanning calorimetry (DSC) results affirm that H2 lignin is the most thermally stable with the highest glass transition temperature (Tg = 107 °C).

Preparation of porous calcium carbonate biochar and its beryllium adsorption performance

Wastewater disposal from beryllium production has become a significant problem in the industry. Therefore, this paper designed porous calcium carbonate biochar (CC-LBC) using Na2CO3 and CaCl2 to modify the biochar innovatively, after which we understudied the Be(II) adsorption effect of CC-LBC at different concentrations. The results from Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), X-ray Photoelectron Spectroscopy (XPS), and other characterization analyses showed that when CC-LBC particles were immersed in the Be(II) waste liquid, several O elements accumulated because of its loose and porous structure, generating more beryllium precipitates on the surface of the adsorbent. According to kinetic data fitting, investigations also revealed that both physical and chemical reactions controlled CC-LBC/Be(II) adsorption process, indicating that the CC-LBC/Be(II) adsorption system is suitable for the intraparticle diffusion model. Furthermore, when the beryllium on activated carbon was desorbed by 10% NaOH, the desorption effect was above 80%, and the saturation adsorption capacity of CC-LBC for Be(II) was up to 55 mg/g. However, when the initial concentration of Be(II) was equal to 0.5–1 mg/L, the concentration of beryllium after treatment was lower than 10 μg/L, confirming that CC-LBC had a better selective adsorption performance for beryllium in the binary system.

Chemotaxonomy, biomechanics, and paleophysiology of Alethopteris ambigua and Neuropteris ovata var. simonii (Late Pennsylvanian, Canada). A chemometric approach

Medullosales was a highly diverse and ecologically differentiated group of plants that flourished in the Late Carboniferous and Early Permian tropical wetlands of Euramerica and China. Although the Medullosales have been extensively studied, some aspects of their life habits are still not fully understood. This study focuses on the relationships between chemical composition and biomechanical /physiological characteristics of the two largest-known frond segments of Alethopteris ambigua (45 cm long) and Neuropteris ovata var. simonii (65 cm long) from the Late Pennsylvanian of the Sydney Coalfield, Canada. Additionally, this study provides new data obtained from Fourier transform infrared spectroscopy (FTIR) analysis that, in conjunction with morphological features, could be used to efficiently distinguish species and genera of fossil plants. The density of the different frond parts is calculated using a 3D multivariate model derived from FTIR data. Tensile strength, tensile modulus of elasticity, flexural stiffness, and leaf mass per area for the different frond parts are estimated using trait relationships linking density and structural properties established for modern plant-leaf tissues. Key results include the cognition of continuous variation of geomacromolecular compounds throughout the different-order rachises and pinnules from proximal to distal frond sections. In the proposed, theoretical fronds, these diagenetically-modified biomacromolecules would represent tannin-, lignin-, and resin-related compounds. Overall, pinnules and rachises of A. ambigua are characterized by high contents of aliphatic-rich structures, whereas those of N. ovata are mostly aromatic in composition. The chemical composition of the two fronds is hierarchically partitioned, indicating density dependence on the frond parts. This is reflected in the metabolic construction costs that, in the two species, differ significantly among pinnules and rachises. These results indicate “flexibility” of resource allocation, resulting into two different, architectural frond designs. The costs of building harder, stiffer, and more expensive pinnules in the N. ovata frond are compensated for by the metabolically inexpensive rachises. The opposite holds for the A. ambigua frond, i.e., relatively cheaper pinnules and more expensive rachises. This reveals the complexity of the biomechanical and physiological strategies employed by these two taxa to construct mechanically resistant and physiologically efficient, longer-lived fronds. Results suggest that these plants were likely stress-tolerant and opportunistic colonizers that dominated eutrophic habitats, which were typical of some tropical ecosystems of the Late Pennsylvanian.