Loading Of Substrate Research Articles

One-pot direct conversion of passion fruit hull into 5‑hydroxymethylfurfural catalysed by halogenated metal ionic liquids and organic acids

Biomass serves as a crucial source of renewable energy and potential raw materials for synthesizing various value-added chemicals. This study explored the direct conversion of the cellulose of passion fruit shells into 5-hydroxymethylfurfural (5-HMF), a promising substitute for fossil-derived compounds, by combining halogenated metal ionic liquids (ILs) and organic acids through one-pot hydrothermal reaction. Factors such as the type of ILs and organic acids, reaction time and temperature, as well as the quantity of dimethyl sulfoxide (DMSO) in the solvent, and the loading of substrate, IL, and organic acid were investigated for their impact on 5-HMF yield. Optimization of reaction conditions led to the attainment of the highest 5-HMF yield, reaching 33.1 ± 0.34 % based on the cellulose content within the passion fruit shell. Furthermore, the structural and morphological changes of the solid residues were analysed through techniques such as Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). These analyses revealed the progressive conversion of cellulose, hemicellulose, and lignin, accompanied by the formation of humin by-products. This integrated approach for 5-HMF production from agricultural waste introduced novel possibilities for transforming sustainable biomass resources into valuable chemical products.

Breath Biopsy Reveals Systemic Immunothrombosis and Its Resolution Through Bioorthogonal Dendritic Nanoprobes.

Immunothrombosis, an inflammation-dependent activation of the coagulation cascade, leads to microthrombi formations in small vessels. It is a dreaded complication of COVID-19 and a major cause of respiratory failure. Due to their size and disseminated nature, microthrombi are currently undetectable. Here, we introduce non-invasive detection of a volatile reporter in the exhaled air for assessment of systemic immunothrombosis. A dendritic nanoprobe, containing high loading of a thrombin-sensitive substrate, was selectively cleaved by thrombin, resulting in release of a synthetic bioorthogonal volatile organic compound (VOC). The VOC was quantitated in the exhaled air biopsies via gas chromatography mass spectrometry (GC-MS), allowing near realtime assessment of systemic immunothrombosis. The VOC detection can be further improved with more rapid and sensitive MS-based technologies. The amount of the VOC in the exhaled air decreased with resolution of the microvascular inflammation and intravascular fibrin depositions. Through conjugation of the thrombin-sensitive peptide with a rhodol derivative, a novel thrombin-sensitive fluorescent nanoprobe was developed for intravital visualization of thrombin activity in actively growing thrombi. These results establish unprecedented detection of thrombin activity in vivo, addressing an unmet medical need. Our novel approach facilitates diagnosis of immunothrombosis in diseases such as diabetic complications, disseminated intravascular coagulation, and COVID-19. This article is protected by copyright. All rights reserved.

Tailored Pre-Lithiation of Carbon Anodes Using Melt Deposited Thin Lithium

The user demands for Lithium ion batteries in mobile applications and electric vehicles request steady improvement in terms of capacity and cycle life. State-of-the-art lithium ion batteries irreversibly loose about 10 % of the capacity during the first cycles due to SEI formation. Therefore, 10 % of the cathode material is not used during the rest of the cells life which results in a waste of cathode material and leads to a lowered range of battery electric vehicles. Therefore, these losses must be compensated to ensure efficient resource utilization and to further increase the capacity of the lithium ion battery.We have developed a method to compensate these capacity losses by pre-lithiation: A fast and simple approach of electrolyte-free direct contact pre-lithiation leads to targeted degrees of pre-lithiation in a range of 7-50 % for state-of-the-art graphite electrodes. The parameters pressure (0-40 MPa), temperature (20-150°C) and time (0-60 min) are used to transfer lithium from a temporary substrate to the graphite anode. This process uses 1-5 µm thin lithium films made by the Fraunhofer IWS lithium melt deposition process as a lithium source.[1] The degree of pre-lithiation can be controlled by the lithium loading of the temporary substrate. NCM full cells built with pre-lithiated graphite electrodes where electrochemically evaluated in comparison to unlithiated electrodes. They show 6.5 % capacity increase after the first cycles using the additional lithium to form the SEI during the first cycles. The parameter influence of the pre-lithiation process on the initial coulomb efficiency of cells with pre-lithiated graphite electrodes is examined in half cells showing an ICE of 99.91 % for the best parameters.This method of electrolyte-free direct contact pre-lithiation shows an efficient way to further increase the capacity of state-of-the-art LIBs with graphite electrodes by increasing the cathode material utilization. It can potentially be scaled up to a roll-to-roll process using a heated calender nip. The temporary substrates with tailored lithium loading can be processed by lithium melt deposition in an efficient way with high lithium yield and high precision.[1] K. Schönherr, B. Schumm, F. Hippauf, R. Lissy, H. Althues, C. Leyens, S. Kaskel, Chemical Engineering Journal Advances 2022, 9, 100218. Figure 1

A reconfigurable ultra-broadband transparent absorber combined with ITO and structural water.

In this paper, a reconfigurable transparent metamaterial absorber consisting of a double-layer indium tin oxide (ITO) complementary resonant structure with a structural water-based substrate is proposed. The double-layer resonant pattern gives rise to two stable resonant peaks, and the loading of the water-based substrate can enhance the microwave absorption of the overall structure. By adjusting the thickness of the water layer in the substrate, the microwave absorption performance of the structure can be switched between dual-band and ultra-broadband, with more than 90% efficient microwave absorption covering the frequency range of 6.1 GHz-35.2 GHz. The absorption mechanism is revealed by analyzing the structure surface current as well as the equivalent dielectric constant. We also experimentally verified its microwave absorption and optical transparency properties. Due to its excellent tunable microwave absorption performance and high optical transparency, the proposed absorber has a large application value in stealth devices and optical windows.

Bioethanol from Napier grass employing different fermentation strategies to evaluate a suitable operation for batch bioethanol production

• Variations in substrate and enzyme additions in SSF of Napier grass were compared. • SHF and SSF resulted in 30.6 g/L and 28.5 g/L ethanol from 15% Napier grass. • Alleviate mixing problem by portioning addition did not improve ethanol production. • Pre-incubating the grass before SSF negatively impacts ethanol production. • Extra loading of substrate during SSF resulted in higher ethanol production. Napier grass has been used as animal feed especially in countries with tropical climates. As interest in alternative feedstocks for fuel bioethanol increases, Napier grass has been considered as a potential feedstock for lignocellulosic bioethanol production. Two main fermentation strategies, including separate hydrolysis and fermentation (SHF) and simultaneous saccharification and fermentation (SSF), were investigated with various substrate and enzyme feeding patterns in SSF. Total substrate loading of 15% and enzyme dosage of 40 FPU/g substrate were controlled to compare the performance of each fermentation variation. SHF and SSF resulted in similar ethanol production of 30.6 ± 0.4 g/L and 28.5 ± 2.3 g/L. Preincubation of grass and enzyme resulted in significant lower ethanol at 20.3 ± 1.6 g/L. Portioning the addition of grass and enzyme did not change the ethanol production significantly. Increasing the grass loading to 30% via portioning approach resulted in an increase in ethanol production in batch fermentation, while the addition of extra enzyme did not help with increasing ethanol production.

Structural insights into the substrate selectivity of α-oxoamine synthases from marine Vibrio sp. QWI-06

Pyridoxal phosphate (PLP)–dependent α-oxoamine synthases are generally believed to be responsible for offloading and elongating polyketides or catalyzing the condensation of amino acids and acyl-CoA thioester substrates, such as serine into sphingolipids and cysteate into sulfonolipids. Previously, we discovered vitroprocines, which are tyrosine- and phenylalanine-polyketide derivatives, as potential new antibiotics from the genus Vibrio. Using bioinformatics analysis, we identified putative genes of PLP-dependent enzyme from marine Vibrio sp. QWI-06, implying a capability to produce amino-polyketide derivatives. One of these genes was cloned, and the recombinant protein, termed Vibrio sp. QWI-06 α-oxoamine synthases-1 (VsAOS1), was overexpressed for structural and biochemical characterization. The crystal structure of the dimeric VsAOS1 was determined at 1.8-Å resolution in the presence of L-glycine. The electron density map indicated a glycine molecule occupying the pyridoxal binding site in one monomer, suggesting a snapshot of the initiation process upon the loading of amino acid substrate. In mass spectrometry analysis, VsAOS1 strictly acted to condense L-glycine with C12 or C16 acyl-CoA, including unsaturated acyl analog. Furthermore, a single residue replacement of VsAOS1 (G243S) allowed the enzyme to generate sphingoid derivative when L-serine and lauroyl-CoA were used as substrates. Our data elucidate the mechanism of substrate binding and selectivity by the VsAOS1 and provide a thorough understanding of the molecular basis for the amino acid preference of AOS members.

Crystal structure of the condensation domain from lovastatin polyketide synthase

The highly reducing iterative polyketide synthases responsible for lovastatin biosynthesis contains a section homologous to condensation (CON) domain observed in nonribosomal peptide synthetases (NRPSs). In the present study, we expressed the isolated lovastatin CON domain and solved the crystal structure to 1.79 Å resolution. The overall structure shows similarity to canonical condensation domains of NRPSs, containing the N-terminal and C-terminal subdomains that resemble enzymes of chloramphenicol acetyltransferase family, whereas distinct structural features are observed at the active site. The acceptor entry of the substrate channel is blocked by a flexible loop, thereby preventing the loading of substrate for a new round of chain elongation. The mutation of conserved catalytic motif located at the midpoint of substrate channel agrees with the incapability of CON to catalyzed amide-bond formation. The structure helps to understand the function of CON in lovastatin biosynthesis.

Computer-Aided Design and Simulation of a Membrane Bioreactor for Produced Water Treatment

Membrane Bio Reactor (MBR) has been designed and simulation for the treatment of Chemical Oxygen Demand (COD), Total Suspended Solids (TSS), Total Organic Carbon (TOC), Total Dissolved Solid (TDS) and Oil/ Grease in produced water at a capacity of 54.1778 kg/hr for removal of 95%-99% contaminants. The MBR design equations were developed using the law of conservation of mass to determine the dimensions and functional parameters. The developed performance equations were integrated numerically using fourth-order Runge-Kutta embedded in MATLAB computer program to determine the optimum range of values of the reactor functional dimensions and functional parameters. The effect of rate of energy supply per reactor volume and substrate specific rate constant on the capacity of the membrane bioreactor were investigated. Also, the effect of initial loading of substrate on Solid Retention Time (SRT) was also investigated. Results showed that kinetic parameters influenced the percentage removal of contaminants as Hydraulic Retention Time (HRT) and size of MBR decreased with increase in specific rate constant at fixed conversion of contaminants. Also, HRT and MBR size increased as the conversion of Chemical Oxygen Demand (COD) was increased, while increased in the ratio of energy supplied per volume resulted in decreased of MBR volume. The effect of initial loading of substrate on SRT showed that increased in substrate loading increased the retention time of the solid at fixed substrate conversion, while the conversion of substrate to microorganism increased as the solid retention time was increased. The increased in initial loading of substrate concentration increased the production of Mixed Liquor Suspended Solids (MLSS). Thus, the size of MBR required for the conversion of the investigated contaminants at the design percentage removal increased in the following order: oil/grease < TSS < TOC < TDS. The MBR volume, height and HRT were 1.10 and 5.29 m3; 0.98 and 4.68 m; and 1.38 and 6.62 at 95% and 99% respectively, while the SRT was 82.67 days.

Designing cellulosic and nanocellulosic sensors for interface with a protease sequestrant wound-dressing prototype: Implications of material selection for dressing and protease sensor design.

Interfacing nanocellulosic-based biosensors with chronic wound dressings for protease point of care diagnostics combines functional material properties of high specific surface area, appropriate surface charge, and hydrophilicity with biocompatibility to the wound environment. Combining a protease sensor with a dressing is consistent with the concept of an intelligent dressing, which has been a goal of wound-dressing design for more than a quarter century. We present here biosensors with a nanocellulosic transducer surface (nanocrystals, nanocellulose composites, and nanocellulosic aerogels) immobilized with a fluorescent elastase tripeptide or tetrapeptide biomolecule, which has selectivity and affinity for human neutrophil elastase present in chronic wound fluid. The specific surface area of the materials correlates with a greater loading of the elastase peptide substrate. Nitrogen adsorption and mercury intrusion studies revealed gas permeable systems with different porosities (28-98%) and pore sizes (2-50 nm, 210 µm) respectively, which influence water vapor transmission rates. A correlation between zeta potential values and the degree of protease sequestration imply that the greater the negative surface charge of the nanomaterials, the greater the sequestration of positively charged neutrophil proteases. The biosensors gave detection sensitivities of 0.015-0.13 units/ml, which are at detectable human neutrophil elastase levels present in chronic wound fluid. Thus, the physical and interactive biochemical properties of the nano-based biosensors are suitable for interfacing with protease sequestrant prototype wound dressings. A discussion of the relevance of protease sensors and cellulose nanomaterials to current chronic wound dressing design and technology is included.

First Tandem‐Type One‐Pot Process Combining Asymmetric Organo‐ and Biocatalytic Reactions in Aqueous Media Exemplified for the Enantioselective and Diastereoselective Synthesis of 1,3‐Diols

A suitable “process window” was identified for the combination of an asymmetric organocatalytic aldol reaction and subsequent biocatalytic reduction in aqueous medium, which thus enabled the enantio‐ and diastereoselective synthesis of 1,3‐diols in a tandem‐type, one‐pot process. A key feature of this one‐pot synthesis is the high 500 mm loading of the aldehyde substrate used as a starting material.

Broadband compact microstrip patch antenna design loaded by multiple split ring resonator superstrate and substrate

We present microstrip patch antenna loaded with multiple split ring resonator substrate and superstrate. We analyze how the loading of split ring resonator superstrate and substrate can improve the bandwidth compared to the simple microstrip patch antenna and microstrip patch antenna loaded with split ring resonator superstrate. Another important observation is made for multiple split ring resonator loading in superstrate and substrate of microstrip patch antenna. The design is compared for two, three, and four-ring split ring resonator loading. The designs are also compared for different gap spacing between the rings. All three designs are compared for small gap and large gap between the rings. The design results in the form of reflection coefficient and bandwidth is presented in this manuscript. The design results are also compared with previously published designs.

Improvement in Enzymatic Hydrolysis of Waste Office Paper with Chemical Pretreatment and Enzyme Loading Reduced

This work evaluates the effects of increasing hydrolysis time, enzyme loading and mass of substrate on the formation of glucose in the enzymatic hydrolysis of waste office paper, after chemical or physical pre-treatment. Initially, for this study, a factorial design 24 was applied. The type of pretreatment was the only significant effect on the glucose release. Maximum glucose concentration was less than 0.5 g/L, when physical pre-treatment was used. Physical pre-treatment was therefore discarded. A new factorial design with three factors and higher number of level of treatments (hydrolysis time—24, 48 and 72 h; enzyme loading—5.2, 7.8 and 10.4 FPU/g substrate; mass of waste office paper—2.25, 3.00 and 3.75 g) was applied, after chemical pre-treatment. The increase in mass of paper increased the glucose concentration. On the other hand, the increase time of hydrolysis or enzyme loading did not influence glucose release. Maximum glucose concentration (23 g/L) was about 50 times higher than that obtained when physical pretreatment was used, reducing by half the enzyme load. Optimum conditions of enzymatic hydrolysis was obtained at 24 h of hydrolysis, using lower enzyme loading (5.2 FPU/g) and higher mass of waste office paper (3.75 g; 7.5 % w/V), after chemical pre-treatment.

Influence of mobile shale on thrust faults: Insights from discrete element simulations

We study the effects of sedimentary loading of a mobile shale substrate, using two-dimensional discrete element modeling. We develop an updip extensional zone connected at depth to a downdip contractional zone, allowing us to study the formation of gravity-driven fold and thrust belts, and the evolution of decollements within this system. We compare our models to the Niger Delta type locale for shale tectonics. In general, most seismic interpretations of the Niger Delta include decollement(s) at the top of the mobile shale unit, but exact locations vary depending on area of investigation. Our models, particularly ones with mobile shale thicker than 2 km (1.2 mi), show more diffuse decollements, spanning the width of the mobile shale unit, which propagate out in front of the syntectonic sediment wedge and connect normal faults in the extensional zone with toe thrusts in the contractional zone. We also look at the distributions of stress and strain within our models, plotting the distributions of (maximum principal stress) and relating that to the vergence of thrust faults developed in our models. We quantify the amount of strain in different sections of the models, showing that extension is much greater than compression in the fold and thrust belt(s) alone, and that compression is distributed throughout the model, including in front of the fold and thrust belt.

Simultaneous Saccharification and Fermentation (SSF) of Cellulose from Lignocellulise for 2&lt;sup&gt;nd&lt;/sup&gt; Bioethanol Production: A Review

Lignocellulosic materials, a abundant and renewable resources in the world, can be utilized for 2nd bioethanol production. Simultaneous saccharification and fermentation (SSF) has been regarded as a promising process for bioethanol production. This article reviews the status of SSF process for bioethanol production and its challenges for reducing production cost and increasing process efficiency, and the key issues mainly including high loading of cellulose substrate, high temperature of SSF reaction and its corresponding thermo-tolerant microorganism as well as alleviation or elimination of inhibitors have been analyzed. At last future prospects for commercialization of the 2nd bioethanol production by lignocellulosic materials with low capital investment are stated.

Thermal laser micro-adjustment using picosecond pulse durations

Thermal laser micro forming (LμF) is a non-contact process for the precise adjustment of micro-scale metallic components. Micro-electronic systems often comprise functional components which require highly accurate micro-scale adjustment after fabrication. Such functional components are typically difficult to access and highly sensitive to mechanical force. The application of lasers offers the potential for controlled and repeatable micro-adjustment of these components in a contact free process.The use of a picosecond pulsed laser source reduces the heat diffusion depth when compared to longer pulse durations, resulting in less thermal loading of the bulk substrate. When combined with high repetition rates, localized heat accumulation in micro-scale components can be achieved and utilized in a thermal forming process.In this work, the micro-adjustment of 1000μm×300μm stainless steel actuator arms using a mode locked fibre laser with a maximum pulse energy and duration of 3μJ and 20ps respectively was conducted. The effect of pulse overlap, laser power, irradiation strategy and number of irradiations on the net bend angle is presented.

Modelo Matemático para Estimación de Eficiencias Fotónicas No-Intrínsecas en Reacciones Fotocatalíticas Heterogéneas

A semi-empirical model was formulated to estimate the photonic efficiency of photocatalytic reactions in heterogeneous systems. This is a function of a pre-exponential factor called intrinsic photonic-efficiency and an exponential factor that quantified the effect of catalyst loading, geometry, and initial concentration of substrate. The assumptions and the model were validated on the photodegradation of dichloroacetic acid in three lab-scale heterogeneous photocatalytic reactors, using TiO2-P25 and low energy monochromatic radiation. It was found that the model is highly predictive for photonic efficiencies with relative errors below 1.8%.

Loading effects of self-biased magnetic films on patch antennas with substrate/superstrate sandwich structure

From materials perspective, it has been challenging to achieve relative permeability mr . 1i n self- biased antenna substrates at gigahertz frequencies. In this study, self-biased microwave NiCo ferrite films were deposited with a low-temperature spin spray deposition process. Novel antenna designs with self-biased NiCo- ferrite films were investigated at 2.1 GHz. These magnetic antennas with several micrometers thick ferrite films show an enhanced antenna performance over the unloaded patch antenna. With ferrite loading of the alumina substrate, the resonant frequency shows a down shift of 30 - 50 MHz. The radiation efficiency is increased from 41% for the non-magnetic antenna to 76% for the ferrite films loaded antenna, together with an antenna gain enhancement greater than 1 dB over the non-magnetic antenna. The combination of these self-biased ferrite films and alumina substrates can lead to miniature antennas with enhanced performance at gigahertz frequencies.

Tunable Miniaturized Patch Antennas With Self-Biased Multilayer Magnetic Films

<para xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> Magneto-dielectric substrates with thin magnetic films show great potential in realizing electrically small tunable antennas with enhanced bandwidth, improved directivity, and high efficiency. This communication introduces self-biased NiCo-ferrite magnetic films as a practical mean to tune a patch antenna by loading single layer and multilayer self-biased ferrite films. The central resonant frequency of the unloaded patch antenna is measured at 2.1 GHz with a bandwidth of 18 MHz. However, with ferrite loading of the alumina substrate, this frequency is shown to be tunable within a range of 12 MHz–40 MHz, and the antenna efficiency is increased from 41% of the non-magnetic antenna to 56%, 65%, and 74% for the three magnetic antennas. The omnidirectional radiation pattern is significantly enhanced with the <formula formulatype="inline"> <tex Notation="TeX">${-}5$</tex></formula> dBic gain beamwidth increased from 140<formula formulatype="inline"><tex Notation="TeX">$^{\circ}$</tex></formula> to 155<formula formulatype="inline"><tex Notation="TeX">$^{\circ}$</tex></formula>, 156<formula formulatype="inline"><tex Notation="TeX">$^{\circ}$</tex></formula> and 160<formula formulatype="inline"><tex Notation="TeX">$^{\circ}$</tex></formula>, respectively for the three ferrite loaded antennas. In addition, the gains of the three magnetic antennas are enhanced by 0.32, 0.77, and 1.1 dB, respectively, over the unloaded antenna. </para>

Synthesis of para‐Amino Benzoic Acid–TiO2 Hybrid Nanostructures of Controlled Functionality by an Aqueous One‐Step Process

AbstractIn situ amino acid surface‐modified TiO2 nanoparticle syntheses were performed by a simple one‐pot hydrolysis of heteroleptic titanium alkoxide [Ti(OiPr)3(O2CC6H4NH2)]m in water with NnBu4Br. This process allowed precise control of the surface grafting rate by varying the amount of precursors and provided highly functionalized nanomaterials. Their compositions and microstructures were determined by C, H and N elemental analyses, TGA‐MS, 13C CP‐MAS NMR, XRD, TEM, BET, Raleigh diffusion, FTIR, Raman, XPS and UV/Vis experiments. The results indicated that (i) the aggregation rate increased with an increase in the loading of the organic substrate and (ii) the amino acid is chemisorbed as a carboxylate group onto the TiO2 nanoparticles, which leads to a strong interaction between the amino acid and the TiO2 nanoparticle and good stability of these hybrids. Applications of low‐aggregated nanomaterials were demonstrated as efficient protection additive against UVA + UVB radiations.(© Wiley‐VCH Verlag GmbH &amp; Co. KGaA, 69451 Weinheim, Germany, 2008)

Effects of Substrate Loading on Enzymatic Hydrolysis and Viscosity of Pretreated Barley Straw

In this study, the applicability of a "fed-batch" strategy, that is, sequential loading of substrate or substrate plus enzymes during enzymatic hydrolysis was evaluated for hydrolysis of steam-pretreated barley straw. The specific aims were to achieve hydrolysis of high substrate levels, low viscosity during hydrolysis, and high glucose concentrations. An enzyme system comprising Celluclast and Novozyme 188, a commercial cellulase product derived from Trichoderma reesei and a beta-glucosidase derived from Aspergillus niger, respectively, was used for the enzymatic hydrolysis. The highest final glucose concentration, 78 g/l, after 72 h of reaction, was obtained with an initial, full substrate loading of 15% dry matter weight/weight (w/w DM). Conversely, the glucose yields, in grams per gram of DM, were highest at lower substrate concentrations, with the highest glucose yield being 0.53 g/g DM for the reaction with a substrate loading of 5% w/w DM after 72 h. The reactions subjected to gradual loading of substrate or substrate plus enzymes to increase the substrate levels from 5 to 15% w/w DM, consistently provided lower concentrations of glucose after 72 h of reaction; however, the initial rates of conversion varied in the different reactions. Rapid cellulose degradation was accompanied by rapid decreases in viscosity before addition of extra substrate, but when extra substrate or substrate plus enzymes were added, the viscosities of the slurries increased and the hydrolytic efficiencies decreased temporarily.