Direct Product Research Articles

Application of neural network in prediction of acetic acid yield by Acetobacters

In the present work, artificial neural network (ANN) is applied for the estimation of acetic acid yield for 3 different species of Acetobacters like, Acetobacter pasteurianus (NCIM 2104), Acetobacter aceti (NCIM 2116) and Acetobacter xylinum (NCIM 2526). Though there is open literature mentioning acetic acid and ANN can be found, they hardly describe the usage of ANN in prediction of fermentation based acetic acid production. Indeed, a deep dearth of existing literature is felt in this area to develop a robust ANN model to predict the yield of biologically obtained acetic acid and this work is a step towards bridging that research gap. The performance of the model has been estimated with R2 (0.992, 0.988 and 0.992, respectively for the mentioned microbial species) and RMSE (0.0287, 0.034 and 0.020, respectively for the same species). The most relevant operating parameters like, temperature, agitator speed, concentrations of supplemented yeast extract and tryptone, have been considered to carry out fermentation on cheese whey permeate containing fermentable lactose (48.5 g L-1) to transform into acetic acid. Outcome datasets obtained from rigorous experimental investigations performed on the direct fermentative production of acetic acid are trained in the ANN model to predict the product yield. Such machine-learning methodology encourages reasonably accurate prediction of product generation which is extremely tough to obtain through classical analytical processes.

Direct CO2 mineralization and evolution behavior of fine CaCO3 from ammonia-induced phosphogypsum mineral carbonation

The mineral carbonation of phosphogypsum (PG) presents considerable potential for simultaneous CO2 sequestration and high-value utilization of PG. Variations in carbon footprints are crucial for enhancing carbonation efficiency and regulating product formation. This study explores the mechanism of direct CO2 mineralization by PG and the evolution of the resulting product. The results demonstrate that 97.14% of the CaSO4·2H2O in PG can be converted to calcite under conditions including a nitrogen–sulfur molar ratio of 3, a liquid–solid ratio of 6, a CO2 flowrate of 0.4 L/min, and a stirring rate of 800 rpm for 60 min. The carbonation rate exhibits significant variation with time, occurring in three distinct stages. Initially, CO2 reacts with ammonia to form (NH4)2CO3, releasing greater heat. This heat inhibits the dissolution of Ca2+ from PG, resulting in a lower carbonation efficiency, as only a limited amount of Ca2+ reacts with CO32– to preferentially form amorphous CaCO3 (ACC). As CO32– formation reaches equilibrium, the endothermic properties of the reaction between CaSO4 and (NH4)2CO3 promote the dissolution of Ca2+ from PG, further accelerating CO2 mineralization and resulting in significant increases in carbonation efficiency and ACC production. The ACC is rapidly transformed into calcite via a “dissolution-reprecipitation” mechanism. However, the carbonation rate of PG decreases as saturation is approached, mainly resulting from the aggregation of fine CaCO3 particles on the PG surface. As a result, the direct CO2 sequestration process by PG follows a carbon footprint sequence of “CO2–(NH4)2CO3–ACC–calcite”. This study provides significant insights into the mechanisms of direct CO2 mineralization and product evolution and offers a basis for optimizing carbonation processes enhancement and regulating product phases.

Bipolar Membrane Capacitive Deionization for the Selective Capture of Lithium Ions from Brines and Conversion to Lithium Hydroxide

Meeting the increasing demand for lithium in vehicle electrification and renewable energy storage requires innovations in lithium-ion (Li+) separations. Traditional solar evaporation methods for lithium recovery are slow and consume tremendous volumes of water and secondary chemicals (acids and bases). This study introduces a bipolar membrane capacitive deionization (BPM-CDI) unit for direct lithium extraction and LiOH production without the external addition of acids and bases. Utilizing de-lithiated lithium-iron-phosphate (LFP) coated carbon cloth electrodes, the BPM-CDI unit demonstrates selective Li+ capture over competing ions. Molecular dynamics simulations and H-cell experiments elucidate pH inversion mechanisms during Li+ release, yielding LiOH. The BPM-CDI platform efficiently removes Li+ from synthetic brines featuring 8x higher Mg2+ concentrations (200 ppm Mg2+) and 26x higher Na+ concentrations (682 ppm Na+), achieving a LiOH concentration of 124 ppm (36 ppm Li+) after 8 cycles of recirculation. Post-mortem analysis confirms electrode integrity and stability. BPM-CDI integrated with selective electrodes is a promising electrochemical separation-reactor platform for lithium recovery while producing LiOH.

On the twisted group ring isomorphism problem for a class of groups

The twisted group ring isomorphism problem (TGRIP) is a variation of the classical group ring isomorphism problem. It asks whether the ring structure of the twisted group ring determines the group up to isomorphism. In this article, we study the TGRIP for direct product and central product of groups. We provide some criteria to answer the TGRIP for groups by answering the TGRIP for certain associated quotients. As an application of these results, we provide several examples. Finally, we answer the TGRIP for extra-special p-groups, and for all but five groups of order p5, where p≥5 is prime.

P-Permutation equivalences between blocks of group algebras

We extend the notion of a p-permutation equivalence between two p-blocks A and B of finite groups G and H, from the definition in [5] to a virtual p-permutation bimodule whose components have twisted diagonal vertices. It is shown that various invariants of A and B are preserved, including defect groups, fusion systems, and Külshammer-Puig classes. Moreover it is shown that p-permutation equivalences have additional surprising properties. They have only one constituent with maximal vertex and the set of p-permutation equivalences between A and B is finite (possibly empty). The paper uses new methods: a consequent use of module structures on subgroups of G×H arising from Brauer constructions which in general are not direct product subgroups, the necessary adaptation of the notion of tensor products between bimodules, and a general formula (stated in these new terms) for the Brauer construction of a tensor product of p-permutation bimodules.

Production of 5-hydroxymethylfurfural and 2,5-dimethylfuran from fructose using wine lees-derived C-SO3H and Pt5Fe5/C catalyst

Direct production of 2,5-dimethylfuran (DMF) from fructose is crucial for developing biomass-derived fuels, yet it presents significant challenges due to the need for multifunctional active sites for dehydration and hydrodeoxygenation. Meanwhile, the disposal of wine lees, a major winemaking by-product, incurs substantial costs. Herein, a hybrid catalyst system of sulfonated wine lees carbon (WLC-SO3H) and PtFe/C was introduced, achieving a DMF yield of 66.4 % directly from fructose. WLC-SO3H, with enhanced Brønsted acidity, demonstrated high activity in dehydrating fructose to 5-hydroxymethylfurfural (HMF) with a 98.2 % yield. PtFe/C effectively catalyzed the hydrodeoxygenation of HMF to DMF, driven by the strong interaction between Pt and Fe species. This interaction was confirmed through in situ DRIFTS and theoretical calculations, highlighting the system's superior catalytic performance.

Pro-[formula omitted] RAAGs

Let C be a class of finite groups closed under taking subgroups, quotients, and extensions with abelian kernel. The right-angled Artin pro-C group GΓ (pro-C RAAG for short) is the pro-C completion of the right-angled Artin group G(Γ) associated with the finite simplicial graph Γ.In the first part, we describe structural properties of pro-C RAAGs. Among others, we describe the centraliser of an element and show that pro-C RAAGs satisfy the Tits' alternative, that standard subgroups are isolated, and that 2-generated pro-p subgroups of pro-C RAAGs are either free pro-p or free abelian pro-p.In the second part, we characterise splittings of pro-C RAAGs in terms of the defining graph. More precisely, we prove that a pro-C RAAG GΓ splits as a non-trivial direct product if and only if Γ is a join and it splits over an abelian pro-C group if and only if a connected component of Γ is a complete graph or it has a complete disconnecting subgraph. We then use this characterisation to describe an abelian JSJ decomposition of a pro-C RAAG, in the sense of Guirardel and Levitt [GL17].

Pseudo Rho-Algebras in Fields with their Applications Using Polynomials with Two Variables

The main purpose of this work is to present the concept of pseudo Rho-algebra as a generalization of the Rho-algebra. We investigate this type behaves nicely in terms of common mappings like homomorphisms and direct products. In fact, we can show identify kernel objects and the fundamental theorem of homomorphisms using Rho-ideals in this theory. Also, some important classes of pseudo Rho-algebra and their applications are investigated and studied. Moreover, the necessary characteristics for or tantamount to membership in major subtypes of pseudo Rho/d-algebras under these cases are identified. The Rho/d-algebras and pseudo Rho/d-algebras are generated using some new classes of polynomials with two variables that are introduced in this work, like commutative identical, associative identical, regular identical, proper conditionally identical, and improper conditionally identical. Finally, the category of pseudo Rho/d-algebras can be classified using a conditionally couple, giving us additional flexibility in dealing with two different fields.

Molecular Engineering of Poly(Ionic Liquid) for Direct and Continuous Production of Pure Formic Acid from Flue Gas.

Electrochemical CO2 reduction reaction (CO2RR) offers a promising approach to close the carbon cycle and reduce reliance on fossil fuels. However, traditional decoupled CO2RR processes involve energy-intensive CO2 capture, conversion, and product separation, which increases operational costs. Here, we report the development of a bismuth-poly(ionic liquid) (Bi-PIL) hybrid catalyst that exhibits exceptional electrocatalytic performance for CO2 conversion to formate. The Bi-PIL catalyst achieves over 90% Faradaic efficiency for formate over a wide potential range, even at low 15% v/v CO2 concentrations typical of industrial flue gas. The biphenyl in PIL backbone affords hydrophobicity while maintaining high ionic conductivity, effectively mitigating the flooding issues. The PIL layer plays a crucial role as a CO2 concentrator and co-catalyst that accelerates the CO2RR kinetics. Furthermore, we demonstrate the potential of Bi-PIL catalysts in a solid-state electrolyte (SSE) electrolyzer for the continuous and direct production of pure formic acid solutions from flue gas. Techno-economic analysis suggests that this integrated process can produce formic acid at a significantly reduced cost compared to the traditional decoupled approaches. This work presents a promising strategy to overcome the challenges associated with low-concentration CO2 utilization and streamline the production of valuable liquid fuels and chemicals from CO2.

Metric Dimension of Corona Product and Join Graph of Zero Divisor Graphs of Direct Product of Finite Fields

The metric dimension of a graph is the smallest number of vertices such that all vertices are uniquely determined by their distances to the chosen vertices. The corona product of graphs G and H is the graph G ⊙ H obtained by taking one copy of G , called the center graph, | V ( G ) | copies of H , called the outer graph, and making the j t h vertex of G adjacent to every vertex of the j t h copy of H , where 1 ⩽ j ⩽ | V ( G ) | . The Join graph G + H of two graphs G and H is the graph with vertex set V ( G + H ) = V ( G ) ∪ V ( H ) and edge set E ( G + H ) = E ( G ) ∪ E ( H ) ∪ { u v : u ∈ V ( G ) , v ∈ V ( H ) } . In this paper, we determine the Metric dimension of Corona product and Join graph of zero divisor graphs of direct product of finite fields.

Additive Optimization Method for Choosing CNC Machines for Technological Preparation of Machine-Building Production

The introduction of Industry 4.0 into the technological preparation of production leads to the optimization of processes, including the processes of selecting equipment and tools, reducing cycle time, and reducing costs. Technological preparation of production involves a set of works that make it possible to start manufacturing a new product in a given volume. Features of technological preparation of production when using CNC machines follow from the fact that a significant part of the work from the sphere of direct production is transferred to the area of its technological preparation. Technological preparation of production plays an important role in the successful functioning of a machine-building enterprise. Optimization of equipment selection allows you to increase productivity, reduce costs and improve product quality. The use of modern optimization methods and information technology allows you to make this process more efficient and accurate. The article provides a methodology for calculating the additive criterion for optimizing the selection of the best option for CNC machines.

Hyperplanes of Segre Geometries

We classify the geometric hyperplanes of the Segre geometries, that is, direct products of two projective spaces. In order to do so, we use the concept of a generalised duality. We apply the classification to Segre varieties and determine precisely which geometric hyperplanes are induced by hyperplanes of the ambient projective space. As a consequence we find that all geometric hyperplanes are induced by hyperplanes of the ambient projective space if, and only if, the underlying field has order 2 or 3 .

The state of food safety and hygiene in bottled water production facilities in the five provinces of the Central Highlands region in 2023

A cross-sectional descriptive study was conducted from March 2023 to December 2023 to assess the implementation of food safety regulations in bottled water production facilities across the five provinces of the Central Highlands region (Kon Tum, Gia Lai, Dak Lak, Dak Nong, Lam Dong) in 2023. The study evaluated food safety conditions, practices of direct production personnel, and collected bottled water samples for testing five bacterial indicators according to QCVN 6-1:2010/BYT. The results showed that the majority of facilities did not meet the criteria of physical infrastructure conditions at 74.7% (56/75), equipment and utensil conditions at 74.7% (56/75), conditions of direct production personnel at 44.0% (33/75), personal hygiene practices at 65.3% (49/75), and bottle cleaning practices at 72% (54/75). The rate of microbial contamination in bottled water products was 70.7% (53/75), of which the main contamination was Pseudomonas aeruginosa 45.3% (34/75), total Coliforms 42.7% (32/75), Clostridia 6.7% (5/75) and Streptococci feacal 2.0% (2/75). Some factors related to bacterial contamination in bottled water products are the condition of facilities, practicing personal hygiene, and practicing bottle hygiene.

Industrial SMB chromatography as an alternative to the conventional refining of raw cane sugar

Simulated moving bed (SMB) chromatography is a well-established and widespread unit operation in the beet sugar industry and has been practiced commercially for more than thirty years. SMB chromatography has proven to be very efficient at removing inorganic ash components and colorants from sugar liquors, particularly those colorants with relatively high molecular masses. Recent optimization of the separation using raw sugar with a color ranging from 2000 IU up to 4000 IU has focused on minimizing the capital and operating costs of a chromatography system to replace the various purification and decolorization steps in conventional raw cane sugar refining. Decolorization levels exceeding 89% have been reliably achieved in the extract fraction from chromatography, along with ash removals ranging from 92% to 97%. As only water is added to purify the sugar, the application of this technology, in combination with modern industrial heat pumps and mechanical vapor recompression, allows for a powerful CO2-neutral process, with all the associated benefits regarding permits and marketability. The potential of this technology includes integration into new refinery projects (either standalone or back-end) by replacing affination, carbonatation and ion exchange decolorization (with raw sugar colors of up to 5000 IU), to expansion of existing refinery sites for slip stream processing of raw sugar syrups or refinery run-off syrups after clarification, and to the introduction of new process steps, such as direct liquid sugar production from cane raw sugar.

Combinatorial Properties, Invariants and Structures Associated with the Direct Product of Alternating and Cyclic Groups Acting on the Cartesian Product of Two Sets

In relation to group action, much research has focused on the properties of individual permutation groups acting on both ordered and unordered subsets of a set, particularly within the Alternating group and Cyclic group. However, the action of the direct product of Alternating group and Cyclic group on the Cartesian product of two sets remains largely unexplored, suggesting that some properties of this group action are still undiscovered. This research paper therefore, aims to determine the combinatorial properties - specifically transitivity and primitivity - as well as invariants which includes ranks and subdegrees of this group action. Lemmas, theorems and definitions were utilized to achieve the objectives of study with significant use of the Orbit-Stabilizer theorem and Cauchy-Frobeneus lemma. Therefore in this paper, the results shows that for any value of <i>n</i> ≥ 3, the group action is transitive and imprimitive. Additionally, we found out that when <i>n</i> = 3, the rank is 9 and the corresponding subdegrees are ones repeated nine times that is, 1, 1, 1, 1, 1, 1, 1, 1, 1. Also, for any value of <i>n</i> > 4, the rank is 2n with corresponding subdegrees comprising of n suborbits of size 1 and n suborbits of size (<i>n</i> − 1).

Circulation of self-supplied water for significant energy recovery through heat integration

This study introduces an overhead heat-integrated distillation column (OHIDiC), a novel approach that maximizes heat recovery by multiple heat exchanges and product circulation. By utilizing the overhead vapor as a direct heat source, low-temperature feed and product water were used as cooling agents, thereby significantly reducing the condenser duty and reliance on cooling utilities. Additionally, the heated feed transfers heat to the column, leading to a substantial reduction of reboiler heat duty. Some of the heated product water is recycled back to the decanter for product cycling, while the rest is released as the final product. This circulation process ensures a continuous coolant supply, which contributes the reduction of condenser duty. Two processes were considered in this study, utilizing the water product from a non-reactive, and from a reactive separation within the system. When applied to the separation of a water-dodecanol mixture, OHIDiC reduced the condenser duty by 69.21% compared to a traditional distillation column, with a 31.46% reduction in the total utility consumption. When reactive distillation was incorporated into the OHIDiC, the higher overhead vapor temperature facilitated high heat transfer in the multiple heat exchange sections, thereby significantly reducing the total thermal load. This resulted in a reduction of up to 46.96% in total heat duty and a 36.06% decrease in CO2 emissions. These findings confirm that the OHIDiC achieves significant energy savings through the utilization of process-derived substances, with pronounced benefits when the temperature of the overhead vapor becomes higher.

Co-complexes on modified graphite surface for steady green hydrogen production from water at neutral pH.

Green hydrogen production from water is one attractive route to non-fossil fuel and a potential source of clean energy. Hydrogen is not only a zero-carbon energy source but can also be utilized as an efficient storage of electrical energy generated through various other sources, such as wind and solar. Cost-effective and environmentally benign direct hydrogen production through neutral water (∼pH 7) reduction is particularly challenging due to the low concentration of protons. There is currently a major need for easy-to-prepare, robust, as well as active electrode materials. Herein we report three new molecular electrodes that were prepared by anchoring commercially available, and environmentally benign cobalt-containing electrocatalysts with three different ligand frameworks (porphyrin, phthalocyanine, and corrin) on a structurally modified graphite foil surface. Under the studied reaction conditions (over 7h at 22°C), the electrode with Co-porphyrin is the most efficient for the water reduction with starting ∼740mV onset potential (OP) (vs. RHE, current density 2.5mA/cm2) and a Tafel slope (TS) of 103mV/dec. It is followed by the molecular electrodes having Co-phthalocyanine [825mV (OP), 138mV/dec (TS)] and Vitamin-B12 (Co-corrin moiety) [830mV (OP), 194 mv/dec (TS)]. A clear time-dependent improvement (>200mV over 3h) in the H2 production overpotential with the Co-porphyrin-containing cathode was observed. This is attributed to the activation due to water coordination to the Co-center. A long-term chronopotentiometric stability test shows a steady production of hydrogen from all three cathode surfaces throughout seven hours, confirmed using an H2 needle sensor. At a current density of 10mA/cm2, the Co-porphyrin-containing electrode showed a TOF value of 0.45s-1 at 870mV vs. RHE, whereas the Co-phthalocyanine and Vitamin-B12-containing electrodes showed 0.37 and 0.4s-1 at 1.22V and 1.15V (vs. RHE), respectively.

Structure of the Kuranishi spaces of pairs of Kähler manifolds and polystable Higgs bundles

AbstractLet be a compact Kähler manifold and be a Higgs bundle over it. We study the structure of the Kuranishi space for the pair when the Higgs bundle admits a harmonic metric or equivalently when the Higgs bundle is polystable and the Chern classes are 0. Under such assumptions, we show that the Kuranishi space of the pair is isomorphic to the direct product of the Kuranishi space of and the Kuranishi space of . Moreover, when is a Riemann surface and is stable and the degree is 0, we show that the deformation of the pair is unobstructed and calculate the dimension of the Kuranishi space.

Direct Formic Acid Production by CO2 Hydrogenation with Ir Complexes in HFIP under Supercritical Conditions

Direct Formic Acid Production by CO₂ Hydrogenation with Ir Complexes in HFIP under Supercritical Conditions

Stone Pseudovarieties

We extend the theory of profinite algebras, as it is used in the algebraic theory of regular languages, to the more general setting of Stone topological algebras with the ultimate goal of going beyond classes of regular languages. We introduce Stone pseudovarieties, that is, classes of Stone topological algebras of a fixed topological signature that are closed under taking Stone quotients, closed subalgebras and finite direct products. Looking at the dual Stone spaces of Boolean algebras of subsets of a given topological algebra, we find a simple characterization of when the dual space admits a natural structure of topological algebra; the characterization is given in terms of how the Boolean algebra behaves under the inverses of the operation evaluation mappings of each arity. This provides an alternative, which is presented in the form of an equivalence of categories, to the duality theory of M. Gehrke. As an application, a Stone quotient of a Stone topological algebra that is residually in a given Stone pseudovariety is shown to be also residually in it, thereby extending the corresponding result of M. Gehrke for the Stone pseudovariety of all finite algebras over discrete signatures, which was recently extended to topological signatures jointly by the authors and H. Goulet-Ouellet. The residual closure of a Stone pseudovariety is thus a Stone pseudovariety, and these are precisely the Stone analogues of varieties. A Birkhoff type theorem for Stone varieties is also established and it is shown how Reiterman’s theorem can be derived from it.