Loss Of Capacity Research Articles

Biological small molecule interface-modification fostering resilient interfacial chemistry for silicon-based anodes

Silicon-based materials, particularly at the microscale, are prone to rapid capacity fade due to substantial volume fluctuations during the charge-discharge cycles, significantly impeding their commercial viability. Constructing a stable solid electrolyte interface (SEI) is an effective means to improve the performances of silicon-based anodes. Here small biomolecules, tryptophan (Trp) and phytic acid (PA), are introduced as interface modifiers to optimize the interfacial chemistry of micron-silicon anodes. By engaging in the SEI formation process, these small biomolecules effectively regulate the chemical composition and mechanical properties of the formed SEI, fostering a more cohesive and durable interface. The simultaneous addition of PA and Trp has been observed to yield a synergistic effect, creating a tightly bonded and resilient SEI that confers markedly improved battery performances upon the co-modified micron silicon anodes. Density functional theory calculations reveal charge interactions between these small biomolecules and silicon particles, facilitating effective adsorption onto the silicon surface. Simultaneous adsorption of Trp and PA on silicon surface can significantly enhance adsorption strength, providing a compelling explanation for the observed synergistic effect of Trp and PA co-modification.

Carbon-decorated hydrated V10O24 nanorods for high-performance lithium-ion battery cathodes

This study reports the successful synthesis of carbon-decorated hydrated V10O24 (HVO@C) nanorods using a facile hydrothermal method. The synthesized material was comprehensively characterized using XRD, FTIR, Raman, TGA/DSC, BET, SEM, and HRTEM to reveal its structure and morphology, and the resulting electrode's electrochemical performance as a lithium-ion battery (LIB) cathode was evaluated for the first time. The HVO@C nanorods exhibited a remarkable initial capacity of 292.5 mAh g−1 at 75 mA g−1 current rate, exceeding most of the reported V2O5-based LIB cathodes. Notably, the HVO@C electrode retained a good capacity retention of 67.1 % and a slower capacity loss rate of 0.26 % after 125 cycles compared to most V2O5-based counterparts with shorter lifespans. This outstanding performance could be due to a synergistic interplay of structural characteristics. The large interlayer spacing within the nanorods facilitated unimpeded Li-ion diffusion, while the short diffusion path minimized transport limitations. Furthermore, the strategic incorporation of carbon coating enhanced electrical conductivity and structural stability, leading to enduring LIB battery performance. These results indicate that in-situ carbon-decorated hydrated V10O24 nanoparticles have great potential as a promising cathode electrode for LIBs with exceptional performance.

In-situ TiO2/reduced graphene oxide double-coated LiNi0.5Co0.2Mn0.3O2 microspheres as high-performance Li-ion cathode materials

LiNi0.5Co0.2Mn0.3O2(NCM) layered materials have high energy density and large power density but also exhibit obvious capacity fading and voltage decay during the cycle. A rational surface modification design is reported in this work to address these problems. Herein, tetrabutyl titanate (TBOT) was decomposed into TiO2 by hydrolysis-condensation reaction and high-temperature calcination, thus a homogeneous coating was generated on the surface of NCM. The coating layer of TiO2 stabilizes the crystal structure. Furthermore, rGO and reduced metal (Ni, Co, Ti) would be wrapped on the surface as a highly conductive second coating, which could provide a rapid electron conduction pathway. The dual surface-modified cathode shows an outstanding discharge capacity of 163.4 mAh g−1 at 0.2 C and 120 mAh g−1 at 10 C. This dual coating strategy provides valuable insights for further study on the modification mechanisms of other layered cathode materials.

In Situ Construction of Crumpled Ti3C2Tx Nanosheets Confined S-Doping Red Phosphorus by Ti-O-P Bonds for LIBs Anode with Enhanced Electrochemical Performance.

Red phosphorus (RP) with a high theoretical specific capacity (2596 mA h g-1) and a moderate lithiation potential (∼0.7 V vs Li+/Li) holds promise as an anode material for lithium-ion batteries (LIBs), which still confronts discernible challenges, including low electrical conductivity, substantial volumetric expansion of 300%, and the shuttle effect induced by soluble lithium polyphosphide (LixPPs). Here, S-NRP@Ti3C2Tx composites were in situ prepared through a phosphorus-amine-based method, wherein S-doped red phosphorus nanoparticles (S-NRP) grew and anchored on the crumpled Ti3C2Tx nanosheets via Ti-O-P bonds, constructing a three-dimensional porous structure which provides fast channels for ion and electron transport and effectively buffers the volume expansion of RP. Interestingly, based on the results of adsorption experiments of polyphosphate and DFT calculation, Ti3C2Tx with abundant oxygen functional groups delivers a strong chemical adsorption effect on LixPPs, thus suppressing the shuttle effect and reducing irreversible capacity loss. Furthermore, S-doping improved the conductivity of red phosphorus nanoparticles, facilitating Li-P redox kinetics. Hence, the S-NRP@Ti3C2Tx anode demonstrates outstanding rate performance (1824 and 1090 mA h g-1 at 0.2 and 4.0 A g-1, respectively) and superior cycling performance (1401 mAh g-1 after 500 cycles at 2.0 A g-1).

Deciphering the Benefits of Coordinated Binders in Si‐Based Anodes by Combined Operando/In Situ and Ex Situ X‐Ray Micro‐ and Nano‐Tomographies

AbstractThe simple addition of a Zn(II) precursor to a preoptimized poly(carboxylic acid) binder solution enhances the electrochemical performance and cycle life of silicon‐based electrodes. The binder/cation couple forms a cross‐linked coordinated binder that plays a key role in enhancing the mechanical and chemical stability of the electrode microstructure. The impact of the addition of the Zn precursor on the microstructural evolution of the electrode during cycling is investigated at different scales (from cell/electrode to silicon particle scale) using complementary operando, in situ, and ex situ X‐ray tomography techniques. Comparative analyses conducted on the reference and with Zn electrode formulations using operando and in situ X‐ray micro‐tomography allow for monitoring of the electrode morphological deformations along with the crack pattern formation and evolution during cycling. The benefits of the precursor addition include enhancing the mechanical stability of the electrode through a strengthened microstructure more apt to maintaining its integrity, as well as a better anchoring to the current collector leading to decreased electrical disconnections and capacity fade. Moreover, complementary ex situ X‐ray nano‐tomography measurements highlight the benefits of the precursor addition in terms of chemical stability with mitigated solid electrolyte interface (SEI) formation over the electrode cycling.

Strong Magnetic Exchange Interactions and Delocalized Mn-O States Enable High-Voltage Capacity in the Na-Ion Cathode P2-Na0.67[Mg0.28Mn0.72]O2.

The increased capacity offered by oxygen-redox active cathode materials for rechargeable lithium- and sodium-ion batteries (LIBs and NIBs, respectively) offers a pathway to the next generation of high-gravimetric-capacity cathodes for use in devices, transportation and on the grid. Many of these materials, however, are plagued with voltage fade, voltage hysteresis and O2 loss, the origins of which can be traced back to changes in their electronic and chemical structures on cycling. Developing a detailed understanding of these changes is critical to mitigating these cathodes' poor performance. In this work, we present an analysis of the redox mechanism of P2-Na0.67[Mg0.28Mn0.72]O2, a layered NIB cathode whose high capacity has previously been attributed to trapped O2 molecules. We examine a variety of charge compensation scenarios, calculate their corresponding densities of states and spectroscopic properties, and systematically compare the results to experimental data: 25Mg and 17O nuclear magnetic resonance (NMR) spectroscopy, operando X-band and ex situ high-frequency electron paramagnetic resonance (EPR), ex situ magnetometry, and O and Mn K-edge X-ray Absorption Spectroscopy (XAS) and X-ray Absorption Near Edge Spectroscopy (XANES). Via a process of elimination, we suggest that the mechanism for O redox in this material is dominated by a process that involves the formation of strongly antiferromagnetic, delocalized Mn-O states which form after Mg2+ migration at high voltages. Our results primarily rely on noninvasive techniques that are vital to understanding the electronic structure of metastable cycled cathode samples.

Habitat type controls microarthropod community changes across a Magellanic sub-Antarctic elevation gradient

IntroductionElevation gradients are often used as a proxy for climate change as they allow comparisons of ecological responses over much larger temporal and spatial scales than is possible through experimental manipulations.MethodsHere, we tested how microarthropod communities (Collembola and Acari) are affected by climatic differences between sea level and 600 m a.s.l. on Navarino Island, in the Magellanic sub-Antarctic ecoregion of southern Chile (mean annual temperatures of 5.6 vs 3.1°C, respectively). We quantified microarthropod abundance, richness and community trait characteristics in dominant moss (Racomitrium lanuginosum and Polytrichum strictum) and lichen (Usnea trachycarpa, Pseudocyphellaria freycinetii and Stereocaulon alpinum) vegetation growing at both elevations. These moss and lichen genera are characterized by large morphological differences and allow testing of how habitat characteristics affect microarthropod community response across elevation gradients.ResultsCollembola and Acari community composition differed between the low and high elevation sites. Total abundance levels of Acari were maintained in each habitat across elevation, whereas Collembola richness strongly declined (50%) at high elevation in the moss habitats. Acari community differences across elevation were driven by relative abundance changes whereas the Collembola community lost species at higher elevation. An anticipated decline of smaller eudaphic Collembola at high elevation was only observed in the moss Racomitrium, reflecting potentially lower temperature buffering capacity and shelter options compared to Polytrichum. Lichens mostly supported larger epigeic species irrespective of elevation. There were no consistent patterns linking microarthropod communities with habitat water holding capacity or water loss rates across the studied habitats and elevation.DiscussionHabitat type and the genus of moss or lichen were associated with microarthropod community changes across elevation, including examples of declines, increases and no change. These findings highlight that community responses across gradients may not always relate to the generally hypothesized environmental variables (e.g. temperature variability) and that habitat characteristics should be taken into account when using elevation as a proxy for climate change.

Multicriteria selection practices in public tender evaluation process: the case of Sri Lanka

PurposeAwarding contracts based solely on the lowest price is unsuitable for every project. Consequently, most procurement systems in developed countries have progressed to the multicriteria selection practices (MSPs) for tender evaluation. MSPs consider a range of quality measures, such as completion time, life cycle cost, functional characteristics, environmental impact and innovation, alongside bid price. This study examines the prevailing MSPs in Sri Lankan public tender evaluations to enhance the effectiveness of the local tender evaluation process.Design/methodology/approachA desk study approach was employed to collect bidding documents, resulting in the identification of 66 documents. A systematic screening process was then applied to identify those bidding documents that incorporated MSPs. Subsequently, content analysis was conducted to determine the common features of the functions used in MSPs.FindingsThe study identified six primary functions related to MSPs incorporated in the bidding documents to procure building and substation projects. Three functions follow the price-to-quality method, while the remaining three follow the quality-to-price method. Among these identified functions, four functions employ objective evaluation criteria, such as thickness, capacity and operational loss. The other two functions utilize subjective evaluation criteria, such as the project’s design and technical specifications. Contract awarding will be based on either the highest score or the lowest bid, depending on the function type.Originality/valueThis study’s originality lies in exploring MSPs in the Sri Lankan public tender evaluation process and in disclosing their characteristics to promote the MSPs in Sri Lanka and developing countries.

Enhancing Tin Dioxide Anode Performance by Narrowing the Potential Range and Optimizing Electrolytes

Tin dioxide (SnO2) is a low-cost and high-capacity anode material for lithium-ion batteries, but the fast capacity fading significantly limits its practical applications. Current research efforts have focused on preparing sophisticated composite structures or optimizing functional binders, both of which increase material manufacturing costs. Herein, we utilize pristine and commercially available SnO2 nanopowders and enhance their cycling performance by simply narrowing the potential range and optimizing electrolytes. Specifically, a narrower potential range (0–1 V) mitigates the capacity fading associated with the conversion reaction, whereas an ether-based electrolyte further suppresses the volume expansion related to the alloy reaction. Consequently, this SnO2 anode delivers a promising battery performance, with a high capacity of ~650 mAhg−1 and stable cycling for 100 cycles. Our work provides an alternative approach to developing high-capacity and long-cycling metal oxide anode materials.

Enhancing the performance of LiNi0.8Mn0.1Co0.1O2-based pouch cells through advanced electrolyte additive systems for high-temperature lithium-ion batteries

Next-generation lithium-ion batteries, which achieve high energy densities and prolonged cycle performance, require cathode materials with high operating voltages and specific capacities. Because of their high capacity and operating voltage, nickel-rich layered oxides like LiNi0.8Mn0.1Co0.1O2 (NMC811) are attractive cathodes; nevertheless, they have drawbacks such capacity loss, poor cycle performance, structural instability, and thermal instability. Enhancing the stability of the NMC811 cathode-electrolyte interphase demands improvements in both cathode materials and electrolytes. This study explores the enhancement of NMC811-based battery systems through electrolyte modification, focusing on mixed additive combinations to evaluate their synergistic effects at elevated temperatures, relevant for tropical climates. A ternary additive system comprising vinylene carbonate (VC), lithium difluorophosphate (LiPO2F2), and p-toluenesulfonyl isocyanate (PTSI) in a LiPF6-based electrolyte showed significant improvements. This system mitigated capacity fading for cells cycled over 3 V–4.2 V at both 25 °C and 45 °C, outperforming the baseline electrolyte. The designed electrolyte stabilized the electrode-electrolyte interface, enhancing cell performance and the cathode's structural integrity. Notably, the graphite/NMC811 pouch cell's cycling performance showed an increase in capacity retention from 82.4% to 90.2% after 150 cycles at C/2 at 45 °C. Moreover, the deactivation of PF5 by PTSI can help to suppress the side reaction from the instability of LiPF6-based electrolytes, especially at elevated temperatures. These findings carried out from this strategic electrolyte additive system can substantially improve nickel-rich LIBs, especially in challenging thermal environments.

Legal regulation of rehabilitation in the field of health care

The article notes that the law guarantees everyone the right to health care and medical assistance. A full-scale invasion calls for the development and updating of legal acts on ensuring a person’s right to medical assistance, in particular, to the provision of rehabilitation services. It is noted that rehabilitation assistance is aimed at a number of main areas, firstly, at supporting the functions of the patient’s body during the exacerbation of chronic diseases. Secondly, for warning, early diagnosis of disorders of the organs and systems of the patient’s body. The third direction is aimed at full or partial restoration of damaged organs or systems and compensation of lost functions of affected organs or systems. The fourth direction is related to the prevention and reduction of the degree of disability. The author emphasizes that the lack of competent and effective medical rehabilitation in Ukraine is a multifactorial problem: there is an insufficient number of inpatient and outpatient rehabilitation departments; lack of medical personnel - rehabilitation specialists, psychologists; there is not enough rehabilitation equipment; there is a need for adequate educational programs for physicians. In the article, the author emphasizes that one of the tasks of the state is to help persons with disabilities realize their constitutional rights; implementation of state policy in the field of rehabilitation of persons with disabilities, support for their integration into society, and the full-scale war on the territory of Ukraine causes an increasing urgency and need for the rehabilitation of persons injured as a result of hostilities. Such factors of the population’s health, such as the increase in morbidity, injuries, temporary loss of working capacity, premature mortality of the population require the development of the rehabilitation medicine market of Ukraine and its legal regulation. The article notes that the positive aspects are the development of new medical rehabilitation technologies, including those based on telemedicine and IT technologies, the preparation of new professional standards for medical rehabilitation at the modern level in accordance with international recommendations. All this requires the effective functioning of the system, which first of all requires the improvement and development of regulatory and legal support in the field of rehabilitation.

Inset-fed quad-port hexagonal-shaped MIMO T-shaped slots on patch with slots on ground plane antenna for IoT and X-band applications

A compact and novel inset-fed hexagonal-shaped multiple input multiple output patch (IHMP) antenna with T-shaped slot is designed for IoT and X-band applications. The IHMP antenna comprises with four identical hexagonal-shaped radiating elements. In order to achieve better diversity performance and low mutual coupling, radiating elements P1, P4 are positioned side by side with ideal distance and P2, P3 are positioned opposite to P1, P4. The proposed hexagonal-shaped MIMO antenna is prototyped on low-cost Fr-4 substrate with the dimensions of 28 × 28 × 1.6 mm3. It achieves dual bandwidths (S11 < −10 dB) of 1.37 GHz (2.12–3.49 GHz) and 1.69 GHz (8.07–9.76 GHz) at 2.5 and 8.7 GHz resonating frequencies. The IHMP antenna having gain of 5.68dBi, and 5.51dBi at 2.5 and 8.7 GHz, respectively. At operating frequencies, surface current distribution and radiation patterns are examined. To calculate the diversity performance of the IHMP antenna, MIMO parameters envelope correlation coefficient < 0.05 within the band, diversity gain > 9.9 within the band, total active reflection coefficient, channel capacity loss < 0.2 bits/sec/Hz, and mean effective gain −3 dB < MEG < −6 dB are also investigated. The simulated and experimentally obtained results are presented and they are in fine agreement.

Adsorptive behavior of Rhodamine B dye over hierarchical N-doped carbons from hexamine-based complexes: Equilibrium and kinetics

Pollution from water-soluble dyes is a common issue due to high toxicity and diffiulty in degradation, and its effectively removal is critical for human health and sustainability. In this work, N-doped hierarchical carbons were derived by facile pyrolysis of Co-including hexamine-based complex using glucose as a cross-linker, showing high removal ability using Rhodamine B (RhB) as a model dye. Porous architecture and N-coordination can be easily altered by pyrolysis temperature, where the GNC-900 sample obtained at 900 °C exhibits the best removal ability even outperforming several classical carbons under equal conditions, owing to synergistic effects from large surface areas, high ratio of pyrrolic-N, enhanced interaction between RhB molecules and pore walls, and possible Co-Nx active sites. Adsorptive behaviour is better fitted by pseudo-second-order kinetic model, and the maximum RhB capacity over GNC-900 determined by Langmuir model is highly up to 400.1 mg/g, following mechanisms of pore filling, π–π conjugation, electrostatic, surface complexation and H-bonding. Thermodynamics indicate that RhB removal is exothermic and spontaneous process. Moreover, GNC-900 can be readily regenerated using ethanol and reused at least six times without notable loss in capacity. This novel method facilitates synthesis of N-doped carbons from metal-based complexes, exhibiting high efficiency as adsorbents for water remediation.

Wideband CPW fed four port MIMO antenna based microwave sensor for deep brain temperature measurement

This study presents a wideband CPW fed four-port multi-input multi-output (MIMO) antenna-based microwave sensor for measuring deep brain temperature inside human head. The range of frequency is from 5.45 to 8.56 GHz at the resonance frequency of 7.25 GHz. Coplanar Waveguide (CPW) fed approach on a low-cost FR4 substrate is used in designing the planar antenna. The presented antenna is compact, having overall dimensions of 40 × 40 × 1.6 mm3. In the operational frequency range, the obtained diversity performance for MIMO antenna shows Envelope Correlation Coefficient (ECC) < 0.05, Diversity Gain > 9.95, total active reflection coefficient (TARC ) < −13 dB and channel capacity loss (CCL) < 0.125 bits/S/Hz. For deep brain temperature measurements, the proposed sensor provides electric field of 3.92 V m−1 and specific absorption rate (SAR) value of 0.16 W kg−1 at the 9 mm distance inside the human head Phantom. The proposed sensor is capable of measuring 0.1 °C change in temperature at 10 W of input power for 60 s when all four ports are active.

Ulcerative colitis: definition, epidemiology, pathogenesis, clinic, diagnosis, follow-up. Lecture. Part I

Inflammatory bowel diseases (IBD) are currently one of the most difficult problems in modern global internal medicine in general and in gastroenterology in particular. The diseases demonstrate a relapsing, progressive nature, significant decrease in the quality of life, physical activity of patients, complications from other organs and systems of the human body, a decrease or even loss of working capacity, difficulties in socialization and creating a family. An insufficiently predicted course of the disease, acute or chronic intestinal complications can lead to surgical interventions. According to the severity of the course, the frequency of disability, complications, including those, that require surgical intervention; in terms of the economic costs of the health care system, IBDs are ahead of a number of other widespread diseases of digestive organs. The variety of clinical, anatomical (in particular, localization and extend of damage to the Gut), endoscopic signs of the disease in combination with different degrees of severity and activity of the disease, the presence of local and systemic extraintestinal manifestations determine difficulties in early establishing the diagnosis, in differential diagnosis and in choosing an effective and safe therapy, which is prescribed for the purpose of not only achieving, but also further maintaining a stable remission of the disease.In the vast majority of patients, the disease is characterized by a chronic relapsing course and requires long­­term, constant, often life­­long drug treatment with the use of drugs from various pharmacological groups, including combination therapy. An active search for predictably effective drugs for the treatment for IBD continues at the present time. According to the new International Classification of Diseases, 11th revision (2022), three diseases are included in the IBD group: ulcerative colitis (UC), Crohn’s disease (CD) and indeterminate colitis, i.e. a disease in which it is impossible to clearly determine whether it is UC or CD of the colon. In modern medicine, there is a tendency towards greater clarity and conciseness in the formulation of diagnoses, examination algorithms and treatment regimens. Inflammatory bowel disease remains diseases with many unknowns, both in terms of establishing a clear diagnosis and in terms of prognosis and predictability of the consequences of drug therapy.

Damage and energy characteristics of coal rock combinations with inclined coal seams under axial loading

A single load compression test of rock-coal-rock assemblages (RCRs) containing coal bodies with different inclinations was carried out with the research background of mining deep, large-steep coal seams. It was found that the larger the inclination angle of the coal body in the RCR samples, the larger the compaction stage of the samples and the smaller the uniaxial compressive strength value. In addition, both the maximum acoustic emission (AE) energy of the samples and the cumulative AE energy at the moment of destruction decreased with the increase of the inclination angle of the coal body in the form of exponential relativities. Also, the input energy and ultimate elastic energy of the samples at the peak stress moment decreased with increased inclination angle of the coal body. Furthermore, both of them changed with the inclination angle of the coal body in accordance with the exponential relationship; meanwhile, when the applied load exceeded the peak strength, the dissipative energy of the RCR samples increased rapidly due to the loss of load-bearing capacity. At the peak moment, the percentage of dissipated energy of the samples increased exponentially with the increase of the inclination angle of the coal body. This study has certain reference significance for the prevention and control of dynamic disasters during the mining of large angle coal seams.

Lithium-rich manganese-based layered oxide cathode materials for lithium-ion batteries modified by MoS2 coatings with two-dimensional graphene-like structures

Lithium-rich manganese-based layered oxide cathode materials (LRMCs) have some unique advantages such as high theoretical capacity (≥ 250 mAh g−1) and high energy density. Therefore, they are deemed as a kind of cathode material for lithium-ion batteries with an excellent prospect of application. However, the redox of oxygen anion is able to generate irreversible lattice oxygen loss, leading to irreversible loss of capacity, bringing about a sharp drop of working voltage, and seriously restricting the commercialization of LRMCs. In this paper, MoS2 coating with two-dimensional graphene-like structure was coated on the surface of LRMCs materials for improving the cycling stability and rate performance. The MoS2 coating can provide a two-dimensional diffusion channel for the migration of lithium-ions, which facilitates the fast release of lithium-ions during cycling process. The results show that the first discharge capacity, initial Coulomb efficiency and rate performance of LRMCs are improved. When the current density is 1 C, the first discharge specific capacity of LRMCs@MoS2 reaches 227.69 mAh g−1, and the capacity retention ratio is 84.98 % after 100 cycles. When the current density is 5 C, it can still provide a discharge specific capacity of 137.87 mAh g−1, demonstrating excellent electrochemical performance. This study comes up a simple and practical idea to realize the modification of cathode materials for high performance lithium-ion batteries.

Exopolysaccharide (EPS) Produced by Leuconostoc mesenteroides SJC113: Characterization of Functional and Technological Properties and Application in Fat-Free Cheese

A Leuconostoc mesenteroides strain (SJC113) isolated from cheese curd was found to produce large amounts of a mucoid exopolysaccharide (EPS). An analysis revealed the glucan nature of the EPS with 84.5% (1→6)-linked α-d-glucose units and 5.6% (1,3→6)-linked α-d-glucose units as branching points. The EPS showed 52% dextranase resistance and a yield of 7.4 ± 0.9 g/L from MRS medium supplemented with 10% sucrose within 48 h. Ln. mesenteroides SJC113 was also characterized and tested for the production of EPS as a fat substitute in fresh cheese. Strain SJC113 showed high tolerance to a wide range of NaCl concentrations (2, 5 and 10%), high β-galactosidase activity (2368 ± 24 Miller units), cholesterol-reducing ability (14.8 ± 4.1%), free radical scavenging activity (11.7 ± 0.7%) and hydroxyl scavenging activity (15.7 ± 0.4%). The strain had no virulence genes and was sensitive to clinically important antibiotics such as ampicillin, tetracycline and chloramphenicol. Ln. mesenteroides SJC113 produced highly viscous EPS during storage at 8 °C in skim milk with 5% sucrose. Therefore, these conditions were used for EPS production in skim milk before incorporation into fresh cheese. Four types of fresh cheese were produced: full-fat cheese (FF) made from pasteurized whole milk, non-fat cheese (NF) made from pasteurized skim milk, non-fat cheese made from skim milk fermented with Ln. mesenteroides without added sugar (NFLn0) and non-fat cheese made from skim milk fermented with Ln. mesenteroides with 5% sucrose (NFLn5). While the NF cheeses had the highest viscosity and hardness, the NFLn5 cheeses showed lower firmness and viscosity, higher water-holding capacity and lower weight loss during storage. Overall, the NFLn5 cheeses had similar rheological properties to full-fat cheeses with a low degree of syneresis. It was thus shown that the glucan-type EPS produced by Ln. mesenteroides SJC113 can successfully replace fat without altering the texture of fresh cheese.

Metamaterial inspired superstrate loaded miniaturized quad port MIMO antenna for 5G C-band applications

This paper proposes a new quad-port Multiple-Input-Multiple-Output antenna with a unique Maze structure Epsilon Negative (ENG) Metamaterial superstrate for 5G NR C-band applications. The suggested 2x2 MIMO antenna has four microstrip antennas with a C-shaped stub inside the slot arranged orthogonally on a FR4 substrate. The overall dimension of the proposed 2x2 MIMO antenna is 0.62λ0 x 0.62λ0 x 0.02λ0, where λ0 is the free space wavelength at 3.7 GHz. The proposed MIMO antenna has excellent impedance matching over a bandwidth of 32% (3.2 GHz–4.4 GHz). The proposed antenna incorporates a superstrate layer composed of modified maze-structured metamaterial elements with a unit cell size of 0.16λ0 x 0.16λ0 x 0.02λ0 on a single-layer FR4 substrate to enhance the antenna's gain, improve isolation properties, and achieve size reduction. By strategically placing the metamaterial superstrate, it reduces the mutual coupling between the antennas and enhances peak isolation of < −30 dB. In order to accomplish the goals of isolation and gain improvement, the metamaterial superstrate is positioned 10.5 mm (0.13λ0) above the MIMO components. Furthermore, it attains a 3.54 dB peak realized gain, which is enhanced by 162% across the frequency ranges, and the overall size of the MIMO antenna is reduced to approximately 17%. Adequate values for factors such as the diversity gain, envelope correlation coefficient, channel capacity loss, and total active reflection coefficient are also determined for the MIMO antenna performance. The design prototype of the proposed antenna is built and verified by measurements that reveal a strong correlation with the simulation's output.

Rapid and efficient carbon dioxide capture through benzene-1,4-diamine based hierarchical porous hyper-cross-linked polymers

Carbon dioxide (CO2) emission causes global warming which has been the greatest challenge for humanity since last decade. Herein, we developed nitrogen and phosphorus rich hyper cross-linked polymers for CO2 capture, designated as BDA-HCP-1 and BDA-HCP-2 (benzene-1,4-diamine based hyper cross-linked polymers) having BET surface area 294.5904 m2g-1 and 519.6918 m2g-1 respectively. The pore width range of BDA-HCP-1 and BDA-HCP-2 is 0–25 nm and 0–15 nm and pore volume of BDA-HCP-1 and BDA-HCP-2 is 0.01–0.18cm3/g and 0.01–0.25 cm3/g, respectively.Total pore volume, studied using DFT, is 0.20100 cm3/g for BDA-HCP-1 and 0.27973 cm3/g for BDA-HCP-2. BJH cumulative pore volume of BDA-HCP-1 is 0.113023 cm3/g and BDA-HCP-2 is 0.284733 cm3/g. The BDA-HCP-1and BDA-HCP-2 were synthesized by replacement of chlorines of hexachlorocyclophosphazenes (HCCP) and phosphorousdichlorophosphazenes (PDCP) with bezene-1,4-diamine to form linear and cyclic polyphosphazenes, which are later cross-linked through Friedal crafts reaction to form hyper cross-linked polymers. The maximum CO2 adsorption quantity of BDA-HCP-1 is 48.62 cm3/g (CO2 weight adsorbed 9.070 % with equilibrium time 8.16 min) at 273K/1 bar and 37.96 cm3/g (weight adsorbed 7.15 % with equilibrium time 8.25 min) at 298K/1 bar that gives adsorption capacity of 2.14 mmol/g and 1.69 mmol/g, respectively. Adsorption capacity of BDA-HCP-2 is 2.30 mmol/g and 2.13 mmol/g at 273 K/1 bar and 298 K/1 bar respectively. It is calculated from maximum CO2 adsorption quantity of 51.6 cm3/g (weight adsorbed 9.83 % with equilibrium time 11.4 min, at 273 K/1 bar) and 47.7 cm3/g (weight adsorbed 9.25 % with equilibrium time 8.45 min, at 298 K/1 bar) respectively. Both BDA-HCPs can be reused with minor loss in adsorption capacity (2 and 1 %), which makes them excellent candidates to use on industrial scale applications. Adsorption isotherm study (Langmuir, Freundlich, and Temkin) and Kinetics study (pseudo first order and pseudo second order) reveals that this study fit best for Freundlich isotherms and pseudo first order kinetic model for both BDA-HCPs. This research contributes valuable insights into the design of hyper cross-linked materials with high surface area, good pore volume, excellent thermal stability and promising gas adsorption capacities particularly for addressing environmental pollution challenges related to CO2 emissions.