Lamina Shape Research Articles

Ultra-ventilated sound absorption metamaterial lamina

We propose a lamina-shaped metamaterial absorber based on the coherently coupled weak resonances of high-order Helmholtz resonators in this work. Such an ultra-thin lamina metamaterial can achieve broadband tunable absorption (maximal absorption >0.9), which exhibits near-perfect ventilation performance (ventilated area ratio >0.8, ratio of wind velocity >0.95). Benefiting from coherently coupled weak resonances between units with different structure parameters, the lamina metamaterial presents a broadband absorption (506–659 Hz with 2 × 3 units and 480–679 Hz with 2 × 4 units). The ultra-thin and simple structure shape of this sound absorption metamaterial lamina leads to not only an efficient ventilation performance but also high potential value in various scenarios of ventilated sound absorption, especially in ventilation tubes with high noise.

Probe-free optical chromatin deformation and measurement of differential mechanical properties in the nucleus.

The nucleus is highly organized to facilitate coordinated gene transcription. Measuring the rheological properties of the nucleus and its sub-compartments will be crucial to understand the principles underlying nuclear organization. Here, we show that strongly localized temperature gradients (approaching 1°C/µm) can lead to substantial intra-nuclear chromatin displacements (>1 µm), while nuclear area and lamina shape remain unaffected. Using particle image velocimetry (PIV), intra-nuclear displacement fields can be calculated and converted into spatio-temporally resolved maps of various strain components. Using this approach, we show that chromatin displacements are highly reversible, indicating that elastic contributions are dominant in maintaining nuclear organization on the time scale of seconds. In genetically inverted nuclei, centrally compacted heterochromatin displays high resistance to deformation, giving a rigid, solid-like appearance. Correlating spatially resolved strain maps with fluorescent reporters in conventional interphase nuclei reveals that various nuclear compartments possess distinct mechanical identities. Surprisingly, both densely and loosely packed chromatin showed high resistance to deformation, compared to medium dense chromatin. Equally, nucleoli display particularly high resistance and strong local anchoring to heterochromatin. Our results establish how localized temperature gradients can be used to drive nuclear compartments out of mechanical equilibrium to obtain spatial maps of their material responses.

Comparative heat transfer analysis of 𝑨𝒍𝟐𝑶𝟑 and 𝑪𝒖 nanoparticles based in 𝑯𝟐𝑶 nanofluids flow inside a C-shaped partially heated rectangular cavity

The aim of the current study is to investigate the heat transfer performance of 𝐴𝑙2𝑂3 and 𝐶𝑢 nanoparticles suspended based in 𝐻2𝑂 nanofluids inside a partially heated C-shaped enclosure. The governing equations for heat and flow transfer are solved using the Finite Element Method. Heat transmission is affected by the type and form of nanoparticles. To study the improved heat transfer performance, four different shapes of nanoparticles-spherical, cylindrical, column, and lamina-have been used. The investigation showed that among the considered shapes of nanoparticles, the lamina shape of nanoparticles performed best. Considering lamina nanoparticles, in comparison to the simple nanofluids 𝐴𝑙2𝑂3−𝐻2𝑂 and 𝐶𝑢−𝐻2𝑂 the hybrid nanofluid 𝐴𝑙2𝑂3−𝐶𝑢−𝐻2𝑂 provides the enhanced heat transfer rate. The heat transfer is governed by convection at a higher Rayleigh number. On the other hand, the heat transfer rate is decreasing by increasing the impact of the magnetic field. For the increased heat transfer rate, the best choice is lamina nanoparticles and hybrid nanofluid 𝐴𝑙2𝑂3−𝐶𝑢−𝐻2𝑂.

Фармакогностическое исследование сырья Nepeta pannonica

Фармакогностический анализ лекарственного растительного сырья является важным этапом введения вида в официальное использование. Объектом исследования являлись надземные органы Nepetapannonica(семейство Lamiaceae), для которого выполнен макро- и микроскопический анализ. Определены следующие диагностические признаки на макроскопическом уровне: лист — форма листовой пластинки, тип жилкования; стебель — тип ветвления побега, окраска, супротивное расположение листьев, слабое опушение; соцветие — расположение цветков; чашечка цветка — форма зубцов, тип опушения, мелкая ребристость; венчик цветка — форма и размеры, окраска. В качестве микроскопических признаков сырья определены форма клеток эпидермиса верхней и нижней сторон, участков над жилками; диацитные устьица, наличие мелких многоклеточных трихом и крупных эфирномасличных железок в строении листа, стебля, чашечки и венчика цветка; разделение мезофилла на столбчатую и губчатую ткани на поперечном срезе листа.

Numerical investigation and analysis of heat transfer and thin film flow of Fe3O4 and Al2O3 nanoparticles dispersed in H2O over vertical stretching sheet

Purpose This article presents a numerical investigation of thin film flow and heat transfer for lamina, tetrahedron, and hexahedron-shaped nanomaterials of F e 3 O 4 and A l 2 O 3 over a time-dependent radially vertical stretching surface. Moreover, magnetohydrodynamics and viscous dissipation effects are also incorporated. Thin-film treatment is especially beneficial in nanotechnology. As a result, the current study’s findings will be useful in a variety of thin film phenomena involving nanoparticles. F e 3 O 4 thin films have considerable potential in a variety of applications, including sensors and batteries. Aluminum oxide nanoparticles have two key applications: medicines and the materials manufacturing industries. Methodology A similarity transformation is employed to produce the nonlinear governing system of equations, which is numerically solved using the BVP4C method in MATLAB. As film thickness depends on the unsteadiness parameter, with an increase in the parameter causing a decrease in film thickness ( β ) , velocity, and temperature. Findings The lamina and hexahedron shapes provide maximum and minimum film thickness for F e 3 O 4 and A l 2 O 3 both nanoparticles, while the hexahedron and lamina shapes generate maximum and minimum skin friction. The Nusselt numbers exhibit the opposite effect. The highest and lowest heat transfer rates are noticed for lamina and hexahedron-shaped nanoparticles of A l 2 O 3 .

Computational analysis of hybrid nanoliquid flow over an exponentially elongating sheet influenced by oblique Lorentz force with viscous-Joule dissipation: Role of nanoparticle shape factor

This article mainly examines the influences of an oblique Lorentz force on H2O-based hybrid nanoliquid flow over a over a permeable and exponentially elongating surface embedded in a uniform porous medium. The nanoliquid contains Cu and Al2O3 as suspended nanoparticles of varying shapes (spherical, blade and lamina). Further, the significance of viscous-Joule dissipation, nonlinear thermal radiation, and an internal heat source is also considered. Moreover, Navier’s velocity slip and thermal jump conditions are imposed at the surface boundary. Studying such a fluid flow problem becomes essential because of various industrial devices and technological processes, viz., the production of polymer, manufacturing of food products, metallurgical processes, cooling of electronic chips and solar cells, nuclear power reactors and several other devices like thermistors, glass fiber, electric fuses, gas turbines, etc. A suitable similarity transformation has been utilized to transform the governing set of equations into dimensionless form. The resulting highly nonlinear boundary value problem is solved numerically using Runge–Kutta–Fehlberg formula-based shooting method. In addition, secant iteration is employed to modify the guesses for missing initial conditions. The outcomes of the study are demonstrated and displayed through graphs and tables. Furthermore, a quadratic regression analysis is carried out to illustrate the dominant behavior of the relevant factors on the local drag coefficient and Nusselt number. The angle of inclination of applied magnetic field has the tendency to accelerate the flow. Compared to blade and lamina shapes nanoparticles, nanofluid temperature is higher for spherical nanoparticles.

Two new species of Begonia (Begoniaceae) from Aurora Memorial National Park, Luzon Island, Philippines

Begonia masilig and Begonia akaw, both endemic to Aurora Memorial National Park, Luzon, Philippines, are described as species new to science. Begonia masilig is similar to B. droseroides in its rhizomatous habit and glandular trichomes on the inflorescence, but differs in lamina shape and overall size, and the vestiture of stipule, lamina margin, and outer tepals of staminate flowers. Begonia akaw is similar to B. ramosii in its short erect habit, ovate lamina and congested terminal inflorescence with 2-tepaled staminate flowers, but differs in inflorescence size and arrangement, and bract and ovary shape. Both new species are here proposed to be Endangered (EN) as per IUCN criteria.

Comparative thermal analysis of Nickel and Tantalum based hybrid nanofluid using constant proportional Caputo and Atangana–Baleanu operators with time-controlled condition

The main purpose of this research work is to examine how the immersion of nickel and tantalum nanoparticles in water affects the flow and thermal properties of water, with the aim of anticipating potential enhancements. The investigation pertains to the flow behavior of a hybrid nanofluid over an extensively elongated vertical surface under the influence of a condition that varies with time. The phenomenon of heat transfer transpires due to the combined effects of natural convection and thermal radiation. An in-depth comprehension of flow patterns and heat transfer over a vertical surface is essential for optimizing heat exchange processes, designing efficient cooling systems, and enhancing overall energy efficiency. It also helps in climate modeling, weather prediction, and the improvement of the performance of solar thermal systems. The basic model is generalized using Atangana–Baleanu (AB) and constant proportional Caputo (CPC) operators. This generalization leads to the development of two different fractional settings for which separate mathematical analyses are performed. With the help of some new unit-independent quantities, exact solutions for both fractional frameworks are computed using the Laplace transform. For the elucidation of changes in velocity and thermal fields due to different physical effects, several graphical and tabular representations are produced. The outcomes illustrate that the incorporation of uniform concentrations of nickel and tantalum nanoparticles in water leads to raising its thermal efficacy up to 40.39%. The nanoparticles consisting of lamina shapes are observed to produce the maximum amelioration in thermal features. The CPC model based profiles of flow and temperature fields are lower than those procured via the AB model. As a result of nanoparticles’ intrinsic characteristics, the insignificant heat transfer capability of water is greatly amplified, leading to a notable boost in its thermal performance. Thus, the examined hybrid nanofluid can be used as a viable alternative to water in various engineering applications.

Exact solutions via Prabhakar fractional approach to investigate heat transfer and flow features of hybrid nanofluid subject to shape and slip effects

The core devotion of this study is to develop a generalized model by means of a recently proposed fractional technique in order to anticipate the enhancement in the thermal efficiency of engine oil because of the dispersion of graphene and magnesia nanoparticles. In addition to investigating the synergistic attributes of the foregoing particles, this work evaluates shape impacts for column, brick, tetrahedron, blade, and lamina-like shapes. In the primary model, the flow equation is coupled with concentration and energy functions. This classical system is transmuted into a fractional environment by generalizing mathematical expressions of thermal and diffusion fluxes by virtue of the Prabhakar fractional operator. In this study, ramped flow and temperature slip conditions are simultaneously applied for the first time to examine the behavior of a hybrid nanofluid. The mathematical analysis of this problem involves the incorporation of dimension-independent parameters into the model and the execution of the Laplace transform for the consequent equations. By doing so, exact solutions are derived in the form of Mittag–Leffler functions. Multiple illustrations are developed by dint of exact solutions to chew over all aspects of temperature variations and flow dynamics. For the preparation of these illustrations, the details of parametric ranges are as follows: 0.00 le varUpsilon le 0.04, 2.0 le Gr_1 le 8.0, 0.5 le Sc le 2.0, 0.1 le uptau le 4.0, 0.1 le d le 0.6, 0.2 le lambda _1 le 1.5, and 1.0 le Gr_2 le 7.0. The contribution of differently shaped nanoparticles, volume proportions, and fractional parameters in boosting the heat-transferring attributes of engine oil is also anticipated. In this regard, results for Nusselt number are provided in tabular form. Additionally, a brief analysis of shear stress is carried out for fractional parameters and various combinations of magnesia, graphene, and engine oil. This investigation anticipates that engine oil’s hybridization with magnesia and graphene would result in a 33% increase in its thermal performance, which evidently improves its industrial significance. The enhancement in Schmidt number yields an improvement in the mass transfer rate. An increment in collective volume fraction leads to raising the profile of the thermal field. However, the velocity indicates a decreasing behavior. Nusselt number reaches its highest value (Nu=8.1363) for the lamina shape of considered particles. When the intensity of the buoyancy force augments, it causes the velocity to increase.

Nanoparticles impacts on natural convection nanofluid flow and heat transfer inside a square cavity with fixed a circular obstacle

Many significant applications may be acquired in specific nanoparticle shapes as well as size range or size. The shape of nano-sized particles is significant in every field of trace metal detection, for biomolecular assays, molecular labeling and the application of nanotechnology. The nanoparticle's shape effects are very noteworthy on the thermal conductivity of suspension. The main focus of the current study is to elaborate the nanoparticles shape impacts on nanofluid flow in a lid-driven square cavity with a fixed circular obstacle at the center. The top wall of the square cavity is adiabatic and moving. The circular cavity and bottom wall of the cavity is heated, while the remaining walls of the cavity are cold. The diamond-water nanofluid contained three kinds of nanoparticles shape namely Sphere, Column (nonspherical) and Lamina (nonspherical). The flow-modeled phenomena is governed in form of coupled partial differential equations and is tackled with finite element method (FEM). The flow distribution analysis is deliberated in form of streamlines, isothermal contour patterns, velocity distribution, temperature distribution, kinetic energy and Nusselt number. The graphical results indicate that the Lamina (nonspherical) shape nanoparticles have higher performance in (diamond-water) temperature distribution and heat transfer.

Cyrtomium calcis sp. nov. and six new records of the shield fern family (Dryopteridaceae) from Vietnam

We describe a new species of Cyrtomium, C. calcis, from northern Vietnam and southern China, and report new records of six species in two fern genera, Arachniodes and Polystichum, of Dryopteridaceae, i.e., Arachniodes amabilis (from Lamdong Province), A. amoena (Quangtri Province), A. fengii (Nghean Province), A. globisora (Thanhhoa, Quangtri, and Laocai provinces), and A. nigrossora (Vinhphuc Province), and Polystichum ariticulatipilosum (Hagiang Province). The new species of Cyrtomium most closely resembles C. pachyphyllum, but can be distinguished from the latter in the shape of petiole scales, number of lateral pinna pairs, venation, and lamina shape. Detailed description, images, notes, type information, examined specimens, distribution, and habitat are provided for the new species and new records. The status of the new species is provisionally assessed here as endangered (EN) following the IUCN Categories and Criteria.

Small Leaves, Big Diversity: Citizen Science and Taxonomic Revision Triples Species Number in the Carnivorous Drosera microphylla Complex (D. Section Ergaleium, Droseraceae).

The carnivorous Drosera microphylla complex from southwest Western Australia comprises a group of rare, narrowly endemic species that are potentially threatened by habitat destruction and illegal collection, thus highlighting a need for accurate taxonomic classification to facilitate conservation efforts. Following extensive fieldwork over two decades, detailed studies of both Australian and European herbaria and consideration of both crucial contributions by citizen scientists and social media observations, nine species of the D. microphylla complex are here described and illustrated, including four new species: D. atrata, D. hortiorum, D. koikyennuruff, and D. reflexa. The identities of the previously described infraspecific taxa D. calycina var. minor and D. microphylla var. macropetala are clarified. Both are here lectotypified, reinstated, and elevated to species rank. A replacement name, D. rubricalyx, is provided for the former taxon. Key morphological characters distinguishing the species of this complex include the presence or absence of axillary leaves, lamina shape, petal colour, filament shape, and style length. A detailed identification key, comparison figures, and a distribution map are provided. Six of the nine species are recommended for inclusion on the Priority Flora List under the Conservation Codes for Western Australian Flora and Fauna.

SQUAMOSA PROMOTER BINDING PROTEIN-LIKE 9 and 13 repress BLADE-ON-PETIOLE 1 and 2 directly to promote adult leaf morphology in Arabidopsis.

The juvenile-to-adult phase transition during vegetative development is a critical decision point in a plant's life cycle. This transition is mediated by a decline in levels of miR156/157 and an increase in the activities of its direct targets, SQUAMOSA PROMOTER BINDING PROTEIN-LIKE (SPL) proteins. In Arabidopsis, the juvenile-to-adult transition is characterized by an increase in the length to width ratio of the leaf blade (a change in the distal region of a leaf), but what mediates this change in lamina shape is not known. Here, we show that ectopic expression of SPL9 and SPL13 produces enlarged and elongated leaves, resembling leaves from the blade-on-petiole1 (bop1) bop2 double mutant. The expression of BOP1/BOP2 is down-regulated in successive leaves, correlating with the amount of miR156 and antagonistic to the expression of SPL9 and SPL13 in leaves. SPL9 and SPL13 bind to the promoters of BOP1/BOP2 directly to repress their expression, resulting in delayed establishment of proliferative regions in leaves, which promotes more blade outgrowth (the distal region of a leaf) and suppresses petiole development (the proximal region of a leaf). Our results reveal a mechanism for leaf development along the proximal-distal axis, a heteroblastic character between juvenile leaves and adult leaves.

Shape Effect of Nanoparticles on Nanofluid Flow Containing Gyrotactic Microorganisms

In this paper, we discussed the effect of nanoparticles shape on bioconvection nanofluid flow over the vertical cone in a permeable medium. The nanofluid contains water, Al2O3 nanoparticles with sphere (spherical) and lamina (non-spherical) shapes and motile microorganisms. The phenomena of heat absorption/generation, Joule heating and thermal radiation with chemical reactions have been incorporated. The similarity transformations technique is used to transform a governing system of partial differential equations into ordinary differential equations. The numerical bvp4c MATLAB program is used to find the solution of ordinary differential equations. The interesting aspects of pertinent parameters on mass transfer, energy, concentration, and density of the motile microorganisms’ profiles are computed and discussed. Our analysis depicts that the performance of sphere shape nanoparticles in the form of velocity distribution, temperature distribution, skin friction, Sherwood number and Motile density number is better than lamina (non-spherical) shapes nanoparticles.

The impacts of shape factor and heat transfer on two-phase flow of nano and hybrid nanofluid in a saturated porous medium

The focus of this article is to obtain the effect of shape factor of the hybrid nanoparticles on the convective heat and mass transference of two immiscible fluids in an inclined duct by employing the perturbation technique. The hybrid nanoparticle of Carbon Nanotube & Sodium alginate is being used with Silicon oil as the base fluid to study the heat and mass phenomena due to the soret effect, viscous dissipation, Darcy and Thermal diffusion. The physical flow problem is then modelled into a set of differential equations. The system of equations is solved analytically to obtain various graphical and numerical results for analyzing the impact of various material parameters on velocity and thermal field. The heat transfer rate and skin friction analysis for the flow dynamics are also investigated. It is observed that the shape factor enhances the fluid flow and temperature distribution. In specific lamina shape particles have better performance comparatively, significance of the soret number can also be observed.

Croton nagaoi, a new species of Euphorbiaceae from southern Laos

Croton nagaoi (Euphorbiaceae) is described based on a specimen collected from the basin of the Bolaven Plateau, southern Laos. It is most similar to Croton thorelii Gagnep. of Laos, Cambodia, Thailand and Vietnam in size and shape of lamina, short petioles less than 1 cm long, and basal glands lateral on the abaxial midrib base, but different in having densely stellate hairy lower leaf surface (vs. very sparsely pubescent and glabrescent in C. thorelii), smaller sepals and petals of staminate flowers (sepals and petals ca. 2.2 mm long vs. 3 mm long and 2.5 mm long, respectively), and the presence of petals in pistillate flowers (vs. absent). Morphological descriptions, photographs, vernacular name, and preliminary conservation status are provided for C. nagaoi.

Sinosenecio yangii (Asteraceae), a new species from Guizhou, China

A new species Sinosenecio yangii D.G. Zhang & Q. Zhou (Asteraceae, Senecioneae) from Guizhou Province, China, is described and illustrated based on its morphological characteristics and molecular evidence. It closely resembles S. confervifer and S. guangxiensis, the former in the scapigerous habit and smooth and glabrous achene surface, the latter in the calyculate involucre and purple abaxial leaf surface, and both in the shape and indumentum of leaf lamina, but differs markedly from the latter two in having fewer capitula and epappose achenes. Phylogenetic analysis based on nrITS and ndhC-trnV sequences shows that this new species belongs to the S. latouchei clade and is sister to S. guangxiensis with moderate support.

Sinosenecioyangii (Asteraceae), a new species from Guizhou, China.

A new species Sinosenecioyangii D.G. Zhang & Q. Zhou (Asteraceae, Senecioneae) from Guizhou Province, China, is described and illustrated based on its morphological characteristics and molecular evidence. It closely resembles S.confervifer and S.guangxiensis, the former in the scapigerous habit and smooth and glabrous achene surface, the latter in the calyculate involucre and purple abaxial leaf surface, and both in the shape and indumentum of leaf lamina, but differs markedly from the latter two in having fewer capitula and epappose achenes. Phylogenetic analysis based on nrITS and ndhC-trnV sequences shows that this new species belongs to the S.latouchei clade and is sister to S.guangxiensis with moderate support.

Phenotypes of Citrus Sp. As a Selected in Dwarf Rootstock Material Regard to Abiotic Stress Tolerance

Research on abiotic stress tolerant horticultural plants has been widely carried out. However, there has not been much research on the citrus phenotype with rootstock as planting material, which has advantages in overcoming abiotic stress and dwarf performance. This research provides citrus rootstock that is tolerant to some of the marginal land in Indonesia especially on drought, salinity, waterlogging, and acidity. This morphological research was conducted at Punten Experimental Garden in Batu city, Indonesia. Anatomical observations were carried out in the laboratories of Indonesian Balitjestro and Universitas Brawijaya. This has done pre-treatment selection lasted for 8 months and then abiotic stress treatment lasted for 2 months, from July to September 2021. This study consisted of 15 treatment combinations: three rootstock varieties, i.e., Citromello (Cit), Volkameriana (Volk), and Cleopatra mandarin (CM), and five abiotic stress treatments, i.e., control, PEG 10%, NaCl 3.5%, waterlogging 150% FC, and 9 mM Al2SO4. The results showed that abiotic stress, especially NaCl and waterlogging, caused phenotypic changes such as in leaf shape, i.e., leaf lamina shape, reduced leaf area, chlorophyll content, stomata density, and canopy diameter compared to other abiotic stresses. The best stomatal density and open stomata percentage were for Cleopatra mandarin (CM). This was also shown by the increase in proline content when plants are subjected to abiotic stresses, especially in Cleopatra mandarin under NaCl stress, Volkameriana under Al2SO4 stress, and Citromello under waterlogging (WL). The palisade size decreased, its vascular bundles in the leaves increased, and the pore distribution changed. The results showed all rootstock candidates were resistant to several abiotic stresses and had dwarf performance. It can be concluded that the best tolerant of abiotic stress rootstock variety of abiotic stress is Cleopatra mandarin, while Volkameriana and Citromello are better tolerant on acidic soil.

Analysis of energy and momentum transport for Casson nanofluid in a microchannel with radiation and chemical reaction effects

ABSTRACT The study of Casson nanofluid plays a prominent role in biomedicine, magnetic resonance imaging and thermal enhancement of energy system due to the eminence of its thermophysical properties. By considering various practical applications, in this article the steady, laminar, electromagnetohydrodynamic flow of Casson nanofluid across parallel plates with the effect of Hall current, chemical reaction, modified Darcy's law and Joule heating have been taken into consideration. Gold and Silver nanoparticles of sphere shape are considered in blood taken as conventional base fluid with volume fraction of 1%. However, for comparison, other shapes of nanoparticles are also considered. The system of dimensional governing equations of nanofluid are converted to dimensionless set of equations using pertinent non-dimensional quantities. The analytical solutions are presented for the system of equations. The obtained exact solution for nanofluid velocity, nanofluid temperature, nanofluid concentration, Sherwood number, Nusselt number and shear stress are displayed graphically to see the effectiveness of sundry parameters. It is found that the velocity and temperature decreases, while concentration of Ag-blood and Au-blood rises with increased values of nanoparticle volume fraction. Performance of nanoparticle of sphere shape is lowest and lamina shape is highest in terms of heat and mass transfer. The present study may be useful in further studies of tumour therapy, biomedical imaging and cancer therapy.