Basic Structural Parameters Research Articles

Effect of Fabric Structural Parameters on Various Comfort Properties of Automobile Seat Cover Fabrics

In this study, the effects of the structural parameters forming automobile seat cover fabrics on the comfort properties (such as water vapor permeability, air permeability and thermal resistance properties of fabrics) that may affect the vehicle usage performance of the person were examined. The seat cover fabrics used in the experimental study had not undergone any special finishing processes and it was aimed to evaluate the direct (without any special treatment) effect of the basic structural parameters that make up the fabric. Thus, it was considered that the fabrics used in the seat covers during the usage or after the treatments such as seat cleaning would create an important design input in terms of the breathability of the seat cover fabric and its sustainability throughout the lifetime of the car. As a results of this research, it was observed that thickness, weight per unit area and weave structure of seat cover woven fabrics have an important effect on the water vapor permeability, air permeability and thermal resistivity properties of the fabrics.

Optimization and synthesis of a cam-linkage mechanism with a swing follower with variable pivot

In this paper, a cam-linkage mechanism with a swing follower with variable pivot has been studied. In this mechanism, the pivot of the swing follower is installed on a slider with an adjustable track direction, the follower performs a complex planar motion, and the motion range of the output angle can be adjusted according to the output requirements. In order to synthesize this mechanism, firstly, the relevant model is established and the basic structural parameters are optimized by considering the assembly conditions and the pressure angle under the limit position of the movement track of the follower mounting slider. Subsequently, the inverse method and the envelope theory are employed to derive the cam contour coordinates. Finally, the corresponding follower motion law is selected, the corresponding cam contour coordinates are calculated, and the entire cam contour curve is obtained using spline interpolation. An automatic design system for cam contours is developed. The processes are carried out through design examples and verified through motion simulations and prototype experiment. The present work can enrich the design theory of cam-linkage mechanisms.

Effects of degree of deacetylation on hemostatic performance of partially deacetylated chitin sponges

Chitin/chitosan hemostatic materials have long been studied for uncontrolled hemorrhage, an urgent clinical problem due to severe blood-vessel damage or hemophilia. As one of the basic structural parameters of chitin, the degree of deacetylation (DD) significantly affects the material's physical, chemical, as well as biological properties. In this study, partially deacetylated chitins with a wide range of DD (23–81%) were prepared by homogeneous deacetylation, and sponges with these various chitins were fabricated by freeze-drying to study the effects of DD on their hemostatic properties. Among all sponge samples, the chitosan sponge with a DD of 48% showed the highest water absorption, whole blood adsorption, RBC adsorption rate, and the best hemostatic performance in an uncontrolled bleeding model of the rat femoral artery, demonstrating that a certain proportion of acetyl amino and amino groups could also activate the coagulation system and promote the adhesion of platelet and erythrocyte.

Silver Micro-Nanoparticle-Based Nanoarchitectures: Synthesis Routes, Biomedical Applications, and Mechanisms of Action.

Silver has become a potent agent that can be effectively applied in nanostructured nanomaterials with various shapes and sizes against antibacterial applications. Silver nanoparticle (Ag NP) based-antimicrobial agents play a major role in different applications, including biomedical applications, as surface treatment and coatings, in chemical and food industries, and for agricultural productivity. Due to advancements in nanoscience and nanotechnology, different methods have been used to prepare Ag NPs with sizes and shapes reducing toxicity for antibacterial applications. Studies have shown that Ag NPs are largely dependent on basic structural parameters, such as size, shape, and chemical composition, which play a significant role in preparing the appropriate formulation for the desired applications. Therefore, this review focuses on the important parameters that affect the surface interaction/state of Ag NPs and their influence on antimicrobial activities, which are essential for designing future applications. The mode of action of Ag NPs as antibacterial agents will also be discussed.

Radiation synthesis and characterization of xanthan gum hydrogels

In this study, xanthan gum (XG) based hydrogels were prepared at a paste like state, in the presence of acetylene gas and CCl4 through γ-irradiation. Sodium polyacrylate/XG semi-interpenetrating networks [P(AAcNa)/XG semi-IPNs] were also prepared and characterized. It was determined that XG could not undergo high gelation when irradiated at a paste like state. Relatively higher gelation was obtained in the presence of CCl4. Irradiations carried out in the presence of acetylene resulted in formation of insoluble structures and viscosity of XG increased almost threefold up to a certain dose. Hydrogel structures with superabsorbent character and highest gelation were obtained with P(AAcNa)/XGsemi-IPNs. Swelling and absorbency under load (AUL)tests showed that P(AAcNa)/XG semi-IPNs have as much fluid absorption capacity as commercially available super absorbent polymers (SAPs). Basic network structural parameters of the P(AAcNa)/XG semi-IPNs were also calculated and characterized by mechanical and rheological tests. It was determined that the addition of XG to the P(AAcNa) structure greatly enhanced the mechanical strength of the hydrogels while fluid absorption capacities were adequately high for a novel XG based superabsorbent hydrogel.

Methodologies of heat calculation and selection of rational parameters of regenerative burners operation

Decrease of energy intensity of products is an actual task for all the industries, including steel industry. One of the best solutions to increase energy efficiency of heating facilities is application of recuperative and regenerative burners, which ensure high temperature of air heating. Such high temperatures cannot be achieved at application of heating systems based on central recuperator. It was shown that many countries accomplish studies to perfect recuperative burners and simulation of their thermal operation. However at present there are no universally recognized methodologies of calculation and designing of such equipment. Results of studies presented, which were implemented in three methodologies intended for heat calculation and selection of rational parameters of regenerative burners operation. The methodologies enable also to determine a fuel utilization coefficient for a furnace system based on regenerative burners, to estimate competitiveness of solutions at creation new and modernization existing furnaces comparing with utilization of modern central recuperators. Comparative simplicity of the mathematical apparatus used in the methodologies highlighted, as well as correspondence of the used calculated expressions to the physical nature of the processes taking place. Besides, the methodologies enable during calculation to set the values of important characteristics, which can be reached based on determination of values of basic structure parameters of lining. A scheme of joint application of the elaborated methodologies proposed.

High-sensitive gas-mixture detection based on Mie resonance in slotted MDM metasurface

A high-sensitive gas sensor structure based on Mie resonance in a slotted MDM metasurface is proposed. The sensing performance of slotted and original gold-ring MDM structures is comprehensively compared under the same basic structural parameters. The slotted part can be coated with a gas-sensitive film to construct a new MDM structure in the x-direction, improving the sensitivity effectively with optimized parameters. The detection of mixed gases will not be disturbed. The sensitivity of methane and hydrogen are − 4.516 nm / % and − 1.051 nm / %. The relationship between the polarization angle of the incident light and extinction spectrum is also established to provide feasibility for detecting the polarization angle.

A tunable ultra-wideband cross-polarization conversion based on the band splicing technology

A novel tunable terahertz metamaterials polarization converter (PC) is presented in this paper, whose operating band can be extended by the innovative band splicing technology (combine different PCs with different bands to make the bands splice together) and adjusted into a broadband absorber via adjusting the temperature. Four different units are combined to form a supercell and the phases can be matched through the phase compensation optimization technology. It is a noteworthy finding that the working band becomes wider significantly as the four different working bands join together by the band splicing technology. At the same time, under the action of vanadium dioxide (VO2), the amplitude of reflectance is regulated through the temperature field. The simulation results display that below the critical temperature of 341 K (68 °C), VO2 is treated as an insulator (σ = 20 S/m), the cross-polarization conversion (CPC) can be achieved in the frequency range of 0.91–1.67 THz, whose relative bandwidth (RB) reaches 58.9%. The operating band is expanded compared with four single small units with similar basic structure but different parameters, whose bands are 1.11–1.714 THz, 1.08–1.68 THz, 1.13–1.7 THz, and 1.024–1.608 THz with polarization conversion ratios (PCRs) above 0.9. At high temperature which exceeds the critical temperature, VO2 turns into metal (σ = 200,000 S/m) and the PC is switched into an ultra-broadband absorber with the operating band of 0.744–1.782 THz (the relative bandwidth (RB) of 82.1%), which is significantly different from that at low temperature. Without complex geometry, the reflected PC can broaden the bandwidth on the existing basis. Besides, this metamaterial structure builds a bridge between the polarization converter and the absorber by taking advantage of the non-contact control method, which strengthens the degree of freedom of the electromagnetic metamaterials that would further create a greatly fertile ground for their applications.

Synthesis and characterization of low-cost zeolite NaA from coal gangue by hydrothermal method

Through this investigation, we have demonstrated a low-cost preparation method of zeolite NaA from coal gangue. The well-developed zeolite NaA of 87.56% crystallinity was successfully prepared by hydrothermal alkali activation method, which required low alkali concentration (1.8 mol/L) compared to other researches (3–6 mol/L). The characterization results of product prepared at different conditions suggest that the purity and crystallinity of zeolite NaA are high at low alkali concentration and longer crystallization time. The Ca2+ exchange value of synthesized zeolite attained 265 mg CaCO3/g compared to commercial zeolite, which is typically 340 mg CaCO3/g. The basic structure parameters and thermal stability have also been studied. The results suggest that the obtained zeolite has a potential to be used as hard water softening agent. Moreover, the result of Rietveld quantitative phase analysis and Box-Behnken's response surface methodology showed that the weight fraction of zeolite NaA in product can reach 71.9%, and the crystallinity can attain 88.14% at the optimal condition of n(SiO2)/n(Al2O3) of 2.60, NaOH(aq) concentration of 1.86 mol/L at 95 °C for 10.08 h.

Magnesium Oxychloride Cement Composites with MWCNT for the Construction Applications.

In this contribution, composite materials based on magnesium oxychloride cement (MOC) with multi-walled carbon nanotubes (MWCNTs) used as an additive were prepared and characterized. The prepared composites contained 0.5 and 1 wt.% of MWCNTs, and these samples were compared with the pure MOC Phase 5 reference. The composites were characterized using a broad spectrum of analytical methods to determine the phase and chemical composition, morphology, and thermal behavior. In addition, the basic structural parameters, pore size distribution, mechanical strength, stiffness, and hygrothermal performance of the composites, aged 14 days, were also the subject of investigation. The MWCNT-doped composites showed high compactness, increased mechanical resistance, stiffness, and water resistance, which is crucial for their application in the construction industry and their future use in the design and development of alternative building products.

Simulation of energy evolution during deformation failure process of the layer-intact structure

To research the failure mechanism of the layer-crack structure of surrounding rock in deep mine roadway, the combination (Layer-Intact structure) of shallow layer-crack coal and deep complete coal was taken as the research object, and the mechanical behavior and energy evolution law of the Layer-Intact structure under uniaxial and biaxial compression were studied by numerical simulation with particle flow code (PFC2D). The results show that: (1) In the Layer-Intact structure, layer-crack specimen is destroyed prior to intact specimen; The degree of fragmentation increases with the increase of confining stress, and decreases with the increase of fissure number; (2) The confining stress and the fissure number have a significant impact on the basic mechanical parameters of the Layer-Intact structure. The peak stress of the structure increases first and then decreases with the increase in the confining stress, and decreases with the increase in the fissure number; (3) When fissure number is constant, the energy ratio of layer-crack specimen (strain energy stored in the layer-crack specimen to the the whole specimen) increases first and then decreases with the increase in confining stress, while the energy ratio of intact specimen (strain energy stored in the intact specimen to the whole specimen) decreases first and then increases. When the confining stress is constant, with the increase in the fissure number, energy storage capacity of the Layer-Intact structure is reduced, the energy ratio of layer-crack specimen decreases, while the energy ratio of intact specimen increases. The research can provide some reference for revealing the energy release for dynamic instability of layer-crack structure.

DFT-Based Calculations of the Structural Stability, Electronic and Elastic Characteristics of BBi1-xSbx Ternary Ordered Alloys

The structural, phase stability, elastic and electronic properties of Sb-doped BBi have been systematically investigated in the zinc blende phase by means of the first-principle approach based on the density functional theory (DFT). The structural and elastic properties were computed by using the generalized gradient approximation proposed by Wu and Cohen (WC-GGA). Specifically, the calculated basic structural parameters, such as the lattice constant and bulk modulus, are in good agreement with the existing experimental measurements and theoretical calculations. The phase stability of BBi1-xSbx alloys in the zinc blende and rock salt phases has been investigated with the determination of the transition pressures (Pt) from the zinc blende (B3) to the rock salt (B1) phase. The electronic band structures were determined using the Tran–Blaha-modified Johnson functional. Furthermore, we investigated the mechanical properties and anisotropic behavior of the BBi1-xSbx alloys.

Preliminary insulation design for transmission line of CFETR NNBI test platform

Abstract In order to satisfy the requirements of China Fusion Engineering Test Reactor (CFETR) for neutral beam injector system, a Negative-ion Based Neutral Beam Injector system (NNBI) test platform will be established by Institute of Plasma Physics Chinese Academy of Sciences (ASIPP). The high voltage Transmission Line (TL) plays an important role in the NNBI system, connecting the ion source and the power supply system. The TL will be insulated by gas insulation technology, that is, Gas Insulated Transmission Line (GITL). This paper mainly focuses on the insulation dimension design of TL2, which is the longest and main section of the TL. Firstly, the method of determining the design criteria of TL2 gas insulation is given, the gap required by gas insulation is analyzed and the condition of electric field strength to prevent the movement of conductive particles is put forward; secondly, the basic design principles of TL2 insulation design are put forward and the design method of wall thickness of TL2 central conductor and grounding shell is given. Finally, according to the above insulation requirements and design methods, some basic structural parameters of TL2 of the NNBI test platform are determined, including the outer radius and wall thickness of the central conductor and the inner radius and wall thickness of the grounding shell. The outer radius and the wall thickness of the intermediate voltage (rated as −200 kV) conductor are selected as 50 mm and 5 mm, the outer radius and the wall thickness of the high voltage (rated as −400 kV) conductor are selected as 250 mm and 5 mm, while the inner radius and the wall thickness of the grounding shell with tolerated gas pressure from 0.45 MPa to 0.6 MPa, are selected as 525 mm and 10 mm, which lays a foundation for the subsequent detailed design of TL.

Structure optimization of an ultrahigh frequency radio frequency identification tag thread based on the normal mode helix dipole antenna

This paper describes the design of a novel ultrahigh frequency radio frequency identification (UHF RFID) tag thread that mainly consisted of the common yarn and the normal mode helix dipole antenna. The linear dipole antenna for the UHF RFID tag thread was too long to miniaturize the tag. In order to maximize the read performance and miniaturize the size of the tag, the basic antenna structure parameters, such as the helical pitch and single arm length, were optimized by analyzing the radiation parameter S11 of the normal mode helix dipole antenna based on simulation experiments. The simulation experiments started with optimizing the single arm length to obtain the minimum of the S11 parameter at resonant frequency, then the helical pitch was further optimized to limit the resonant frequency to the UHF range. The simulation results showed the resonant frequency rises with an increase of helical pitch and declines with an increase of single arm length. Furthermore, a series of UHF RFID tag threads with good performance from the simulation cases were prepared, and the performance of the optimized tag was validated. Generally, the UHF RFID tag thread with optimized helix dipole antenna could reduce the axial length of the tag by 57% and improve the reading range by 500%, and its performance was greatly superior to that of the UHF RFID tag thread with the classical linear dipole antenna.

Abstract 215: Negative Regulation of Adherens Junction Formation Patterns Cellular Parameters Required for Cardiac Pacemaking

Cardiac Pacemaker Cells (CPCs) rhythmically initiate the electrical impulses that drive heart contractions. Paradoxically, CPCs display the highest rate of spontaneous depolarization in the heart despite being subjected to unfavorable electrochemical conditions that should theoretically suppress their activity. How CPCs overcome such barriers remains a fundamentally unresolved topic in our understanding of cardiac electrophysiology. To address this, we have used computational modeling, high resolution in vivo imaging, and direct genetic manipulation of CPCs to examined the developmental processes that coordinate CPC electrical integration into the embryonic heart. Through these studies we have uncovered a series of previously unrecognized cytoarchitectural patterning events that are critical for CPC function. Specifically, we have identified that CPCs uniquely internalize their adherens junction complexes during early cardiac morphogenesis. As a result, CPCs adopt physical attributes, such as small cell size, and electrical characteristics, including poor gap junctional coupling, that are highly beneficial for maintenance of their excitability. Importantly, our data also demonstrate that ectopic adherens junction formation severely perturbs CPC function in a force dependent manner. Thus, these data highlight that regulation of cell-cell interactions controls the basic structural parameters needed to support CPC activity in the heart and that local cellular mechanics should be a design consideration as cellular-based therapeutics for the correction of CPC dysfunction become increasingly feasible.

Anion replacement effect on BaCd2X2 (X = P, As, Sb, Bi) compounds: A first principles study

Cadmium based Zintl phase compounds have been recently studied for the thermoelectric applications. Many interesting experimental results reported on the 1-2-2 cadmium based compounds, however less attention been paid to study them though first principles methods. In the current work, BaCd2X2 (X= P, As, As, Bi) compounds have been studied comprehensively for the basic structural parameters, electronic band profiles, optical characteristics and thermoelectric properties. Poirier–Tarantola equation of state is used to fit the volume and energy data. The calculated results are consistent with the reported experimental results. Electronic band profiles of the compounds reveal that the compounds are semiconductors except BaCd2Bi2 which is metallic. Valence band is composed on mainly X-p states while Ba-d state in conduction band. Compounds show prominent absorption in the visible region with extension to low frequency ultraviolet region. The characteristics optical peaks redshifted by anion replacement from P to Bi. Thermoelectric properties of the compounds are also studied for possible thermoelectric applications.

Germanate glasses containing lead and bismuth oxides: Correlation between elastic and compositional parameters

Elastic properties of germanate GeO2–PbO and GeO2–PbO–Bi2O3 glasses have been interpreted and predicted in order to explore the structural role of PbO and Bi2O3 in the germanate network. To establish the applicability of Makishima-Mackenzie's theory and Rocherulle et al. model for these glasses, the theoretical elastic moduli and Poisson's ratio were evaluated and compared with the experimental ones. The basic compositional and structural parameters were calculated and correlated with elastic properties. PbO changes the continuous germanate network to the continuous lead–germanate network by formation of PbO4 and GeO6 units, in addition to GeO4 units. Whereas Bi3+ ions occupy interstitial positions in GeO2–PbO–Bi2O3 glasses by formation of deformed BiO6 octahedral units. Both Makishima-Mackenzie's theory and Rocherulle et al. model are valid for majority of samples. The divergence between theoretical and experimental data was attributed to the anomalous behavior between the calculated dissociation energy per unit volume and elastic moduli.

Evaluation of D2D Communications in 5G Networks

5G networks are being tested today. 5G networks are capable of improving existing services and delivering new quality of service through low latency, such as tactile internet. Existing technologies do not meet the requirements of 5G, which necessitates the development of new technologies. These include new connectivity methods that depend on the quality of the network's functioning. One of the most famous D2D communications. 5G networks use millimeter-band technologies. As the radio signal energy of the millimeter range is strongly absorbed by the environment, this range has a short communication range, so a large number of base stations must be installed in the network. But this is not always effective as their use decreases. D2D device-to-device technology is used to solve this problem. In order to ensure a high quality of network service, attention must be paid to the structure of the D2D organization. The basic structural parameters are the communication distance, the communication radius and the number of repeaters. This can be solved by selecting the relay node correctly. For this purpose it is necessary to take into account the change of the allowed data rate in the channel due to the allocation of its resources by the network node, used as a repeater. In order for the route to provide the necessary bandwidth, it is necessary to change the distance between the network nodes. This ensures network connectivity and the required level of quality of service. This is achieved by choosing the optimal algorithm that is considered in the article.

Recognition of the layout of colored yarns in yarn-dyed fabrics

The layout of colored yarns in yarn-dyed fabrics is a significant part of designing and production in the textile industry, which is still analyzed manually at present. Existing methods based on image processing have some limitations in accuracy and stability. Therefore, an automatic method is proposed to recognize the layout of colored yarns and some other basic fabric structure parameters: the fabric density and weave pattern. First, a large dataset with fabric structure parameters is constructed. The fabric images are captured by a wireless portable device. Then the yarns and floats are accurately located using a novel multi-task and multi-scale convolutional neural network. Finally, a density-based color clustering algorithm is proposed to recognize the layout of colored yarns. The results of extensive experiments show that the proposed method can automatically identify the basic structure parameters with high effectiveness and robustness.

Principles of Building Systems with Concentrated Solar Energy

Design methods and mathematical models for calculating the characteristics of solar module concentrators with specified optical energy parameters have been developed and investigated. These parameters increase the efficiency of solar power plants operating both in a stationary mode and with a tracking system. Modules with parabolic concentrators, linear and cylindrical photodetectors were used in stationary and solar-tracking arrays. The basic structural and functional parameters of solar modules, the concentration and distribution of concentrated solar radiation over the focal spot width depending on the parametric angle based on the lower and upper parabolas were calculated using physical and mathematical models and derived universal analytical expressions. The given characteristics show possible variants of the dependence of the geometric concentration on the parametric angle of the concentrator for different values of the parameters of the universal analytical equation. The dependences of the geometric concentration on the parametric angle of parabolic concentrators are calculated for different values of the structural parameters: the profile of the module of two conjugate compound concentrators; the concentration distribution along the receiver from the upper and lower concentrators and the module as a whole; and the distribution of illumination along the lateral surface of a cylindrical solar radiation receiver. It is shown that the ratio of the experimental concentrations to the calculated characteristics agrees with the optical efficiency of the modules. The above calculation methods based on the principles of constructing systems with concentrated solar energy allow a comparative analysis of the parameters and the choice of the design of various types of concentrators for the solar modules being developed.