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Highlights • Study into size reduction of sulfones based on the use of ultrasound. • Ultrasound established as an effective approach for size reduction. • Mean size and D90 reduced to almost one-third original value due to ultrasound. • The crystalline structure of the product was not disturbed due to ultrasound. Abstract The present study investigates the use of ultrasound in size reduction based on recrystallization of a commercially important compound, 3,3′-diaminodiphenyl sulfone, popularly known as DADPS. Typically the applications of DADPS depends on the size distribution, more importantly on the mean size and hence the ultrasound assisted recrystallization has been applied for controlling the size as an alternative to energy intensive mechanical size reduction. For the size reduction studies, DADPS was dissolved in methanol and irradiated with ultrasound during the anti-solvent crystallization operation using water. Effect of different operating parameters such as temperature, rate of addition of antisolvent and its nature (whether neutral, acidic or basic) and ultrasonic parameters such as time of irradiation, power dissipation and duty cycle on the mean size and overall distribution has been studied. The particle characteristics of the original sample and processed samples have been analyzed using particle size analyzer, optical microscopy and X-Ray Diffraction (XRD). The positive effect of ultrasound for size reduction was clearly established from particle size analysis with reduction in the mean size to almost one-third the initial value under optimum conditions of 100 W as the power dissipation, 70% as the duty cycle and 60 min as the time of operation. In terms of the trends of the operating parameters, an increase in the rate of addition of antisolvent yielded the best results in terms of lower size and also alkaline conditions for antisolvent gave better size reduction. The microscopic images revealed a uniform and well-defined crystal shape on processing using ultrasound while XRD analysis established that ultrasound did not alter the crystalline structure. Ultrasound was overall established as an effective approach for size reduction without any changes in the crystalline structure. [ABSTRACT FROM AUTHOR]

Abstract Grain size distributions (GSD) of pyroclastic materials are the product of processes ranging from primary fragmentation efficiency to tephra transport. As such, a detailed description of their physical and chemical state can provide pivotal information regarding such processes. By constraining the GSD of volcanic deposits one can thereby deliver powerful constraints on the energetics and dynamics of eruptions. In order to do so we must distinguish between two primary controls: 1) fragmentation of magma to tephra, and 2) secondary transport-related processes (such as abrasion and comminution), within the conduit and until deposition of the particles. Variations in particle interactions in the conduit together with conduit geometry, may be major factors in modifying the GSD. As in all physicochemical processes, for eruptive dynamics an experimental basis is an essential element of calibration and quantification. Here, we have conducted the first experimental investigation linking fragmentation and ash production via the influence of 1) particle-componentry and particle-size, and 2) the conduit geometry (constricted versus unconstricted) on the GSD. Rapid decompression experiments with loose tephra material from the fall deposit of Pomici Principali eruption (10.3 ka, Campi Flegrei) have been conducted in an optically transparent setup that enables the optical monitoring of particle dynamics with a high-speed camera. The samples employed can be classified into two main groups; 1) pumices, and 2) dense clasts (including crystals, lava clasts and wall rock fragments). Our results indicate that 1) a conduit diameter constriction (simulating obstacles in the conduit walls) is likely to reduce the average diameter of individual clasts and increase the generation of ash (<63 μm, fine ash); 2) the presence of larger pumice particles in the starting sample results in more efficient ash production; 3) the presence of dense particles is linked to a higher efficiency of size-reduction processes (whereby the presence of crystal-rich pumice appears to have a counterproductive effect). These findings correlate well with existing studies, enabling a general assessment of possible secondary size-reduction processes controlling the GSD of a volcanic deposit. Further, our results also suggest that secondary-generated ash should be considered for hazard assessment and modeling, since increased amounts of ash may affect, e.g., the plume dispersion dynamics, and in turn the area affected by ash deposition. Highlights • Decompression experiments allowed to estimate intra-conduit ash formation processes. • Dense particles can potentially boost a more efficient secondary ash production. • Surface area values increase with amount of dense clasts (entrained) in the mixture. • Crystal-rich pumices might hinder secondary size-reduction processes. • Constrictions within conduit reduces average sizes and enhance production of ash. [ABSTRACT FROM AUTHOR]

A double‐layered DGS transmission line is proposed with a smaller DGS size and less radiation loss. Changing the air boundary to a dielectric boundary reduces the effective electric length at the DGS aperture area. An equivalent circuit model is introduced to analyze the DGS transmission line and the resonator circuit designs. Due to the increase in the effective dielectric constant, the proposed structure can be realized with less sensitivity to metallic environments. From the experimental results, the proposed double‐layered DGS can achieve a reduction of 90.1% in size and insensitivity at up to 5 mm of separation from the DGS aperture to the metallic plate. [ABSTRACT FROM AUTHOR]

Summary: High‐energy ball milling is performed on Li1.1Mn1.95Fe0.05O4 spinel material, synthesized by sol‐gel method for lithium rechargeable battery, at different durations to obtain nanopowders of finite size distributions. The powders are investigated by means of scanning electron microscopy, particle size distribution, and X‐ray diffraction (XRD) measurements. The structural analysis of the powders is performed to investigate the effect of milling on the particle size, crystallite size, and lattice strain. The scanning electron micrographs and size distribution measurements show that the particle size decreases with the increase in milling duration. The XRD results show that the widths of the diffraction peaks increase with the decrease of particle size (increase of milling duration). This broadening is analyzed according to Scherrer, Williamson‐Hall, and Halder‐Wagner methods. Peak broadening is attributed to contributions of crystallite size and lattice strain. While reducing the particle and crystallite sizes is desirable to achieve higher specific capacity and energy density of the battery active material, lattice strain leads to material degradation and a reduced capacity retention. Thus, when performing mechanical milling, lattice strain should be taken seriously into consideration to optimize the milling parameters and to enhance the materials electrochemical performance. [ABSTRACT FROM AUTHOR]

Abstract Significant influence of anoxic events on faunal turnovers in marine communities is well-established. However, many studies are focused on the impact of anoxic conditions on benthic organisms, while coeval changes in pelagic cephalopod assemblages remain relatively poorly understood. In the present paper we discuss the trends in cephalopod assemblages coinciding with the onset of the early Aptian black shale deposition in European Russia coeval with OAE1a. In few sections of the Saratov Volga area (central part of the Russian Platform), representing both offshore and more proximal nearshore lithofacies of the epicontinental Middle Russian Sea, we have recognized simultaneous changes in ammonite and belemnite successions. Belemnites, represented by the late members of the family Oxyteuthididae, are common in the interval directly preceding anoxic event, but totally disappear with the onset of the black shale deposition. For the Deshayesites ammonites shell size reduction across the mudstone – black shale boundary (maximum shell diameter of adults reduces from ∼20 cm to 7–8 cm) can be observed. Some other ammonites become numerous (Sinzovia) within the black shale interval or show a first occurrence in it (Koeneniceras and Volgoceratoides). In our opinion diminishing of Deshayesites shell size during the early Aptian OAE could be caused by coupling of palaeoenvironmental factors such as progressive warming and regional input of brackish water. Preliminary results of carbon isotope studies of aragonite deriving from the ammonite nacreous layer are also provided. [ABSTRACT FROM AUTHOR]

In this paper, we propose a method for designing a dual-channel balanced filter and a dual-channel balun filter based on the quad-mode dielectric resonator (DR) for the first time. By sharing one common quad-mode DR, two balanced filters or two balun filters are integrated as one single-cavity configuration, featuring compact size and high integration. A cylindrical DR with two short ends is investigated to construct the quad-mode DR. By properly arranging input and output feeding probes, two modes of the DR are only excited by the feeding probes of one channel and the other two modes are excited by that of the other channel. Accordingly, signals cannot be transmitted between the two channels, resulting in high isolation. Moreover, the required out-of-phase characteristics of the balanced and balun filters can be obtained by the inherent electromagnetic field properties of the DR without adding additional circuits, featuring a simple structure. For demonstration, a dual-channel balanced filter and a dual-channel balun filter are designed and fabricated, showing excellent balanced or balun filter performance of each channel as well as high isolation between the two channels. As compared to the other reported DR balanced and balun filters, the proposed designs exhibit a significant size reduction, which are attractive in wireless systems. [ABSTRACT FROM AUTHOR]

Abstract Nutritionally, particle size has significant impact on food digestibility in the gastrointestinal system. Controlling the rheological behaviors of particles in dispersion has been of major interest in the industry. In this work, the quinoa seed was ground into flour, followed by fractionating into a selected particle size [+30-mesh (>595-μm) to +200-mesh (>74-μm)]. The effect of particle size on composition, antioxidant, and several functional and mechanical properties of all particle fractions were studied. The protein, crude fat, crude fiber, dietary fiber contents increased with decreasing the particle size while the starch content decreased. The water holding capacity and sediment volume fraction increased with the reduction of particles. Rheological measurement indicated that there were significant differences among rheograms between coarser and finer particles of QF. The finest particles produced a lower complex viscosity and lower mechanical rigidity. The final and setback viscosities decreased as particle size decreased. Microscopy showed irregular-shaped polygon structure for the QF. The particle fractions ranged between +100 and +200-mesh showed compositional resemblances and, subsequently, the properties. The highest extractability of phenolics and antioxidant properties were observed for the finest particles. The information generated from this work would help the industry to develop products with the desired particle size with optimum functional and nutritional properties. Graphical abstract Unlabelled Image Highlights • Quinoa flours fractionated according to their particle size. • A significant difference in composition was observed among particles. • Finer particles exhibited a lower mechanical rigidity and high antioxidant property • Quinoa particles are irregular polygon. • Blending of particle fraction could produce a desired consistency. [ABSTRACT FROM AUTHOR]

In this communication, compact dual-bandgap two via double-slot-type electromagnetic bandgap (TVDS-EBG) structure is presented. The analysis of the TVDS-EBG structure is done by using the $LC$ model. Two resonance parallel $LC$ circuits per unit cell result dual-bandgap in the $x$ - and $y$ -directions. Compactness is achieved because of two via per unit cell, square slot, and inverse C-type slot on an EBG patch. The simulation of the unit cell TVDS-EBG is carried out using an eigenmode solution of Ansys high-frequency structure simulator. Simulated results are validated by experimental results. Simulated and experimental results prove that compared with a two-layer edge located via interdigital-EBG, edge located via-EBG, and Minkowski EBG, TVDS-EBG gives size reduction of 20.48%, 29.03%, and 31.25%, respectively, with a simple structure. The application of the proposed dual-bandgap TVDS-EBG for ultrawideband monopole antenna is also demonstrated. Simulated and measured results show that dual-band-notched can be obtained by using a unit cell of TVDS-EBG at fed line of an elliptical monopole antenna. [ABSTRACT FROM AUTHOR]

Introduction: Thyroid nodules (TNs) are extremely common and most of them are benign in nature. Cryoablation is used in a variety of clinical applications, and has been applied in focal treatment as a substitute or an adjunct to surgery and other nonoperative modalities. Objectives: The objective is to evaluate the effect of cryoablation on the size and function of TN. Subjects and Methods: This was an interventional therapeutic study, conducted at endocrinology clinic, Ain Shams University Hospitals. Our study sample included 80 participants, aged between 20 and 60 years, having TN diagnosed by ultrasound (US). The participants were divided into two groups: Group 1 (control group) included 40 participants who were not subjected to cryoablation and Group 2 (cases) included 40 participants upon which cryoablation was done. Neck US was done for participants and they were sampled for their thyroid-stimulating hormone (TSH), free triiodothyronine (FT3) and free tetraiodothyronine (FT4) levels at start and after 3 and 6 months. Results: There was a high statistically significant difference between Group 1 and Group 2 regarding nodule size after 6 months (0.87 ± 0.25 cm vs. 0.67 ± 0.21 cm, respectively, P < 0.001), in spite of non-significant difference between both groups at the start of study (0.79 ± 0.29 cm vs. 0.83 ± 0.29 cm, respectively, P = 0.619). The median percentage of change in nodule size from 0 to month 6 in control group was +12.50% (IQR: 0%–22.5%), while in cases was −25.0% (IQR: −50%–−4.17%), P < 0.001. Regarding thyroid function tests, there was no statistically significant difference between both groups all through our study. Conclusions: Cryoablation causes nodule size reduction, while it does not affect thyroid function tests. [ABSTRACT FROM AUTHOR]

Testing water meters is essential for efficient management of water resources, and compliance with regulations, water utilities should have a regular testing schedule to ensure that they are providing accurate readings. This highlights the importance of creating and installing water meter test benches that enable accurate calibration for laboratories, industries, and water meter manufacturers. The diverter is an essential part of a flow meter calibration system, and its compliance with standards, is crucial. These standards emphasize the need for quick diversion of flow without changing the flow-rate during the measuring interval. To accomplish this, complex, expensive and large flow diverters are typically utilized, which incorporate a manifold that homogenizes the liquid and produces a sheet of water at atmospheric pressure. This work presents a new diverter switch valve that fulfils with the technical characteristics of a flow diverter established in the international standards, it does not require any nozzle or fishtail transition and it works without long atmospheric liquid sheet. The experiments carried out with different diversion systems compare the results using a conventional design and the new valve. Good repeatability and acceptable uncertainty are obtained using both systems. Hence, this innovative diverter valve presents an opportunity to minimize the size and lower the costs of facilities, thereby enabling a reevaluation of the design, installation, and commissioning of laboratories dedicated to flow meter calibration. • This novel valve offers the possibility of minimizing the size of the facilities. • The valve does not require nozzle or fishtail transition and works under pressure. • Two diverting systems were compared in the same experimental facility. • The valve fulfils the international standards for a flow diverter. [ABSTRACT FROM AUTHOR]

Laser fragmentation of colloidal submicron-sized bismuth ferrite particles was performed by irradiating a liquid jet to synthesize bismuth ferrite nanoparticles. This treatment achieved a size reduction from 450 nm to below 10 nm. A circular and an elliptical fluid jet were compared to control the energy distribution within the fluid jet and thereby the product size distribution and educt decomposition. The resulting colloids were analysed via UV-VIS, XRD and TEM. All methods were used to gain information on size distribution, material morphology and composition. It was found that using an elliptical liquid jet during the laser fragmentation leads to a slightly smaller and narrower size distribution of the resulting product compared to the circular jet.

A new class of back-to-back integrated aperture- and gap-coupled discontinuities is proposed for substrate-integrated waveguide band-pass filter design. The developed structure is shown to take advantage of both discontinuities in the design of cavity and/or planar resonators with an optimum performance including higher quality factor accompanied by transmission zero realisation, wider upper stop-band with second harmonic suppression, and a considerable size reduction. The measured unloaded quality factor has been increased by a ratio of 60% in comparison to the conventional gap-coupled structures. [ABSTRACT FROM AUTHOR]

The design method of a compact cross slot broadband or and circularly polarized microstrip patch antenna was presented.A wide cross-shaped slot was embedded on the square patch for size reduction.The substrate was a stacked structure of an FR4 and an air layer.An L-shaped strip was added in the slot and only by changing the feeding point on the strip,circular polarization or broad impedance bandwidth can be obtained.ANSYS HFSS simulation results show that the circular polarization bandwidth（AR≤3 dB）and impedance bandwidth（VSWR≤2） were 1.7% and 5.8%,respectively.The antenna had stable power gain within a broad bandwidth and its peak power gain was 7.8 dB.Meanwhile,52.3% patch area reduction can be achieved.The impedance bandwidth can be improved to 9.4 % by varying the feeding location and adjusting the two resonance frequencies of the antenna.Compared with traditional microstrip patch antennas,the impedance bandwidth was improved 114%.

Graphical abstract Highlights • A population balance model was applied to pharmaceutical extrudate milling. • The model parameters separate effects of material properties and process conditions. • Parameters determined at lab scale can be used for prediction at commercial scale. • The model can be used for milling development, scale-up, and technology transfer. Abstract This study modeled the particle size distribution (PSD) of pharmaceutical extrudates after milling by developing a so-called time-discrete population balance model (PBM). The PBM, which models size reduction as a series of breakage events, was formulated so that the model parameters separate the effect of material properties and milling process conditions. Because of this novel aspect, the PBM should have excellent predictive capability with specific applications in technology transfer and scale-up. To investigate this application, copovidone extrudate produced by the hot-melt extrusion process was milled using a lab-scale continuous impact mill (Fitz Mill). The effect of impeller speed and classification screen size on PSD of the extrudate was investigated. The PBM with parameters obtained by fitting lab-scale PSD data was then applied to model the PSD of the extrudate following milling by a pilot-scale continuous impact mill (Hosokawa mill). The study found that the parameters determined at the lab-scale can be used to model PSDs at the pilot-scale and may be generally applied to similar classification-type impact mills. Since technology transfer and scale-up can be material and time consuming, this approach may offer significant benefits to the pharmaceutical industry for the development of milling processes. [ABSTRACT FROM AUTHOR]

Abstract High energy ball milling (BM) of micro H-Y zeolites was studied at a wide range of speeds, milling duration, and ball sizes. SEM analysis reveals that BM produces three types of species that can be distinguished namely: nanoparticles, flakes/slabs, and un-ground micro-sized particles. BM at high speeds reduces the particle size of zeolite to the nanometer range in a very short duration. However, BM for longer time led to the formation of zeolite flakes. The particle size reduction was achieved at the cost of loss in zeolite crystallinity. Among several combinations of BM processing parameters, BM at 1000 rpm for short duration were found to be the optimum parameters to reduce the zeolite into nanoparticles while retaining considerable crystallinity. Post BM centrifugation was found to be essential in obtaining a homogeneous particle size distribution. The produced nanoparticles had an average diameter of 50–100 nm, surface area of 465 m2/g, and a crystallinity index of 20%. [ABSTRACT FROM AUTHOR]

The purpose of this study was to investigate the effect of working volume in the high-energy ball-milling process on the breakage characteristics (i.e., particle size, morphology, and chemical composition) and adsorption performance of rice straw ash. This study was conducted to confirm working volume issue since this parameter has correlations with the scaling-up process, the amount of input/output in the ball-milling process, and the breakage characteristics of the material. Rice straw ash was selected as a model of size-destructed material because this material is porous and chemically and thermally inert; thus, the evaluation can be effectively done without any chemical reaction and time-consuming process. To obtain the outcome precisely, the study varied working volume under constant other processing parameters (i.e., ball-to-rice straw ash, milling speed/rotation, temperature, ball size) in the batch-typed conventional ball-milling process. The results showed that the ball-milling process is effective to reduce particle sizes to several micrometers and further nanometers. Precise control of the final particle size was achieved by the adjustment of working volume, in which the less working volume results in the generation of smaller particles. The prospect control of final particle size is due to the control of shear stress and collision phenomena during the ball-milling process. The evaluation was also completed with theoretical approximation and adsorption performance of the product. In addition to varying working volume, this study examined the product yield since it can be a contributive factor to determine the optimum condition of the ball-milling process. [ABSTRACT FROM AUTHOR]

A compact filtering Wilkinson power divider with harmonic suppression based on lumped components is presented in this paper. The new divider uses two 5th-order elliptic-function low-pass filters to replace the quarter wavelength microstrip lines of the conventional Wilkinson power divider. The structure combines the power divider and the filter into a complete device. By integrating elliptic low-pass filters with the power divider, the proposed structure can suppress harmonics due to the filter's band-notched characteristic. The power divider demonstrates a measured suppression of 37.1 dB for the second harmonic, 36.6 dB for the third harmonic, 38.6 dB for the fourth harmonic respectively. The harmonic suppression is higher than 20 dB from 2.75 to 7.035 GHz. Furthermore, lumped components are utilized to achieve improvement on size reduction. Compared with the conventional divider, the proposed structure effectively reduces the size by 77 %. The insertion loss is 3.2 dB at the center frequency (1.45GHz). [ABSTRACT FROM AUTHOR]

The role of rotor impact mill screen plate design in biomass grinding has attracted limited interest. This study aimed to clarify the effect of operational parameters and various screen designs on the fine grinding of Sphagnum moss . Contoured screens having forward (rasp) and backward (inverse rasp) inclined trapezoidal apertures of nominal sizes 0.2, 0.3, 0.4, and 0.5 mm were studied. A smooth screen plate having circular perforations (0.5 mm) was used as a reference. Flow phenomena were modeled with Computational Fluid Dynamics (CFD) using 2D geometry for the screen apertures. Product particle size and capacity were mostly dependent on the equivalent diameter of the screen apertures together with rotor frequency and also on the screen design, while the aspect ratio was solely a function of particle size. Among the screens having nominal sizes of 0.3, 0.4, and 0.5 mm, the smooth screen produced the smallest particle size; followed by the rasp screens and the inverse rasp screens. The smooth screen had higher capacity than the rasp or inverse rasp screens, and a narrower operating range. In the case of 0.2 mm apertures, higher capacity was achieved with the inverse rasp than with the rasp screen. The net energy consumption (SEC) of grinding with the rasp screens was at a lower level than with the inverse rasp screens (or the smooth screen). No difference was seen in the case of the smallest size apertures, however. The results, supported by CFD modeling, indicate that the incidence angle of particles does not explain the passage of particles through screen apertures. The passage is affected by the flow patterns above and within the apertures, and the pressure difference over the screen plate. The eddies within the apertures reduce their effective open area, resulting in product particles much smaller than the aperture size. When the aperture inclination is toward the tangential flow (rasp), an eddy is also generated in front of the aperture that turns the flow perpendicular to the screen surface within the aperture. In contrast, when the aperture inclination is against the tangential flow (inverse rasp), an eddy is generated above the aperture that guides the flow smoothly into the aperture, although the flow has to make a U-turn first. A design of inverse rasps seems to be beneficial when very small apertures are used, as it appears that the eddies formed above the apertures prevent blocking by dislodging accumulated particles. The low SEC with rasp screens does not seem to make the passage of particles through apertures easier, but it does enable more efficient size reduction because of the ability of rasps to serve as a grinding track. [ABSTRACT FROM AUTHOR]

Abstract: A compact quasi‐yagi antenna for multifunction radar applications is proposed, consisting of a dual dipole‐driven element, a half bow‐tie reflector and a bow‐tie director. Size reduction is achieved by adding the half bow‐tie reflector structure. Addition of the half bow‐tie reflector and bow‐tie director improves the gain and front‐to‐back ratio in the Very high frequency (VHF)/Ultra high frequency (UHF) band. The measured −10 dB reflection coefficient bandwidths fully cover the VHF and UHF bands. The measured gain and front‐to‐back ratio (FBR) at 226.5 MHz are 5.63 dBi and 9.39 dB, respectively. The measured gain and FBR at 435 MHz are 5.79 dBi and 9.13 dB, respectively. Therefore, the proposed antenna is suitable for VHF/UHF band multifunction radar applications. [ABSTRACT FROM AUTHOR]

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Abstract: Antenna design is a multifaceted task that involves handling of various performance figures concerning both electrical performance of the structure as well as its geometry. Simultaneous control of several objectives through rigorous optimization is very challenging and virtually impossible through conventional approaches such as parameter sweeping. In this work, we investigate size reduction of ultra‐wideband antenna structures while taking into account the reflection response and total efficiency. Available design trade‐offs concerning the antenna footprint, its wideband matching, and efficiency are identified through numerical optimization. More specifically, the goal is to identify designs that exhibit the minimum possible footprint while maintaining the maximum in‐band reflection and average efficiency within the prescribed thresholds. This is realized by appropriate formulation of the objective function exploiting a penalty function approach. Our methodology is demonstrated using an ultra‐wideband monopole antenna example. As an extension, a 3‐objective Pareto set is further generated using surrogate modeling and multi‐objective evolutionary algorithm. A set of designs generated this way provides a designer with a comprehensive knowledge about the capabilities of a given antenna structure and facilitates a decision‐making process driven by a particular application and performance requirements. [ABSTRACT FROM AUTHOR]

Fine wood powders have advantages over traditional coarse wood particles for various emerging applications. However, an efficient system to produce fine wood powders has not been well established. We investigated the comminution capability and efficiency of a two-stage grinding system consisting of a hammer mill circuit and an rotor impact mill circuit to convert wood feedstocks into fine powders. Air-dried forest harvest residuals were comminuted by the hammer mill circuit to three intermediate product sizes with geometric mean particle sizes of 1618, 669, and 316 µm. These intermediate products were then pulverized into fine wood powders with median particle sizes ranging from 35 to 250 µm. The specific energy consumption increased with the decrease of median particle sizes, with a transition at around 100 µm after which the energy consumption increased exponentially. This large-scale grinding trial provides the reliable energy consumption data for design and process economic analysis of mechanical biomass preprocessing. [ABSTRACT FROM AUTHOR]

Due to its abundance, wood is the pre-eminent lignocellulosic raw material for a sustainable bioeconomy based society. Wood is widely used as fuel, construction material, and raw material in cellulose and lignocellulose based products. Besides the established uses of wood powder, like co-firing with coal and biofuel production, there are also novel uses and process applications, e.g., advanced wood-plastic composites and biochemical production are emerging for which the pulverization or fine grinding of wood is an essential pre-treatment step. Due to the tenacious nature of the wood matrix, size reduction is an energy intensive process and thermal or chemical pre-treatment may be needed to improve economy. This paper provides a broad overview of the fine grinding of wood. First, wood breakage mechanisms and the mechanisms of size reduction are presented, followed by fine grinding techniques and wood pre-treatment methods. A comparison of the specific energy consumption of wood fine grinding in both a gaseous and liquid environment is illustrated. Additionally, examples are given of the role played by pre-treatment methods in decreasing energy consumption. The particle aspect ratio is discussed briefly. Finally, the use and requirements of wood powders in various applications are discussed. [ABSTRACT FROM AUTHOR]

A compact 1.5 GHz microstrip branch-line coupler with harmonic suppression, using low-pass resonators and meandered lines open stubs, is designed and fabricated in this paper. Both significant size reduction and harmonics suppression are achieved in the proposed structure using U-shape low-pass resonators and meandered lines open stubs. The proposed coupler shows more than 24 dB suppression for harmonics (2nd up to 10th). The proposed coupler size has been reduced by almost up to 81% compared to the typical one. The designed coupler is simulated using Advanced Design System software. The measured results verify the simulation data of the designed coupler. [ABSTRACT FROM AUTHOR]

This study investigated whether the effectiveness of pretreatment is limited by a size reduction of Norway spruce wood in biobutanol production. The spruce was milled, chipped, and mashed for hydrogen peroxide-acetic acid (HPAC) and dilute acid (DA) pretreatment. Sugar recoveries from chipped and mashed spruce after enzymatic hydrolysis were higher than from milled spruce, and the recoveries were not correlated with the spruce fiber length. HPAC pretreatment resulted in almost 100% glucose and 88% total reducing sugars recoveries from chipped spruce, which were apparently higher than DA pretreatment, demonstrating greater effectiveness of HPAC pretreatment on sugar production. The butanol and ABE yield from chipped spruce were 126.5 and 201.2 g/kg pretreated spruce, respectively. The yields decreased with decreasing particle size due to biomass loss in the pretreatment. The results suggested that Norway spruce chipped to a 20 mm length is applicable to the production of platform sugars for butanol fermentation. [ABSTRACT FROM AUTHOR]

Lenstra-Lenstra-Lovász (LLL) is an effective receiving algorithm for Multiple-Input-Multiple-Output (MIMO) systems, which is believed can achieve full diversity in MIMO detection of fading channels. However, the LLL algorithm features polynomial complexity and shows poor performance in terms of convergence. The reduction of algorithmic complexity and the acceleration of convergence are key problems in optimizing the LLL algorithm. In this paper, a variant of the LLL algorithm, the Hybrid-Fix-and-Round LLL algorithm, which combines both fix and round measurements in the size reduction procedure, is proposed. By utilizing fix operation, the algorithmic procedure is altered and the size reduction procedure is skipped by the hybrid algorithm with significantly higher probability. As a consequence, the simulation results reveal that the Hybrid-Fix-and-Round-LLL algorithm carries a faster rate of convergence compared to the original LLL algorithm, and its algorithmic complexity is at most one order lower than original LLL algorithm in real field. Comparing to other families of LLL algorithm, Hybrid-Fix-and-Round-LLL algorithm can make a better compromise in performance and algorithmic complexity. [ABSTRACT FROM AUTHOR]

This communication presents a miniaturized printed circuit board (PCB)-based surface plasmon wave antenna with high gain designed using substrate integrated waveguide (SIW) technology. The periodic grooves made on substrate provide constructive superposition of electric field due to surface plasmon resonances which lead to an antenna gain enhancement. Furthermore, using PCB with a high relative permittivity shifts the surface plasmon resonance to lower frequencies and shrinks the antenna size. The antenna is fed from the bottom layer by a feed line which couples the power to patch and surface plasmon waves through a cavity. Then, the power is propagated by the patch and SIW grooves where surface plasmons resonate. The measurement results show that a high gain of 17.4 dBi is achieved along with a narrow beamwidth and a low sidelobe level of 11 dB, approximately. [ABSTRACT FROM PUBLISHER]

This study investigated size reduction of five herbaceous species: wheat straw, corn stover, switchgrass, miscanthus, and canola straw. The biomass samples were air-dried to moisture content of 10%. The instantaneous power input to grind the material was recorded. Grinding wheat straw, corn stover, and canola straw using a 3.2 mm screen inside the hammer mill consumed 32 to 35 kWh/t whereas grinding switchgrass and miscanthus on the same screen used 22 kWh/t of energy. All five biomass samples required almost the same amount of energy input (13 to 20 kWh/t) when a 6.4 mm screen was installed in the hammer mill. Some species like corn stover produced strings of fiber causing blockage of the inlet to the grinder. A linear relation was developed between geometric mean diameter ( d gw ) of the ground particles and the screen size ( SS ). The screen size inside the hammer mill was used as the representative size of the particles. The Rittinger equation was fitted to the size data to estimate the equation constant k R from energy input vs. screen size. The k R value ranged from 96 to 267 J mm/g depending on the species. [ABSTRACT FROM AUTHOR]

Background: Large sequence datasets are difficult to visualize and handle. Additionally, they often do not represent a random subset of the natural diversity, but the result of uncoordinated and convenience sampling. Consequently, they can suffer from redundancy and sampling biases. Results: Here we present Treemmer, a simple tool to evaluate the redundancy of phylogenetic trees and reduce their complexity by eliminating leaves that contribute the least to the tree diversity. Conclusions: Treemmer can reduce the size of datasets with different phylogenetic structures and levels of redundancy while maintaining a sub-sample that is representative of the original diversity. Additionally, it is possible to fine-tune the behavior of Treemmer including any kind of meta-information, making Treemmer particularly useful for empirical studies. [ABSTRACT FROM AUTHOR]

Biofuels derived from cellulosic biomass offer one of the best near- to midterm alternatives to petroleum-based liquid transportation fuels. Biofuel conversion is mainly done through a biochemical pathway in which size reduction, pelleting, pretreatment, enzymatic hydrolysis, and fermentation are main processes. Many studies reveal that biomass particle size dictates the energy consumption in the size reduction. Biomass particle size also influences sugar yield in enzymatic hydrolysis, and biofuel yield in fermentation is approximately proportional to the former enzymatic hydrolysis sugar yield. Most reported studies focus on the effects of biomass particle size on a specific process; as a result, in the current literature, there is no commonly accepted guidance to select the overall optimum particle size in order to minimize the energy consumption and maximize sugar yield. This study presents a comprehensive experimental investigation converting three types of biomass (big bluestem, wheat straw, and corn stover) into fermentable sugars and studies the effects of biomass particle size throughout the multistep bioconversion. Three particle sizes (4 mm, 2 mm, and 1 mm) were produced by knife milling and were pelletized with an ultrasonic pelleting system. Dilute acid method was applied to pretreat biomass before enzymatic hydrolysis. Results suggested 2mm is the optimum particle size to minimize energy consumption in size reduction and pelleting and to maximize sugar yield among the three particle sizes for big bluestem and wheat straw biomass. Nevertheless, there is no significant difference in sugar yield for corn stover for the three particle sizes. [ABSTRACT FROM AUTHOR]

Abstract: A practical miniaturized ultra‐wideband monopole antenna with a five‐section ground plane slit is proposed. The structure is a modification of a reference antenna designed with the two‐section ground plane slit and featuring the footprint area of 216 mm2. To reduce the antenna size, a ground plane modification was introduced in the form of a five‐section slit below the feeding line. Furthermore, all geometry parameters of the structure were simultaneously optimized. The final design exhibits a small size of only 22.5 × 7.9 mm2 with footprint of 178 mm2 and good electrical and field characteristics. Experimental validation and comparisons with recently reported designs are also provided. [ABSTRACT FROM AUTHOR]

In this letter, an improved algorithm for electromagnetic (EM)-driven size reduction of wideband antennas is proposed. Our methodology utilizes variable-fidelity EM simulation models, auxiliary polynomial regression surrogates, as well as multipoint response correction. The constraint handling is implicit, using penalty functions. The core optimization algorithm is a trust-region gradient search with a repair step added in order to facilitate exploration of the feasible region boundary. The latter results in considerable reduction of the computational cost of the optimization process. The proposed methodology is demonstrated using two wideband antennas and compared to both direct optimization of the high-fidelity model and the surrogate-assisted framework without the aforementioned repair step. The results indicate superiority of the presented approach. Experimental validation of the fabricated prototypes of the optimized antennas is also provided. [ABSTRACT FROM AUTHOR]

Pollution is one of the important issues faced by marine resources including zooxanthellae, which is known to be very sensitive to environmental changes. Some pollutants have been reported to have adverse effects on zooxanthellae, however, their sensitivity in regards to changes on cell size of these algae has not been widely explored. This study examined the effects of pollutants on the sensitivity of zooxanthellae through changes in size. Zooxanthellae were isolated from corals Porites lutea, Acropora aspera, and Montipora digitata collected from Panjang Island, Jepara, Indonesia. These algae were exposed to pollutants i.e. heavy metals (Cu, Cd, Pb) and nutrients (ammonium and phosphate) at concentrations of 5,10,15 ppb and 5,10,15 µM, respectively. Zooxanthellae size were measured five hours after pollutants exposure. The results showed that all treatments reduced the size of zooxanthellae. Algae isolated from P. lutea are the least affected by pollutants and the highest percentage cell size reduction was found in phosphate treatment. However, reduction on the size of algae were not statistically significant. These results indicate that in relation to reduction in the size, zooxanthellae are not sensitive to pollutants. [ABSTRACT FROM AUTHOR]

In this paper a new “active output filter” (AOF) for variable speed constant frequency (VSCF) power system in aerospace applications is proposed. The proposed AOF is envisioned as a power semiconductor filter block. In the proposed system the passive L-C output filter components are replaced by an H-bridge. The H-bridge is operated at high frequency to inject voltage harmonics to achieve a sinusoidal output voltage to the load. Advanced wide band gap devices can be employed in the design of AOF block to obtain high performance with simultaneous reduction in size. The proposed AOF concept offers a significant reduction in size/weight compared to passive L-C. Further, in the presence of AOF the main VSCF inverter can be operated in a six-step and/or at a reduced PWM frequency. An example 250 kVA, 3-phase 400-Hz system with the proposed AOF concept is evaluated via simulation with a corresponding passive L-C filter configuration. Experimental results on reduced kVA laboratory prototype are discussed. [ABSTRACT FROM AUTHOR]

This paper presents a new coupler configuration which can be designed with both arbitrary power division and nonstandard phase difference at the output ports. The planar coupler ring is composed of four section microstrip lines and an open stub resulting in ease of fabrication. Its circuit parameters can be easily determined by the derived closed-form equations and the corresponding performance in terms of power division ratio, output phase difference, and the tunable parameters is mainly analyzed. Compared with the previous counterparts, its bandwidth and area have obvious superiority. For experimental verification, two prototypes, operating at 1 GHz, have been designed and implemented in microstrip process. One demonstrates a 45° phase difference with equal outputs and the other is designed for a 105° phase difference with 6.02 dB power division ratio. The design theory has been supported with good agreement between the simulated and measured responses. [ABSTRACT FROM AUTHOR]

This work is aimed at optimizing the dimensions of a semicircular-bladed Savonius Style Wind Turbine (SSWT) using Differential Evolution (DE) based inverse optimization methodology to simultaneously satisfy a given power and torque characteristics. The results obtained from the inverse analysis are well-validated with the experimental wind tunnel results available under different wind speeds. The effect of necessary blockage corrections is considered. Using DE-assisted inverse method, the present study demonstrated smaller turbine dimensions than those reported in various literature and also yields a lower value of the blockage ratio. The overall area of the SSWT is found to be reduced upto 9.8% with respect to the corresponding experimental wind tunnel data. The improvement is attributed due to an optimized interplay between multiple combinations of parameters satisfying a given power and torque. To achieve a given power and torque requirement under a given range of tip speed ratio, it appears from the study that the blade overlap can be significantly regulated through minor adjustments of the chord length and turbine height. The sensitivity analysis reveals that the aspect ratio governing parameters such as turbine height and chord length are critical factors governing the torque and power output from SSWTs. In order to meet a desired power and torque, the present study offers a novel inverse methodology aided by the DE algorithm to simultaneously estimate and optimize geometric parameters of SSWT. The benefit of this work is to provide an alternative and optimized solution to the existing literature data where the overall area of SSWT can be reduced and significant material along with space savings can be accomplished. [ABSTRACT FROM AUTHOR]