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A wideband amplifier up to 50 GHz has been implemented in a 0.25 μm, 200 GHz ft SiGe BiCMOS technology. Die size was 0.7×0.73 mm2. The two-stage design achieves more than 11 dB gain over the whole 20 to 50 GHz band. Gain maximum was 14.2 dB at 47.5 GHz. Noise figure was lower than 9 dB up to 34 GHz and a current of 30 mA was drawn from a 4 V supply. To the author’s best knowledge this is the highest gain bandwidth product of a monolithic SiGe HBT amplifier ever reported.

Nanocrystal suspensions proved to be a potent enabling principle for biopharmaceutics classification system class II drugs with dissolution limited bioavailability. In the example of itraconazole (ITZ) as a model drug combined with electrosteric stabilization using hydroxypropyl cellulose (HPC-SL), sodium dodecyl sulfate (SDS) and polysorbate 80 (PS80), the impacts of formulation and process parameters of a dual centrifugal mill on material attributes such as particle size, zeta potential, particle morphology, storage stability and especially solid-state characteristics were evaluated. A minimal concentration of 0.9% (w/w) HPC-SL, 0.14% (w/w) SDS and 0.07% (w/w) PS80 was necessary for sufficient nanoparticle stabilization. Despite the minor effect of PS80, its presence was beneficial for electrosteric stabilization. Choosing lower stabilizer concentrations resulted in a pronounced increase in particle size due to agglomeration, which was confirmed by SEM imaging and a decrease in zeta potential in combination with an amorphization of the particles. Milling temperature had no significant impact on the particle size, whereas milling speed and the size of the milling beads used were found to have a strong impact on the critical material attributes such as particle size and polydispersity index. The smallest particle sizes could be obtained by using the smallest milling bead size. However, the smallest obtainable particle size could only be achieved by using two-fold stabilizer concentrations, as smaller particles exhibit a larger specific surface area.

The yellow mealworm (Tenebrio molitor L., Coleoptera: Tenebrionidae) is an edible insect and due to its ubiquitous occurrence and the frequency of consumption, a promising candidate for the cultivation and production on an industrial scale. Moreover, it is the first insect to be approved by EFSA 2021 following the Novel Food Regulation. Industrial production of mealworms necessitates optimized processing techniques, where drying as the first postharvest procedure is of utmost importance for the quality of the final product. The focus of the present study was to analyse the chemical composition, antioxidant capacity, volatile compound profile and colouring of mealworm larvae dried in various regimes (freeze-drying, microwave drying, infrared drying, rack-oven drying and high-frequency drying). Proximate composition and fatty acid profile were similar for all dried larvae. Freeze dried larvae were predominantly marked by lipid oxidation with significantly higher peroxide values, secondary/tertiary oxidation products in the headspace GC-MS profiles and lower antioxidant capacity. High-temperature treatment in the rack oven—and to some extent also infrared or microwave drying—led to mealworm larvae darkening and the appearance of volatile Maillard secondary products such as 2-methylpropanoic acid, 2-/3-methylbutanoic acid and alkylpyrazines. High-frequency drying as a new emerging technology in insect processing was the most cost-effective method with energy costs of solely 0.09 Є/kg T. molitor L. leading to final larval material characterized by both lipid oxidation and nonenzymatic Maillard-browning.

The formation of pharmacobezoars from suspensions of spray-dried amorphous solid dispersions (SD-ASDs) of new chemical entities (NCEs) and hydroxypropyl methylcellulose acetate succinate (HPMC-AS) represents a non-compound related adverse effect in preclinical oral toxicity studies in rodents. Whereas the contribution of the insolubility of the carrier polymer to this process taking place in the acidic environment of the rodent stomach is conclusive, unawareness of the extent of in vivo pharmacobezoar formation is adverse. In order to evaluate the risk of pharmacobezoar formation before in vivo administration, we subsequently introduce an in vitro model to assess the agglomeration potential of solid dispersions. To verify that the pharmacobezoar formation potential can be assessed based on the observed agglomeration potential, we conducted a sequence of experiments with two HPMC-AS-based SD-ASD formulations. In vitro, we found their different in vivo pharmacobezoar formation potential reflected by a significantly increased agglomerated mass of formulation 1 per day compared to formulation 2. In order to find an approach to reduce the agglomeration potential of solid dispersion from suspensions, we further applied the model to investigate the impact of the viscosity of the vehicle used to prepare suspensions on agglomerate formation.

This paper presents the analysis and design of a wideband asymmetrical Doherty amplifier. The frequency response of the output combining network of the Doherty amplifier with arbitrary back-off level configuration is analyzed. Other bandwidth-limiting factors were discussed and analyzed as well. A number of performance enhancement techniques were taken into consideration to obtain high and flat back-off efficiency over the amplifier design band of 1.7–2.25 GHz. The designed Doherty amplifier had, at 8.0–9.9 dB output back-off, a minimum efficiency of η = 50% [power-added efficiency of 45%], measured near 40 dBm of output power, and over 28% bandwidth. Using digital predistortion (DPD) linearization, an adjacent-channel leakage ratio (ACLR) of −43 dBc was obtained for a single-carrier W-CDMA signal, at 40.9 dBm and 46% of average output power and drain efficiency, respectively. The designed amplifier represents the first wideband Doherty amplifier reported over extended power back-off range.

In this contribution, a design methodology for octave-bandwidth power amplifiers (PA) for 5G communication systems using surface mount dual-flat-no-lead packaged gallium-nitride high-electron-mobility transistor devices is presented. Systematic source- and load-pull simulations have been used to find the optimum impedances across 75% fractional bandwidth for S- (1.9–4.2 GHz) and C-band (3.8–8.4 GHz) PAs. The harmonic impact is considered to improve the output power and efficiency of the PAs. Utilizing the characteristic behavior of the transistors leads to modified optimum fundamental load impedances for the low-frequency range, which have higher gain compared with high-frequency range, and minimize the influence of the higher harmonics. Continuous wave large-signal measurements of the realized S-Band PA show a power added efficiency (PAE) of more than 40% from 1.9–4.2 GHz and a flat power gain of 11 dB while achieving a saturated output power of 10 W. The measured performance of the C-Band PA demonstrates a delivered power between 3.5 and 5 W across the frequency range of 3.8–8.4 GHz. A flat power gain of around 9 ± 0.5 dB with 26–40% PAE is achieved.

In this paper, design, implementation, and experimental results of efficient, high-power, and multi-octave gallium nitride-high electron mobility transistor power amplifier are presented. To overcome the low optima source/load impedances of a large transistor, various topologies of a broadside-coupled impedance transformer are simulated, implemented, and measured. The used transformer has a flat measured insertion loss of 0.5 dB and a return loss higher than 10 dB over a decade bandwidth (0.4–4 GHz). The transformer is integrated at the drain and gate sides of the transistor using pre-matching networks to transform the complex optima source/load impedances to the appropriate impedances of the transformer plane. The measurement results illustrate a saturated output power ranged between 80 and 115 W with an average drain efficiency of 57% and gain of 10.5 dB across 0.6–2.6 GHz.

The present paper presents a fully differential 60 GHz four stages low-noise amplifier for wireless applications. The amplifier has been optimized for low-noise, high-gain, and low-power consumption, and implemented in a 90 nm low-power CMOS technology. Matching and common-mode rejection networks have been realized using shielded coplanar transmission lines. The amplifier achieves a peak small-signal gain of 21.3 dB and an average noise figure of 5.4 dB along with power consumption of 30 mW and occupying only 0.38 mm2 pads included. The detailed design procedure and the achieved measurement results are presented in this work.

In this paper, a 10 W ultra-broadband GaN power amplifier (PA) is designed, fabricated, and tested. The suggested design technique provides a more accurate starting point for matching network synthesis and better prediction of achievable circuit performance. A negative-image model was used to fit the extracted optimum impedances based on source-/load-pull technique and multi-section impedance matching networks were designed. The implemented amplifier presents an excellent broadband performance, resulting in a gain of 8.5 ± 0.5 dB, saturated output power of ≥10 W, and power added efficiency (PAE) of ≥23% over the whole bandwidth. The linearity performance has also been characterized. An output third-order intercept point (OIP3) of ≥45 dBm was extracted based on a two-tone measurement technique in the operating bandwidth with different frequency spacing values. The memory effect based on AM/AM and AM/PM conversions was also characterized using a modulated WiMAX signal of 10 MHz bandwidth at 5.8 GHz. Furthermore, a broadband Wilkinson combiner was designed for the same bandwidth with very low loss to extend the overall output power. Excellent agreement between simulated and measured PA performances was also achieved.

In this paper, the concept of load-modulated power amplifiers (PAs) is studied. Two GaN-HEMT power amplifiers (PAs), targeted for high efficiency at maximum and output back-off (OBO) power levels, are designed, implemented, and tested across 1.8–2.2 GHz. The load modulation in the first design is realized by tuning the shunt capacitors in the output matching network. A novel method is employed in the second design, where barium–stronrium–titante is used for the realization of load modulation. The large-signal measurement results across the desired band show 59–70% drain efficiency at 44–44.5 dBm output power for both designs. Using the available tunable technique, the drain efficiency of the PAs is enhanced by 4–20% at 6 dB OBO across the bandwidth.