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Trillion of cigarette butts are annually littered without being recycled. This work aims at valorizing the whole cigarette butts and their components (paper, filter and tobacco) into Fe‐Nx‐C electrocatalysts for oxygen reduction reaction (ORR) in acid and alkaline media. The pristine wastes were pyrolyzed at 450 °C, activated with KOH at 700 °C, blended with iron phthalocyanine (FePc) precursor, and heat‐treated at 600 °C to produce a robust Fe‐Nx‐C material with ORR active units. The effect of the cigarette components on the final electrocatalytic activity was evaluated by thoroughly investigating the surface chemistry with XPS. The electrocatalysts displayed similar results among the different components in both media due to comparable surface chemistry, especially concerning the nitrogen functional groups. The highest performance was obtained in alkaline where the electrocatalysts from whole cigarettes and paper (CIGF_450 and CIGPF_450) showed an E1/2 of 0.89 V vs RHE, slightly larger than that of Pt/C with 40 wt % of Pt, which encouraged to replace Pt‐based electrocatalysts in alkaline fuel cells. [ABSTRACT FROM AUTHOR]

Fill-finish of parenteral formulations represents a crucial step in the pharmaceutical industry that necessitates careful monitoring of product stability down the line. Shear stress and interfacial stress are two elements that threaten product stability, the respective contributions of which are still up for debate. This article focuses on the analysis of shear stress in the sampling phase of the filling line. Specifically, Computational Fluid Dynamics (CFD) simulations were employed to determine the shear stress distribution experienced by a protein-based parenteral drug as it passes through sampling fittings of various shapes under laminar and turbulent regime conditions. Rather than seeking the specific mechanism triggering the destabilization of a product, an attempt was made to analyze the fluid dynamics within these fittings and offer further understanding of the resulting shear stress. In addition, information was collected on the product path within the fittings, which allowed the identification of equations suitable for describing the shear stress distribution. The proposed approaches made it possible to consider the actual flowrate subjected to a given shear stress at a given time. Finally, a comparison was drawn with respect to the fluid dynamics within classical straight tubing to outline differences. This study revealed that the shear stress experienced within the fittings was higher than that in the tubing. Moreover, significant differences were reported in the T-fitting case under turbulent conditions. [ABSTRACT FROM AUTHOR]

Parenteral products appear to be sensitive to process conditions in bioprocessing steps, such as interfacial stress and shear stress. The combination of these elements is widely believed and proven to influence product stability, but the defined roles of these players in the product damage process have not yet been identified. The present work addresses a current industrial problem, by focusing on the analysis of shear stress on protein-based therapeutics flowing in tubing by means of Computational Fluid Dynamics simulations. The purpose of this article is not to pinpoint the mechanism triggering the damage of the product, but it represents the first step towards wider experimental investigations and introduces a new strategy to quantify the average shear stress. The field of scale-down approaches, used to scale the commercial process down to the laboratory level, is also explored. Since quality control is critical in the pharmaceutical realm, it is essential that the scale-down approach preserves the same stress exposure as the commercial scale, which in the present work is considered to be that resulting from shear effects. Therefore, a new approach for scaling down the commercial process is proposed, which has been compared with traditional approaches and shown to provide greater representativeness between the two scales. [ABSTRACT FROM AUTHOR]

A remote phase sensing scheme is proposed, inspired by the high sensitivity of the entanglement produced by coherent multimode photon addition on the phase set in the remote heralding apparatus. By exploring the case of delocalized photon addition over two modes containing identical coherent states, the optimal observable to perform remote phase estimation from heralded quadrature measurements is derived. The technique is experimentally tested with calibration measurements and then used for estimating a remote phase with a sensitivity that is found to scale with the intensity of the local coherent states, which never interacted with the sample. [ABSTRACT FROM AUTHOR]

We present a study on the radiation tolerance and timing properties of 3D diamond detectors fabricated by laser engineering on synthetic Chemical Vapor Deposited (CVD) plates. We evaluated the radiation hardness of the sensors using Charge Collection Efficiency (CCE) measurements after neutron fluences up to 10 16 n/cm 2 (1 MeV equivalent.) The radiation tolerance is significantly higher when moving from standard planar architecture to 3D architecture and increases with the increasing density of the columnar electrodes. Also, the maximum applicable bias voltage before electric breakdown increases significantly after high fluence irradiation, possibly due to the passivation of defects. The experimental analysis allowed us to predict the performance of the devices at higher fluence levels, well in the range of 10 16 n/cm 2 . We summarize the recent results on the time resolution measurements of our test sensors after optimization of the laser fabrication process and outline future activity in developing pixel tracking systems for high luminosity particle physics experiments. [ABSTRACT FROM AUTHOR]

We investigate radiation-induced effects on the DC, AC and thermal characteristics of high-performance SiGe HBTs fabricated on thin-film SOI. TCAD simulations indicate novel heavy-ion charge collection phenomena resulting from the unique [C.sub.B][E.sup.B]C device layout of this technology platform. Index Terms--C-SiGe, Heterojunction bipolar transistors, radiation effects, SiGe HBT, silicon-on-insulator (SOI), TCAD.

The impact of 63.3 MeV proton and 10 keY x-ray irradiation on the DC and AC performance of complementary (npn + pnp) SiGe HBTs on thick-film SOI is investigated. Proton and x-ray induced changes in the forward and inverse Gummel characteristics, the output characteristics, and avalanche multiplication are reported for both npn and pnp SiGe HBTs, at both room temperature (300 K) and at cryogenic temperatures (down to 30 K). Comparison of room temperature and cryogenic data suggests interface trap formation at two distinct physical locations in the transistors. Experimental data and calibrated TCAD simulations are used to compare the radiation response of both thick-film SOI devices and thin-film SOI SiGe HBTs. Index Terms--C-SiGe, heterojunction bipolar transistors, radiation effects, SiGe HBT, silicon-on-insulator, SOI, TCAD.

A comprehensive investigation of the performance dependencies of irradiated SiGe precision voltage reference circuits on 1) total ionizing dose (TID), 2) circuit topology, and 3) radiation source is presented. Two different bandgap voltage references were designed using a first-generation (50-GHz) SiGe BiCMOS technology platform, and subsequently exposed to X-rays at doses of 1080 krad(Si[O.sub.2]) and 5400 krad(Si[O.sub.2]). The degradation in circuit performance following X-ray irradiation depends on both the TID level and the chosen circuit topology. Measurement results show that large TID levels can significantly shift the magnitude of the output voltage. Explanations for the observed shifts are provided by utilizing detailed analyses of the two circuit topologies and considering device-to-circuit interactions. The primary factor responsible for the difference in the circuit response before and after irradiation can be attributed to the excess base leakage current in the SiGe HBT. To investigate the impact of radiation source, the circuit topology showing the worst-case degradation from the X-ray experiment was independently exposed to 63-MeV protons at the same effective TID level. A clear source dependence in the circuit response was observed, and possible origins of this behavior are identified. Index Terms--BiCMOS analog integrated circuits, heterojuction bipolar transistors, ionization damage, proton radiation effects, SiGe, SiGe HBTs, X-rays.

We investigate transistor-level layout-based techniques for SEE mitigation in advanced SiGe HBTs. The approach is based on the inclusion of an alternate reverse-biased pn junction (n-ring) designed to shunt electron charge away from the sub-collector to substrate junction. The inclusion of the n-ring affects neither the dc nor ac performance of the SiGe HBT and does not compromise its inherent multi-Mrad TID tolerance. The effects of ion strike location and angle of incidence, as well as n-ring placement, area, and bias on charge collection are investigated experimentally using a 36 MeV [O.sub.2] microbeam. The results indicate that charge shunting through the n-ring can result in up to a 90% reduction in collector collected charge for strikes outside the DT and a 18% reduction for strikes to the emitter center. 3-D transient strike simulations using NanoTCAD are used to verify the experimental observations, as well as shed insight into the underlying physical mechanisms. Circuit implications for this RHBD technique are discussed and recommendations made. Index Terms--Charge collection, deep trench (DT), ion beam induced charge collection (IBICC), NanoTCAD, radiation hardening by design (RHBD), silicon-germanium (SiGe), SiGe HBT, single event effects (SEE).

The inverse mode performance of four distinct generations of SiGe HBTs is investigated and is found to improve impressively with generational scaling. Results show that the improved inverse mode performance with scaling would allow for improved design flexibility and could potentially be use to design novel circuits where speed is not the major driving factor.

A comprehensive investigation of the effects of proton irradiation on the performance of SiGe BiCMOS precision voltage references intended for extreme environment operational conditions is presented. The voltage reference circuits were designed in two distinct SiGe BiCMOS technology platforms (first generation (50 GHz) and third generation (200 GHz)) in order to investigate the effect of technology scaling. The circuits were irradiated at both room temperature and at 77 K. Measurement results from the experiments indicate that the proton-induced changes in the SiGe bandgap references are minor, even down to cryogenic temperatures, clearly good news for the potential application of SiGe mixed-signal circuits in emerging extreme environments. Index Terms--BiCMOS analog integrated circuits, heterojuction bipolar transistors, proton radiation effects.

The off-state drain current leakage characteristics of 130 nm CMOS technology are investigated using x-ray irradiation and operating temperature as variables. Radiation-induced interface traps in the gate oxide to gate-drain overlap region strongly enhance the off-state leakage as a function of gate bias. Due to the thin gate oxide in these 130 nm devices, we find that drain-edge direct tunneling is more plausible than conventional gate-induced-drain-leakage in explaining the observed increase in drain leakage. Radiation-induced traps in the shallow trench isolation oxide create parasitic channels in the p-well and produce another source of off-state drain leakage with increasing total dose. The drain current increase from both the gate overlap region and the shallow trench edge are enhanced with increasing total dose and suppressed by cooling. Index Terms--CMOS, cryogenic, GIDL, off-state leakage current, shallow trench isolation, STI, total dose radiation effects.

We present an investigation of the observed variations in the total dose tolerance of the emitter-base spacer and shallow trench isolation oxides in a commercial 200 GHz SiGe HBT technology. Proton, gamma, and X-ray irradiations at varying dose rates are found to produce drastically different degradation signatures at the various oxide interfaces. Extraction and analysis of the radiation-induced excess base current, as well as low-frequency noise, are used to probe the underlying physical mechanisms. Two-dimensional calibrated device simulations are employed to correlate the observed results to the spatial distributions of carrier recombination in forward- and inverse-mode operation for both pre- and post-irradiation levels. Possible explanations of our observations are offered and the implications for hardness assurance testing are discussed. Index Terms--Dose enhancement, hardness assurance, low-frequency noise, silicon-germanium (SiGe), hetero-junction bipolar transistor, total ionizing dose.

X-ray total ionizing dose effects in both fully-depleted and partially-depleted SiGe HBT-on-SOI transistors are investigated at room and at cryogenic temperatures for the first time. Devices irradiated in grounded and forward-active mode configurations exhibit a different behavior depending on the collector doping of the device. The degradation produced by 10 keV x-rays is compared to previously reported 63 MeV proton results on the same fully-depleted SiGe HBT-on-SOI devices, showing decreased degradation for proton irradiation. Both collector and substrate bias are shown to affect the two-dimensional nature of the current flow in these devices, resulting in significant differences in the avalanche multiplication characteristics (hence, breakdown voltage) across temperature. Index Terms--Heterojunction bipolar transistors, radiation effects, SiGe HBT, silicon-on-insulator technology, SOI, TCAD.

Proton radiation effects in vertical SiGe HBTs fabricated on CMOS-compatible silicon-on-insulator (SOI) are investigated for the first time. Proton irradiation at 63 MeV is found to introduce base leakage current at low base-emitter voltage, delay the onset of Kirk effect at high injection, and increase the frequency response of SiGe HBTs on SOI. The latter two effects are in contrast to those found in conventional bulk SiGe HBTs. Proton irradiation also generates positive fixed oxide and interface charge in the buried oxide, which alters both AI-1 and B[V.sub.CEO] in the SiGe HBT by modulating the electric field in the collector region. Index Terms--HBT, radiation, SiGe, SOI.

A novel route for the valorization of waste into valuable products was developed. Surgical masks commonly used for COVID 19 protection by stopping aerosol and droplets have been widely used, and their disposal is critical and often not properly pursued. This work intended to transform surgical masks into platinum group metal‐free electrocatalysts for oxygen reduction reaction (ORR) and hydrogen evolution reaction (HER) as well as into crude oil. Surgical masks were subjected to controlled‐temperature and ‐atmosphere pyrolysis, and the produced char was then converted into electrocatalysts by functionalizing it with metal phthalocyanine of interest. The electrocatalytic performance characterization towards ORR and HER was carried out highlighting promising activity. At different temperatures, condensable oil fractions were acquired and thoroughly analyzed. Transformation of waste surgical masks into electrocatalysts and crude oil can open new routes for the conversion of waste into valuable products within the core of the circular economy. [ABSTRACT FROM AUTHOR]

Color vision is considered a marker of cone function and its assessment in patients with retinal pathology is complementary to the assessments of spatial vision [best-corrected visual acuity (BCVA)] and contrast detection (perimetry). Rod-cone and chorioretinal dystrophies—such as choroideremia—typically cause alterations to color vision, making its assessment a potential outcome measure in clinical trials. However, clinical evaluation of color vision may be compromised by pathological changes to spatial vision and the visual field. The low vision Cambridge Color Test (lvCCT) was developed specifically to address these latter issues. We used the trivector version of the lvCCT to quantify color discrimination in a cohort of 53 patients with choroideremia. This test enables rapid and precise characterization of color discrimination along protan, deutan, and tritan axes more reliably than the historically preferred test for clinical trials, namely the Farnsworth Munsell 100 Hue test. The lvCCT demonstrates that color vision defects—particularly along the tritan axis—are seen early in choroideremia, and that this occurs independent of changes in visual acuity, pattern electroretinography and ellipsoid zone area on optical coherence tomography (OCT). We argue that the selective loss of tritan color discrimination can be explained by our current understanding of the machinery of color vision and the pathophysiology of choroideremia. [ABSTRACT FROM AUTHOR]

Various formulations for electroless deposition, to obtain continuous nanometre-sized and micrometre-sized films of palladium on copper, were compared. We deposited ultrathin films using displacement plating formulations. We obtained continuous films with an equivalent thickness between 6 and 22 nm, measured by exploiting the K-ratio method with SEM-EDS of Pd layers. The Pd films obtained in this step of the work represent a cost-effective catalytic substrate. As a second step, we selected chemical plating as the procedure to obtain palladium films with a thickness in the micrometre range. An ammonia-based Pd chemical plating bath represent one of the most effective chemical plating formulations. To prevent copper substrates from being damaged by ammonia, displacement plating with palladium was also applied as a pre-treatment to make the use of these plating baths a viable way to obtain thicker palladium coatings. Palladium films showing good adherence, compact morphology, and a thickness over 1.5 μm were obtained, proving that the combination of two different electroless techniques was the key to develop a sustainable procedure for micrometre-sized palladium coatings, which could substitute electroplating of Pd in galvanic industry for decorative applications. [ABSTRACT FROM AUTHOR]

It is demonstrated that the recently developed technique of delocalized single photon addition may generate discorrelation, a new joint statistical property of multimode quantum light states, whereby the number of photons in each mode can take any value individually, but two modes together never exhibit the same. By coherently adding a single photon to two identical coherent states of light in different temporal modes, the first experimental observation of discorrelation is provided. The capability of manipulating this statistical property has applications in scenarios involving the secure distribution of information among untrusted parties, like in the so‐called "mental poker" games. [ABSTRACT FROM AUTHOR]

Electrocatalytic hydrogen oxidation (HOR) and evolution (HER) reactions under alkaline conditions are kinetically sluggish processes even when Pt catalysts are employed. Despite having markedly slower kinetics, nanostructured nickel catalysts represent a cheaper and more sustainable alternative to benchmark Pt-based systems. Accordingly, researchers seek to develop Ni nanoparticle-based materials with enhanced electrocatalytic performance through the exploitation of favorable and catalytically advantageous metal–support interactions. In this contribution, we report the study of various N-doped/decorated carbon nanotubes (N-CNTs) as carriers for nickel nanoparticles (Ni-NPs), prepared by the decomposition of Ni-(COD)2 as a metal precursor, a synthetic method that does not require organic stabilizers. All materials are thoroughly characterized (XPS, HR-TEM, STEM, and XRD) and tested as electrocatalysts for HOR and HER under an alkaline environment. We demonstrate how an increase in the nanotube surface basicity dictated by the presence of N-basic functional groups tunes the NiOx content of the metallic Ni NP surface, conferring higher electrocatalytic performance to the composites. Ni-NPs supported on N-CNTs prepared by exohedral functionalization of multiwalled carbon nanotubes with NH-aziridine functional groups (Ni/CNT-NAz) exhibit the highest HOR activity (16 A gNi–1 at 150 mV vs RHE). In terms of their performance for H2 evolution, Ni/CNT-NAz exhibits better onset potential and activity compared to its Ni-based counterpart prepared from pure-carbon networks (Ni/CNT). Worthy of note, Ni/CNT-NAz exhibited an HER Tafel slope (66 mV dec–1) approaching that of benchmark Pt electrocatalysts. [ABSTRACT FROM AUTHOR]

Due to the sluggish kinetics of the hydrogen oxidation reaction (HOR) in alkaline electrolytes, the development of more efficient HOR catalysts is essential for the next generation of anion‐exchange membrane fuel cells (AEMFCs). In this work, CeOx is selectively deposited onto carbon‐supported Pd nanoparticles by controlled surface reactions, aiming to enhance the homogenous distribution of CeOx and its preferential attachment to Pd nanoparticles, to achieve highly active CeOx‐Pd/C catalysts. The catalysts are characterized by inductively coupled plasma–atomic emission spectroscopy, X‐ray diffraction, high‐resolution transmission electron microscopy, scanning transmission electron microscopy (STEM), electron energy loss spectroscopy, and X‐ray photoelectron spectroscopy to confirm the bulk composition, phases present, morphology, elemental mapping, local oxidation, and surface chemical states, respectively. The intimate contact between Pd and CeOx is shown through high‐resolution STEM maps. The oxophilic nature of CeOx and its effect on Pd are probed by CO stripping. The interfacial contact area between CeOx and Pd nanoparticles is calculated for the first time and correlated to the electrochemical performance of the CeOx‐Pd/C catalysts. Highest recorded HOR specific exchange current (51.5 mA mg−1Pd) and H2–O2 AEMFC performance (peak power density of 1,169 mW cm−2 mgPd−1) are obtained with a CeOx‐Pd/C catalyst with Ce0.38/Pd bulk atomic ratio. [ABSTRACT FROM AUTHOR]