Additional Carriers Research Articles

Single-Cell VEGF Analysis by Fluorescence Imaging-Microfluidic Droplet Platform: An Immunosandwich Strategy on the Cell Surface.

Despite recent advances in single-cell analysis techniques, the ability of single-cell analysis platforms to track specific cells that secreted cytokines remains limited. Here, we report a microfluidic droplet-based fluorescence imaging platform that can analyze single cell-secreted vascular endothelial growth factor (VEGF), an important regulator of physiological and pathological angiogenesis, to explore cellular physiological clues at the single-cell level. Two kinds of silica nanoparticle (NP)-based immunoprobes were developed, and they were bioconjugated to the membrane proteins of the probed cell surface via the bridging of secreted VEGF. Thus, an immunosandwich assay was built above the probed cell via fluorescence imaging analysis of each cell in isolated droplets. This analytical platform was used to compare the single-cell VEGF secretion ability of three cell lines (MCF-7, HeLa, and H8), which experimentally demonstrates the cellular heterogeneity of cells in secreting cytokines. The uniqueness of this method is that the single-cell assay is carried out above the cell of interest, and no additional carriers (beads or reporter cells) for capturing analytes are needed, which dramatically improves the availability of microdroplets. This single-cell analytical platform can be applied for determining other secreted cytokines at the single-cell level by changing other immune pairs, which will be an available tool for exploring single-cell metabonomics.

InOOH-mediated intergrown heterojunctions for enhanced photocatalytic Performance: Assembly and interfacial charge carrier transferring

Heterojunction photocatalysts with appropriate band structures and abundant interfacial sites present promising photocatalytic performance. Research in this field has generally been focusing on incorporating dissimilar materials to prepare heterojunctions. Few studies show how to construct intergrown heterojunctions that structurally, the interfacial region is narrowed down to atomic scale, facilitating charge carrier transferring and minimising potentially unfavoured band bending. This work first reports the intergrowth between In(OH)3, InOOH and In2O3 that creates an intergrown InOOH/In2O3 and In(OH)3/InOOH heterojunction structures to greatly enhance photocatalytic effect for highly efficient decomposition of perfluorooctanoic acid. The experimental and theoretical investigation indicate that band structure matching is essential for heterojunction photocatalysts. Fast interfacial charge carrier transferring offers additional charge carriers but does not always occur in the heterojunctions where other effects may play the dominated role in interfacial region. We believe that this comprehensive understanding of intergrown heterojunctions would benefit the design and application of high performance photocatalysts.

Operating an ozone-evolving PEM electrolyser in tap water: A case study of water and ion transport

While PEM water electrolysis could be a favourable technique for in situ sanitization with ozone, its application is mainly limited to the use of ultrapure water to achieve a sufficient long-time stability. As additional charge carriers influence the occurring transport phenomena, we investigated the impact of different feed water qualities on the performance of a PEM tap water electrolyser for ozone evolution. The permeation of water and the four most abundant cations (Na+, K+, Ca2+, Mg2+) is characterised during stand-by and powered operation at different charge densities to quantify underlying transport mechanisms. Water transport is shown to linearly increase with the applied current (95 ± 2 mmol A−1 h−1) and occurs decoupled from ion permeation. A limitation of ion permeation is given by the transfer of ions in water to the anode/PEM interface. The unstabilized operation of a PEM electrolyser in tap water leads to a pH gradient which promotes the formation of magnesium and calcium carbonates and hydroxides on the cathode surface. The introduction of a novel auxiliary cathode in the anolytic compartment has shown to suppress ion permeation by close to 20%.

Dual-functional ambipolar non-fused ring electron acceptor as third component and designing similar molecular structure between two acceptors for high-performance ternary organic solar cells

Non-fused ring electron acceptors (NFREAs) are attractive for organic solar cells (OSCs) due to their lower cost and easier synthesis step compared with fused ring type counterparts. Herein, we demonstrate ternary OSCs with two tailor-made NFREAs to improve the efficiency of NFREA-based OSCs. An ambipolar NFREA with dual functions of both electron accepting and donating is employed as third component in ternary blend to provide smooth multiple charge transfer routes without accumulation, and to generate additional photoexcited carriers at the two NFREAs interface. Time-resolved photoluminescence and transient absorption spectroscopy tests confirm the charge transfer between two NFREAs besides between donor and NFREAs. Both space-charge-limited-current mobility and field-effect mobility reveal the ambipolar transport in the third component. In addition, two NFREAs are designed with similar molecular structure to improve the miscibility, in turn, to form homogenously mixed phase with enhanced molecular packing. As a result, the ternary OSC with two NFREAs yields an impressive power conversion efficiency of 15.01%, which is significantly higher than that of binary devices. This work provides an effective strategy to improve the efficiency of NFREA-based OSCs by employing dual-functional ambipolar NFREA and designing similar molecular structure between two NFREAs.

Fabricating Network-Link Acetamiprid-Loading Micelles Based on Dopamine-Functionalized Alginate and Alkyl Polyglucoside To Enhance Folia Deposition and Retention.

The development of an eco-friendly nanopesticide formulation can alleviate the problems of low pesticide utilization and environmental pollution. However, the development of green nanopesticide carriers with ideal physical properties and specific bioavailability is still a challenging task at present. In this study, we propose a novel binary additive pesticide carrier system that is a functional polysaccharide-based polymer/surfactant (Alg-DA/APG) to improve the deposition and retention of pesticide droplets. The self-assembled micelle morphology of Alg-DA/APG and its effect on the apparent viscosity were investigated by transmission electron microscopy (TEM) and a Discovery HR-2 rotational rheometer. Surface tension was carried out to investigate the surface activity and critical micelle concentration (CMC) of Alg-DA/APG. The drop impacting experiments exhibited superior antisplash performance of Alg-DA/APG. Furthermore, a binary additive was used as the carrier material and loaded acetamiprid to prepare nanopesticide formulation Ace@Alg-DA/APG. The encapsulation efficiency (EE) and acetamiprid release behavior from Ace@Alg-DA/APG were also studied. Moreover, the dynamic contact angle (DCA) and retention experiment showed that the DCA and wetting radius at 600 s were, respectively, 6.8 ± 2.39° and 4.044 ± 0.0662 mm for the Ace@0.05 wt % Alg-DA/0.05 wt % APG on the banana foliage surface, and its retention rates on foliage surface were up to 74.80% after washing. The novel binary additive as a nanopesticide carrier has the potential to alleviate the problems of low pesticide utilization and environmental pollution in the future.

Synergistic Effect of Au Interband Transition on Graphene Oxide/ZnO Heterostructure: Experimental Analysis with FDTD Simulation.

We furnish a comprehensive study on light-induced carrier generation due to the synergistic contribution of Au interband transition and graphene oxide (GO)/ZnO heterostructure. Plasmonic gold nanoparticles (Au_nps) are incorporated as a substructure sandwiched between GO and ZnO, assisting in additional photo-induced charge carrier generation. GO is prepared by a single-step plasma-enhanced chemical vapor deposition process. The GO/ZnO heterostructure having an active working area of 0.25 cm2 is created to unleash the pyroelectric property of ZnO, and subsequently, Au_np is introduced at the interface of GO/ZnO. Here, the interband transition of Au_np and its capability for charge carrier generation combined with the excitonic charge carrier generation of the highly crystalline non-centrosymmetric hexagonal wurtzite ZnO enhances the photoresponse. Furthermore, the interaction of Au_np with ZnO and its spatial electric field intensity distribution is demonstrated by finite difference time domain simulation which indicate toward an efficient carrier generation at the interface of Au_np and ZnO. The fabricated heterostructure has an active working wavelength in the UV-A region with the highest responsivity at 375 nm of the electromagnetic spectrum. The ultrafast response time (∼29 μs) of the device is due to the pyro-phototronic effect of the GO/ZnO heterostructure enhanced by the interband transition of Au. In the comparative study of the Au_np-enriched GO/ZnO heterostructure device with a GO/ZnO device, the former shows better performance. Both the devices work in the self-powered mode as well as the photoconductive mode, but with a higher on–off current ratio in the photoconductive mode. Hence, this work helps in properly understanding photo-induced charge generation in a Au interband transition enriched GO/ZnO heterostructure.

Abstract P3-09-02: Mutational assessment of newly diagnosed breast cancer using Germline and tumor genomICs

Abstract Background :For patients with newly diagnosed breast cancer, real-time identification of pathogenic germline mutations in hereditary breast cancer (HBC) genes can provide important information to inform decisions regarding surgery, medical oncology, radiation oncology and to enable activate risk mitigation strategies for unaffected relatives. The potential to dramatically improve outcomes by identifying HBC gene mutation carriers at diagnosis has been demonstrated in the OlympiA. The current strategy of offering germline testing based on NCCN guidelines or validated scores inherently fails to identify all patients with germline HBC gene mutations with adverse consequences for patients and their families. Also, in about 15% of patients without HBC gene mutations, the breast tumors have characteristics suggestive of a more aggressive course. Although universal HBC gene testing has been reported for sub-types of breast cancer or at specialist centers, the MAGIC study is the first prospective trial of unselected invasive breast cancers in general practice combining upfront germline and somatic sequencing with well-validated methods to assess the acceptability of universal testing to patients and clinicians. Methods :This is an Australian multi-center prospective study with 150 consecutive consented patients who are newly diagnosed with nonmetastatic breast cancers. High-grade ductal carcinoma in-situ and pleomorphic lobular cancers were included. Germline testing was performed by whole genome sequencing on DNA from blood or saliva and the data analyzed for actionable HBC gene mutations, including large genomic rearrangements. Whole genome Tumor sequencing was performed on DNA extracted from formalin fixed paraffin-embedded diagnostic tumor and the data analyzed for actionable somatic mutations as well as scoring for homologous recombination deficiency using HRDetect and mutational signatures. The frequency of actionable HBC gene mutations and the number of additional carriers identified compared to standard referral guidelines was the primary objective. For additional analysis, a 3-generation pedigree was done and NCCN, MANCHESTER, and BOADICEA scores were calculated to see whether they would qualify for germline testing according to American and Australian guidelines. Well validated questionnaires were given pre and post-testing for all patients to assess the favorability of universal testing. Health economic analysis will be performed to see the cost vs benefit of offering germline testing. Results :A total of 12 carriers of actionable germline mutations were identified (8.0%) in BRCA1 (n=2), BRCA2 (n=1), PALB2 (n=3), CHEK2 (n=2), ATM (n=2) and PMS2 (n=2). No actionable HBC germline mutations were identified in the 14 cases diagnosed with DCIS only. Only 3 of the 12 mutation positive cases (25%) were referred by the treating clinician for germline testing and including BOADICEA and MANCHESTER scores, would only have identified 6 cases (50%) eligible for germline testing. 9/12 (75%) cases were ER positive including 4 carriers of BRCA1, BRCA2 or PALB2 mutations. Preliminary ascertainment of patient acceptance demonstrates >90% were in favor of universal testing. Among the 12 HBOC gene mutation carriers, the study changed the surgical recommendation for 7 patients (58%) which included the recommendation of B/L salpingo-oophorectomy and radiation management for 3 (25%) patients. Conclusion :Universal germline HBC gene testing is the best method for detecting carriers as over 50% are missed using current. Identifying an actionable mutation in real-time can inform the decision in all specialties involved in the treatment and has a high rate of impacting the clinical decision-making process. This approach was favored by the patients and the clinicians and provided a pathway forward for breast cancer management. Citation Format: Dilanka L De Silva, Anita R Skandarajah, Michelle Sinclair, Maira Kentwell, Lisa Devereux, Magnus Zeethoven, Kirsten Hogg, Luxi Lal, Lesley Stafford, Paul A James, Geoffrey J Lindeman, Gregory B Mann, Ian G Campbell. Mutational assessment of newly diagnosed breast cancer using Germline and tumor genomICs [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr P3-09-02.

High-crystallinity single-walled carbon nanotube aerogel growth: Understanding the real-time catalytic decomposition reaction through floating catalyst chemical vapor deposition

In this study, high-purity single-walled carbon nanotubes (SWCNTs) are synthesized with additional carrier gas through floating catalyst chemical vapor deposition. The presence of Ar during the SWCNT aerogel formation affects to the precursor decomposition and to the formation of different reactive hydrocarbons. Furthermore, the concentration of produced various carbon species is sensitive to the carrier gas compositions. The in-situ sampling methods prove the thermodynamic pathway for the hydrocarbon cracking during carbon nanotube (CNT) aerogel formation process. The addition of Ar promoted the formation of reactive hydrocarbon species, such as CH3, CH4, and C2H4/CO, to improve CNT morphology and graphitization. Ar has improved purity of CNTs compared to when only H2 is used. The synthesized CNTs were narrow in size, and the diameter decreased from 1.8 to 1.2 nm with the carrier gas composition (Rx) according to Ar addition. The IG/ID ratio of the CNTs changed from 78 to 3 at R0.1 and R0.57, respectively. Furthermore, the purity also increased to approximately 10% from 78% to 91% depending on Rx.

Relevant photovoltaic effect in N-doped CQDs/MoS2 (0D/2D) quantum dimensional heterostructure

In this work, a novel kind of solar cell based on the N-CQDs/MoS2 (0D/2D) quantum dimensional heterostructure has been fabricated using a two-dimensional (2D) MoS2 ultrathin layer and zero-dimensional (0D) Nitrogen-doped carbon quantum dots (N-CQDs). The combination of N-CQDs and MoS2 offers good optical and electrical characteristics. The current-voltage (I–V) characteristics of the quantum dimensional heterostructure have been recorded in the dark and under the illumination of solar radiations. A significant current rectification ratio has been observed in dark I–V characteristics. Furthermore, a remarkable shift of −13.49 mA in the I–V curve is observed on the exposure to solar radiation. The fabricated quantum dimensional heterostructure exhibits a significant power conversion efficiency (η) of 4.06% and an open-circuit voltage of 0.83 V. The external quantum efficiency (EQE) spectra support the recorded photovoltaic performance of the heterostructure. The aforementioned results could be ascribed to the effective separation of photogenerated electron-hole pairs at the junction contact. The N-CQDs serve as an electron blocking layer, preventing additional carrier recombination at the metal electrode. Our findings show that N-CQDs/MoS2 heterostructure has a great potential in futuristic low-cost, non-toxic, and highly efficient solar cells for next-generation energy harvesting applications.

NDUFA1 p.Gly32Arg variant in early-onset dementia

Early-onset dementia (EOD) is highly heritable. However, in many EOD cases the genetic etiology remains unknown. Mitochondrial dysfunction is associated with neurodegeneration and the complex I (CI) deficiency is the most common enzyme deficiency in diseases related to oxidative phosphorylation. The X-chromosomal NDUFA1 gene is essential for the activity of CI. Mutations in NDUFA1 are associated with mitochondrial diseases especially with Leigh syndrome. CI deficiency is also associated with neurodegenerative diseases, such as Alzheimer's disease (AD). The aim of this study was to evaluate the role of NDUFA1 variants in EOD patients. Next-generation sequencing panel was used to screen NDUFA1 variants in a cohort of 37 EOD patients with a family history of dementia or an atypical or rapidly progressive course of disease. We identified a hemizygous p.Gly32Arg variant in two brothers with AD. Subsequent screening of the variant in a larger cohort of EOD patients (n = 279) revealed three additional variant carriers (one male and two heterozygote females), suggesting that NDUFA1 variant p.Gly32Arg may play a role in neurodegenerative dementia.

Antigen epitope-TLR7/8a conjugate as self-assembled carrier-free nanovaccine for personalized immunotherapy

Epitope-based vaccine is a promising personalized cancer immunotherapy; however, a simple and effective approach for its bulk manufacturing is challenging. Current vaccination strategies complicate the process by introducing unnecessary components such as additional delivery carriers, and assembly units. Herein, a type of toll-like receptor 7/8 agonist-epitope conjugate (termed as TLR7/8a-epitope) has been developed as a self-assembled and carrier-free nano vaccine platform, which effectively introduces the antigen and adjuvant with maximum precision, resulting in significantly enhanced dendritic cells (DCs) activation through the MyD88-dependent TLR signaling pathway. TLR7/8a-epitope nanovaccine can prolong the local retention and increase drainage efficiency into the lymph node, eliciting a significantly higher level of CD8 T-cell immunity than those of conventional vaccine formulations. The immunization with TLR7/8a-epitope nanovaccine in mice can not only resist the invasion of B16 cancer cells, but also produce significant therapeutic effects against established B16 melanoma tumors. Therefore, the TLR7/8a-epitope nanovaccine, developed by the direct chemical conjugation of antigen peptide with immunoadjuvant, has great advantages of clear and leanest compositions, controllable and definite preparation process, and remarkable therapeutic effects, representing a new appraoch for personalized cancer immunotherapy. Statement of significanceHerein, a kind of toll-like receptor 7/8 agonist-epitope conjugate was developed and spontaneously self-assemble into nanostructure in aqueous solution without the use of any additional constituents, which can be termed as unique carrier-free nanovaccine platform, providing effectually the leanest vaccine components with maximally and precisely loading of antigen and adjuvant.Significantly, the nanovaccine augmented the immunogenicity of antigenic peptide by increasing DCs activation through MyD88-mediated TLR signaling pathways and promoting T-cell priming. Moreover, nanovaccines could prolong the local retention and further increase the efficiency of drainage into dLNs, which was contributing to efficient initiation of epitope-specific memory and effector T-cell immune responses, leading to effective prophylactic and therapeutic antitumor effects.

How Does Fluid Flow Influence Drug Release from Drug Filled Implants?

Drug-filled implants (DFIs) have emerged as an innovative approach to control the delivery of drugs. These devices contain the drug within the structure of the implant itself and avoid the need to include additional drug carrier materials such as a polymers, which are often associated with inflammation and delayed healing/tissue regeneration at the implant site. One common feature of in vitro experiments to generate drug release profiles is stirring or agitation of the release medium. However, the influence of the resulting fluid flow on the rate of drug release from DFIs has yet to be quantified. In this paper we consider two DFIs, which although similar in shape and size, employ different strategies to control the release of drug: a porous pin with pores on the order of μm and a pin drilled with orifices of the order of mm. We develop a multiphysics mathematical model of drug release from these DFIs, subject to fluid flow induced through stirring and show that fluid flow greatly influences the drug release profile for the orifice pin, but that the porous pin drug release profile is relatively insensitive to flow. We demonstrate that drug release from the porous pin may adequately be described through a simplified radial 1D dissolution-diffusion model, while a 3D dissolution-advection-diffusion model is required to describe drug release from the orifice pin. A sensitivity analysis reveals that that the balance of reaction-advection-diffusion in terms of key nondimensional numbers governs the overall drug release. Our findings potentially have important implications in terms of devising the most relevant experimental protocol for quantifying drug release from DFIs.

High-Voltage Repetitive Nanosecond Pulse Generator Utilizing Power Synthesis of Modified Avalanche Transistorized Marx Circuits

In order to further improve the output voltage amplitude and repetitive operation reliability of nanosecond pulse generator (PG) based on avalanche transistor (AT), the method of power synthesis of modularized Marx circuits with transmission line transformer (TLT) is employed in this article. The modified positive <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$4\times11$ </tex-math></inline-formula> -stage Marx circuit introducing base-triggering method is designed and implemented to improve the operation reliability. The triggering synchronization and the consistence of output characteristics of multiple Marx modules with an identical trigger pulse are validated. The feasibility of combining pulses generated from four Marx modules with an optimized four-stage TLT is demonstrated. The influences of the type and quantity of magnetic core and the superimposed stage number of TLT on the output performance of the generator are investigated. The operation characteristics of the generator including output parameters, trigger time-delay, and loop efficiency in the whole working range are evaluated. The experimental results show that the working range of the overall device has been widened significantly with the injection of additional initial carrier. Accordingly, the generator prototype is capable of achieving the output performance with an adjustable voltage amplitude in the range of 7.8–26.7 kV on a matched 300- <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\Omega $ </tex-math></inline-formula> resistive load and 12.2–38.9 kV on the high-resistance load, respectively, a 10%–90% rise time of 3.6 ns, and a full-width at half-maximum (FWHM) of 12.2 ns. A long-term test with the maximum repetition rate of 3 kHz is conducted to realize high-voltage output and high-frequency operation simultaneously.

Numerical investigation of additional gas supply angle influence on flow in jet mill ejector

The results of numerical simulation of the flow in the jet mill ejector which is equipped with an additional gas supply channel have been presented. The influence of the supply system parameters on the nature of the flow in the ejector accelerating tube has been investigated. A comparative analysis of the change in the flow structure in the ejector for different values of the additional gas flow angle has been carried out. The dependences of the flow velocity at the outlet of the accelerating tube, the ejection coefficient and the thickness of the protective layer on the angle of the additional energy carrier supply have been scrutinized. The maximum values of the average output velocities for the given ranges of the additional flow parameters have been determined. Recommendations for the choice of geometric and gas-dynamic parameters of the additional gas flow to ensure the highest efficiency of the acceleration process in the jet mill ejector have been developed. The choice of the angle of the additional gas flow supply, which provides the highest average velocity at the outlet from the accelerating tube with the highest ejection coefficient, has been substantiated.

Enhanced proton conductivity of poly (arylene ether ketone sulfone) containing uneven sulfonic acid side chains by incorporating imidazole functionalized metal-organic framework

In this study, the side-chain type hybrid proton exchange membranes which based on metal-organic frameworks (MOFs) and organic matrix of sulfonated poly (arylene ether ketone sulfone) containing both long and short sulfonic acid side chains (S-C-SPAEKS) were prepared. MOF-801 was used as a template and then imidazole was encapsulated into MOF-801 as additional proton carriers. In imidazole -MOF-801, imidazole was used as a functional group to coordinate with the zirconium metal site of the functional group. Imidazole-MOF-801 and hybrid membranes were characterized by XRD, 1H NMR and FT-IR. These hybrid membranes exhibited excellent proton conductivities and good thermal stabilities. Compared to pure S-C-SPAEKS (0.0487 S cm−1 at 30 °C, 0.0809 S cm−1 at 80 °C), S-C-SPAEKS/0.5% Im-MOF-801 showed a great improvement (0.1205 S cm−1 at 30 °C, 0.1992 S cm−1 at 80 °C), which was about 2.5 times higher than that of pure S-C-SPAEKS and 2 times higher than that of commercial Nafion117 (0.1003 S cm−1 at 80 °C). The results indicated that imidazole functionalized MOFs and uneven side chain structure synergistically made an important contribution to proton transport. This series of hybrid membranes have the potential to be used as alternative proton exchange membranes.

Self-delivery nanomedicine for vascular disruption-supplemented chemo-photodynamic tumor therapy

Tumor vascular blockade is a promising strategy for adjuvant cancer treatment. In this work, a self-delivery nanomedicine is developed based on a vascular disruptor and photosensitizer for tumor synergistic therapy. Specifically, this nanomedicine (designated as CeCA) is comprised of combretastatin A4 (CA4) and chlorine e6 (Ce6) by self-assembly technique. Among which, CA4 could not only induce tubulin inhibition for chemotherapy but also disrupt the vasculature to cause tumor hemorrhage. Moreover, Ce6 is able to generate lots of singlet oxygen (1O2) for synergistic photodynamic therapy (PDT) under light irradiation. It is interesting that the carrier-free CeCA possessed a favorable stability and an improved cellular uptake behavior. After intravenous administration, CeCA prefers to accumulate at tumor site for vascular disruption-supplemented chemo-photodynamic therapy. Notably, CeCA is prepared without additional carriers, which avoids the system toxicity raised by excipients. Consequently, CeCA greatly inhibits the tumor growth and leads to a low side effect in vivo. It might open a window in the development of self-supplementary nanomedicine for synergistic tumor treatment.

Low-Operating-Temperature NO2 Sensor Based on a CeO2/ZnO Heterojunction.

CeO2/ZnO-heterojunction-nanorod-array-based chemiresistive sensors were studied for their low-operating-temperature and gas-detecting characteristics. Arrays of CeO2/ZnO heterojunction nanorods were synthesized using anodic electrodeposition coating followed by hydrothermal treatment. The sensor based on this CeO2/ZnO heterojunction demonstrated a much higher sensitivity to NO2 at a low operating temperature (120 °C) than the pure-ZnO-based sensor. Moreover, even at room temperature (RT, 25 °C) the CeO2/ZnO-heterojunction-based sensor responds linearly and rapidly to NO2. This sensor’s reaction to interfering gases was substantially less than that of NO2, suggesting exceptional selectivity. Experimental results revealed that the enhanced gas-sensing performance at the low operating temperature of the CeO2/ZnO heterojunction due to the built-in field formed after the construction of heterojunctions provides additional carriers for ZnO. Thanks to more carriers in the ZnO conduction band, more oxygen and target gases can be adsorbed. This explains the enhanced gas sensitivity of the CeO2/ZnO heterojunction at low operating temperatures.

Resistive switching of transition metal ferrites on silicon substrate

This letter reports on the development and characterization of ferrite based resistive switching devices that join the excellent multifunctional memory properties of ferrites and silicon processing technologies. The core of the resistive switching devices consists of a single transition metal ferrite (Co, Cu, Ni, and Zn) confirmed through energy dispersive x-ray spectroscopy and x-ray diffraction. The ferrites are spin coated onto processed silicon dies (acting as bottom electrode/substrate) and deposited with a silver top electrode. Both electrodes are active, providing additional charge carriers to the main redox reaction mechanism (found in ferrites), thus helping device stability. Characterization and analysis of the ferrite-silicon devices show low resistive state ohmic conduction as well as the non-linear conducting mechanisms (Schottky Emission and Poole Frenkel) found in previously reported ferrite resistive switching devices. An additional reaction mechanism (space charge limited current) was found that is attributed to the active electrodes through the influx of excess charge carriers.

Керування газо-масопотоками в струминному обладнанні

Based on a numerical simulation of gas flows in an ejector unit and an analysis of grinding chamber acoustic signals, this paper shows ways to increase the efficiency of jet grinding. To prevent ejector speed-up tube wear and to obtain a ground product without impurities, the effect of feeding an additional energy carrier flow on the flow pattern in the speed-up tube of a jet mill was studied. A comparative analysis of the ejector flow pattern as a function of the presence of an additional feed and the speed-up tube shape was carried out. It was shown that the use of a conical nozzle offers a more uniform flow at the ejector outlet. The additional energy carrier feed provides a uniform increase in flow speed and reduces speed-up tube wall wear. The acoustic signals of the mill working zones were related to the jet grinding process parameters, around which a ground product quality control method was developed. The paper presents a technique for determining the material particle size in the energy carrier flow from the results of acoustic monitoring of the process. The technique uses the established relationship between the dispersion of the acoustic signal characteristic frequency and the mass of the corresponding fracture of the mixture in in-flow material transportation. The technique speeds up material particle size determination and improves the finished product quality. An automatic system was developed to control the grinding process by controlling the loading process according to the characteristics of the grinding zone acoustic signals. An operating model of a controlled hopper of a gas jet mill was made. The operability of the control system was verified on a simulation model, which includes a control objet (mill) model and a control system model. It was shown that the system of mill loading automatic control by the characteristics of the grinding zone acoustic signals offers an up to 10 percent increase in mill capacity, which was verified in industrial conditions at Vilnohorsk Mining and Metallurgical Plant.

1/f Noise responses of Ultra-Thin Body and Buried oxide FD-SOI PMOSFETs under total ionizing dose irradiation

This paper investigates the low frequency noise degradation of commercial Ultra-Thin Body and Buried oxide Fully Depleted Silicon on Insulator (UTBB FD-SOI) PMOSFETs are under Total Ionizing Dose (TID) irradiation. According to the experimental results, the 1/f noise of the conduction channel in studied transistors increases differently after irradiation. Based on the carrier number fluctuation (CNF) model with additional carrier mobility fluctuations (CMF), we expand the process of 1/f noise changes at the front and back gates in UTBB FD-SOI devices during TID irradiation. Moreover, the relationship between channel Width/Length ratio (W/L) and the 1/f noise normalized power spectral density at the front gate before and after TID irradiation is also discussed. The trend reducing W/L condition can alleviate 1/f noise degradation in transistors is consistent with the expended theory, which can be a practical reference to develop the UTBB FD-SOI radiation-hardening technology.