High-Performance Ultraviolet Photodetector Based on a Zinc Oxide Nanoparticle@Single-Walled Carbon Nanotube Heterojunction Hybrid Film

A hybrid film consisting of zinc oxide nanoparticles (ZnO NPs) and carbon nanotubes (CNTs) is formed on a glass substrate using a simple and swift spin coating process for the use in ultraviolet photodetectors (UV PDs). The incorporation of various types of CNTs into ZnO NPs (ZnO@CNT) enhances the performance of UV PDs with respect to sensitivity, photoresponse, and long-term operation stability when compared with pristine ZnO NP films. In particular, the introduction of single-walled CNTs (SWNTs) exhibits a superior performance when compared with the multiwalled CNTs (MWNTs) because SWNTs can not only facilitate the stability of free electrons generated by the O2 desorption on ZnO under UV irradiation owing to the built-in potential between ZnO and SWNT heterojunctions, but also allow facile and efficient transport pathways for electrons through SWNTs with high aspect ratio and low defect density. Furthermore, among the various SWNTs (arc-discharged (A-SWNT), Hipco (H-SWNT), and CoMoCat (C-SWNT) SWNTs), we demonstrate the ZnO@A-SWNT hybrid film exhibits the best performance because of higher conductivity and aspect ratio in A-SWNTs when compared with those of other types of SWNTs. At the optimized conditions for the ZnO@A-SWNT film (ratio of A-SWNTs and ZnO NPs and electrode distance), ZnO@A-SWNT displays a sensitivity of 4.9 × 103 % with an on/off current ratio of ~104 at the bias of 2 V under the UV wavelength of 365 nm (0.47 mW/cm2). In addition, the stability in long-term operation and photoresponse time are significantly improved by the introduction of A-SWNTs into the ZnO NP film when compared with the bare ZnO NPs film.

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Molecular Mechanisms of Zinc Oxide Nanoparticle-Induced Genotoxicity

Materials ◽

10.3390/ma10121427 ◽

2017 ◽

Vol 10 (12) ◽

pp. 1427 ◽

Cited By ~ 25

Author(s):

Agmal Scherzad ◽

Till Meyer ◽

Norbert Kleinsasser ◽

Stephan Hackenberg

Keyword(s):

Dna Damage ◽

Zinc Oxide ◽

Mammalian Cells ◽

Oxidative Dna Damage ◽

Molecular Mechanisms ◽

Consumer Products ◽

Zno Nps ◽

Cytotoxic Effects

Background: Zinc oxide nanoparticles (ZnO NPs) are among the most frequently applied nanomaterials in consumer products. Evidence exists regarding the cytotoxic effects of ZnO NPs in mammalian cells; however, knowledge about the potential genotoxicity of ZnO NPs is rare, and results presented in the current literature are inconsistent. Objectives: The aim of this review is to summarize the existing data regarding the DNA damage that ZnO NPs induce, and focus on the possible molecular mechanisms underlying genotoxic events. Methods: Electronic literature databases were systematically searched for studies that report on the genotoxicity of ZnO NPs. Results: Several methods and different endpoints demonstrate the genotoxic potential of ZnO NPs. Most publications describe in vitro assessments of the oxidative DNA damage triggered by dissoluted Zn2+ ions. Most genotoxicological investigations of ZnO NPs address acute exposure situations. Conclusion: Existing evidence indicates that ZnO NPs possibly have the potential to damage DNA. However, there is a lack of long-term exposure experiments that clarify the intracellular bioaccumulation of ZnO NPs and the possible mechanisms of DNA repair and cell survival.

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Detection method for stability of microcontroller accessories based on biosensor

Journal of Computational Methods in Sciences and Engineering ◽

10.3233/jcm215492 ◽

2021 ◽

pp. 1-14

Author(s):

Yan Ren ◽

Jiayong Liu

Keyword(s):

Process Design ◽

Detection Method ◽

Detection Accuracy ◽

Stability Testing ◽

Term Operation ◽

Existing Problems ◽

Testing Method ◽

And Performance ◽

The Stability

In order to solve the problem of poor accuracy of traditional microcontroller attachment stability testing method, a microcontroller attachment stability testing method based on biosensor was designed to solve the existing problems. The reliability test index of the microcontroller is established, then the interference of the microcontroller accessory is detected and responded, and the interference detection signal of the microcontroller accessory is selected. The process design of stability detection of microcontroller accessories based on biosensor is completed. The experimental results show that the stability detection method based on biosensor designed in this paper can ensure the stability detection accuracy of microcontroller accessories above 80%, which is more accurate than traditional methods. It can be used to evaluate the stability, reliability and performance of microcontroller accessories in long-term operation.

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Performance Stability of Recycle Amine-Free Water-Soluble Coolant in Long Term Operation

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.625.530 ◽

2014 ◽

Vol 625 ◽

pp. 530-535

Author(s):

Kenji Yamaguchi ◽

Yasuo Kondo ◽

Satoshi Sakamoto ◽

Mitsugu Yamaguchi ◽

Ryoichi Nakazawa

Keyword(s):

Environmental Effect ◽

Free Water ◽

Water Soluble ◽

Water Recovery ◽

Machining Processes ◽

Cooling Performance ◽

Recycling System ◽

Term Operation ◽

The Stability

Recently, the concern for the environment has been increasing rapidly. In machining processes, the treatment of water-soluble coolants waste has caused environmental problems. Water-soluble coolants contain surfactants, preservatives, and corrosion inhibitors for maintaining the stability and performance of the coolants. To reduce the management cost and environmental effect of water-soluble coolants, the authors have been studying a recycling system for water-soluble coolants. In the recycling system, oil-free recycle water is isolated from the coolant waste and reused as a diluent of the new coolant. The authors have been developing different types of water recovery methods for the recycling system, and the recovered water from the coolant waste has potential as a diluent for a new coolant. In this report, we focused on the amine (alkanolamine) -free water-soluble coolant. Some amine-free water-soluble coolants have been developed and are commercially available. A reduction in the environmental effect in the waste treatment of coolants is expected with amine-free coolants. We have demonstrated that the amine-free water-soluble coolant has equal or better cooling and lubricating performance compared with the conventional amine-containing coolant. In addition, the amine-free coolant shows good recyclability for the recycling system. The processing time of the recycling treatment of the amine-free coolant has been decreased by half with our recycling process compared with the conventional amine-containing coolant. In this report, we examined the stability, cooling performance and lubricating performance of the recycle amine-free water-soluble coolant in long term operation. The recycle amine-free water-soluble coolant is operated in a 3-axis machining center for several months. We observed concentration, pH, corrosion inhibition performance, cooling performance, and lubricating performance of the coolant. The results from these experiments show the amine-free water-soluble coolant has the advantage to use in the recycling system for water-soluble coolant.

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Long-Term Impact of Zinc Oxide Nanoparticles on Differentiation and Cytokine Secretion of Human Adipose-Derived Stromal Cells

Materials ◽

10.3390/ma12111823 ◽

2019 ◽

Vol 12 (11) ◽

pp. 1823 ◽

Cited By ~ 2

Author(s):

Katrin Radeloff ◽

Andreas Radeloff ◽

Mario Ramos Tirado ◽

Agmal Scherzad ◽

Rudolf Hagen ◽

...

Keyword(s):

Gene Expression ◽

Zinc Oxide ◽

Stromal Cells ◽

Zinc Oxide Nanoparticles ◽

Caspase 3 ◽

Cytokine Secretion ◽

Oxide Nanoparticles ◽

Zno Nps ◽

The Impact

Zinc oxide nanoparticles (ZnO-NPs) are widely utilized, for example in manufacturing paints and in the cosmetic industry. In addition, there is raising interest in the application of NPs in stem cell research. However, cytotoxic, genotoxic and pro-inflammatory effects were shown for NPs. The aim of this study was to evaluate the impact of ZnO-NPs on cytokine secretion and differentiation properties of human adipose tissue-derived stromal cells (ASCs). Human ASCs were exposed to the subtoxic concentration of 0.2 µg/mL ZnO-NPs for 24 h. After four weeks of cultivation, adipogenic and osteogenic differentiation procedures were performed. The multi-differentiation potential was confirmed histologically and using polymerase chain reaction (PCR). In addition, the gene expression of IL-6, IL-8, vascular endothelial growth factor (VEGF) and caspase 3 was analyzed. Over the course of four weeks after ZnO-NPs exposure, no significant differences were detected in the gene expression of IL-6, IL-8, VEGF and caspase 3 compared to non-exposed cells. The differentiation was also not affected by the ZnO-NPs. These findings underline the fact, that functionality of ASCs is likely to be unaffected by ZnO-NPs, despite a long-term disposition of NPs in the cells, supposing that the starting concentration was safely in the non-toxic range. This might provide important information for single-use nanomedical applications of ZnO-NPs.

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Photodegradataion and Stability of a-Si Prepared at High Deposition Rates

MRS Proceedings ◽

10.1557/proc-258-45 ◽

1992 ◽

Vol 258 ◽

Cited By ~ 4

Author(s):

Stan Vepřek ◽

Oliver Ambacher ◽

Milan Vaněček

Keyword(s):

Defect Density ◽

Dye Laser ◽

Plasma Cvd ◽

Initial Value ◽

Deposition Rates ◽

Laser Illumination ◽

High Deposition Temperature ◽

The Stability ◽

Si Films

ABSTRACTA-Si films with a constant optical band gap were prepared by plasma CVD from silane at deposition rates up to 17 Å/s under controllably varied conditons and characterized by a number of techniques. Photodegradation under AM1 simulator has been done for 50 hours and for 4–17 hours under 2 Watt/cm2 dye laser illumination at a wavelength corresponding to an absorption coefficient of about 104 cm-1 up to saturation. Samples with different initial value of σ(d) and σ(ph) show different rates of photodegra-dation, but they reach very similar saturation values. The fast photode-gradation with the dye laser is equivalent to a long term (several thousand hours) photodegradation under AM1. The AMI photodegradation for 50 to 100 hours does not yield any reliable measure of the stability of the films. The best films, which were prepared at a high deposition temperature show a low saturation defect density of about 5·1016 cm-3 (CPM-data).

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Rail Track with Rail Compression

Science & Technique ◽

10.21122/2227-1031-2021-20-3-234-242 ◽

2021 ◽

Vol 20 (3) ◽

pp. 234-242

Author(s):

V. N. Sukhodoev

Keyword(s):

Effective Property ◽

Operating Conditions ◽

Design Parameters ◽

Labor Costs ◽

Term Operation ◽

Rail Track ◽

Loading And Unloading ◽

The Stability ◽

The Cost

The problem of damping the noise on the track, arising from the movement of the train, is solved sufficiently but it is simple, if the rail with spacers is laid inside the longitudinally located band sleeper-mechanism. The result is a layered rail thread, consisting of belts: a rail tape with elastic spacers on three sides, a tie-mechanism tape and a ballast layer. The unity of the layers is carried out due to their own mass. This is the static track without external load. Rail compression is an effective property of rail tracks. It is formed in the sleeper mechanism under the influence of vertical forces with displacements and their horizontal derivatives. When loading the track, the compression is carried out repeatedly with subsequent unloading.n this case, each previous changes in the conditions in work of the track are taken into account in the subsequent cycle of loading and unloading. A rail track with a rail compression is a kind of self-adapting linear system, which is necessary with frequent changes in load and operating conditions for silent performance of a functional purpose. The specificity of this path is that the movement of the wheel creates rail vibration and noise, which are immediately damped by compression with damping. The balance between the occurrence of noise and its suppression is achieved by the ratio of the lengths of half-sleeper shoulders as a lever. The condition for the appearance of a shift of the compression forces in the direction from vertical shoulder of the half-sleepers is the unequal settlements of the horizontal shoulder of the L-shaped half-sleepers and its eccentric loading. As a result of the research, the advantages of a rail track with rail compression have been revealed, which is a guarantor of the stability of the design parameters during long-term operation of the track. The cost of a rail track with rail reduction is halved as a result of steel savings, lower labor costs and operational needs.

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Targeted filling of silica in Nafion by a modified in situ sol–gel method for enhanced fuel cell performance at elevated temperatures and low humidity

Chemical Communications ◽

10.1039/c9cc01221d ◽

2019 ◽

Vol 55 (38) ◽

pp. 5499-5502 ◽

Cited By ~ 5

Author(s):

Guoxiao Xu ◽

Shuai Li ◽

Jing Li ◽

Zhao Liu ◽

Ying Li ◽

...

Keyword(s):

Elevated Temperatures ◽

Sol Gel ◽

Silica Network ◽

Fuel Cell Performance ◽

Term Operation ◽

Ionic Cluster ◽

Low Humidity ◽

The Stability

By facilely utilizing an ionic cluster as a nano-reactor, a silica network can be targeted filled in Nafion to increase the PEMFC performance at elevated temperatures and low humidity. Moreover, the stability of Nafion can be improved for the long-term operation of PEMFC under harsh conditions.

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Effect of Additives Ag and Rare‐Earth Elements Y and Sc on the Properties of Hydrogen Sensors Based on Thin SnO2 Films during Long‐Term Testing

Coatings ◽

10.3390/coatings9070423 ◽

2019 ◽

Vol 9 (7) ◽

pp. 423 ◽

Cited By ~ 7

Author(s):

Maksimova ◽

Almaev ◽

Sevastyanov ◽

Potekaev ◽

Chernikov ◽

...

Keyword(s):

Tin Dioxide ◽

Oxygen Adsorption ◽

Hydrogen Sensors ◽

Band Bending ◽

Term Operation ◽

Adsorption Sites ◽

Effect Of Additives ◽

Clean Air ◽

The Stability

The paper presents the results of an investigation of the nanostructure, elements, and phase composition of thin (100–140 nm) tin dioxide films obtained via magnetron sputtering and containing Ag, Y, Sc, Ag + Y, and Ag + Sc additives in the volume. Electrical and gas‐sensitive characteristics of hydrogen sensors based on these films with dispersed Pt/Pd layers deposited on the surface were studied. The additives had a significant effect on the nanostructure of the films, the density of oxygen adsorption sites on the surface of tin dioxide, the band bending at the grain boundaries of tin dioxide, the resistance values in pure air, and the responses to hydrogen in the concentration range of 50–2000 ppm. During the long‐term tests of most of the samples studied, there was an increase in the resistance of the sensors in clean air and in the response to hydrogen. It has been established that the joint introduction of Ag + Y into the volume of films prevents the increase in the resistance and response. For these sensors based on thin films of Pt/Pd/SnO2:Sb, Ag, Y the responses to 100 and 1000 ppm of H2 are 25 and 575, correspondingly, the response time at exposure to 100 and 1000 ppm of H2 are 10 and 90 s, the recovery time at exposure to 100 and 1000 ppm of H2 17 and 125 s. Possible mechanisms of the effect of additives on the properties of sensors and the stability of their parameters during long‐term operation were considered.

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Influence of zinc oxide nanoparticles on anaerobic digestion of waste activated sludge and microbial communities

RSC Advances ◽

10.1039/d0ra08671a ◽

2021 ◽

Vol 11 (10) ◽

pp. 5580-5589

Author(s):

Shutao Wang ◽

Lingbo Chen ◽

Hao Yang ◽

Zhisheng Liu

Keyword(s):

Zinc Oxide ◽

Anaerobic Digestion ◽

Activated Sludge ◽

Microbial Communities ◽

Zinc Oxide Nanoparticles ◽

Waste Activated Sludge ◽

Oxide Nanoparticles ◽

Zno Nps

The influence of long-term exposure of zinc oxide nanoparticles (ZnO NPs) to waste activated sludge on anaerobic digestion and microbial communities was studied.

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Stability Analysis on the Long-Term Operation of the Horizontal Salt Rock Underground Storage

Advances in Civil Engineering ◽

10.1155/2021/6674195 ◽

2021 ◽

Vol 2021 ◽

pp. 1-13

Author(s):

Chengzhong Zhang ◽

Qiang Zhang ◽

Weiwei Li ◽

Zhanping Song ◽

Junbao Wang

Keyword(s):

Underground Storage ◽

Salt Rock ◽

Height Ratio ◽

Design Capacity ◽

Term Operation ◽

Operation Process ◽

The Stability ◽

Rock Deposit ◽

Optimal Diameter

The construction of the vertical cavern in the salt dome deposit can meet the requirements of both storage capacity and tightness. However, if the vertical cavern is still used as the design shape of the salt rock underground storage in the layered salt rock deposit, the high design capacity cannot be guaranteed while the tightness is satisfied. In this case, the use of a large-span horizontal cavern as the design shape of the salt rock storage can not only effectively increase the design capacity of the storage, but also solve the problems such as the stability and tightness of the storage during the operation period by improving the structural form and working mode. Based on this, the ellipsoid-shaped horizontal salt rock underground storage is taken as an example, and a single-cavern horizontal salt rock underground storage model with different diameter-to-height ratios is established by using FLAC3D software. The change law of vertical and horizontal displacements, volume loss rate, and plastic zone distribution of salt rock storage changing with the diameter-to-height ratio are studied, and the optimal diameter-to-height ratio is determined. And then the long-term operation process of the double-cavern horizontal salt rock underground storage under the optimal diameter-to-height ratio is simulated, and the optimal pillar width is obtained.

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