scholarly journals Validation of Low-Cost Impedance analyzer via Nitrate Detection

Sensors ◽  
2021 ◽  
Vol 21 (19) ◽  
pp. 6695
Author(s):  
Dirk Johannes De Beer ◽  
Trudi-Heleen Joubert

Impedance spectroscopy is a widely used electrochemical technique with a wide variety of applications. Many of these applications benefit from the additional accessibility provided by low-cost impedance devices. With this in mind, a low-cost impedance device was designed for a high performance-to-cost ratio. The performance of this analyzer was validated against a high-performance DropSens µStat-i 400s potentiostat by performing an application-based experiment. Nitrate detection provides a relevant experiment because of the importance of maintaining precise nitrate concentrations to mitigate the impact of nitrate fluctuations on the environment. Dissolved nitrate samples of different concentrations, in the range 3–1000 mg/L, were confirmed colorimetrically and measured with both instruments. A calibration curve of the real impedance matched a sigmoidal transfer, with a linear region for concentrations below 10 mg/L. The device under investigation exhibited an average magnitude error of 1.28% and an average phase error of 0.96∘ relative to the high-performance standard, which validates the performance of the low-cost device. A cost analysis is presented that highlights some of the complexities of cost comparisons.

2021 ◽  
Vol 10 (1) ◽  
Author(s):  
Jun Yin ◽  
Lian Liu ◽  
Yashu Zang ◽  
Anni Ying ◽  
Wenjie Hui ◽  
...  

AbstractHere, an engineered tunneling layer enhanced photocurrent multiplication through the impact ionization effect was proposed and experimentally demonstrated on the graphene/silicon heterojunction photodetectors. With considering the suitable band structure of the insulation material and their special defect states, an atomic layer deposition (ALD) prepared wide-bandgap insulating (WBI) layer of AlN was introduced into the interface of graphene/silicon heterojunction. The promoted tunneling process from this designed structure demonstrated that can effectively help the impact ionization with photogain not only for the regular minority carriers from silicon, but also for the novel hot carries from graphene. As a result, significantly enhanced photocurrent as well as simultaneously decreased dark current about one order were accomplished in this graphene/insulation/silicon (GIS) heterojunction devices with the optimized AlN thickness of ~15 nm compared to the conventional graphene/silicon (GS) devices. Specifically, at the reverse bias of −10 V, a 3.96-A W−1 responsivity with the photogain of ~5.8 for the peak response under 850-nm light illumination, and a 1.03-A W−1 responsivity with ∼3.5 photogain under the 365 nm ultraviolet (UV) illumination were realized, which are even remarkably higher than those in GIS devices with either Al2O3 or the commonly employed SiO2 insulation layers. This work demonstrates a universal strategy to fabricate broadband, low-cost and high-performance photo-detecting devices towards the graphene-silicon optoelectronic integration.


2021 ◽  
Vol 2125 (1) ◽  
pp. 011001

We are glad to introduce you that the 2021 4th International Conference on Mechanical, Electrical and Material Application (MEMA 2021) was successfully held on October 29-31, 2021. In light of worldwide travel restriction and the impact of COVID-19, MEMA 2021 was carried out in the form of virtual conference to avoid personnel gatherings. Because most participants were still highly enthusiastic about participating in this conference, we chose to carry out MEMA 2021 via online platform according to the original schedule instead of postponing it. MEMA 2021 is to bring together innovative academics and industrial experts in the field of Mechanical, Electrical and Material Application to a common forum. The primary goal of the conference is to promote research and developmental activities in Mechanical, Electrical and Material Application and another goal is to promote scientific information interchange between researchers, developers, engineers, students, and practitioners working all around the world. The conference will be held every year to make it an ideal platform for people to share views and experiences in Mechanical, Electrical and Material Application and related areas. We were greatly honored to invited Prof. Kun Li, from Chongqing University, China and Assoc. Prof. Wei Wei, from Xi’an University of Technology, China as our Conference Chairmen. This scientific event brings together more than 100 national and international researchers in mechanical, electrical and material application. During the conference, the conference model was divided into three sessions, including oral presentations, keynote speeches, and online Q&A discussion. In the first part, some scholars, whose submissions were selected as the excellent papers, were given about 5-10 minutes to perform their oral presentations one by one. Then in the second part, keynote speakers were each allocated 30-45 minutes to hold their speeches. We were pleased to invite four distinguished experts to present their insightful speeches. Our first keynote speaker, Prof. Shahid Hussain, Jiangsu University, China. His research interests include MOS-MOF-MXene Nanomaterials, Gas-Sensors, Electrochemical Supercapacitors, Li-S batteries. And then we had Prof. Jie Huang, from Southwest University, China. His research includes RF/Microwave circuits and sensors. Prof. Qiyan Xu, Anhui University of Technology, China. His main research directions are: New process and technology of low cost steel making, Direct reduction and melting reduction, Development of new metallurgical technology - comprehensive utilization of waste resources. Lastly, we were glad to invite Prof. Kun Li, Chongqing University, China. He mainly engaged in additive manufacturing, intelligent 3D net forming, high performance materials and phase transformation, material computing and other research. In the last part of the conference, all participants were invited to join in a WeChat group to discuss and explore the academic issues after the presentations. The online discussion was lasted for about 30-60 minutes. We are glad to share with you that we still received lots of submissions from the conference during this special period. Hence, we selected a bunch of high-quality papers and compiled them into the proceedings after rigorously reviewed them. These papers feature following topics but are not limited to: Mechanical Dynamics and its Applications, Material Physics, Electrical and Electronic Systems and other related topics. All the papers have been through rigorous review and process to meet the requirements of International publication standard. Lastly, we would like to express our sincere gratitude to the Chairman, the distinguished keynote speakers, as well as all the participants. We also want to thank the publisher for publishing the proceedings. May the readers could enjoy the gain some valuable knowledge from the proceedings. We are expecting more and more experts and scholars from all over the world to join this international event next year. The Committee of MEMA 2021 List of Committee member is available in this pdf.


Materials ◽  
2019 ◽  
Vol 12 (6) ◽  
pp. 842 ◽  
Author(s):  
Yanqing Fu ◽  
Qiliang Wei ◽  
Gaixia Zhang ◽  
Yu Zhong ◽  
Nima Moghimian ◽  
...  

In this work, we investigated three types of graphene (i.e., home-made G, G V4, and G V20) with different size and morphology, as additives to a lithium iron phosphate (LFP) cathode for the lithium-ion battery. Both the LFP and the two types of graphene (G V4 and G V20) were sourced from industrial, large-volume manufacturers, enabling cathode production at low cost. The use of wrinkled and/or large pieces of a graphene matrix shows promising electrochemical performance when used as an additive to the LFP, which indicates that the features of large and curved graphene pieces enable construction of a more effective conducting network to realize the full potential of the active materials. Specifically, compared to pristine LFP, the LFP/G, LFP/G V20, and LFP/G V4 show up to a 9.2%, 6.9%, and 4.6% increase, respectively, in a capacity at 1 C. Furthermore, the LFP combined with graphene exhibits a better rate performance than tested with two different charge/discharge modes. Moreover, from the economic and electrochemical performance view point, we also demonstrated that 1% of graphene content is optimized no matter the capacity calculated, based on the LFP/graphene composite or pure LFP.


2012 ◽  
Vol 229-231 ◽  
pp. 845-848
Author(s):  
Xiao Wei Wang

The paper proposes a design scheme of movement encoder with low cost and high performance. The scheme can provide higher precise rotor position signal for motor by a hall-effect latch and a linear hall-effect sensor, and it can also provide rotational speed and direction of motor by a winding with full pole distance, at last we deduce a torque balance equation based on speed and acceleration of motor. The study shows that the scheme with low cost have much higher position precision than traditional rotational transformer and hall-effect position sensor, and it does not exist amplitude error and phase error, function error is small. It is very worthy to the wide application of motor of electric bicycle, wind-driven generator, electric car, and servomotor, etc.


2012 ◽  
Vol 1427 ◽  
Author(s):  
Hamid Kiumarsi ◽  
Hiroyuki Ito ◽  
Noboru Ishihara ◽  
Kenichi Okada ◽  
Yusuke Uemichi ◽  
...  

ABSTRACTA 60 GHz tandem coupler using offset broadside coupled lines is proposed in a WLP (Wafer Level Packaging) technology. The fabricated coupler has a core chip area of 750 μm × 385 μm (0.288 mm2). The measured results show an insertion loss of 0.44 dB, an amplitude imbalance of 0.03 dB and a phase difference of 87.6° at 60 GHz. Also the measurement shows an insertion loss of less than 0.67 dB, an amplitude imbalance of less than 0.31 dB, a phase error of less than 3.7°, an isolation of more than 29.7 dB and a return loss of more than 27.9 dB at the input ant coupled ports and more than 14.3 dB at the direct and isolated ports over the frequency band of 57-66 GHz, covering 60 GHz band both in Japan and US. To the best of our knowledge the proposed coupler achieves the lowest ever reported insertion loss and amplitude imbalance for a 3-dB coupler on a silicon substrate. With its superior performance and lower cost compared to the CMOS counterparts, the proposed coupler is a suitable candidate for low-cost high-performance millimeter-wave systems.


Nanomaterials ◽  
2021 ◽  
Vol 11 (10) ◽  
pp. 2493
Author(s):  
Junlong Yao ◽  
Hanchao Hu ◽  
Zhengguang Sun ◽  
Yucong Wang ◽  
Huabo Huang ◽  
...  

In order to overcome the challenge of synchronously strengthening and toughening polypropylene (PP) with a low-cost and environmental technology, CaCO3 (CC) nanoparticles are modified by tartaric acid (TA), a kind of food-grade complexing agent, and used as nanofillers for the first time. The evaluation of mechanical performance showed that, with 20 wt.% TA-modified CC (TAMCC), the impact toughness and tensile strength of TAMCC/PP were 120% and 14% more than those of neat PP, respectively. Even with 50 wt.% TAMCC, the impact toughness and tensile strength of TAMCC/PP were still superior to those of neat PP, which is attributable to the improved compatibility and dispersion of TAMCC in a PP matrix, and the better fluidity of TAMCC/PP nanocomposite. The strengthening and toughening mechanism of TAMCC for PP involves interfacial debonding between nanofillers and PP, and the decreased crystallinity of PP, but without the formation of β-PP. This article presents a new applicable method to modify CC inorganic fillers with a green modifier and promote their dispersion in PP. The obtained PP nanocomposite simultaneously achieved enhanced mechanical strength and impact toughness even with high content of nanofillers, highlighting bright perspective in high-performance, economical, and eco-friendly polymer-inorganic nanocomposites.


Author(s):  
Ethan Swierski ◽  
Molly Burke ◽  
Maria Arenas ◽  
Jessica Bernat ◽  
James Manzer ◽  
...  

Abstract Due to the impact gait impairments have on afflicted individuals’ lives, there are many efforts to find effective remedies. One example is drop foot, a condition in which the dorsiflexion in the leg falters, and the forefront of the foot drags during walking. One of these is the use of an Ankle Foot Orthosis (AFO), a device worn on the lower extremity of the leg to improve walking ability. Although these orthoses have been improved over time to address a user’s physical needs, material and financial restrictions are still an obstacle. To find the lowest cost AFO design of high performance, a study was conducted to investigate the applications of a simplified design process for an AFO. The design process is a fast, low cost, easy technique of laser cutting thermoplastic resin and bending a drawing into a 3-dimensional AFO. Finding the best AFO possible using this design process was easy, involving making a 2-dimensional CAD model for laser cutting, performing Finite Element Analysis (FEA) simulations and comparing a variety of designs, materials, and configurations for their ability to improve a user’s gait kinematics while also meeting optimal cost and comfort needs.


Author(s):  
D. L. Palmer ◽  
W. F. Waterman

This paper describes the aero-mechanical design and development of a 3.3 kg/sec (7.3 lb/sec), 14:1 pressure ratio two-stage centrifugal compressor which is used in the T800-LHT-800 helicopter engine. The design employs highly nonradial, splitter bladed impellers with swept leading edges and compact vaned diffusers to achieve high performance in a small and robust configuration. The development effort quantified the effects of impeller diffusion and passive inducer shroud bleed on surge margin as well as the effects of impeller loading on tip clearance sensitivity and the impact of sand erosion and shroud roughness on performance. The developed compressor exceeded its performance objectives with a minimum of 23-percent surge margin without variable geometry. The compressor provides a high performance, rugged, low-cost configuration ideally suited for helicopter applications.


Author(s):  
Michelle Blumfield ◽  
Carlene Starck ◽  
Tim Keighley ◽  
Peter Petocz ◽  
Anna Roesler ◽  
...  

Food costs are a barrier to healthier diet selections, particularly for low socioeconomic households who regularly choose processed foods containing refined grains, added sugars, and added fats. In this study, the objectives were to: (i) identify the nutrient density-to-cost ratio of Australian foods; (ii) model the impact of substituting foods with lower nutrient density-to-cost ratio with those with the highest nutrient density-to-cost ratio for diet quality and affordability in low and medium socioeconomic households; and (iii) evaluate food processing levels. Foods were categorized, coded for processing level, analysed for nutrient density and cost, and ranked by nutrient density-to-cost ratio. The top quartile of nutrient dense, low-cost foods included 54% unprocessed (vegetables and reduced fat dairy), 33% ultra-processed (fortified wholegrain bread and breakfast cereals <20 g sugars/100 g), and 13% processed (fruit juice and canned legumes). Using substitution modelling, diet quality improved by 52% for adults and 71% for children across all households, while diet affordability improved by 25% and 27% for low and medium socioeconomic households, respectively. The results indicate that the quality and affordability of the Australian diet can be improved when nutritious, low-cost foods are selected. Processing levels in the healthier modelled diets suggest that some ultra-processed foods may provide a beneficial source of nutrition when consumed within national food group recommendations.


Author(s):  
Carlene S. Starck ◽  
Michelle Blumfield ◽  
Tim Keighley ◽  
Skye Marshall ◽  
Peter Petocz ◽  
...  

The high prevalence of non-communicable disease in New Zealand (NZ) is driven in part by unhealthy diet selections, with food costs contributing to an increased risk for vulnerable population groups. This study aimed to: (i) identify the nutrient density-to-cost ratio of NZ foods; (ii) model the impact of substituting foods with a lower nutrient density-to-cost ratio with those with a higher nutrient density-to-cost ratio on diet quality and affordability in representative NZ population samples for low and medium socioeconomic status (SES) households by ethnicity; and (iii) evaluate food processing level. Foods were categorized, coded for processing level and discretionary status, analyzed for nutrient density and cost, and ranked by nutrient density-to-cost ratio. The top quartile of nutrient dense, low-cost foods were 56% unprocessed (vegetables, fruit, porridge, pasta, rice, nuts/seeds), 31% ultra-processed (vegetable dishes, fortified bread, breakfast cereals unfortified <15 g sugars/100 g and fortified 15–30 g sugars/100 g), 6% processed (fruit juice), and 6% culinary processed (oils). Using substitution modeling, diet quality improved by 59% and 71% for adults and children, respectively, and affordability increased by 20–24%, depending on ethnicity and SES. The NZ diet can be made healthier and more affordable when nutritious, low-cost foods are selected. Processing levels in the healthier, modeled diet suggest that some non-discretionary ultra-processed foods may provide a valuable source of low-cost nutrition for food insecure populations.


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