Magnetic shielding of long paraboloid structures in the inhomogeneous magnetic field

Abstract: Shielding efficacy of the high-temperature superconducting (HTS) magnetic shields depends on the superconductor properties and on the orientation of the external magnetic field. For precise magnetic field measurements in areas with changing direction of magnetic noise it is important to reduce both the parallel and perpendicular components of the magnetic field. We have designed and fabricated magnetic shields of 25 cm long paraboloid shape with closed sides from second-generation HTS tapes. We have characterized HTS shields in DC and variable frequency AC magnetic fields at 77 K above a copper electromagnet acting as the source of inhomogeneous magnetic noise. The HTS magnetic shields reduce the magnetic field noise penetration and enhance the sensitivity of magnetic field sensors. The measurements were performed with the magnetic shield placed between the noise source and the sensor. 2D finite element analysis using Comsol model was generated and the results were compared with the experimental data of magnetic field dependences of the shielding factor (SF)

Nutrition Facts Recognition from Food Labels Images

In this project we create a diet log application for the consumers based on the their calories intake from different food items. This way the consumer can maintain a regulatory diet and manage accordingly about his/her calories consumption for a day based on the limit set by the consumer itself. This project is implemented in different phases. The first phase includes the image pre-processing which includes median filtering, adaptive thresholding, histogram equalization and segmentation. The second phase includes the optical character recognition on the segmented data. Finally the total calories intake from each food items is added and an alert message is generated to notify the consumer if exceeded day’s limit

Measurements and calculations of transport AC loss in second generation high temperature superconducting pancake coils

Theoretical and experimental AC loss data on a superconducting pancake coil wound using second generation (2 G) conductors are presented. An anisotropic critical state model is used to calculate critical current and the AC losses of a superconducting pancake coil. In the coil there are two regions, the critical state region and the subcritical region. The model assumes that in the subcritical region the flux lines are parallel to the tape wide face. AC losses of the superconducting pancake coil are calculated using this model. Both calorimetric and electrical techniques were used to measure AC losses in the coil. The calorimetric method is based on measuring the boil-off rate of liquid nitrogen. The electric method used a compensation circuit to eliminate the inductive component to measure the loss voltage of the coil. The experimental results are consistent with the theoretical calculations thus validating the anisotropic critical state model for loss estimations in the superconducting pancake coil

Greener, Safer and Better Performing Aqueous Binder for Positive Electrode Manufacturing of Sodium Ion Batteries

P2-type cobalt-free MnNi-based layered oxides are promising cathode materials for sodium-ion batteries (SIBs) due to their high reversible capacity and well chemical stability. However, the phase transformations during repeated (dis)charge steps lead to rapid capacity decay and deteriorated Na+ diffusion kinetics. Moreover, the electrode manufacturing based on polyvinylidene difluoride (PVDF) binder system has been reported with severely defluorination issue as well as the energy intensive and expensive process due to the use of toxic and volatile N-methyl-2-pyrrolidone (NMP) solvent. It calls for designing a sustainable, better performing, and cost-effective binder for positive electrode manufacturing. In this work, we investigated inorganic sodium metasilicate (SMS) as a viable binder in conjunction with P2-Na0.67Mn0.55Ni0.25Fe0.1Ti0.1O2 (NMNFT) cathode material for SIBs. The NMNFT-SMS electrode delivered a superior electrochemical performance compared to carboxy methylcellulose (CMC) and PVDF based electrodes with a reversible capacity of ~161 mAh/g and retaining ~83 % after 200 cycles. Lower cell impedance and faster Na+ diffusion was also observed in this binder system. Meanwhile, with the assistance of TEM technique, SMS is suggested to form a uniform and stable nanoscale layer over the cathode particle surface, protecting the particle from exfoliation/cracking due to electrolyte attack. It effectively maintained the electrode connectivity and suppressed early phase transitions during cycling as confirmed by operando XRD study. With these findings, SMS binder can be proposed as a powerful multifunctional binder to enable positive electrode manufacturing of SIBs and to overall reduce battery manufacturing costs

Visualisation of stabilising particles at the gas solid interface of metal foams

In this article, we demonstrate a technique to visualise the stabilising particles at the gas solid interface of metal foams by employing metallographic etching. This technique is easy to perform and can be applied on a relatively large sample size. The particles present at the gas solid interface of five different types of foams were investigated. Information on the type of particles and the particle coverage could be obtained from this stud

Inactivation of Chk2 and Mus81 Leads to Impaired Lymphocytes Development, Reduced Genomic Instability, and Suppression of Cancer

Chk2 is an effector kinase important for the activation of cell cycle checkpoints, p53, and apoptosis in response to DNA damage. Mus81 is required for the restart of stalled replication forks and for genomic integrity. Mus81Δex3-4/Δex3-4 mice have increased cancer susceptibility that is exacerbated by p53 inactivation. In this study, we demonstrate that Chk2 inactivation impairs the development of Mus81Δex3-4/Δex3-4 lymphoid cells in a cell-autonomous manner. Importantly, in contrast to its predicted tumor suppressor function, loss of Chk2 promotes mitotic catastrophe and cell death, and it results in suppressed oncogenic transformation and tumor development in Mus81Δex3-4/Δex3-4 background. Thus, our data indicate that an important role for Chk2 is maintaining lymphocyte development and that dual inactivation of Chk2 and Mus81 remarkably inhibits cancer

Environmental enrichment preserves hippocampal neurons in diabetes and stressed rats

This study evaluated the effect of Environmental Enrichment (EE) on neuron morphology in the CA1, CA3 and dentate hilus (DH) regions of the hippocampus by quantitating the total dendritic arborizations. EE is a potential intervention for stress and diabetes. It is capable of mitigating diabetes and stress-induced cognitive and memory deficit. Diabetes and stress were induced in male Wistar rats (4-5 weeks). Diabetic and stressed rats were exposed to EE on Day 2 post STZ injection and subsequently once daily for 30 days. All animals were sacrificed on Day 30. The hippocampus was dissected and processed for Golgi staining to quantitate dendritic arborizations at the CA1, CA2 and DH regions. Diabetes (D) and Diabetes+stress (D+S) groups had significantly fewer apical and basal dendritic branching points (ADBP, BDBP) at CA1 (p<0.01), CA3 (p<0.001) and DH (p<0.001) relative to control group (NC). Diabetes and stressed rats exposed to EE: [D+EE and D+S+EE groups] exhibited significantly denser ADBP and BDBP at all regions relative to D (p<0.001) and (D+S+EE) (p<0.001) groups respectively. EE significantly preserved neuronal arborizations in hippocampus of diabetic and stressed rats, suggesting a potential entity of diabetes and stress management