166 research outputs found
Synthesis of Tungsten Oxide Nanoparticles using a Hydrothermal Method at Ambient Pressure
Tungstite (WO3.H2O) nanoparticles were synthesized using a simple and
inexpensive low temperature and low pressure hydrothermal method by adding
hydrochloric acid to diluted sodium tungstate solutions (Na2WO4.2H2O) at
temperatures below 5oC. A heat treatment at temperatures at or above 300oC
resulted in a phase transformation to monoclinic WO3, while preserving the
nanoparticles morphology. The products were characterized using powder x-ray
diffraction, transmission electron microscopy (including electron energy-loss
spectroscopy and electron diffraction) and x-ray photoelectron spectroscopy.Comment: 11 pages, 1 table and 5 figure
Capillary based Li-air batteries for <i>in situ</i> synchrotron X-ray powder diffraction studies
A novel design for in situ X-ray diffraction Li–O2 battery reveals the crystallographic details for the precipitation and decomposition of Li2O2 for the 1st and 2nd cycles of the battery.</p
Fundamental Understanding and Quantification of Capacity Losses Involving the Negative Electrode in Sodium‐Ion Batteries
Knowledge about capacity losses related to the solid electrolyte interphase (SEI) in sodium-ion batteries (SIBs) is still limited. One major challenge in
SIBs is that the solubility of SEI species in liquid electrolytes is comparatively higher than the corresponding species formed in Li-ion batteries. This study
sheds new light on the associated capacity losses due to initial SEI formation, SEI dissolution and subsequent SEI reformation, charge leakage via SEI and
subsequent SEI growth, and diffusion-controlled sodium trapping in electrode particles. By using a variety of electrochemical cycling protocols,
synchrotron-based X-ray photoelectron spectroscopy (XPS), gas chromatography coupled with mass spectrometry (GC-MS), and proton
nuclear magnetic resonance (1H-NMR) spectroscopy, capacity losses due to changes in the SEI layer during different open circuit pause times are
investigated in nine different electrolyte solutions. It is shown that the amount of capacity lost depends on the interplay between the electrolyte chemistry
and the thickness and stability of the SEI layer. The highest capacity loss is measured in NaPF6 in ethylene carboante mixed with diethylene carbonate electrolyte (i.e., 5 μAh h−1/2 pause or 2.78 mAh g·h−1/2 pause) while the lowest value is found in NaTFSI in ethylene carbonate mixed with dimethoxyethance electrolyte (i.e., 1.3 μAh h−1/2 pause or 0.72 mAh g·h−1/2 pause)
A transfer learning approach with convolutional neural network for Face Mask Detection
Due to the epidemic of the coronavirus (Covid-19) and its rapid spread around
the world, the world has faced an enormous crisis. To prevent the spread of the
coronavirus, the World Health Organization (WHO) has introduced the use of
masks and keeping social distance as the best preventive method. So, developing
an automatic monitoring system for detecting facemasks in some crowded places
is essential. To do this, we propose a mask recognition system based on
transfer learning and Inception v3 architecture. In the proposed method, two
datasets are used simultaneously for training including the Simulated Mask Face
Dataset (SMFD) and MaskedFace-Net (MFN) This paper tries to increase the
accuracy of the proposed system by optimally setting hyper-parameters and
accurately designing the fully connected layers. The main advantage of the
proposed method is that in addition to masked and unmasked faces, it can also
detect cases of incorrect use of mask. Therefore, the proposed method
classifies the input face images into three categories. Experimental results
show the high accuracy and efficiency of the proposed method; so, this method
has achieved an accuracy of 99.47% and 99.33% in training and test data
respectivelyComment: 9 pages, in Persian language, 8 figure
The mediating role of assertiveness in the association between family communication patterns and relationships with the opposite sex among adolescent girls
Background: Considering the expansion of friendship between boys and girls during adolescence, as an abnormal behavior in our society and the important role of communication patterns in the family, it is important to investigate the effect of mediating variables on this social phenomenon. The present research has investigated the model of communication with the opposite sex among teenage girls in Birjand city under the influence of communication patterns in the family and the mediating variable of assertiveness.
Methods: This is a correlational study. Sample size was 360 female students of Birjand city. Sampling method was multi-stage cluster random sampling. The data collection tool was a set of questionnaires. We use correlational analysis methods and Structural Equation Model to interpret data.
Results: The fitted model showed communication patterns of family has a significant effect on the relationship with the opposite sex through mediating variable.
Conclusion: the communication pattern of dialogue alone does not play a role in the relationship with the opposite sex, but with increasing assertiveness; it decreases the relationship with the opposite sex
Application of Imaging Technologies in Breast Cancer Detection: A Review Article
One of the techniques utilised in the management of cancer in all stages is multiple biomedical imaging. Imaging as an important part of cancer clinical protocols can provide a variety of information about morphology, structure, metabolism and functions. Application of imaging technics together with other investigative apparatus including in fluids analysis and vitro tissue would help clinical decision-making. Mixed imaging techniques can provide supplementary information used to improve staging and therapy planning. Imaging aimed to find minimally invasive therapy to make better results and reduce side effects. Probably, the most important factor in reducing mortality of certain cancers is an early diagnosis of cancer via screening based on imaging. The most common cancer in women is breast cancer. It is considered as the second major cause of cancer deaths in females, and therefore it remained as an important medical and socio-economic issue. Medical imaging has always formed part of breast cancer care and has used in all phases of cancer management from detection and staging to therapy monitoring and post-therapeutic follow-up. An essential action to be performed in the preoperative staging of breast cancer based on breast imaging. The general term of breast imaging refers to breast sonography, mammography, and magnetic resonance tomography (MRT) of the breast (magnetic resonance mammography, MRM).
Further development in technology will lead to increase imaging speed to meet physiological processes requirements. One of the issues in the diagnosis of breast cancer is sensitivity limitation. To overcome this limitation, complementary imaging examinations are utilised that traditionally includes screening ultrasound, and combined mammography and ultrasound. Development in targeted imaging and therapeutic agents calls for close cooperation among academic environment and industries such as biotechnological, IT and pharmaceutical industries
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