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Journal of Advanced Dielectrics 2021年第1期11卷 1-5页

作者： bhoopendra singh Vivek Pratap Mohit Katiyar S.M.Abbas Y.K.Sharma A.M.Siddiqui N.Eswara Prasad Department of Postgraduate Studies and Research in Physics and Electronics Rani Durgavati Vishwavidyalaya Jabalpur Madhya Pradesh Pachpedi Jabalpur 482001 Madhya PradeshIndia Department of Physics Jamia Millia Islamia Jamia Nagar New Delhi 110025NCT DelhiIndia Defence Materials and Stores Research and Development Establishment(DMSRDE)PO DMSRDE GT RoadKanpur 208013Uttar PradeshIndia

In this study,carbon black(CB)powder-loaded polyurethane(PU)composites(CB-PU composites)were prepared by melt mixing method with different volume percentages(45,50,55,58 and 61 vol.%)of CB in the PU *** prepared CB-PU composites had been further studied for surface morphology using the field-emission scanning electron microscopy(FESEM)*** properties in terms of real permittivity(ε′)and imaginary permittivity(ε′′)of the fabricated composites were computed using an Agilent E8364B vector network analyzer in the frequency range of 8-12 GHz(X-band).Dielectric loss factor of the prepared CB-PU composites was computed in terms of the dielectric loss tangent(tanδ_(e)=ε′′/ε′).Microwave absorbing properties were appraised in terms of the reflection loss(RL)which in turn was calculated for varying thicknesses of the prepared composites from the measured real and imaginary permittivity *** minimum RL was observed as−20.10 dB for the absorber with a thickness of 2.2 mm and the bandwidth achieved was 1.92 GHz for RL≤−10 *** on the above results these CB-PU composites have potential use as effective microwave absorbers in 8-12-GHz(X-band)frequency range.

关键词： Carbon black dielectric materials polymeric composites complex permittivity absorbing properties

Atypical Olfactory Neuroblastoma Presenting as Sinonasal Polyposis with Nasopharyngeal Extension: A Case Report

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International Journal of Otolaryngology and Head & Neck Surgery 2015年第5期4卷 394-400页

作者： Jagdish Prasad Purohit Chandra Bhan bhoopendra singh Ajay Pratap singh Siva Selvaraj Manish Pandey Vijay Krishna Sharma Department of ENT Head and Neck Surgery MLB Medical College Jhansi India

Background: Olfactory neuroblastoma also known as Esthesioneuroblastoma (ENB) is a tumor arising from the basal layer of olfactory epithelium in the superior recess of the nasal cavity in the region of cribriform plate. Incidence peaks once in 11 - 20 years of age and again in 50 - 60 years of age. It is equally found in men and women. Aim: The main aim of this case report is to characterize the clinical features of ENB showing nasopharyngeal involvement and its importance in the differential diagnosis of sinonasal neuroendocrine malignancies. Case presentation: Two cases are reported. The first case was a 21-year-old male with symptoms of nasal obstruction, recurrent epistaxis, nasal discharge, headache and paresthesia over the face with an evolution of 1 year with no previous history of trauma. Diagnostic nasal endoscopy revealed reddish gray mass filling bilateral nasal cavities. Posterior rhinoscopy revealed mass coming through choanae and filling the nasopharynx. Endoscopic resection of tumor was done and postoperatively all the symptoms of the patient resolved. The second case was a 62-year-old male with complaints of nasal obstruction, nasal discharge, recurrent epistaxis, anosmia and difficulty in swallowing. On computed tomography, anteriorly, the mass was extending up to external nares and posteriorly up to the nasopharynx, superiorly up to nasal roof and inferiorly up to hard palate. No obvious erosion of floor of anterior cranial fossa was seen. No intracranial extension was seen. Surgery was advised but patient refused to undergo any treatment. Conclusion: This study highlights the characteristics and clinical features of ENB showing nasopharyngeal involvement and their importance in the differential diagnosis of sinonasal neuroendocrine malignancies.

关键词： Esthesioneuroblastoma Cribriform Plate Neuroectodermal

Tumour Associated Tissue Eosinophilia as a Prognostic Indicator in Squamous Cell Carcinoma of Upper Aerodigestive Tract

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International Journal of Otolaryngology and Head & Neck Surgery 2016年第2期5卷 54-58页

作者： Chandra Bhan Kartikeya Purohit Jagdish Prasad Purohit Ajay Pratap singh bhoopendra singh Siva Selvaraj Manish Pandey Vineet Kumar Vineet Kumar Department of ENT Head and Neck Surgery MLB Medical College Jhansi India

Immune response is known to develop against malignant tumours. Malignant tumours express newer antigen on their cell surface membrane which elicit immunological reaction in and around tumoural tissue. In early part of immune reaction neutrophil, eosinophil migrates followed by monocyte-macrophage cell. Tumor associated tissue eosinophilia (TATE) is believed to play a significant role in the biological behavior of the carcinoma. Eosinophil infiltrate in association with the head and neck squamous cell carcinoma (SCC) have been reviewed from time-to-time. The significance of such an association has been variably thought to be either a potential diagnostic tool for stromal invasion or as a prognostic indicator. The aim of this study was to investigate and evaluate the possible role of the tumour associated tissue eosinophilia (TATE) as a predictive indicator for the grading and establishing prognosis of the upper aerodigestive tract squamous cell carcinoma (SCC).

关键词： Tumour Associated Tissue Eosinophilia (TATE) Squamous Cell Carcinoma (SCC)

Growth and Fabrication of GaN/InGaN Violet Light Emitting Diode on Patterned Sapphire Substrate

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Journal of Applied Mathematics and Physics 2014年第12期2卷 1113-1117页

作者： Sonachand Adhikari Saroj Kanta Patra Ashok Lunia Sandeep Kumar Priyavart Parjapat bhoopendra Kushwaha Pawan Kumar Sumitra singh Ashok Chauhan Kuldip singh Suchandan Pal C. Dhanavantri CSIR-Network of Institutes for Solar Energy (CSIR-NISE) CSIR-Central Electronics Engineering Research Institute (CSIR-CEERI) Pilani Rajasthan India Academy of Scientific and Innovative Research (AcSIR) Chennai Tamil Nadu India

GaN/InGaN based violet light emitting diodes (LEDs), emitting at 430 nm, have been grown on conventional single side polished (SSP) and patterned sapphire substrates (PSS). Characteristics of the epitaxial wafers and subsequently fabricated LEDs have been analyzed. The photoluminescence (PL) peaks have been observed at 428.1 nm 426.1 nm for the epitaxial layers on SSP and PSS respectively. The PL intensity is 2.9 times higher in the case of PSS. The electroluminescence (EL) peaks have been observed at 430.78 nm and 430.35 nm for the LEDs on SSP and PSS respectively. The light output from LED fabricated on the PSS is 2.15 times higher than that of the LED on SSP at a forward current of 100 mA.

关键词： LED GaN/InGaN PSS