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Effect of Low-Pressure Nitrogen DC Plasma Treatment on the Surface Properties of Biaxially Oriented Polypropylene, Poly (Methyl Methacrylate) and Polyvinyl Chloride Films

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Plasma Science and Technology 2013年第4期15卷 362-367页

作者： S. Hamideh MORTAZAVI Mahmood GHORANNEVISS Soheil PILEHVAR Sina ESMAEILI shamim ZARGHAM S. Ebrahim HASHEMI Hamzeh JODAT Plasma Physics Research Center Science and Research Branch Islamic Azad University Tehran Iran Polymer Engineering Group Composite Science and Technology Research CenterTehran Iran Plasma Physics Research Center Science and Research Branch Islamic Azad UniversityTehran Iran Polymer Engineering Center Science and Research Branch Islamic Azad UniversityTehran Iran Polymer Engineering Group Composite Science and Technology Research CenterTehran Iran

In this study, commercial biaxially oriented polypropylene （BOPP）, polyvinyl chlo- ride （PVC） and poly （methyl methacrylate）（PMMA） films were treated with nitrogen plasma over different exposure times in a Pyrex tube surrounded by a DC variable magnetic field. The chemi- cal changes that appeared on the surface of the samples were investigated using Fourier transform infrared （FT4R） spectroscopy and attenuated total reflectance Fourier transform infrared （ATR- FTIR） spectroscopy after treatment for 2 min, 4 min and 6 rain in a nitrogen plasma chamber. Effects of the plasma treatment on the surface topographies and contact angles of the untreated and plasma treated films were also analyzed by atomic force microscopy （AFM） and a contact angle measuring system. The results show that the plasma treated films become more hydrophilic with an enhanced wettability due to the formation of some new polar groups on the surface of the treated films. Moreover, at higher exposure times, the total surface energy in all treated films increased while a reduction in contact angle occurred. The behavior of surface roughness in each sample was completely different at higher exposure times.

关键词： plasma surface treatment biaxially oriented polypropylene polyvinyl chlo-ride poly (methyl methacrylate) wettability

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Dielectric relaxation and modulus spectroscopy analysis of(Na_(0.47)K_(0.47)Li_(0.06))NbO_(3) ceramics

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Journal of Advanced Dielectrics 2017年第3期7卷 37-47页

作者： Md Kashif shamim Seema Sharma Sangeeta Sinha Eqra Nasreen Materials Research Laboratory Department of Physics A.N.College Patna 800013India Department of Environmental Science A.N.College Patna 800013India

We have investigated the structure,dielectric and electrical properties of lead-free polycrystalline (Na_(0.47)K_(0.47)Li_(0.06))NbO_(3) ceramics as a function of temperature and frequency in order to understand the intrinsic contribution of grain/bulk and grain boundary effects toward the dielectric response as well as the electrical conduction mechanism in the samples fabricated by microwave sintering method.X-ray diffraction analysis exhibits perovskite structure with orthorhombic symmetry,which is well supported by the Raman spectroscopic analysis.A minor secondary impurity phase of tungsten bronze structure was observed for samples sintered at 1050℃,which gets weaker for samples sintered at 1150℃.Dielectric permittivity was enhanced by 50%,although there was a reduction in the dielectric loss by about 50%at Curie temperature(450℃)for samples sintered at 1150℃.Complex impedance spectroscopic analysis indicated non-Debye-type dielectric relaxation present in the samples,and this phenomenon followed thermally activated process related to hopping *** plot showed the negative temperature coefficient of resistance,characteristic of the samples.

关键词： Lead-free piezo-ceramics dielectric properties AC impedance spectroscopy dielectric relaxation negative temperature coefficient of resistance(NTCR).

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Geochemistry of sedimentary rocks from Permian–Triassic boundary sections of Tethys Himalaya: implications for paleo-weathering, provenance, and tectonic setting

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Acta Geochimica 2016年第4期35卷 428-436页

作者： Akhtar R.Mir V.Balaram Javid A.Ganai shamim A.Dar A.Keshav Krishna Department of Earth Sciences University of KashmirSrinagar 190006India CSIR-National Geophysical Research Institute Hyderabad 500007India Department of Geology S.P.CollegeSrinagar 190008India

The geochemical characteristics of two sections—the Permian–Triassic boundary(PTB) Guryul Ravine section, Kashmir Valley, Jammu and Kashmir,India; and the Attargoo section, Spiti Valley, Himachal Pradesh, India—have been studied in the context of provenance, paleo-weathering, and plate tectonic *** sections represent the siliciclastic sedimentary sequence from the Tethys Himalaya. The PTB siliciclastic sedimentary sequence in these regions primarily consists of sandstones and shales with variable thickness. Present studied sandstones and shales of both sections had chemical index of alteration values between 65 and 74; such values reveal low-to-moderate degree of chemical weathering. The chemical index of weathering in studied samples ranged from 71 to 94, suggesting a minor K-metasomatism effect on these samples. Plagioclase index of alteration in studied sections ranged from 68 to 92, indicating a moderate degree of weathering of plagioclase feldspars. The provenance discriminant function diagram suggests that the detritus involved in the formation of present studied siliciclastic sedimentary rocks fall in quartzose sedimentary and felsic igneous provenances. These sediments were deposited in a passive continental margin plate tectonic setting according to their location on a Si_2 O versus K_2O/Na_2 O tectonic setting diagram.

关键词： Geochemistry Permian-Triassic boundary - Guryul Ravine Tectonic settings

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Human leukocyte antigen B polymorphism and association between HLA-B27 and endoplasmic reticulum aminopeptidase 1 rs30187 SNP in patients with ankylosing spondylitis in Bangladesh

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Rheumatology & Autoimmunity 2022年第1期2卷 15-21页

作者： Md Kamrul H.Sajib shamim Ahmed Syed A.Haq Minhaj R.Choudhury Mohammed uddin Furkan uddin Muhammad S.A.Khan Mohammad M.Zaman Department of Rheumatology Dhaka Medical College HospitalDhakaBangladesh Department of Rheumatology Bangabandhu Sheikh Mujib Medical UnivesityDhakaBangladesh Department of Human Genetics Mohammed Bin Rashid University of Medicine and Health SciencesCollege of MedicineDubaiUAE Genetics and Genomic Department NeuroGen HealthcareDhakaBangladesh Department of Medicine Sheikh Hasina Institute of Burn and Plastic SurgeryDhakaBangladesh Advisor(Research and Publication) World Health OrganizationDhakaBangladesh

Objectives:To determine the association of Human leukocyte antigen B(HLA‑B)alleles with ankylosing spondylitis and the allelic association of HLAB27 with endoplasmic reticulum aminopeptidase 1(ERAP1)single-nucleotide polymorphism(SNP)rs30187 in patients with ankylosing spondylitis(AS).Methods:We studied 48 consecutively enrolled well-defined AS patients and 48 healthy controls recruited from the outpatient clinic of the rheumatology department of Bangabandhu Sheikh Mujib Medical University(BSMMU),Dhaka,*** genotype HLA-B alleles from peripheral blood DNA,we designed sequence-specific primers for polymerase chain ***'s sequencing method was used to detect the ERAP1 rs30187 *** HLA-B allele distributions were compared between cases and *** infer an allelic association between HLA-B27 and ERAP1,allele distributions from both loci were compared using ***-squared test or Fisher's exact test was used to quantify the association,and their strength of association was tested by odds ratio(OR)with 95%confidence interval(CI).Results:The frequency of HLA-B27 was found to be higher in AS patients(60.4%)than in healthy controls(8.3%).HLA-B27 allele had an OR of 16.8(95%CI=5.2–54.4)for the development of ***,4%of AS patients had both HLA-B27 and *** significant association was found between ERAP1 rs30187 SNP and HLA-B27 in patients with AS(OR=1.7,95%CI=0.5–5.6).Conclusions:HLA-B27 was significantly associated with AS in patients in ***,no association between ERAP1 rs30187 SNP and HLA-B27 was observed.

关键词： AS Bangladesh ERAP1 rs30187 SNP HLA-B HLA-B27

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Design and Numerical Analysis of Ultra-High Negative Dispersion, Highly Birefringent Nonlinear Single Mode Core-Tune Photonic Crystal Fiber (CT-PCF) over Communication Bands

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Optics and Photonics Journal 2023年第10期13卷 227-242页

作者： Amit Halder Wahiduzzaman Emon Md. shamim Anower Md. Riyad Tanshen Md. Forkan Md. Sharif uddin Shajib Department of Electrical and Electronic Engineering World University of Bangladesh Dhaka Bangladesh Department of Electrical and Electronic Engineering Rajshahi University of Engineering and Technology (RUET) Rajshahi Bangladesh Department of Electrical and Electronic Engineering Ahsanullah University of Science and Technology (AUST) Dhaka Bangladesh

This paper presents the development of a highly efficient CT-PCF (Core-Tune Photonic Crystal Fiber) with substantial birefringence, tailored for applications in high-bit-rate communication and sensing while minimizing signal loss. The design incorporates a modified broadband dispersion compensating structure, optimized for operation across the E, S, C, and L communication bands within a wavelength range spanning 1360 nm to 1625 nm. Notably, the CT-PCF demonstrates a remarkable birefringence of 2.372 × 10-2 at 1550 nm, surpassing traditional PCF structures. Single-mode performance is evaluated using the Higher Order Mode Extinction Ratio (HOMER) method, revealing a peak HOMER value of 104 at 1550 nm. Furthermore, at 1550 nm, the CT-PCF exhibits exceptional nonlinear characteristics, featuring a high nonlinearity of 50.74 W-1⋅Km-1 for y polarization. In comparison to existing designs, the proposed CT-PCF exhibits superior performance metrics and optical characteristics. Additionally, the y polarization dispersion coefficient of the CT-PCF at 1550 nm is measured at -3534 ps/(nm⋅km). Overall, the CT-PCF represents a significant advancement, outperforming established systems in terms of performance metrics and optical properties.

关键词： Negative Dispersion Birefringence Confinement Loss HOMER Method Single-Mode Performance Optical Properties

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Vehicle fuel from biogas with carbon membranes; a comparison between simulation predictions and actual field demonstration

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Green Energy & Environment 2018年第3期3卷 266-276页

作者： shamim Haider Arne Lindbrathen Jon Arvid Lie Petter Vattekar Carstensen ThorbjØrn Johannessen May-Britt Hagg Norwegian University of Science and Technology NTNUDepartment of Chemical Engineering

The energy contents of biogas could be significantly enhanced by upgrading it to vehicle fuel quality.A pilot-scale separation plant based on carbon hollow fiber membranes for upgrading biogas to vehicle fuel quality was constructed and operated at the biogas plant,Gl?r IKS,Lillehammer *** fuel quality according to Swedish legislation was successfully achieved in a single stage separation *** raw biogas from anaerobic digestion of food waste contained 64±3 mol%CH_4,30–35 mol%CO_2 and less than one percent of N_2 and a minor amount of other *** raw biogas was available at 1.03 bar with a maximum flow rate of 60 Nm^3h^(à1).Pre-treatment of biogas was performed to remove bulk H_2O and H_2S contents up to the required limits in the vehicle fuel before entering to membrane *** membrane separation plant was designed to process 60 Nm^3h^(à1)of raw biogas at pressure up to 21 *** initial tests were,however,performed for the feed flow rate of 10 Nm^3h^(à1)at 21 *** successful operation of the pilot plant separation was continuously run for 192 h(8days).The CH_4 purity of 96%and maximum CH_4 recovery of 98%was reached in a short-term test of 5 *** permeate stream contained over20 mol%CH_4which could be used for the heating *** Hysys~?was integrated with Chem Brane(in-house developed membrane model)to run the simulations for estimation of membrane area and energy requirement of the pilot *** estimation was performed based on simulation data and later compared with actual field results.

关键词： Biogas upgrading Pilot-scale demonstration Membrane separation Process simulations

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A monodisperse-aerosol generation system： Design, fabrication and performance

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Particuology 2017年第5期15卷 118-125页

作者： Amit Md. Estiaque Arefin M.H. Masud Mohammad U.H. Joardder Md. shamim Akhter Department of Mechanical Engineering Rajshahi University of Engineering and Technology Rajshahi Bangladesh

Monodisperse aerosols are essential in many applications, such as filter testing, aerosol instrument calibration, and experiments for validating models. This paper describes the design principle, construction, and performance of a monodisperse-aerosol generation system that comprises an atomizer, virtual impactor, microcontroller-based isokinetic probe, wind tunnel, and velocity measurement device. The size distribution of the produced monodisperse aerosols was determined by an optical particle counter. The effects of atomizer characteristics, the rates of minor and major flow, and solution criteria were investigated. It was found that all these parameters affect the generation of monodisperse aerosol. Finally, the expected geometric standard deviation （〈1.25） of monodisperse aerosol particles was obtained with the most suitable atomizer for 10% oleic acid in ethyl alcohol solution with 5%-15% minor flow, where the ratio between the nozzle-to-probe distance and acceleration-nozzle-exit diameter was 0.66. The con- structed monodisperse-aerosol-generation system can be used for instrumental calibration and aerosol research.

关键词： Aerosol generation Monodisperse Design Sampling Counting

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Laparoscopic retrieval of two intragastric spoons at least seven years after ingestion

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Laparoscopic, Endoscopic and Robotic Surgery 2019年第3期2卷 77-79页

作者： Adeel Ahmed shamim Muhammad Maaz Zuberi Amir Hafeez Shariff Department of General Surgery Howard University HospitalWashington DC20060USA Department of General Surgery Aga Khan University HospitalKarachi74800Pakistan

Foreign body ingestion is a commonly encountered *** majority of foreign bodies pass in stool spontaneously within one week or are managed endoscopically within the first 24e48 *** guidelines are available for management of chronically retained foreign bodies at present.A unique case is presented of two chronically retained teaspoons in the stomach that failed endoscopic retrieval and required laparoscopic *** operatively,the patient did well with no complications.A large foreign body that is not amenable to endoscopic intervention will benefit from *** expertise is available,laparoscopic intervention is a safe and feasible option to remove large foreign bodies from the stomach that is not amenable to endoscopic retrieval.

关键词： Endoscopy Large foreign body ingestion Laparoscopic retrieval

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Pembrolizumab-emerging treatment of pulmonary sarcomatoid carcinoma: A case report

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World Journal of Clinical Cases 2020年第1期8卷 97-102页

作者： Emanuela Cimpeanu Jibran Ahmed Wahib Zafar Adreana DeMarinis Svetoslav S Bardarov shamim Salman Dennis Bloomfield Department of Internal Medicine Richmond University Medical CenterStaten IslandNY 10310United States Department of Hematology and Medical Oncology Westchester Medical CenterValhallaNY 10595United States Department of Pathology Richmond University Medical CenterStaten IslandNY 10310United States Department of Hematology and Medical Oncology Richmond University Medical CenterStaten IslandNY 10310United States Department of Clinical Research Richmond University Medical CenterStaten IslandNY 10310United States

BACKGROUND Few studies have addressed the efficacy of pembrolizumab in pulmonary sarcomatoid carcinoma(PSC),a rare,previously rapidly fatal subtype of nonsmall-cell lung *** SUMMARY We report the case of a 69-year-old man presented with respiratory distress caused by a large left upper lung lobe mass diagnosed as PSC with programmed death-ligand 1 expressed on more than 50 percent of tumor *** patient was started on pembrolizumab and,after 5 cycles,there was a more than 80 percent decrease in the size of the tumor *** decrease was seen at the end of 10 *** patient has been tolerating pembrolizumab well,with no limiting *** months after first coming into the hospital,he remains *** Pembrolizumab appears as a viable emerging treatment for PSC.

关键词： Pembrolizumab Pulmonary sarcomatoid carcinoma Programmed deathligand 1 Platinum-based chemotherapy Non-small-cell lung cancer Overall survival Case report

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Laparoscopic reduction and repair of acute traumatic diaphragmatic hernia:A video review

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Laparoscopic, Endoscopic and Robotic Surgery 2020年第1期3卷 22-25页

作者： Adeel Ahmed shamim Muhammad Maaz Zuberi Daniel Tran Terrance Fullum Department of General Surgery Howard University Hospital2041 Georgia Ave NWWashingtonDC20060USA

Traumatic diaphragmatic hernia is one of the sequela of thoraco-abdominal injury,occurring in about 0.5%-5% of patients presenting post major *** vehicle collision is the leading blunt trauma etiology.A high level of suspicion is essential to discover such injuries,as a majority of the patients can be asymptomatic.A case of a successful trans-abdominal laparoscopic reduction and repair of a large acute traumatic diaphragmatic hernia is presented as a video *** were able to evacuate all intrathoracic air,obliviating the need for a chest *** operatively the patient did well with no *** expertise is available,laparoscopic intervention is a feasible option even for large traumatic diaphragmatic hernia preventing the need for a large midline laparotomy incision.

关键词： Laparoscopy Diaphragm Traumatic diaphragmatic hernia Hernia Thoracoabdominal trauma Video

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