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Microstructural aspects of in-situ TiB reinforced Ti-6Al-4V composite processed by spark plasma sintering

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Transactions of Nonferrous Metals Society of China 2015年第5期25卷 1460-1467页

作者： saeid GHESMATI TABRIZI Abolfazl BABAKHANI Seyed Abdolkarim SAJJADI 吕维洁 Department of Materials Science and Engineering Engineering Faculty Ferdowsi University of Mashhad 上海交通大学材料科学与工程学院金属基复合材料国家重点实验室上海200240

Titanium-matrix composites have important and wide applications in the transport and aerospace industries. The current research was focused on powder metallurgy processing of in-situ reinforced titanium-matrix composite with Ti B whiskers. The Ti-6Al-4V alloy and B4 C additive powders were used as raw materials. Two different consolidation techniques, namely press-and-sintering and spark plasma sintering, were selected. It was observed that in-situ Ti B whiskers were formed during sintering in both methods. The changes in size, aspect ratio and distribution of in-situ whiskers in different composite samples were monitored. The effect of spark plasma sintering temperature on the synthesis of in-situ whiskers was also investigated. Based on the microstructural observations（optical microscopy and scanning electron microscopy） and the energy dispersive spectroscopy analysis, it was concluded that increasing the spark plasma sintering temperature from 900 to 1100 °C would lead to the complete formation of in-situ Ti B whiskers and reduced porosity content.

关键词： Ti-6Al-4V metal matrix composite TiB whisker in-situ reaction spark plasma sintering

Experimental Optimization of the Output Power of a Copper Vapor Laser Using Air as a Buffer Gas

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Optics and Photonics Journal 2016年第4期6卷 53-59页

作者： Mahboobeh Mirzaei saeid Behrouzinia Masoud Sabaghi saeid Marjani Kamran Khorasani Batool Sajad Department of Physics Alzahra University Tehran Iran Laser and Optics Research School Nuclear Science and Technology Research School Atomic Energy Organization of Iran Tehran Iran Department of Electrical Engineering Ferdowsi University of Mashhad Mashhad Iran

In order to investigate the effect of the pressure buffer gas and frequency on the output power, a copper vapor laser with active medium length of 60 cm and bore of 16 mm has been operated and optimized using air as a buffer gas. The observed oscillatory behavior of the output power versus frequency is in good agreement with the previous reports. The measured results show the maximum output power of ~1.6W at the optimum pressure of 3.8 torr and frequency of 17 kHz. Abundance of the air and reduction of the system volume due to elimination of the gas handling system as well as the economically benefits are the advantages of the employing air as a buffer gas in the copper vapor laser operation.

关键词： Experimental Optimization Copper Vapor Laser Air Buffer Gas

Prevalence of smoking among universities students of Shahroud in 2010

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Open Journal of Preventive Medicine 2012年第2期2卷 235-239页

作者： saeid Nazemi Reza Chaman Department of Basic Sciences School of Medicine Shahroud University of Medical Science Shahroud Ian Department of Environmental Health Faculty of Health Shahroud University of Medical Science Shahroud Iran

This study in 2010 determined the prevalence of smoking and its associated factors among universities students in Shahroud located in the North Eastern of Iran. 1800 students were selected randomly among 20000 students of Shahroud universities, to complete a questionnaire Which was prepared based on the Global Youth Tobacco Survey. The prevalence of current smoking was 20% (80% male and 20% female). The most important factors in the tendency to smoking were: friends smoking, stress, separation from family and fun.

关键词： Prevalence Smoking Students Shahroud Insert

Protein biomarkers of neural system

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Journal of Otology 2019年第3期14卷 77-88页

作者： Fatemeh Ghanavatinejad Zahra Pourteymour Fard Tabrizi Shadi Omidghaemi Esmaeel Sharifi Simon Geir Moller Mohammad-saeid Jami Cellular and Molecular Research Center Basic Health Sciences Institute Shahrekord University of Medical Science Shahrekord Iran Department of Tissue Engineering and Biomaterials School of Advanced Medical Sciences and Technologies Hamadan University of Medical Sciences Hamadan Iran Department of Biological Sciences St John's University New York NY USA The Norwegian Centre for Movement Disorders Stavanger University Hospital Norway Department of Neurology David Geffen School of Medicine University of California Los Angeles CA 90095 USA

The utilization of biomarkers for in vivo and in vitro research is growing rapidly. This is mainly due to the enormous potential of biomarkers in evaluating molecular and cellular abnormalities in cell models and in tissue, and evaluating drug responses and the effectiveness of therapeutic intervention strategies. An important way to analyze the development of the human body is to assess molecular markers in embryonic specialized cells, which include the ectoderm, mesoderm, and endoderm. Neuronal development is controlled through the gene networks in the neural crest and neural tube, both components of the ectoderm. The neural crest differentiates into several different tissues including, but not limited to, the peripheral nervous system, enteric nervous system, melanocyte, and the dental pulp. The neural tube eventually converts to the central nervous system. This review provides an overview of the differentiation of the ectoderm to a fully functioning nervous system, focusing on molecular biomarkers that emerge at each stage of the cellular specialization from multipotent stem cells to completely differentiated cells. Particularly, the otic placode is the origin of most of the inner ear cell types such as neurons, sensory hair cells, and supporting cells. During the development, different auditory cell types can be distinguished by the expression of the neurogenin differentiation factor1 (Neuro D1), Brn3a, and transcription factor GATA3. However, the mature auditory neurons express other markers including bIII tubulin, the vesicular glutamate transporter (VGLUT1), the tyrosine receptor kinase B and C (Trk B, C), BDNF, neurotrophin 3 (NT3), Calretinin, etc.

关键词： Neural system Biomarker Differentiation Stem cell Nervous system Otic placode

Human Health Risk Assessment in Shahid Rajaee Container Terminal

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Open Journal of Ecology 2016年第11期6卷 686-698页

作者： Abdollah Jafari saeid Givehchi Mahnaz Nasrabadi Department of Environment Management (HSE) Faculty of Engineering and Technology Zahedan Branch Islamic Azad University Zahedan Iran Faculty of Environment University of Tehran Tehran Iran

As the ports play a prominent role in the national economy of the countries and a number of factors such as safety condition of the port and low rate or non-occurrence of accidents are greatly important for being selected as a destination for cargo owners to bring their vessels and cargo therein, giving due care to safety related issues in ports and harbors is among jurisdictional and sensitive duties of the authorities in ports and maritime areas. Enjoying some 3000 km of marine coastlines and more than 10 commercial ports throughout the country, Iran is no exception where its ports are responsible for cargo import and export. In this respect, container terminals are one of the high-risk areas in ports requiring extensive care of the pertaining authorities to take appropriate measures to maintain safety standard there. One of the significant methods and techniques for the risk assessment is P&HRAM as to the containers terminals. This method has been employed in this research taking into account the operation attributes of the works in ports and harbors. This method provided appropriate answers to the research questions in that it was predicted that the great part of the activities in container terminal poses a higher risk from human perspective than expected requiring some measures to be taken to mitigate the risks to a tolerable level. This research was conducted and the results demonstrated that more than 75% of the risks in container terminals are higher than acceptable level about which some measures were taken and the risks were reduced to 100% lower than tolerable level.

关键词： Human Risks Container Terminal Safety Management

VLSI and SPICE modeling of ALU

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通讯和计算机（中英文版） 2009年第10期6卷 44-53页

作者： saeid Mos lehpour Srikrishna Karatalapu Department of Electrical and Computer Engineering University of Hartford West Hartford CT 06117 USA

The Arithmetic and Logic Unit (ALU) is a combination circuit that performs a number of arithmetic and logical operations within a microprocessor. The demand for faster and compact ALUs makes it desirable to test the ALU in conjunction with pre-design parts prior to manufacture. This may be accomplished in a process using CAD and SPICE simulation software. Our purpose is to realize a method for importing a layout drawn in Tanner L-edit and simulated in T-Spice into PSpice which is referred to as software talking. To do so we use an eight-function instruction set called Complimentary Metal Oxide Semiconductor Arithmetic and Logic Unit (CMOS ALU) which is laid out in Tanner L-edit and produces an extracted net-list which is simulated in T-Spice. An ALU equivalent design is then modeled in PSpice for further testing with pre-manufactured parts of the PSpice library.

关键词： SPICE 超大规模集成电路 ALU 建模互补金属氧化物半导体 PSpice 逻辑单元仿真软件

The Surface Plasmons＇ Frequencies of Two Adjacent Metallic Nanospheres by Bloch-Jensen Hydrodynamical Model

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Journal of Physical Science and Application 2013年第1期3卷 54-57页

作者： Moslem Mirasmouri saeid Rostami Department of Physics Faculty of Science University of Zabol Zabo198615-538 Iran Department of Physics Faculty of Science Yazd University Yazd 89195-741 Iran

The wave guides and optical fibers have long been known to transmit light and electromagnetic fields in large dimensions. Recently, surface plasmons, which are collective plasma oscillations of valence electrons at metal surfaces, have been introduced as an entity that is able to guide light on the surfaces of the metal and to concentrate light in subwavelength volumes. It has been found that periodic array of metallic nanospheres, could be able to enhance the light transmission, and guiding light at nanoscale. The coupling between two nanoparticles in these devices is very important. The Bloch-Jensen hydrodynamical method has been used for computing surface plasmons＇ frequencies of a single metallic nanosphere. It contains the entire pole spectrum automatically, so it is more exactly than the other computational methods. In this research, we have computed the surface plasmons＇ frequencies of two adjacent nanospheres by Bloch-Jensen hydrodynamical model for the first time. The results show that there are two modes for this system, which depend explicitly on interparticle spacing. In addition, we have shown that the excitation modes yield to a single mode of a nanoparticle as the interparticle spacing increases.

关键词： Surface plasmons plasmon-polaritons nanoparticles nanophotonics.

A Low Phase Noise, Low Power and Wide Tuning Range VCO with Filtering Technique in ISM Band

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Circuits and Systems 2016年第2期7卷 51-57页

作者： Masoud Sabaghi saeid Marjani Abbas Majdabadi Laser and Optics Research School Nuclear Science and Technology Research School Atomic Energy Organization of Iran Tehran Iran Department of Electrical Engineering Ferdowsi University of Mashhad Mashhad Iran

In this paper, a novel voltage controlled oscillator (VCO) with low phase noise, low power consumption and wide tuning range in the industrial, scientific and medical (ISM) band is proposed for communication systems applications. For improving the phase noise, filtering technique is used and VCO is designed with TSMC CMOS 0.18 μm technology and the power supply is 1.5 V. The simulation results with advanced design system (ADS) shows that phase noise in 1 MHz offset frequency from the carrier is -122 dBc/Hz and tuning range is 2 to 2.8 GHz. The power consumption of the core is 2.49 mW.

关键词： Filtering Technique Tuning Range Phase Noise Power Consumption Voltage Controlled Oscillators (VCO)

The Design of Ultra-Low Power Adder Cell in 90 and 180 nm CMOS Technology

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Circuits and Systems 2016年第2期7卷 58-67页

In this paper, an ultra-low power adder cell is proposed. With cascading two XNOR cells, the sum of two inputs is achieved. Regarding to advantages of m-GDI XNOR cell, we constructed the adder cell based on this architecture. The simulation results show that the power consumption of the adder cell designed with GDI technology is 12.993 μw, whereas for this cell designed with m-GDI technology is 4.1628 μw, which both are designed at 0.18 um technology. Moreover, simulation results in 90 nm CMOS technology for m-GDI adder cell show average power consumption of 0.90262 μw and 6.3222 μw in 200 MHz and 2GHz, respectively.

关键词： Adder Cell Gate-Diffusion-Input (GDI) Bit-Serial Adder