Transmission electron microscopy (TEM) is a technique where the electron-beam is
transmitted through an ultra-thin specimen, interacting with specimen as it passes
through it. An image is formed from the interaction of the electrons transmitted
through the specimen, which is then magnified and focused onto an imaging device,
such as a fluorescent screen, a photographic film, or a charge-coupled device (CCD)
sensor. This technique is capable of imaging at significantly high resolution than the
light microscopes, owing to the small de-Broglie wavelength of electrons....
Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài: Chemical characterization of extra layers at the interfaces in MOCVD InGaP/GaAs junctions by electron beam methods
Today, an individual would be hard-pressed to find any science field that does not employ methods and instruments based on the use of fine focused electron and ion beams. Well instrumented and supplemented with advanced methods and techniques, SEMs provide possibilities not only of surface imaging but quantitative measurement of object topologies, local electrophysical characteristics of semiconductor structures and performing elemental analysis.
Advances in nanotechnology over the past decade have made scanning electron
microscopy (SEM) an indispensable and powerful tool for analyzing and
constructing new nanomaterials. Development of nanomaterials requires
advanced techniques and skills to attain higher quality images, understand
nanostructures, and improve synthesis strategies. A number of advancements
in SEM such as field emission guns, electron back scatter detection (EBSD),
and X-ray element mapping have improved nanomaterials analysis.
Sensor used in this project is MOC 7811 from
Motorola. This is a slotted coupler/interrupter device.
In each revolution as the beam is interrupted,
the sensor generates a positive pulse. Microcontroller
will execute interrupt routine, When a pulse occurs.
Interrupt routine measures the total time taken for one
revolution, divides it by 120, and stores the result into another
Configured in auto-reload mode.
Now, the timer overflows after tiny intervals of time. Each time it
overflows, next stored value is called from the lookup table,
Electron beam lithography (EBL) là thuật ngữ chỉ công nghệ tạo
các chi tiết trên bề mặt (các phiến Si...) có kích thước và hình dạng
giống như thiết kế bằng cách sử dụng chùm điện tử có
năng lượng cao làm biến đổi các chất cản quang phủ trên bề mặt
EBL là một công cụ phổ biến trong công nghệ nanô để tạo ra các
chi tiết, các linh kiện có kích thước nhỏ với độ chính xác cực cao....
Electrochemistry has been undergoing significant transformations in the last few decades. It is now the province of academics interested only in measuring thermodynamic properties of solutions and of industrialists using electrolysis or manufacturing batteries, with a huge gap between them. It has become clear that these, apparently distinct subjects, alongside others, have a common ground and that they have grown towards each other, particularly as a result of research into the rates of electrochemical processes....
Since its introduction in the early 1970s, computed tomography (CT) has become a
robust modality to evaluate extracranial, thoracic, and abdominal vascular distributions.
It has become a gold standard to non-invasively image the aorta, pulmonary arteries,
great vessels, renal and peripheral arteries. However, cardiac anatomy evaluation with
this modality was not possible, due to rapid cardiac motion and slow image acquisition
Radiotherapy, also referred to as radiation therapy, radiation oncology or
therapeutic radiology, is one of the three principal modalities used in the
treatment of malignant disease (cancer), the other two being surgery and
6.002 Fall 2000
Analytical method Graphical method Today Incremental analysis Reading: Section 4.5
6.002 Fall 2000
.Method 3: Incremental Analysis
Motivation: music over a light beam Can we pull this off?
vI (t ) + –
+ vD LED light intensity I D ∝ iD vI music signal
iR ∝ I R light intensity IR in photoreceiver
LED: Light Emitting expoDweep ☺
vI (t )
iD (t )
iR (t )
6.002 Fall 2000
linear problem! will result in distortion
The World is confronted with a plethora of potentially disruptive technologies
– some, such as nanotechnology, will inevitably challenge our cherished
social, economic and industrial stability over the next two decades. Rational
design and manufacture of materials properties through nanostructure control
will profoundly affect the food we eat, the sources of water and power we
use, our health services, our national security, housing, transportation, etc.
Precisely what will be the ultimate effect of these disruptions is still unclear.
Metal nanoparticles are certain to be the building blocks of the next generation of
electronic, optoelectronic and chemical sensing devices. The physical limits imposed
by top-down methods such as photo- and electron- beam lithography dictate
that the synthesis and assembly of functional nanoscale materials will become
the province of chemists.
Magnesium is the lightest of all the metals and the sixth most abundant on Earth. Magnesium is ductile and the most machinable of all the metals. Magnesium alloy developments have traditionally been driven by requirements for lightweight materials to operate under increasingly demanding conditions (magnesium alloy castings, wrought products, powder metallurgy components, office equipment, nuclear applications, flares, sacrificial anodes for the protection of other metals, flash photography and tools). The biggest potential market for magnesium alloys is in the automotive industry. ...
Tuyển tập các báo cáo nghiên cứu khoa học ngành y học tạp chí Medical Sciences dành cho các bạn sinh viên ngành y tham khảo đề tài: Monte Carlo Commissioning of Low Energy Electron Radiotherapy Beams using NXEGS Software...
Wang et al. Nanoscale Research Letters 2011, 6:367 http://www.nanoscalereslett.com/content/6/1/367
Freestanding HfO2 grating fabricated by fast atom beam etching
Yongjin Wang1,2*, Tong Wu2, Yoshiaki Kanamori2 and Kazuhiro Hane2
Abstract We report here the fabrication of freestanding HfO2 grating by combining fast atom beam etching (FAB) of HfO2 film with dry etching of silicon substrate. HfO2 film is deposited onto silicon substrate by electron beam evaporator.