Nuclear Medicine

The most important breakdown in the public’s understanding of nuclear power is in its concept of the dangers of radiation. Radiation consists of several types of subatomic particles, principally those called gamma rays, neutrons, electrons, and alpha particles. These particles shoot through space at very high speeds, something like 100,000 miles per second and they can easily penetrate deep inside the human body, damaging some of the biological cells of which the body is composed. This damage can cause a fatal cancer to develop, or if it occurs in reproductive cells, it can cause genetic defects in later generations of offspring.

However, through constant development in medical and nuclear science, especially in particle physics, scientists have come up with a revolutionary concept in using radiation as a mean of diagnosing and curing diseases. This in every way contradicts the basic understanding among people regarding radiation. In the medical field, scientists have been toiling endlessly to understand the behavior of radiation particles or to be more precise ionizing radiation. Once the secret of ionizing radiation is fully understood, it breaks open a whole new possibility and potential for nuclear medicine using radioactive substance.

So what exactly is nuclear medicine? Nuclear medicine uses radioactive substance which gives off ionizing radiation as they decay, to both diagnose and treat diseases. To put this subject into retrospective, in medical diagnostics using nuclear scans, a radioactive substance is injected, swallowed or breathed into the body and it gives off radiation (gamma rays) as it passes through or lodges in the body. These invisible rays can be tracked and used to produce images and doctors will then check the pictures to find for lumps or tumors as well as cancerous cells. Scans are the main use of nuclear medicine.

In treating diseases, radiotherapy is considered one of the best methods of combating cancer cells from spreading. Radioactive substance is able to stop cancers growing, and destroys cancer cells. It can be used to cure cancers or to ease a patient’s suffering. For example, thyroid cancers are treated by swallowing radioactive iodine. Doctors administer treatment using nuclear medicine because radiation damages cancer cells more than is harms normal cells. For example, heart and blood vessel examinations can be done with a thallium stress test .The thallium isotope is produced in a cyclotron, a type of particle accelerator. Iodine 123, which is primarily used to generate images of the thyroid, is also produced in a cyclotron.

The Medical Cyclotron

The cyclotron is an accelerator of subatomic particles. It produces a large quantity of protons (heavy particles with an electrical positive charge) and gets them moving at an accelerated rate along a circular orbit, inside a chamber controlled by powerful alternating electromagnetic fields. Thus, the particles gain energy and are smashed against a target at nearly the speed of light. The isotopes produced by the cyclotron are used for body imaging.

The Medical Cyclotron structural layout.

However, there is the common misconception that X-rays and CT Scans are classified as nuclear medicine. This is not true because they are not produced from radioactive substance. X-ray images, used to diagnose disease, are similar to photographs. A normal camera records light bouncing off the surface of objects and transmits it into the camera. Because X-rays penetrate into softer objects (like bodies, or luggage), we can use them with a special camera to make pictures of the harder objects inside our bodies or our backpacks: lumps, bones, metal. X-rays are also used in curing cancers, by focusing concentrated X-Rayson the cancer site. X-rays, however, are a type of ionizing radiation. CT Scans, like X-Rays, are not classified as nuclear medicine. CT Scans use many X-Rays to create a 3-dimensional picture. They are a greater concern as the risk of cancer for the patient is greater for Cat Scans than for X-Rays.

References:

http://nuclear-news.net/information/wastes-2/draft-august-2/

http://www.lbl.gov/Publications/Currents/Archive/Aug-27-1999.html

http://www.cerebromente.org.br/n01/pet/petcyclo.htm

Survey Result

PART A

PART B

Visit from a World Renowned Quantum Science and Engineering Researcher: Prof Dr Michihiro Furusaka

On the 8th of December 2011, Uniten was fortunate enough to be graced by the presence of Prof Michihiro Furusaka,Phd. He is a professor at the Graduate School of Engineering at Hokkaido University, Japan, working in the field of neutron instrumentation and optics. Currently, he is developing a new mini-focusing small angle neutron scattering (mfSANS) instrument.

He came to Uniten to conduct a lecture on quantum beam technology and its application in various fields including nuclear engineering.This was all made posible by Nuclear Malaysia.

In many applications such as fuel cells, batteries and superconductors, most of the key properties are linked to the nanostructure of their constituent materials. Any attempt at the tuning of this nanostructure in order to optimize the application properties, however, requires the ability to extract the morphological details on length scales ranging from the sub-nm scale up to the micron scale. Moreover, since the application properties are defined by the average of the bulk material, the statistically representative characterization of the average nanostructure is a necessity.

Small-angle scattering (of light, X-rays, and neutrons) is a unique nanostructural characterization technique capable of obtaining exactly this; providing average morphological parameters over volumes ranging from cubic micrometers to cubic centimeters. The widespread adoption of this technique, however, has been hindered by a complicated data interpretation as well as instrumental limitations.

He started of the lecture by giving a brief overview of the current situation  in large neutron facilities. He also said that Small Angle Neutron Scattering instrument (SANS) are huge and expensive.Mantaining a Neutron facility is expensive and not always available in developing countries. The instruments also requires lot of manpower and budget to mantain.

SANS machine

Research activities using neutron scattering techniques are strongly hampered by its limited machine-time availability. We need very large facilities, either a research reactor or an accelerator driven neutron source, and the number of such facilities all over the world is rather limited. Also true is the number of instruments at such facilities. As a result, getting machine time of one of such instruments is also severely limited; often they are oversubscribed by a factor of three or more.

In case of X-ray, there are a lot of laboratory based X-ray instruments all over the place. Instruments are commercially available; researchers can test their ideas or new samples without writing a proposal; many researchers know how to analyze data. If you need a more powerful instrument, synchrotron radiation facilities are there.

One way of overcoming this situation around neutron scattering technique, especially for SANS instrument, would be to develop a compact unit instrument that can be installed many on a beamline. The unit should be of low cost and can also be installed at low power accelerator based neutron sources. The answer to this is the mfSANS instrument. By using a neutron-focusing technique, like an ellipsoidal mirror developed, a very compact SANS instrument was made. Current ones are 2.5 and 4m in total lengths. Many devices have to be developed, such as high intensity monochromator, beam branching device, high quality focusing mirror, and detector with high-resolution high-count-rate /highdetecting efficiency. Also important is to develop easy to use software.

The instrument was installed not at horizontal plane, but tilted by 45 degrees toward ceiling from the horizontal line.

The LPSD was installed just in front of the zinc-sulfide scintillation detector as shown

Prof Dr Michihiro FuRUSAKA successfully obtained about 2.5 mm FWHM focused beam at the detector position using a 2 mm aperture at one of the two focal points of the focusing mirror. SANS data was obtained from standard samples, such as Ni powder of 20 nm in diameter and micro-separated block-copolymer DI33.

He highlighted the issues of SANS for low power reactors; which is the efficiency of conversing collimator and loosely focused beam. The possible solutions proposed are converging multi-holes collimator from a bigger sample, and utilizing loosely focused beam by focusing mirrors.

Futhermore, Prof Dr Michihiro Furusaka also explained about the situation of nuclear scattering and proton particle beam accelerators in Malaysia.The lecture was cut short due to time constraints,but it was a very informative and eye opening lecture about quantum beam technology and its role in nuclear engineering.

(ALL THE PICTURES ABOVE ARE CREDITED TO THE WORK OF PROF DR MICHIHIRO FURUSAKA)

“Nuclear option still on the table”-says Prime Minister of Malaysia,Dato’ Seri Najib

 

KUALA LUMPUR: Japan’s Fukushima nuclear reactor disaster has not deterred the Malaysian government from continuing to pursue a nuclear energy plan.

Prime Minister Najib Tun Razak said that the government was in the midst of analysing Malaysia’s suitability for nuclear energy.

“We’re still studying nuclear energy as an option for the generation of electricity, while taking into consideration the instability of the Japanese nuclear reactor caused by a recent earthquake,” said Najib said in a written response in Parliament.

“The government is analysing short and long-term plans, taking into account all infrastructural aspects recommended by the IAEA (International Atomic Energy Agency).”

He was responding to a question posed by Hee Loy Sian (PKR-PJ Selatan) who asked if the government would abandon its plans to build a nuclear reactor in light of the Fukushima disaster.

In mid-March, the Fukushima Daiichi nuclear power plant was damaged when an earthquake and subsequent tsunami rocked eastern Japan.

Several nuclear reactors at the plant experienced a full meltdown, which led the Japanese government to initiate massive evacuation and cleanup efforts.

Nuclear plants by 2021

The cleanup efforts are still ongoing, with nuclear experts trying to contain the situation from deteriorating further.

Several developed countries, including Switzerland and Germany, have since announced plans to withdraw from using nuclear energy.

Malaysia, however, appears to have no such reservations. Najib said that many nuclear energy-using countries around the world were running stress tests on their reactors in light of Fukushima.

He said that Malaysia’s “relevant government agencies” would be studying the stress tests on these reactors, and using them as studies for considering nuclear energy in the country.

He added that other studies, including looking into suitable reactor sites, were being considered.

The government intends to build two 1,000-megawatt nuclear power plants by 2021, under its Economic Transformation Programme (ETP).

Germany and the nuclear power

To understand why the Germany became the first develop country to take action and start shouting down the nuclear program they have, we have to take a look on the history of nuclear in Germany. We all know until 1989 there was two Germanys the east and the west.

West Germany:

The nuclear program start at 1950s, however the first reactor opened in 1960 in Kohl am Main and it was an experimental nuclear power station. All of the German nuclear power plants that opened between 1960 and 1970 had a power output of less than 1,000 MW and have now all closed down. The first commercial nuclear power plant started operating in 1969. Obrigheim, the first grid station, operated until 2005. (Neckarwestheim). A closed nuclear fuel cycle was planned, starting with mining processes in the Saarland and the Schwarzwald; uranium ore concentration, fuel rod filling production in Hanau; and reprocessing of the spent fuel in the never-built nuclear fuel reprocessing plant at Wackersdorf. The radioactive waste was intended to be stored in a deep geological repository, as part of the Gorleben long-term storage project.

East Germany:

The first nuclear power plant in East Germany was Rheinsberg Nuclear Power Plant and they shutdown in 1990. The second to be commissioned, the Greifswald Nuclear Power Plant, was planned to house eight of the Russian 440 MW VVER-440 reactors. The first four went online between 1973 and 1979. The other four were cancelled during different stages of their build-up. In 1990, during the German reunification, all nuclear power plants were closed due to the differences in safety standards. The Stendal Nuclear Power Plant, which was under construction at the time, was cancelled.

Also Germany had three accidents. The first was in 7/12/1975 the locution was Greifswald, East Germany. Electrical error causes fire in the main trough that destroys control lines and five main coolant pumps, almost inducing meltdown. The second was in 4/5/1986 in Hamm-Uentrop. Operator actions to dislodge damaged fuel rod at Experimental High Temperature Gas Reactor release excessive radiation to 4 km2 (1.5 sq mi) surrounding the facility. The third was in 17/12/1987 in Hesse. Stop valve fails at Biblis Nuclear Power Plant and contaminates local area.

In 8/3/2011 the Germany government shutdown 8 nuclear plant in plan to take the nuclear power aout of the picture completely in 2022.Befor they shut down the plants the nuclear power was accounted for 23% of national electricity consumption. The announcement of the plan  was first made by Norbert Röttgen, head of the Federal Ministry for Environment, Nature Conservation and Nuclear Safety, after late-night talks.

 

 

Reference:

http://en.wikipedia.org/wiki/Nuclear_power_in_Germany

 

The IAEA publishes a report on Fukushima’s Nuclear Disaster

The International Atomic Energy Agency (IAEA) has published a preliminary
summary of their fact-finding mission to three nuclear power stations affected
by the earthquake and subsequent tsunami. The original document can be found here.

Some of the key findings include:

• “Hydrogen risks should be subject to detailed evaluation and necessary mitigation systems provided.”This refers to how it is believed that hydrogen entered Unit 4, which has experienced spent fuel pool heating, but was on shutdown for maintenance at the time of the incident. It is now believed that ductwork shared between Units 3 & 4 provided a pathway for hydrogen generated by Unit 3 to enter Unit 4 and reach dangerous levels. This means that this possibility must be investigated in other plants that share these design aspects, and sytems to vent any buildup of hydrogen must be devised. The hydrogen buildup warrants a careful look at hydrogen venting capabilities for any plants that could suffer from the same design flaw.
• “The tsunami hazard for several sites was underestimated. … Defence in depth, physical separation, diversity and redundancy requirements should be applied for extreme external events, particularly those with common mode implications such as extreme floods.”Two terms in this point require some explanation. The first, “Defence in depth,” refers to having multiple, redundant, diverse and independent safety systems in place, especially in the case of a single incident that can affect many systems, known as a “common mode” incident. “Common mode” refers to thefact that one incident (such as the tsunami) can disable many safety systems at once. Nuclear power stations will have to be re-analyzed to ensure that, within reason, no single incident or chain of events can disable enough safety systems
  to cause a major malfunction.
• The IAEA mission urges the international nuclear community to take advantage of the unique opportunity created by the Fukushima accident to seek to learn and improve worldwide nuclear safety.The IAEA uses this opportunity to call for the world to learn from the Fukushima incident, in order to improve safety of all other nuclear plants. They see this as a learning opportunity, and there is indeed much information to be acquired by analyzing the situation as it develops.

  

  The picture belongs to Ben Hein

Nuclear Radiation

Radiation is the energy that travels in waves. It includes visible light, ultraviolet light, radio waves and other forms, including particles. Each type of radiation has different properties. Non-ionizing radiation can shake or move molecules. Ionizing radiation can actually break molecular bonds, causing unpredictable chemical reactions. Humans cannot see, feel, taste, smell or hear ionizing radiation. Unavoidable exposure to ionizing radiation comes from cosmic rays and some natural material. Human exposure to natural radiation is responsible for a certain number of mutations and cancers. Additional exposure above natural background radiation is cause for concern since it may result in otherwise preventable disease.

The levels of radiation risks and danger.

Where does ionizing radiation come from?

Ionizing radiation is matter or energy that is given off by the nucleus of an unstable atom in the process of decaying and reaching a stable (ground) state. This energy is released in the form of subatomic particles (alpha and beta) or waves (gamma and x rays). Most elements and their atoms are not radioactive. A few radioactive elements, like uranium, radium, and thorium, occur in nature. Humans, through nuclear power, bomb production and testing, have created and released manmade radioactive elements (radionuclides) that were previously unknown in the environment. Through mining and industrial processing naturally radioactive elements like uranium and thorium have been released to flow through the natural systems on which life depends. These substances were, with few exceptions, geologically isolated from the environment under layers of shale and quartz before human beings dug them up by the ton and contaminated the biosphere. Because of poorly conceived and implemented nuclear technologies, such as atomic energy, bomb production and reprocessing, we and our descendants are left with a legacy of radioactive waste with no proven isolation method.

…of Alpha, Beta and Gamma

Putting into retrospective, alpha particles are perceived as high energy, large subatomic structures. They can’t travel very far and can be stopped by a piece of paper or the human skin. However, alpha particles hit hard and are capable of doing a great deal of damage to the cells they rip through. Once inhaled, ingested or otherwise taken inside the body (as through a cut in the skin), they have the power to tear through cells in organs or blood, releasing their energy to surrounding tissue and leaving extensive damage in their wake. A single track of a single alpha particle can deliver a large dose of radiation to a cell. Plutonium is an alpha emitter. Other alpha emitters include radon gas, uranium, and americium.

Beta particles are electrons. They are just a fraction of the size of alpha particles and can travel farther and are more penetrating. Betas pose a risk both outside and inside the body, depending on their energy level. External exposure can result in beta penetration through the surface to the most sensitive layers of skin. Inhalation or ingestion of a beta emitting radionuclide poses the greatest risk. Externally, a half-inch of Plexiglas or water shielding can generally stop a beta. Strontium-90 and tritium are two beta-emitting radionuclide routinely released from nuclear power reactors during normal operation. Our bodies often mistake strontium-90 for calcium, collecting it in our bones that make our new blood cells. Once there, it increases our risk of bone and blood cancers like leukemia. Every one of us has strontium-90 in our bodies as a result of nuclear bomb testing. Tritium is radioactive hydrogen, which binds where normal hydrogen does. Hydrogen is the most abundant element on the earth, and is a component of water, which cushions our genetic material (DNA). Tritium can bond in this water, irradiating our DNA at very close range.

Gamma rays are the most penetrating type of radiation and can be stopped only by thick lead blocking their path. Cesium-137 is a gamma emitter often released from nuclear reactors. It mimics potassium, collecting in muscle. Iodine-131 and Iodine

Reference: http://www.oasisllc.com/abgx/radioactivity.htm

Nuclear power in Korea

In 1957 the Korean decides to join International Atomic Energy Agency not because they like the nuclear power but because they do not have enough fossil fuel resources. And for all of you out there routing against nuclear power here an example of what can the nuclear power delver and the other source of power cannot. So in 1962 Korea’s first research reactor achieved criticality. Since 1978 nineteen reactors were bulled that’s make total of  four with CANDU and the other sixteen with PWR technology. The first Korean reactor was kori-1 and it was built almost entirely by foreign contractors. Since then the KSNP (Korean Standardized Nuclear Plant) had developed and from 1995 until now they use 95% of their owned technology in building new nuclear reactors. Also in 2010 they went international by   impressing the United Arab Emirates and made their first export order of four APR1400 reactors. Also they were the first country to open a nuclear safety school.

Nuclear plants in South Korea

The total electrical generation capacity of the nuclear power plants of South Korea is 18.5 GWe from 21 reactors. This is 29.5% of South Korea’s total electrical generation capacity, but 45% of total electrical consumption. The South Korean nuclear power sector maintains capacity factors of over 95%. Despite the March 2011 Fukushima nuclear accident, South Korea remains a strong supporter of nuclear power. In October 2011, South Korea reconfirmed its position as a strong supporter of nuclear power with the hosting of a series of events to raise public awareness. The events were coordinated the Korea Nuclear Energy Promotion Agency (KONEPA) and included the participation of the French Atomic Forum (FAF); the International Atomic Energy Agency (IAEA); as well as public relations and information experts from countries that utilize or plan to utilize nuclear power.^[1]

Reference:

http://en.wikipedia.org/wiki/Nuclear_power_in_South_Korea

1. Korea, Junotane (October 22, 2011). “Korea reconfirms strong support for nuclear power”. Junotane. Retrieved 2011-10-22.

ITER

Fusion is the process at the core of our Sun. What we see as light and feel as warmth is the result of a fusion reaction: Hydrogen nuclei collide, fuse into heavier Helium atoms and release tremendous amounts of energy in the process.

In the stars of our universe, gravitational forces have created the necessary conditions for fusion. Over billions of years, gravity gathered the Hydrogen clouds of the early Universe into massive stellar bodies.  In the extreme density and temperature of their cores, fusion occurs.The main advantage of nuclear fusion over fission is that there virtually would not be any nuclear waste that is produced.

ITER (International Thermonuclear Experimental Reactor)  is a large-scale scientific experiment that aims to demonstrate that it is possible to produce commercial energy from fusion.

The Q in the formula on the right symbolizes the ratio of fusion power to input power. Q ≥ 10 represents the scientific goal of the ITER project: to deliver ten times the power it consumes. From 50 MW of input power, the ITER machine is designed to produce 500 MW of fusion power—the first of all fusion experiments to produce net energy.

During its operational lifetime, ITER will test key technologies necessary for the next step: the demonstration fusion power plant that will prove that it is possible to capture fusion energy for commercial use.

A cut-away view of the ITER Tokamak, revealing the donut-shaped plasma inside of the vacuum vessel.

If you want to find out more information about ITER, please refer to the link below.

Reference:

http://www.iter.org/

Nuclear power in Japan

The Japan nuclear power system started in 1954 with budgeted reaches 230 million yen.it was limited only to peaceful purposes. The first nuclear reactor in Japan was built by the UK’s GEC. In the 1970s the first Light Water Reactors were built in cooperation with American companies. These plants were bought from U.S. vendors such as General Electric or Westinghouse with contractual work done by Japanese companies, who would later get a license themselves to build similar plant designs. Developments in nuclear power since that time has seen contributions from Japanese companies and research institutes on the same level as the other big users of nuclear power. The program face a lot of resistances at the beginning as Robert Jay Lifton stat:

There was resistance, much of it from Hiroshima and Nagasaki survivors. But there was also a pattern of denial, cover-up and cozy bureaucratic collusion between industry and government, the last especially notorious in Japan but by no means limited to that country. Even then, pro-nuclear power forces could prevail only by managing to instill in the minds of Japanese people a dichotomy between the physics of nuclear power and that of nuclear weapons, an illusory distinction made not only in Japan but throughout the world.

 

 

 

 

 

 

 

Despite what happened in the world because of the Three Mile Island accident or the Chernobyl disaster. The Japan nuclear power program holds its ground through the 80s and the 90s and  construction of new plants continued to be strong.in the mid-90s there were several accidents occur in Japan , resulting in protests and resistance to new plants. These accidents included the Tokaimura nuclear accident, the Mihama steam explosion, cover-ups after an accidents at the Monju reactor, among others, more recently the Chūetsu offshore earthquake aftermath. While exact details may be in dispute, it is clear that the safety culture in Japan’s nuclear industry has come under greater scrutiny.Canceled plant orders include:

•  The Maki NPP at Maki, Niigata (Kambara)—Canceled in 2003
• The Kushima NPP at Kushima, Miyazaki—1997
• The Ashihama NPP at Ashihama, Mie—2000
• The Hōhoku NPP at Hōhoku, Yamaguchi—1994
• The Suzu NPP at Suzu, Ishikawa—2003

 

 

 

 

 

 

 

 

 

 

But the biggest hits that the program took was the Fukushima I Nuclear Power Plant disaster on  March 11, 2011, This was the first time a nuclear emergency had been declared in Japan, and 140,000 residents within 20 km of the plant were evacuated. The total amount of radioactive material released is unclear, as the crisis is ongoing. However an energy white paper, approved by the Japanese Cabinet in October 2011, says “public confidence in safety of nuclear power was greatly damaged” by the Fukushima disaster, and calls for a reduction in the nation’s reliance on nuclear power. It also omits a section on nuclear power expansion that was in last year’s policy review.

 

 

 

 

 

 

Reference:

http://en.wikipedia.org/wiki/Nuclear_power_in_Japan