The Home of JEROME
High Quality Mercury and Hydrogen Sulfide Analyzers
Friday, July 26, 2013
Tuesday, July 16, 2013
Hydrogen Sulfide in Beer and Wine
HYDROGEN SULFIDE IN
BEER AND WINE
Summer is here. And
what activity better exemplifies summer than sitting by the pool, taking in the
sun’s bounty, and enjoying an ice cold beer? However, if that beer smells
faintly of rotten eggs or has a dreaded “skunky” flavor it can ruin an
otherwise idyllic afternoon.
So what causes these undesirable off flavors? During
fermentation the yeast which converts simple sugars into alcohol also naturally
produce some hydrogen sulfide (H2S). Low levels of H2S
are actually desirable and give the beer complex, defining flavor
characteristics. However at higher concentrations H2S is responsible
for the off-putting rotten egg smell, and the interaction of H2S
with the hops used in the brewing process are responsible for the skunky odor
in bad beer. Excess H2S can
be a symptom of unhealthy yeast, microbial infection, improper oxygen levels
during fermentation, or a myriad of other root causes.
Due to the volatility of H2S (b.p. = -60°C), one
effective method for testing the concentration of dissolved H2S is
to test the headspace above the liquid. If the temperature and accumulation
time are well controlled, then the concentration of H2S in the
headspace will be proportional to the concentration of H2S dissolved
in the sample. Brewers have sophisticated sensors in their fermentation tanks
to monitor the H2S concentration during production, but as anyone
who has bought an off case of beer knows, bad beer can sometimes make it into
the bottle.
Figure 1: Apparatus
Setup for determination of H2S in beer by Jerome®J605
Arizona Instrument LLC has a solution for the determination
of H2S in bottled beer using the Jerome® J605 Hydrogen Sulfide Analyzer.
The method can be run in under seven minutes and can be used to determine H2S
concentration in beer as low as 5 parts per billion (ppb). No hazardous
materials are required for testing. The instrument response over the range
investigated was linear with respect to concentration.
To run a test, an
Erlenmeyer vacuum flask is connected to a Jerome® J605 Hydrogen Sulfide
Analyzer by tygon or other suitably sized inert tubing. A full bottle of beer
is poured into an Erlenmeyer flask and allowed to stir for 5 minutes. The
instrument is placed in auto range and auto sample, sampling the head-space
above the beer every 2 minutes. The
instrument is allowed to sample for 30 minutes, and the results are then
summed.
James A. Moore, Garrett
M. Rowe
Research Group, Arizona Instrument LLC
For more information contact us at (800)528-7411 | sales@azic.com | www.azic.com
For a full copy of the method and accompanying data contact Arizona Instrument LLC.
For a printable version visit www.azic.com
Wednesday, April 17, 2013
How does Atomic Fluorescence Spectroscopy measure up?
Jerome® J505 Portable Atomic Fluorescence Spectroscopy
Mercury Vapor Analyzer
Introduction
Whether it is fluorescent lighting, dental fillings, antique switches, gold mining or thermometers, the element mercury (Hg) is present in the world we live. Many of the mercury containing products give us comfort, are used to provide us with information, and even allow us to control our environment. While these products are safe, they could potentially expose people to a plethora of toxic compounds if an accident should occur. Symptoms of mercury exposure include seizures, memory loss, and in some cases, death. Because of these risks, several guidelines and regulations have been developed that limit the amount of mercury people can be exposed to, and special methods are required for cleaning up mercury if an accident should occur. Currently the time weighted average limit for mercury varies depending on regulating agency. For OSHA, the limit is 0.1mg/m3*; NIOSH sets the limit at 0.05mg/m3*; and the ACGIH has a limit of 0.025mg/m3*. Since mercury vapor is not something people can see, how do they determine their amount of exposure? Arizona Instrument, LLC manufactures the J505 Atomic Fluorescence Analyzer; a handheld atomic fluorescence spectrophotometer that measures the concentration of mercury in air. The lower detection limit of this instrument is 50ng/m3 (0.000050mg/m3), and it can detect as high as 0.5mg/m3. These detection limits exceed the current industrial exposure limits, as well as clean-up levels for public facilities.
Atomic Fluorescence Spectroscopy (AFS)
Whether it is fluorescent lighting, dental fillings, antique switches, gold mining or thermometers, the element mercury (Hg) is present in the world we live. Many of the mercury containing products give us comfort, are used to provide us with information, and even allow us to control our environment. While these products are safe, they could potentially expose people to a plethora of toxic compounds if an accident should occur. Symptoms of mercury exposure include seizures, memory loss, and in some cases, death. Because of these risks, several guidelines and regulations have been developed that limit the amount of mercury people can be exposed to, and special methods are required for cleaning up mercury if an accident should occur. Currently the time weighted average limit for mercury varies depending on regulating agency. For OSHA, the limit is 0.1mg/m3*; NIOSH sets the limit at 0.05mg/m3*; and the ACGIH has a limit of 0.025mg/m3*. Since mercury vapor is not something people can see, how do they determine their amount of exposure? Arizona Instrument, LLC manufactures the J505 Atomic Fluorescence Analyzer; a handheld atomic fluorescence spectrophotometer that measures the concentration of mercury in air. The lower detection limit of this instrument is 50ng/m3 (0.000050mg/m3), and it can detect as high as 0.5mg/m3. These detection limits exceed the current industrial exposure limits, as well as clean-up levels for public facilities.
Atomic Fluorescence Spectroscopy (AFS)
When an atom is
excited by an input of energy, one of its electrons transitions from a stable
ground state to an unstable excited state.
Once the source of energy is removed, the electron returns to its ground
state and the absorbed energy is emitted as a photon (light). This process is called fluorescence. Often the amount of energy given off is not
the same as the energy going in. This is
not the case for mercury, which makes it special. When the energy required to excite an
electron is the same energy as the photon it gives off when it returns to its
ground state, it is called resonance fluorescence, and is easily detectable
using AFS. The J505 instrument uses a mercury
lamp to excite the mercury atoms at the 254nm wavelength, and then uses a
detector to measure the emission of the photons, at the same wavelength, as the
electrons return to their stable ground states. Because AFS measures the
emission of photons, this technique does not have interferences, such as hydrocarbons,
hydrogen sulfide, and ammonia, which are often problematic for traditional
detection methods. The specifications
for the J505 Atomic Fluorescence Analyzer are below.
Atomic Fluorescence Spectroscopy should not be confused with Atomic Absorption Spectroscopy (AAS). In AAS, a light source of known wavelength and intensity is passed through a sample of interest. Some of the energy of the source light is absorbed by the sample as it energizes electrons in the material from the ground state to an excited state. A detector is placed at the end of the pathway to determine how much of the energy passed through. The difference between the energy of the source light and the energy of the light that arrives at the detector is directly proportional to the concentration of analyte in the sample. One of the drawbacks of this technique is that there are a number of other common molecules that can absorb energy at the same wavelength as mercury. To compensate for these unwanted absorptions, manufacturers use a variety of filtering techniques to limit background interference. While these filtration principles are sound, they come at the cost of a more complicated and bulkier instrument. Further, AAS can also have physical limitations that may limit low level sensitivity. At very low concentrations, the amount of absorbed light, when compared to the intensity of the incident light source, can become indistinguishable from electronic noise, making detection at these levels more challenging.
Atomic Fluorescence Spectroscopy should not be confused with Atomic Absorption Spectroscopy (AAS). In AAS, a light source of known wavelength and intensity is passed through a sample of interest. Some of the energy of the source light is absorbed by the sample as it energizes electrons in the material from the ground state to an excited state. A detector is placed at the end of the pathway to determine how much of the energy passed through. The difference between the energy of the source light and the energy of the light that arrives at the detector is directly proportional to the concentration of analyte in the sample. One of the drawbacks of this technique is that there are a number of other common molecules that can absorb energy at the same wavelength as mercury. To compensate for these unwanted absorptions, manufacturers use a variety of filtering techniques to limit background interference. While these filtration principles are sound, they come at the cost of a more complicated and bulkier instrument. Further, AAS can also have physical limitations that may limit low level sensitivity. At very low concentrations, the amount of absorbed light, when compared to the intensity of the incident light source, can become indistinguishable from electronic noise, making detection at these levels more challenging.
* These TWA
averages are dependent on time. For more
information on exposure limits please
visit each respective website.
J505 Specifications
Test
Mode
Units:
|
ng/m3
|
µg/m3
|
mg/m3
|
Standard
Range
|
50 to 500,000
|
.05 to 500
|
0.00005 to
0.50000
|
(0.05 µg/m3 ± 0.033
µg/m3 to 500 µg/m3 ± 40 µg/m3)
|
|||
Resolution
|
10
|
0.01
|
0.00001
|
Quick
Range
Resolution
|
100 to 500,000
100
|
0.1 to 500
0.1
|
0.0001 to 0.500
0.0001
|
Search
Range
Resolution
|
100 to 500,000
100
|
0.1 to 500
0.1
|
0.0001 to 0.500
0.0001
|
Typical Test
Time
Standard
Quick
Search
|
28
seconds
16
seconds
8
seconds for first reading then continuous 1 second updates
|
||
Power
requirements
|
Internal battery (NiMH) with
10+ hours of operation
12VDC power adapter runs on
100-240VAC, 0.8A, 50-60Hz
Battery charges in 3 hours or
less
(Note: Battery will not charge
if battery temperature > 40 °C)
|
||
Operating
environment
|
5 to 45 °C, non-condensing,
non-explosive
|
||
Dimensions
|
12in L x 6.2in W x 8.4in H
(30.5cm L x 15.7cm W x 21.3cm
H)
|
||
Weight
|
6.5 pounds (3.0 kilograms)
|
||
Display
|
3.5 inch (9 cm) color LCD
display.
High brightness backlight
|
||
Unattended
Autosample
|
Available in intervals of 1, 2,
5, 10, 15, 20, 30, 45, 60, 90 or 120 minutes
|
||
Data
storage capacity
|
Up to 10,000 test results
100 test sites
|
||
USB
|
USB port located on rear of
instrument
Test results and calculations
saved to USB flash drive
Menu navigation, text entry,
and softkey operation with optional USB Keyboard
|
||
Certifications
|
Power adapter marked with UL
and TUV
|
Accuracy and
Precision (Standard mode):
Gas Level
|
Accuracy
|
Precision (RSD)
|
0.3 µg/m3
|
±
15%
|
15%
|
1 µg/m3
|
±
10%
|
7%
|
25 µg/m3
|
±
10%
|
5%
|
100 µg/m3
|
±
10%
|
3%
|
James Moore, Chemist
Arizona Instrument LLC
sales@azic.com | www.azic.com
Arizona Instrument LLC
sales@azic.com | www.azic.com
Friday, April 6, 2012
NEW! Portable Atomic Fluorescence Spectroscopy Mercury Vapor Analyzer
|
Tuesday, January 10, 2012
Mercury Poisoning
Mercury Poisoning
In December 2011, EPA issued the first national standards for mercury pollution from power plants. MATS are the first national standards to protect American families from power plant emissions of mercury and toxic air pollution like arsenic, acid gas, nickel, selenium, and cyanide. The standards will slash emissions of these dangerous pollutants by relying on widely available, proven pollution controls that are already in use at more than half of the nation's coal-fired power plants. Read the press release | Learn more about these actions | Read the final rule (PDF).
Mercury poisoning (also known as hydrargyria or mercurialism) is a disease caused by exposure to mercury or its compounds. Mercury (chemical symbol Hg) is a heavy metal occurring in several forms, all of which can produce toxic effects in high enough doses. Its zero oxidation state Hg0 exists as vapor or as liquid metal, its mercurous state Hg+ exists as inorganic salts, and its mercuric state Hg2+ may form either inorganic salts or organ mercury compounds; the three groups vary in effects. Toxic effects include damage to the brain, kidney, and lungs. Mercury poisoning can result in several diseases, including acrodynia (pink disease), Hunter-Russell syndrome, and Minamata disease.
In December 2011, EPA issued the first national standards for mercury pollution from power plants. MATS are the first national standards to protect American families from power plant emissions of mercury and toxic air pollution like arsenic, acid gas, nickel, selenium, and cyanide. The standards will slash emissions of these dangerous pollutants by relying on widely available, proven pollution controls that are already in use at more than half of the nation's coal-fired power plants. Read the press release | Learn more about these actions | Read the final rule (PDF).
Mercury poisoning (also known as hydrargyria or mercurialism) is a disease caused by exposure to mercury or its compounds. Mercury (chemical symbol Hg) is a heavy metal occurring in several forms, all of which can produce toxic effects in high enough doses. Its zero oxidation state Hg0 exists as vapor or as liquid metal, its mercurous state Hg+ exists as inorganic salts, and its mercuric state Hg2+ may form either inorganic salts or organ mercury compounds; the three groups vary in effects. Toxic effects include damage to the brain, kidney, and lungs. Mercury poisoning can result in several diseases, including acrodynia (pink disease), Hunter-Russell syndrome, and Minamata disease.
Symptoms of mercury poisoning typically include sensory impairment (vision, hearing, speech), disturbed sensation and a lack of coordination. The type and degree of symptoms exhibited depend upon the individual toxin, the dose, and the method and duration of exposure.
Mercury Toxicity Limits
Mercury Toxicity Limits
Country | Regulating agency | Regulated activity | Medium | Type of mercury compound | Type of limit | Limit |
US | Occupational Safety and Health Administration | occupational exposure | air | elemental mercury | Ceiling (not to exceed) | 0.1 mg/m³ |
US | Occupational Safety and Health Administration | occupational exposure | air | organic mercury | Ceiling (not to exceed) | 0.05 mg/m³ |
US | Food and Drug Administration | drinking | water | inorganic mercury | Maximum allowable concentration | 2 ppb (0.002 mg/L) |
US | Food and Drug Administration | eating | seafood | methylmercury | Maximum allowable concentration | 1 ppm (1 mg/L) |
US | Environmental Protection Agency | drinking | water | inorganic mercury | Maximum contaminant level | 2 ppb (0.002 mg/L) |
Monday, January 9, 2012
New Employee Annoucement
Arizona Instrument LLC welcomes Idonia Mancillas to the Marketing Department! Idonia has joined us from the Customer Service Department. She has been doing a phenomenal job for our company in the service department for nearly 5 years, and will be a huge asset to the Marketing Department.
Her official title will be Marketing Specialist, and she will be handling our tradeshow shipping coordination, sales literature requests and lead entry. We are so excited to have her on the Marketing Team!
Shari Moore
Marketing Manager
Arizona Instrument LLC
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