Monthly Archives: February 2012

We’re expanding our Laboratory Equipment section with the addition of the Scilogex line of products. This new gear can be found among the Mini Centrifuges, Vortex Mixers, Hotplates/Stirrers, and Shakers. We also made a new category to accommodate their collection of Overhead Stirrers.

The Scilogex products complement our existing lineup by providing a premium option to accomplish a variety of common lab functions. The new items incorporate features like digital displays to make these everyday tasks a snap. For instance, the new Orbital Shakers have an RS232 interface so they can be controlled through a PC, and Scilogex models of Mini Centrifuges include bio-safe rotors and cooling systems.

Take a look at the brochures provided on the different category pages for detailed information on each the new models!

Yesterday news broke that the possible revolutionary findings of the physics experiments that detected particles traveling faster than the speed of light may have been corrupted by two mechanical errors, one of them being a loose cable. Since proof of particles breaking the speed of light would contradict Einstein’s special theory of relativity, not to mention certain principles of quantum mechanics, the initial report in September was met with a great deal of skepticism from the scientific community, and even members of the team that released the data expressed doubts at the time. Since the announcement, the research team and physicists around the world have been reviewing the results to see if they could detect any flaws in the experiment.

The tests were performed by the OPERA collaboration, a research venture between CERN and the Gran Sasso National Laboratory in Italy. Initially they measured neutrinos traveling from one location to another 450 miles away and found that some arrived 60 nanoseconds earlier than should be possible under the limits of light speed, creating a stir in scientific community.

Now the same team that made the finding has uncovered two flaws in the experimental design which may have altered the results. The first issue is that the GPS tracking system they used may have been providing incorrect timestamps. The second, more attention-grabbing, problem is a faulty connection between the cable linking the GPS signal to the master clock. Oddly enough, the two concerns would actually have opposite effects on the neutrino time measurements, so the question of how fast neutrinos actually move is hardly settled. More neutrino tests will be performed this spring using CERN’s Large Hadron Collider.

While some may look at the likely debunked results with a degree of snark, we can also look at this story as a reminder of how important it is to review your work. Because these particular results were so unusual and had such potential impact on modern science, close scrutiny was guaranteed. But what about our typical, everyday research? While the flaws in the OPERA team’s experiment are hardly cringe-worthy, I’m sure we can all recall incidents in our personal and professional lives in which a drastic oversight was made in a project. If anything, this should be an encouragement – even world-class physicists make the same mistakes we do. Though one advantage for physicists is that they can always just shrug and point to the Uncertainty Principle.

Read more about the OPERA experiments and the faulty cable discovery here.

Marine biology and Oceanography organizations have long used a variety of filter media to assist with their research. While the ways in which filtration supplies can be used are as diverse as the life forms that live under the waves, here we highlight a couple of these applications that have previously been mentioned in published papers to give you an idea about some ways filters can be purposed in marine research.

In a study on mercury content of the ocean area between Antarctica and Tasmania, researchers from the Ifremer Institute used the 0.2 Micron, 47 mm polycarbonate membrane filters to filter samples of seawater and brine prior to determining their mercury content through atomic fluorescence spectroscopy. The PCTE membranes were used in conjunction with Sartorius filtration devices and a Nalgene vacuum pump to attain filtered water in volumes between 100 and 1000 mL. By applying this filtration setup the researchers were able to find patterns in how mercury travels the ocean.

Another oceanographic use for filtration materials comes from the study of zooplankton that live deep in the Pacific Ocean. 1.2 Micron silver membrane filters were used to pre-filter samples of plankton waste prior to nitrogen content analysis via a high temperature combustion technique.

Also using silver membrane filters (1.2 Micron, 25 mm) was an experiment by the Woods Hole Oceanographic Institution which used them as part of a study to see if the growth of marine phytoplankton in certain areas leads to organic carbon being exported. Here the membranes were used to collect and prepare particles from deep water samples for further analysis.

Remember, these are just a few examples of how filters can be used in the marine sciences. If you’ve been doing your own tests with filter media, let us know in the comments!

An especially pungent use for glass fiber filters is described in the latest issue of the Soil Science Society of America Journal. In the paper, “Influence of Dissolved Carbon and Nitrogen on Mineralization of Dilute Liquid Dairy Manure” two scientists from the University of California examined the wastewater used to flush dairy cow waste for the presence of these elements.

On dairy farms in which the milk cows are confined, water is used to flush away the manure and is then stored in lagoons to be treated for coarse solids before being re-applied to crop fields through irrigation. Refuse reuse if you will. One problem with this procedure is that if there is too much dissolved Carbon or Nitrogen in the wastewater it can create groundwater contamination.

For this study, the researchers collected wastewater samples from seven lagoons and analyzed them in order to investigate the relationship between the starting levels of Nitrogen and Carbon and the wastewater’s mineralization behavior. Their methodology included determinations of Totals Solids (TS) and Total Suspended Solids (TSS) by filtering the manure through a series of glass fiber filters, including the Advantec GF75 (0.3 micron) at several points. The GF75 was also used to filter wastewater samples prior to gravimetric analysis.

In this case, the authors found that the amount of Nitrogen that will be mineralized for crop consumption is very likely due to how much dissolved Carbon and Nitrogen is present on denitrification. Further investigation will be needed before scientists can accurately predict how much Nitrogen the crops treated with this water are actually exposed to.

The full paper is available here for American Society of Agronomy subscribers.

In a case of good news/bad news for industrial workers, OSHA (the Occupational Safety and Health Administration) is getting a budget increase for 2012, but the money comes with a delay on a proposal that would further limit workers’ exposure to carcinogenic silica dust.

The backstory: Last February OSHA sent a proposal to the White House Office of Management and Budget that called for a reduction in the silica PEL¹ (Permissible Exposure Limit), which would be the first change to this regulation since the 1960’s². The plan was to get the approval of the OMB and then open up the proposal to public debate after 90 days, but one year later and OSHA is still waiting.

The reason for the snag is most likely because of concerns raised by the industries that would be financially affected by stricter controls. Some opponents of the new OSHA proposal argue that the government needs to do a better job of enforcing the current rules before making any changes to the exposure level. Congress seems to agree with this priority, as the largest line item increase in the new budget is $5 million for additional enforcement OSHA’s sister organization, MSHA (Mine Safety and Health Administration). Representatives for the impacted industries, such as construction and mining, also point out that they subject themselves to voluntary monitoring and medical treatment for certain silica levels and these measures have been effective at eliminating the health risks to workers.

Unfortunately for those who disagree with that assessment, a stricter regulation is unlikely to happen in the immediate future since with the upcoming elections lawmakers aren’t in a hurry to pass a regulation that could paint them as “anti-business.” So at least for now OSHA is going to have to use their bigger budget to make the current regulations work.

For more information on the new OSHA budget we recommend this piece by NPR and this writeup from Patton Boggs LLP.

1)  The PEL for silica is a little tricky to explain – there are several variables and conditions that prevent it from being expressed as a simple number. You can read this blog post from The Safety Director’s Cut for a detailed explanation.

2) While the acceptable levels may change, there aren’t any expected changes to the recommended procedure for evaluating crystalline silica – which involves filtering samples on silver membrane filters and X-Ray Diffraction analysis. You can find the full procedure from the CDC here.