« New approach for synthetic rubber for degradable tires: converting cyclopentene to polypentenamers | Main | AK Steel introduces NEXMET family of next generation high strength steels for automotive lightweighting » A study by researchers at Eindhoven University of Technology has found that the “persistent diesel dogma” of “the higher the cetane number (CN) the better” relative to the soot-NO trade-off is valid in neither conventional or low temperature combustion operation. The open-access study, published in the journal Fuel also reported that a second piece of conventional wisdom—“the lower the aromaticity the better”— is valid in both combustion modes. The researchers also devised a new, dimensionless parameter—Π—that holds distinct values for the various combustion modes. This can predict either a positive, neutral or negative impact of high CN and low aromaticity on the soot-NO trade-off based on a given set of engine operating conditions. When the investment decision was made to construct gas-to-liquid plants (GTL) plants, the conventional wisdom held at the time was the higher the cetane number (CN) the better. For most of the compression ignition’s (CI) history, this has proven to be correct. The underlying causality, however, is a bit more complex. As refineries invested heavily in cutting aromatic fractions, soot emissions dropped and engines ran smoother. These phenomena coincided with a rise in CN, a collateral result of removing the intrinsically low reactive aromatics from the cut. Given that this positive correlation between CN and overall engine performance was long accepted as a causality in the combustion community, it is not surprising that later GTL plants—as is frequently emphasized in associated marketing campaigns—were designed to produce as high CN as possible, limited only by a maximum paraffinic chain length owing to cold flow (e.g., wax forming) considerations. The Eindhoven team reviewed the extensive literature regarding the virtues of high CN, and tallied contradictory results, which they summarized, and from which they drew the following conclusions: For their study, the team conducted engine tests for a fuel matrix spanning a wide range of CN and aromaticity under both LTC, HTC and transitional regime operating conditions on a modified DAF heavy-duty CI engine (12.6-liter, in-line 6). Cylinder 1 was a dedicated test cylinder, the second and third cylinder had no function, and the remaining 3 cylinders were used to rotate the crankshaft to the desired RPM. The fuels were a standard diesel (CN 51.6), low-cetane Fischer-Tropsch GTL diesel (CN 52.1) and high-cetane FT (CN 71.8). Their new parameter Π effectively evaluated if aromaticity and CN impact the soot-NOx trade-off in a manner characteristic of either diffusion (HTC→Π>1) or premixed flames (LTC→Π
News Article | June 24, 2016
Aside from having a distant evolutionary ancestor, humans and monkeys have one thing in common: when both grow into old age, they become more selective with friends. You may have observed this behavior among your grandparents or your retiring parents. Some of them may opt to go alone on the same diner on the same days every week, some may get too cranky around strangers and some may prefer to watch TV by themselves. New research suggests that the same behavior occurs in monkeys, particularly in Barbary macaques. These animals tend to become less sociable as they age, just like humans. The question is: why? Scientists from the German Primate Center wanted to know how age affected the behavior of more than 100 Barbary macaques kept in an enclosure in a park in France. They investigated how the monkeys - whose ages ranged from 4 to 29 years (equivalent to 105 human years) - reacted to physical objects such as novel toys and tubes with food, social interactions such as fighting and grooming "friends" and new social information, such as calls and photos of "friends" and "strangers." Researchers discovered that the interest of Barbary macaques in toys wane when they become adults. At around 20 or the retirement age of monkeys, these animals approached fewer monkeys and had less social contact. What surprised scientists is that this obvious withdrawal was not prompted by a social affinity to avoid old monkeys. Younger ones still groomed and approached their elders. It also wasn't because older monkeys were not interested in anything at all. Scientists found that older monkeys still hissed to others during fights and still responded to photos of others. These older monkeys are still attuned to what is going on around them, but they do not want to participate, says Julia Fischer, one of the researchers of the study. The dominant psychological theory that could explain why this behavior happens in humans is that they want to maximize the time they have left with death on the horizon. Fischer says although monkeys have excellent memories, there is no evidence that they are self-aware about their impending deaths. So if both monkeys and humans act this way as they age, the theory may be rationalizing a natural behavior with biological roots, she says. Alexandra Freund, Fischer's co-researcher, says the findings of the study clearly tell us that we are not distinctive in how we grow into old age. "There might be an evolutionary 'deep' root in this pattern," says Freund. Fischer says whatever the reason for the similarity in behavior, the main takeaway from the research is that although how we act is much the result of our choice and deliberation, it might be more similar to our primate ancestors than we believe. Details of the study are published in the journal Current Biology. © 2016 Tech Times, All rights reserved. Do not reproduce without permission.
News Article | August 27, 2016
Great white sharks do not look maternal. With jaws like a vise, beady, obsidian eyes, and torpedo-shaped bodies, these predators seem far more menacing than motherly. But what if we found evidence to suggest otherwise? For the first time, biologists have located a great white “nursery,” where mother sharks deliver pups, alive and fully formed. Researchers with OCEARCH, an ocean research nonprofit, identified the site this week in waters off Montauk, Long Island. This monumental finding is “probably the most significant discovery we’ve ever made on the ocean,” said Chris Fischer, the founding chairman of OCEARCH. In an interview with CBS News, Fischer noted that great white birthing sites are regarded as “the holy grail of research,” and are especially important in the Atlantic Ocean, where the sharks are vulnerable to bycatch and sport fishing. It took OCEARCH 26 expeditions to find the nursery, which called on the efforts of both scientists and fishermen. Once they discovered its whereabouts, the crew tagged nine sharks in less than a week—a rarity, as some researchers can spend their entire careers without spotting even a single great white. Since then, multiple sharks have been captured and released by OCEARCH in a single day. Atlantic great whites tend to summer in the north, and spend their winters down south, but at any given time, they could be everywhere. When the team noticed that most of their catches were juveniles and pups, however, they knew that these weren’t just rogue wanderers. At some point, they realized mama was here. OCEARCH has helped to pioneer the field of great white tracking, and currently monitors several dozen individual sharks throughout global waters. By outfitting them with special dorsal fin tags, scientists are able to follow the sharks in real time, for up to a decade. The tagging process takes about 10 minutes, during which the shark’s gills are flushed with water. Using a power drill, a remote tracking sensor is fastened to their fin. If you’re concerned that this hurts the sharks, Fisher says not to worry—if it did, they wouldn’t be doing it. “The strategy at the time was to get a tag out on big mature animals, and when you get one on a big female, 18 months later, she should lead you to… the birthing site,” said Fischer. Researchers are eager to determine whether any of the young sharks captured in Montauk are the offspring of individuals tagged near Cape Cod. According to Haley Newton, a veterinary pathologist with the Wildlife Conservation Society who has been working on the expedition, juvenile great whites are vastly understudied, simply because they’re so difficult to find. Earlier this year, scientists with the Long Island Shark Collaboration managed to tag the first ever great white pup in the Atlantic Ocean. Despite being the most infamous predator in the sea, great whites are disproportionately mysterious. No one has witnessed a female giving birth, and biologists aren’t sure what their mating behavior entails. Great whites are known to migrate in tangents, but what compels them to wander for thousands of miles remains speculative. Every winter, great whites inexplicably gather near a spot called the “white shark café,” somewhere between Mexico and Hawaii in the Pacific Ocean. Scientists have no idea what’s so special about this location, but they know that here male sharks will dive up to 200 meters deep, as many as 150 times per day—behavior that’s considered abnormal for great whites. In 2017, a crew from the Monterey Bay Aquarium plans to record the sharks’ activity using custom-made “swimming robots.” The data collected by OCEARCH will hopefully reveal new insights about great white life stages, especially those of young pups. In addition to tracking their locations, scientists will be analyzing blood and parasite samples collected from the sharks. Ultimately, their findings will help to inform conservation decisions in the Atlantic Ocean, where great white populations are estimated to have declined by 75 percent in the last 15 years. Worldwide, the total number of sharks killed by humans every year has skyrocketed to 100 million, due to threats such as finning, bycatch, sport fishing, and habitat destruction. Thankfully, organizations like OCEARCH are not only directly contributing to shark science, but are also making the public aware of the animal’s conservation status. Their most notable research subject is a 16-foot female, affectionately named “Mary Lee,” after Fischer’s own mother. Weighing in at 3,400 pounds, she was last seen off the coast of South Carolina, and has traveled more than 34,000 miles since being tagged. She even has her own Twitter account, which may not help to dispel the myth about sharks loving the internet. If you’re feeling curious, all of the sharks tagged off Long Island are now pinging their locations to OCEARCH’s live-tracker. Where, exactly, will “Hampton,” “Montauk,” and the others go? That’s for you to find out.
"The Senate has approved a bill overhauling federal energy pipeline rules and reauthorizing the main agency overseeing pipeline safety in a vote Thursday. The legislation, from a bipartisan group of lawmakers led by Sens. Deb Fischer (R-Neb.) and Cory Booker (D-N.J.) reauthorizes the Pipeline and Hazardous Materials Safety Administration (PHMSA) through 2019 and takes new steps to cut down on spills and other problems with the American pipeline network. The Senate approved the bill on a unanimous cosent Thursday evening."
« China researchers discover that Li-ion battery cycling can control magnetization | Main | Tesla delivered 50,580 EVs in 2015; 17,400 in Q4 2015 » Fulcrum BioEnergy, the parent company of Fulcrum Sierra BioFuels, has applied for a new fuel pathway under the California Low Carbon Fuel Standard (LCSF) for its process of converting municipal solid waste (MSW) into Fischer-Tropsch (“FT”) diesel fuel. The California LCFS mandates a 10% reduction by 2020 in the carbon intensity (CI) of transportation fuels. The program requires that transportation fuels used in California meet a baseline target for carbon intensity which is reduced each year. For 2016, the target for diesel and diesel substitutes is 99.97 gCO e/MJ (Earlier post.) Fulcrum is requesting a CI of 37.47 g/MJ for its MSW-to-FT diesel. Sierra BioFuels’ MSW-to-FT diesel fuel facility, which is currently under construction in Nevada, consists of a Feedstock Processing Facility and a biorefinery. The Feedstock Processing Facility will receive MSW that otherwise would have been landfilled. A feedstock processing system shreds, screens, and sorts the MSW producing a MSW-derived feedstock meeting the feedstock specification required for conversion into renewable fuel at the biorefinery. Recyclable materials are recovered and sold to the commodity market. Residual materials (e.g. inerts, high moisture content waste) are sent to the landfill. The MSW feedstock is transported to the biorefinery where it is converted to FT diesel using a three-step process comprising steam reforming gasification; FT liquids synthesis; and hydroprocessing upgrading. Natural gas is used for process energy and additional power is imported from the grid. The avoided landfill emissions follow the California ARB approach used for waste material pathways. ARB staff recommended approval of the prospective pathway with the requested CI value. Fuels with prospective CIs are not eligible to claim credits under the LCFS. ARB will require the applicant to provide one quarter of operational data once commercial production has commenced. Staff will then complete an updated lifecycle analysis and if warranted, make necessary adjustments to the originally certified prospective CI and approve a provisional CI for the pathway. Sierra designed its biorefinery to produce more than 10 million gallons per year of renewable FT syncrude from approximately 200,000 tons of prepared MSW feedstock that would otherwise be landfilled. This renewable FT syncrude will be upgraded and processed into a low-carbon diesel or jet fuel product.