Mold susceptibility of rapidly renewable materials used in wall construction

Since 1998, the United States Green Building Council, via the Leadership in Energy and Environmental Design (LEED) standards, has established the premiere set of guidelines for construction ethics from the standpoint of eco-friendliness and occupant safety and health in the U.S. and around the world. These guidelines are skyrocketing in use due in part to two reasons: · increased awareness of a need for reducing, reusing, and recycling in order to save resources and natural areas for future generations; and, · increased amount of time spent indoors in work places and homes. The LEED guidelines encourage sustainable and responsible use of land, water, energy, and materials, and promote a safe and healthy environment through use of innovative designs and technology. As part of the responsible use of materials, the LEED guidelines encourage the use of rapidly renewable materials such as cotton, straw, wool, and cork as insulation products. Although these products can be produced naturally and quickly from nature, they are also cellulose or carbohydrate based products. Cellulose and carbohydrate based materials are typically optimal food sources for mold in the presence of moisture, ironically destroying facilities and creating poor living and work environments. Samples of wool, cork, straw, and cotton--rapidly renewable materials used as exterior wall insulation products--were exposed to different moisture amounts in an encapsulated environment, representing the environment within a wall cavity when exposed to water from pipes, leaks, condensation and absorption, or from initial construction. The samples were monitored over time for mold growth. The data logged from the samples were analyzed to determine the degree of mold susceptibility of each material. In addition, samples with increased amounts of moisture were examined to determine increased promotion of mold growth. The results from this study showed that all of the above mentioned materials were highly susceptible to mold growth and that the moisture amount did not increase the rate of mold growth. Based on the data collected from this study, recommendations were made to review the current use of rapidly renewable and other cellulose and carbohydrate based materials in wall construction

Mold susceptibility of rapidly renewable materials used in wall construction

Since 1998, the United States Green Building Council, via the Leadership in Energy and Environmental Design (LEED) standards, has established the premiere set of guidelines for construction ethics from the standpoint of eco-friendliness and occupant safety and health in the U.S. and around the world. These guidelines are skyrocketing in use due in part to two reasons: · increased awareness of a need for reducing, reusing, and recycling in order to save resources and natural areas for future generations; and, · increased amount of time spent indoors in work places and homes. The LEED guidelines encourage sustainable and responsible use of land, water, energy, and materials, and promote a safe and healthy environment through use of innovative designs and technology. As part of the responsible use of materials, the LEED guidelines encourage the use of rapidly renewable materials such as cotton, straw, wool, and cork as insulation products. Although these products can be produced naturally and quickly from nature, they are also cellulose or carbohydrate based products. Cellulose and carbohydrate based materials are typically optimal food sources for mold in the presence of moisture, ironically destroying facilities and creating poor living and work environments. Samples of wool, cork, straw, and cotton--rapidly renewable materials used as exterior wall insulation products--were exposed to different moisture amounts in an encapsulated environment, representing the environment within a wall cavity when exposed to water from pipes, leaks, condensation and absorption, or from initial construction. The samples were monitored over time for mold growth. The data logged from the samples were analyzed to determine the degree of mold susceptibility of each material. In addition, samples with increased amounts of moisture were examined to determine increased promotion of mold growth. The results from this study showed that all of the above mentioned materials were highly susceptible to mold growth and that the moisture amount did not increase the rate of mold growth. Based on the data collected from this study, recommendations were made to review the current use of rapidly renewable and other cellulose and carbohydrate based materials in wall construction

The Lick AGN Monitoring Project 2011: Dynamical Modeling of the Broad Line Region in Mrk 50

We present dynamical modeling of the broad line region (BLR) in the Seyfert 1 galaxy Mrk 50 using reverberation mapping data taken as part of the Lick AGN Monitoring Project (LAMP) 2011. We model the reverberation mapping data directly, constraining the geometry and kinematics of the BLR, as well as deriving a black hole mass estimate that does not depend on a normalizing factor or virial coefficient. We find that the geometry of the BLR in Mrk 50 is a nearly face-on thick disk, with a mean radius of 9.6(+1.2,-0.9) light days, a width of the BLR of 6.9(+1.2,-1.1) light days, and a disk opening angle of 25\pm10 degrees above the plane. We also constrain the inclination angle to be 9(+7,-5) degrees, close to face-on. Finally, the black hole mass of Mrk 50 is inferred to be log10(M(BH)/Msun) = 7.57(+0.44,-0.27). By comparison to the virial black hole mass estimate from traditional reverberation mapping analysis, we find the normalizing constant (virial coefficient) to be log10(f) = 0.78(+0.44,-0.27), consistent with the commonly adopted mean value of 0.74 based on aligning the M(BH)-{\sigma}* relation for AGN and quiescent galaxies. While our dynamical model includes the possibility of a net inflow or outflow in the BLR, we cannot distinguish between these two scenarios.Comment: Accepted for publication in ApJ. 8 pages, 6 figure

Coronal Heating as Determined by the Solar Flare Frequency Distribution Obtained by Aggregating Case Studies

Flare frequency distributions represent a key approach to addressing one of the largest problems in solar and stellar physics: determining the mechanism that counter-intuitively heats coronae to temperatures that are orders of magnitude hotter than the corresponding photospheres. It is widely accepted that the magnetic field is responsible for the heating, but there are two competing mechanisms that could explain it: nanoflares or Alfv\'en waves. To date, neither can be directly observed. Nanoflares are, by definition, extremely small, but their aggregate energy release could represent a substantial heating mechanism, presuming they are sufficiently abundant. One way to test this presumption is via the flare frequency distribution, which describes how often flares of various energies occur. If the slope of the power law fitting the flare frequency distribution is above a critical threshold, $\alpha=2$ as established in prior literature, then there should be a sufficient abundance of nanoflares to explain coronal heating. We performed $>$600 case studies of solar flares, made possible by an unprecedented number of data analysts via three semesters of an undergraduate physics laboratory course. This allowed us to include two crucial, but nontrivial, analysis methods: pre-flare baseline subtraction and computation of the flare energy, which requires determining flare start and stop times. We aggregated the results of these analyses into a statistical study to determine that $\alpha = 1.63 \pm 0.03$. This is below the critical threshold, suggesting that Alfv\'en waves are an important driver of coronal heating.Comment: 1,002 authors, 14 pages, 4 figures, 3 tables, published by The Astrophysical Journal on 2023-05-09, volume 948, page 7

Precision measurement of the structure of the CMS inner tracking system using nuclear interactions

The structure of the CMS inner tracking system has been studied using nuclear interactions of hadrons striking its material. Data from proton-proton collisions at a center-of-mass energy of 13 TeV recorded in 2015 at the LHC are used to reconstruct millions of secondary vertices from these nuclear interactions. Precise positions of the beam pipe and the inner tracking system elements, such as the pixel detector support tube, and barrel pixel detector inner shield and support rails, are determined using these vertices. These measurements are important for detector simulations, detector upgrades, and to identify any changes in the positions of inactive elements

Precision measurement of the structure of the CMS inner tracking system using nuclear interactions

The structure of the CMS inner tracking system has been studied using nuclear interactions of hadrons striking its material. Data from proton-proton collisions at a center-of-mass energy of 13 TeV recorded in 2015 at the LHC are used to reconstruct millions of secondary vertices from these nuclear interactions. Precise positions of the beam pipe and the inner tracking system elements, such as the pixel detector support tube, and barrel pixel detector inner shield and support rails, are determined using these vertices. These measurements are important for detector simulations, detector upgrades, and to identify any changes in the positions of inactive elements