Measuring blast induced rock damage from pre-splitting sandstone by applying the multichannel analysis of surface waves geophysical method

Many blasting applications in the mining industry demand that the hard rock being blasted remains structurally competent. For example, pre-splitting is a common technique to reduce fracturing, and operators of dimension stone quarries use this blasting method to eliminate overbreak. When pre-split design parameters are not applied correctly, there will be a redistribution of stresses within the rock, resulting in Blast Induced Rock Damage (BID). Advances in geophysical technology are enabling blast technicians to monitor BID and then use the results to correctly design their blasts. The Multichannel Analysis of Surface Waves (MASW) geophysical method is new technology that is applied in many industries to determine the structural integrity of the subsurface. However, it has never been applied to monitor and quantify BID. Nonetheless, the author of this research intended to determine whether the MASW geophysical method can be applied on a large scale in surface mining by quantifying the amount of BID that is produced from pre-splitting and comparing this BID to rock mass competency, and high-wall stability. The author did so by performing a series of pre-split shots at a sandstone dimension stone quarry. Pre and post blast MASW surveys were gathered and compared to determine the extent that unwanted damage was occurring from the pre-split at specific depth intervals from the split line. The MASW method will produce high resolution data when it is used in optimal conditions. However, geological anomalies that are typical at mine sites prevent accurate MASW data to be processed with high resolution. Therefore, MASW is not applicable to monitor BID produced from pre-splitting with precision. However, MASW is capable of collecting detailed information at mine sites when it is performed on a large scale and this research shows that it will identify zones where the stone has been disturbed from the blast at depths several meters from the split line which compromises the structural integrity of the remaining rock mass and negatively influences the outcome of later shots performed in that area. This research generated recommendations for work that could be done to further utilize the MASW method as it was intended for --Abstract, page iii

Molyneux's Problem in the Scottish Enlightenment

Peer reviewedPostprin

Effects of different agricultural management systems on arbuscular mycorrhizal fungal diversity, community structure, and ecosystem services.

Disturbances associated with row-crop agricultural management systems include mechanical (tillage and cultivation) and chemical (fertilizer, pesticides, herbicides, fungicides) inputs and are often co-occurring. Many soil microbes are sensitive to these disturbances, including arbuscular mycorrhizal fungi (AMF), important plant mutualists in agricultural systems. AMF associate with many crop plants and provide direct benefits through root pathogen protection, drought resistance, nutrient acquisition and uptake, as well as contribute to ecosystem services by improving overall soil fertility. Examining how different row-crop management system disturbances affect the AMF community is important for understanding and enhancing benefits provided by these important mutualists, and key to developing sustainable agro-ecosystems. For this work I surveyed AMF community composition, structure, and AMF related functions in no-till, biologically-based/organic, early succession, and conventional management plots at the Kellogg Biological Station-Long Term Ecological Study Main Cropping System Experiment. I examined the effects of tillage and chemical inputs on AMF through an intensive sampling from 2010 to 2012. I also examined the historical effects of these different row crop agricultural management systems on AMF community and function by surveying archived soil samples taken annually following establishment of this site in 1989. Finally, I examined effects of the different management systems on the functioning of whole soil microbial communities in a controlled greenhouse experiment. Overall, I found that AMF communities respond differently to tillage and chemical input disturbances associated with management. Although long term trends indicate a reduction in both AMF richness and diversity for all row crop management systems, short term richness and diversity were higher in conventional, organic, and reduced input plots, as compared to the no-till and early succession systems. I found AMF community structure to be differently affected by tillage and chemical inputs. For example, AMF community composition and structure was most similar between the conventional and no-till row crop systems, and the reduced input and organic systems, when controlling for year/crop effects, indicating an effect of chemical input on the AMF community. I found measures of AMF function, specifically plant root colonization, to be robust to management system inputs. Under row-crop management, ecosystem services linked to soil carbon sequestration and water-stable aggregate formation and provided by AMF derived soil glomalin, were lower in conventional compared to the organic systems. All active agricultural systems had lower levels of soil glomalin as compared to old fields (agricultural abandonment). My results suggest AMF community composition, structure, and function are altered by these different row crop agricultural management systems, and ecosystem services currently provided by AMF are limited by both historical (+100 years) and continued management input disturbances. Following total abandonment of agricultural management, there is some restoration of AMF community structure and function and increased AMF contribution to ecosystem services, but these improvements in function are likely not similar to the functioning of the original soil microbial community

Apple Varieties in Maine

The following pages represent an effort to trace the causes of the changing procession of varieties of apples grown in Maine. To this end the history of fruit growing in Maine has been carefully studied, largely through the Agricultural Reports from 1850 to 1909 and the columns of the Maine Farmer from 1838 to 1875. The inquiry has been confined as rigidly as possible to this state, outside sources being referred to only for sake of comparison. Rather incidentally, soil influences, modifications due to climate, etc., have been considered. Naturally, since the inquiry was limited to printed record, nothing new has been discovered in this study. Perhaps a somewhat new point of view has been achieved. And, since early Maine pomological literature has been rather neglected by our leading writers, some few forgotten facts have been exhumed. A small amount of information has been collected in regard to Honey Pink; a little has been added to the commonly known history of the High- top Sweet; notices of Winthrop Greening and of Hunt Russet prior to any recorded in standard literature have been found and authenticated histories of Hubbardston and of Tolman Sweet have been carried back a little further

Winter injury of fruit in Missouri

Caption title.Digitized 2006 AES MoU

Mapping the Epoch of Reionization with C+ Line Tomography

Our KISS program has laid the theoretical foundations for probing the epoch of reionization with C+ tomography measurements, developed unique lithographed millimeter-wave spectrometer technology, and initiated a first-light C+ experiment named TIME-Pilot. With KISS support we have carried out the following investigations: 1) Developed the case for line intensity mapping methods to study the epoch of reionization using singly ionized carbon (C+), typically the most luminous emission line in galaxies. The theoretical studies not only explored the amplitude of the signal, and the usefulness in determining physical properties of the partially ionized intergalactic medium, but also the effects of foreground confusion from low-redshift galaxies. Our team made the first calculations of C+ clustering fluctuations from the reionization epoch, and estimated the effect of foreground galaxy confusion, largely from CO line emission at z ~ 1. We also authored the first papers on tomographic measurements with the Ly emission line, which shows great promise for near-infrared intensity mapping measurements with the SPHEREx SMEX mission concept. 2) Developed a complete design for a first-detection instrument of [CII] large-scale clustering emission named TIME-Pilot, based on an array of 32 novel waveguide spectrometers. The spectrometers are mounted in a linear array in two polarizations, and observations are carried out by scanning the detectors in a 1-deg linear strip, which maximizes depth (small survey area) while preserving sensitivity on large scales (long scan length). 3) Demonstrated the key waveguide spectrometer technology, which confines radiation in 2 dimensions and the power propagates between parallel plates and is dispersed and collimated by a curved grating. The waveguide spectrometers greatly reduce the mass and volume that would otherwise be required with a conventional 3-d grating spectrometer. 4) Demonstrated a prototype superconducting detector array. These high-sensitivity superconducting bolometers are mounted on the focal surface across multiple spectrometers, and read out by superconducting current amplifiers. The devices present unique micro-machining challenges to produce edge-butted sub-arrays that do not leave spectral gaps between channels. 5) Completed the full cryogenic system for the instrument. We commandeered an existing 4 K cryostat from another project, and added cooling stages to an ultimate temperature of 220 mK to meet the TIME-Pilot cooling requirements. The system is fully tested and operational. 6) Formed a partnership with ASIAA in Taiwan, led by Tzu-Ching Chang who attended the original KISS study. ASIAA is providing major hardware components for the TIME-Pilot instrument, and in the past year have developed a prototype of the spectrometer, and procured cables and cryogenic coolers. ASIAA has also become the managing institution for the James Clerk Maxwell Telescope (JCMT) in Hawaii, and ideal facility for carrying out observations with the instrument