scholarly journals Ethanol Plant Location Determinants and County Comparative Advantage

2008 ◽  
Vol 40 (01) ◽  
pp. 117-135 ◽  
Author(s):  
D.M. Lambert ◽  
M. Wilcox ◽  
A. English ◽  
L. Stewart
Keyword(s):  
Comparative Advantage ◽  
Spatial Clustering ◽  
Clustering Methods ◽  
Probit Regression ◽  
Butyl Ether ◽  
Investment Activity ◽  
Tertiary Butyl ◽  
Excise Tax ◽  
Location Determinants ◽  
Input Markets

The location of ethanol plants is determined by infrastructure, product and input markets, fiscal attributes of local communities, and state and federal incentives. This empirical analysis uses probit regression along with spatial clustering methods to analyze investment activity of ethanol plants at the county level for the lower U.S. 48 states from 2000 to 2007. The availability of feedstock dominates the site selection decision. Other factors, such as access to navigable rivers or railroads, product markets, producer credit and excise tax exemptions, and methyl tertiary-butyl ether bans provided some counties with a comparative advantage in attracting ethanol plants.

APPLICATION OF IR SPECTROSCOPY IN THE STUDY OF MINERAL OIL

2017 ◽  
pp. 91-95
Author(s):  
E. I. Grushova ◽  
A. .. Al Razuqi ◽  
E. S. Chaiko ◽  
O. A. Miloserdova
Keyword(s):  
Ir Spectroscopy ◽  
Group Composition ◽  
Mineral Oil ◽  
Vacuum Distillate ◽  
Methyl Tertiary Butyl Ether ◽  
Butyl Ether ◽  
Tertiary Butyl ◽  
Mineral Oils ◽  
Modifying Additive

IR spectroscopy investigated structural and group composition of base mineral oils isolated from the vacuum distillate by selective purification of N-methylpyrrolidone and the low temperature dewaxing in the presence of a solvent. The role of the latter was carried out by the systems acetone - toluene, acetone - methyl tertiary butyl ether, methyl ethyl ketone - toluene, acetone - toluene - modifying additive. It was shown that the chemical composition of the group of base oils and slack waxes is defined as the nature of the solvent to the dewaxing, and oils sequence of purification steps.

scholarly journals Applicability Evaluation of Several Spatial Clustering Methods in Spatiotemporal Data Mining of Floating Car Trajectory

2021 ◽  
Vol 10 (3) ◽  
pp. 161
Author(s):  
Hao-xuan Chen ◽  
Fei Tao ◽  
Pei-long Ma ◽  
Li-na Gao ◽  
Tong Zhou
Keyword(s):  
Spatial Analysis ◽  
Spatial Clustering ◽  
Heat Index ◽  
Operating Efficiency ◽  
Clustering Methods ◽  
Clustering Method ◽  
Trajectory Mining ◽  
Density Peaks ◽  
Analysis Methods ◽  
Taxi Trajectory

Spatial analysis is an important means of mining floating car trajectory information, and clustering method and density analysis are common methods among them. The choice of the clustering method affects the accuracy and time efficiency of the analysis results. Therefore, clarifying the principles and characteristics of each method is the primary prerequisite for problem solving. Taking four representative spatial analysis methods—KMeans, Density-Based Spatial Clustering of Applications with Noise (DBSCAN), Clustering by Fast Search and Find of Density Peaks (CFSFDP), and Kernel Density Estimation (KDE)—as examples, combined with the hotspot spatiotemporal mining problem of taxi trajectory, through quantitative analysis and experimental verification, it is found that DBSCAN and KDE algorithms have strong hotspot discovery capabilities, but the heat regions’ shape of DBSCAN is found to be relatively more robust. DBSCAN and CFSFDP can achieve high spatial accuracy in calculating the entrance and exit position of a Point of Interest (POI). KDE and DBSCAN are more suitable for the classification of heat index. When the dataset scale is similar, KMeans has the highest operating efficiency, while CFSFDP and KDE are inferior. This paper resolves to a certain extent the lack of scientific basis for selecting spatial analysis methods in current research. The conclusions drawn in this paper can provide technical support and act as a reference for the selection of methods to solve the taxi trajectory mining problem.

scholarly journals Evidence for rapid avoidance of rockfish habitat under reduced quota and comprehensive at-sea monitoring in the British Columbia Pacific halibut fishery

2020 ◽  
Vol 77 (8) ◽  
pp. 1409-1420
Author(s):  
Robyn E. Forrest ◽  
Ian J. Stewart ◽  
Cole C. Monnahan ◽  
Katherine H. Bannar-Martin ◽  
Lisa C. Lacko
Keyword(s):  
British Columbia ◽  
Spatial Clustering ◽  
Clustering Methods ◽  
Quota System ◽  
Encounter Rates ◽  
System A ◽  
Pacific Halibut ◽  
Hippoglossus Stenolepis ◽  
Footprint Area ◽  
Management Changes

The British Columbia longline fishery for Pacific halibut (Hippoglossus stenolepis) has experienced important recent management changes, including the introduction of comprehensive electronic catch monitoring on all vessels; an integrated transferable quota system; a reduction in Pacific halibut quotas; and, beginning in 2016, sharp decreases in quota for yelloweye rockfish (Sebastes ruberrimus, an incidentally caught species). We describe this fishery before integration, after integration, and after the yelloweye rockfish quota reduction using spatial clustering methods to define discrete fishing opportunities. We calculate the relative utilization of these fishing opportunities and their overlap with areas with high encounter rates of yelloweye rockfish during each of the three periods. The spatial footprint (area fished) increased before integration, then decreased after integration. Each period showed shifts in utilization among four large fishing areas. Immediately after the reductions in yelloweye rockfish quota, fishing opportunities with high encounter rates of yelloweye rockfish had significantly lower utilization than areas with low encounter rates, implying rapid avoidance behaviour.

The Effect of Adding Oxygenated Compounds to Gasoline on Automotive Exhaust Emissions

2002 ◽  
Vol 125 (1) ◽  
pp. 344-350 ◽  
Author(s):  
S. G. Poulopoulos ◽  
C. J. Philippopoulos
Keyword(s):  
Octane Number ◽  
Combustion Engine ◽  
Methyl Tertiary Butyl Ether ◽  
Butyl Ether ◽  
Tertiary Butyl ◽  
Research Octane Number ◽  
Oxygenated Compounds ◽  
Reid Vapor Pressure ◽  
Three Way Catalyst ◽  
Unregulated Emissions

In the present work, the effect of adding ethanol or methyl tertiary butyl ether (MTBE) to gasoline on the regulated and unregulated emissions from an internal combustion engine with a typical three-way catalyst was studied. The addition of ethanol to fuel (10% w/w) increased both the research octane number and the Reid vapor pressure of the fuel, whereas adding 11% w/w MTBE caused an increase only in the research octane number of the fuel. When the fuel contained MTBE, less hydrocarbons, carbon monoxide, and acetaldehyde were emitted in the tailpipe. The increased emissions of acetaldehyde and ethanol were the main disadvantages of using ethanol.

scholarly journals Can We Protect Everybody from Drinking Water Contaminants?

2002 ◽  
Vol 21 (5) ◽  
pp. 389-395 ◽  
Author(s):  
Robert A. Howd
Keyword(s):  
Drinking Water ◽  
The Elderly ◽  
Butyl Ether ◽  
Water Contaminants ◽  
Tertiary Butyl ◽  
Health Goals ◽  
Fuel Tanks ◽  
Beneficial Uses ◽  
Alkyl Benzenes

Dozens of chemicals, both natural and manmade, are often found in drinking water. Some, such as the natural contaminants uranium and arsenic, are well-known toxicants with a large toxicology database. Other chemicals, such as methyl tertiary-butyl ether (MTBE) from leaking fuel tanks, we learn about as we go along. For still others, such as the alkyl benzenes, there are very little available data, and few prospects of obtaining more. In some cases, chemicals are purposely added to drinking water for beneficial purposes (e.g., chlorine, fluoride, alum), which may cause a countervailing hazard. Removing all potentially toxic chemicals from the water is virtually impossible and is precluded for beneficial uses and for economic reasons. Determination of safe levels of chemicals in drinking water merges the available toxicity data with exposure and human effect assumptions into detailed hazard assessments. This process should incorporate as much conservatism as is needed to allow for uncertainty in the toxicity and exposure estimates. Possible sensitive subpopulations such as unborn children, infants, the elderly, and those with common diseases such as impaired kidney function must also be considered. However, the range of sensitivity and the variability of toxicity and exposure parameters can never be fully documented. In addition, the validity of the low-dose extrapolations, and whether the toxic effect found in animals occurs at all in humans, is never clear. This publication discusses how these competing needs and uncertainties intersect in the development of Public Health Goals for uranium, fluoride, arsenic, perchlorate, and other highly debated chemicals.

Remediation of MTBE-contaminated groundwater by integrated circulation wells and advanced oxidation technologies

2017 ◽  
Vol 18 (2) ◽  
pp. 399-407 ◽  
Author(s):  
Bassam Tawabini ◽  
Mohammed Makkawi
Keyword(s):  
Groundwater Remediation ◽  
Treatment Time ◽  
Shallow Groundwater ◽  
Advanced Oxidation ◽  
Shallow Aquifer ◽  
Contaminated Groundwater ◽  
Butyl Ether ◽  
Tertiary Butyl ◽  
Industrial Facilities ◽  
Environmental Threats

Abstract The proximity of shallow groundwater systems to sources of contamination usually exposes them to severe environmental threats. Hazardous pollutants that leak from gas stations, landfills, and industrial facilities may eventually reach the underneath shallow groundwater aquifers, posing risks to human health and the environment. Cleaning contaminated groundwater sources has always been a challenge to the local authorities. This is even more challenging when dealing with difficult pollutants such as methyl tertiary butyl ether (MTBE) due its high solubility in water, poor biodegradability, and poor adsorption onto solids. This study aims to assess the efficiency of a pilot groundwater remediation system to treat a shallow aquifer contaminated with MTBE. The in-house designed and fabricated pilot system combines the technology of circulation wells and UV-based advanced oxidation technology for the breakdown and removal of MTBE from water. An ultraviolet/hydrogen peroxide (UV/H2O2) process was used in this study to remove MTBE from water. The concentration of MTBE was reduced from approximately 1,400 μg/L to as low as 34 μg/L within 30 minutes, with a treatment efficiency of about 98%. The study also assesses the effects of the UV intensity and the treatment time needed to remove the target pollutant.

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