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The Oaxaca Clay Survey was initiated to provide baseline data on clay composition within the Valley of Oaxaca, Mexico, to assist in provenance determination of prehistoric ceramics. Natural clays were sampled from 135 locations throughout the valley, and analysed using INAA in combination with ceramic petrography. Observed geographical trends in trace‐element and mineralogical composition confirm that while parent material (surficial geology) strongly affects clay composition, a continuum of variation exists within the valley. The study develops and tests a continuous spatial model of clay composition that provides greater resolution in ceramic sourcing than bedrock alone. By establishing a regional framework for Oaxaca Valley clays, the survey will support significant advances in our understanding of pottery production and exchange within the valley, and provide a more robust means for monitoring exchange between the valley and neighbouring regions.

The Ford Nuclear Reactor operated from 1957 to 2003 on the University of Michigan's North Campus in Ann Arbor, Michigan. Over its 45-year lifespan, the facility played a key role in archaeometric research, fostering early methodological studies using INAA and supporting archaeological materials science investigations of lithics, ceramics, metals and bone. One small part of the FNR's abundant legacy was the initiation of trace-element studies of Oaxacan ceramics, which are now beginning to shed light on early exchange interactions and the origin of the Monte Albán state in the Valley of Oaxaca, Mexico, between 500 BCE and 200 CE .

and Zr. A substantial number of cases had values below detection limits for Ni, Sr, U, or Zr, and these elements were excluded from consideration. Element concentrations were transformed to log(10) values for statistical analyses. 2.2. Ceramic Petrography Petrographic analysis was conducted on a subset of 40 pottery thin sections representing the main ceramic composition groups and the full range of ceramic wares included in the study. Both qualitative and quantitative data were collected for each thin section using a standard petrographic microscope, following methods detailed in Minc and Sherman (2011). Qualitative analysis began with the identification of the overall suite of minerals evident in the thin section based on their optical properties under both plane-polarized and cross-polarized light. Quantitative data were collected using a point-counting technique similar to that described by Stoltman (1989, 1991). Using a movable stage, between 150 and 300 points were assessed within a grid of 1-mm intervals, and the point under the crosshairs recorded as matrix, void, or inclusion. If the crosshairs landed on an inclusion, the mineral was identified and the grain size recorded as silt (< .0624 mm), fine sand (.0625-.249 mm), medium sand (.25-.49 mm), coarse sand (.50-.99 mm), very coarse sand (1.00-1.99 mm), or gravel (> 2.00 mm) (following Stoltman, 1989:149, 1991:108). A grain size index based on an ordinal scale of 1 to 5 (fine = 1, medium = 2, coarse = 3, very coarse = 4, gravel = 5) was also calculated to represent the mean of the sand-and gravel-sized grains in each sample (Stoltman, 1991:108-109). 2.3. Assessing Temper vs. Natural Inclusions Determining whether mineral inclusions are naturally occurring or cultural additions has important implications for establishing provenance, since the addition of temper significantly modifies the trace-element and mineralogical signature of natural clays (Neff et al. 1988, 1989; Sterba et al. 2009). While it can be notoriously difficult to distinguish temper from natural inclusions, several lines of evidence have been proposed to identify cultural additions or mixing of clays. These include (1) the coexistence of minerals from distinct geological contexts; (2) a distinctive suite of minerals in the coarser sand-sized fraction as compared to the silt-and fine sand-sized fractions; and (3) the predominance of one size-class of inclusions, visible as a narrow unimodal or strongly bimodal size distribution within the sand-sized particles (

The crystal structures of benzotriazolylpropanamides are governed by π–π stacking between the benzotriazolyl residues and, in the case of primary amide NH2 groups, by N—H⋯O and N—H⋯N bridging.

In 1987, the Brundtland Report, "Our Common Future", produced the widely accepted definition of sustainable development as "meeting the needs of the present without compromising the ability of future generations to meet their own needs". But what can sustainability mean for the oil and gas industry, which produces fossil fuel required to meet basic human needs today such as food, fuel and shelter? The oil and gas industry provides a fundamental energy resource while improving health, reducing poverty, and increasing productivity for the global population. Oil and gas are therefore integral to promoting economic growth and will continue to play a major role in meeting the world's energy needs for the foreseeable future. Global energy policies are promoting low-carbon energy technologies, and the use of modern renewables will almost triple by 2035 to about 14% of total supply. However, renewables cannot satisfy global demand growth, so consumption of both oil and gas will also continue to grow.1 Oil and gas companies must therefore continue to discover, produce and supply these energy resources, and it is essential that they do so in a safe, environmentally sound and socially responsible manner. This requires safeguarding the environment; respecting the rights of others; protecting the health, safety and security of workers and the public; meeting increasingly stringent laws and regulations, and yet managing a range of operational, reputational and financial risks. An additional responsibility for companies is the need to communicate openly how they conduct their operations – the vision, decisions and strategies used to pursue resource developments. Sustainability reporting is therefore both a responsible and an expected method for companies to communicate publicly on environmental and social performance. The oil and gas industry has made significant progress on these objectives but challenges remain and individual companies need to tell their own sustainability stories in a clear, transparent, and honest manner. Finally, sustainability reporting also helps to establish a basis for continuous improvement in business processes and risk management. In particular, reporting has value for reputational risk, access to capital, and strengthened customer and employee relationships. For oil and gas companies, reporting can provide a robust platform for describing how strategic issues are being addressed through long-term plans and current initiatives. Stakeholders can now find details of a company's high level vision and strategy for dealing with sustainability-related impacts, implementing action plans and assessing outcomes on company websites and in annual reports.

Oil and gas oilwell service companies are currently under pressure from regulatory authorities, environmental groups, oil companies, stock holders, etc., to use "green" chemical products; however, at this time, there is no universally-accepted definition for "green."So how does a service company meet the requirement for using "green" chemical products, when "green" isn't defined?To meet the increasing demand for "green" chemical products, Halliburton has developed a system for scoring the hazards of chemical products.The Chemistry Scoring Index (CSI) is a method for quantifying the environmental, physical, and health properties of chemical products based on the hazards of its components. Each component of the product is scored in the three-hazard categories based on classification criteria from the United Nations' Globally Harmonized System for Classification and Labeling of Chemicals (GHS) and by additional hazard criteria developed by Halliburton. Each criterion is weighted as to its level of hazard (e.g., a carcinogen receives a higher weight (score) than an irritant). In addition, the score for a component is weighted on the percentage of the component in the product. The score for each component is added to give the product a score for each hazard category. The score from each hazard category is added together to compile a total score for the product. The lower the product score, the lower the Health, Safety, and Environmental (HSE) impact of the chemical product.The score for chemical products in the same usage type are compared to determine the best HSE chemical for the application. The scores are used to promote the use of more HSE responsible chemicals, to help in the development of less hazardous chemical products and to help prioritize products in the company's chemical portfolio. Use of the CSI helps reduce or eliminate hazardous chemicals that can harm human health, safety, and environment.