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Overcoming the Challenges to the Implementation of Green Chemistry
The Harvard-Yale-ACS GCI Green Chemistry Project is investigating the overall question of the circumstances under which firms can enact innovations that have both economic and environmental benefits, through a focused examination of the implementation of green chemistry. The research project has taken up three fundamental, interrelated questions: What factors act as barriers to the implementation of green chemistry? What actions can be taken by the government, academia, NGO’s and industry that will help alleviate these factors? What are the policy implications of these barriers and potential actions, for all of the involved stakeholders?
During its initial phases, through interviews with a dozen green chemistry leaders from industry and academia, and through a multi-stakeholder workshop, the project has focused on the first two questions, and is working towards the third. Overall, we determined that there are six major classes of barriers to the implementation of green chemistry: economic, regulatory, technical, organizational, cultural and definition and metrics. From the workshop participants, six major action themes emerged to address these. They are: create incentives for the development and implementation of innovations; consider policies to shift focus to hazard reduction; facilitate linkages, networks and collaborations; act as a facilitator for multi-stakeholder initiatives; promote actions that make environmental and health impacts a larger part of the decision calculus; and support research, knowledge creation, and educational efforts to support green chemistry across a range of disciplines and problem areas
Synthesis of Semiochemicals via Olefin Metathesis
Semiochemicals are substances or mixtures that carry messages and are used for communication between individuals of the same or different species. Semiochemicals that are used in pest control are called biopesticides. Conventional pesticides, which are generally synthetically derived and unnatural, inactivate or kill the pests, whereas biopesticides are naturally occurring compounds that attract insects to a trap or interfere with their reproduction. There are several advantages to biopesticides. Compared with conventional pesticides, biochemical-based pesticides are often less toxic and therefore have a significantly lower impact on human health and the environment. Moreover, biopesticides are pest-selective and as such do not negatively impact other organisms such as insects, mammals, or birds. Other advantages of biopesticides include high potency, meaning that smaller amounts of biopesticide are required, less resistance by target organisms, and the ability to biodegrade more quickly than conventional pesticides. Although biochemical-based pesticides are very promising materials, their production is often cumbersome, and their application is often limited. To date, most biopesticides have been synthesized by multistep, classical organic reactions that are not economical and have high environmental impact. However, in recent decades many efforts have been made to implement cost-effective and safer chemical procedures for the widespread application of biochemical-based pesticides. The purpose of this Perspective is to draw the attention of the green chemistry community to the applicability of olefin metathesis reactions in environmentally benign and cost-effective biopesticide synthesis. We review seminal work on the total synthesis of biopesticides using olefin metathesis as a key reaction step, and in doing so, we hope to inspire new ideas for forthcoming olefin-metathesis-based biopesticide development
Synthesis of 1,6-hexandiol, polyurethane monomer derivatives via isomerization metathesis of methyl linolenate
Soft Templating and Disorder in an Applied 1D Cobalt Coordination Polymer Electrocatalyst
Disordered materials with resilient and soft-templated functional units bear the
potential to fill the pipeline of robust catalysts for renewable energy storage.
However, for novel materials lacking long-range order, the ability to discern
local structure with atomic resolution still pushes the boundaries of current
analytical and modeling approaches. We introduce a two-pillar strategy to
monitor the formation and unravel the structure of the first disordered onedimensional cobalt coordination polymer catalyst, Co-dppeO2. This target
material excels through proven high performance in commercial alkaline
electrolyzers and organic transformations. We demonstrate that the key architecture behind this activity is the unconventional embedding of hydrated
{H2O-Co2(OH)2-OH2} edge-site motifs, nested into a flexible organic matrix of
highly oxidized and bridging hydrophobic dppeO2 ligands. Our combination
of in situ spectroscopy and computational modeling of X-ray scattering and
absorption spectra, backed with complementary experimental techniques,
holds the key to understanding the atomic-range structure of important
disordered materials
The Changing Landscape for Stroke\ua0Prevention in AF: Findings From the GLORIA-AF Registry Phase 2
Background GLORIA-AF (Global Registry on Long-Term Oral Antithrombotic Treatment in Patients with Atrial Fibrillation) is a prospective, global registry program describing antithrombotic treatment patterns in patients with newly diagnosed nonvalvular atrial fibrillation at risk of stroke. Phase 2 began when dabigatran, the first non\u2013vitamin K antagonist oral anticoagulant (NOAC), became available. Objectives This study sought to describe phase 2 baseline data and compare these with the pre-NOAC era collected during phase 1. Methods During phase 2, 15,641 consenting patients were enrolled (November 2011 to December 2014); 15,092 were eligible. This pre-specified cross-sectional analysis describes eligible patients\u2019 baseline characteristics. Atrial fibrillation disease characteristics, medical outcomes, and concomitant diseases and medications were collected. Data were analyzed using descriptive statistics. Results Of the total patients, 45.5% were female; median age was 71 (interquartile range: 64, 78) years. Patients were from Europe (47.1%), North America (22.5%), Asia (20.3%), Latin America (6.0%), and the Middle East/Africa (4.0%). Most had high stroke risk (CHA2DS2-VASc [Congestive heart failure, Hypertension, Age 6575 years, Diabetes mellitus, previous Stroke, Vascular disease, Age 65 to 74 years, Sex category] score 652; 86.1%); 13.9% had moderate risk (CHA2DS2-VASc = 1). Overall, 79.9% received oral anticoagulants, of whom 47.6% received NOAC and 32.3% vitamin K antagonists (VKA); 12.1% received antiplatelet agents; 7.8% received no antithrombotic treatment. For comparison, the proportion of phase 1 patients (of N = 1,063 all eligible) prescribed VKA was 32.8%, acetylsalicylic acid 41.7%, and no therapy 20.2%. In Europe in phase 2, treatment with NOAC was more common than VKA (52.3% and 37.8%, respectively); 6.0% of patients received antiplatelet treatment; and 3.8% received no antithrombotic treatment. In North America, 52.1%, 26.2%, and 14.0% of patients received NOAC, VKA, and antiplatelet drugs, respectively; 7.5% received no antithrombotic treatment. NOAC use was less common in Asia (27.7%), where 27.5% of patients received VKA, 25.0% antiplatelet drugs, and 19.8% no antithrombotic treatment. Conclusions The baseline data from GLORIA-AF phase 2 demonstrate that in newly diagnosed nonvalvular atrial fibrillation patients, NOAC have been highly adopted into practice, becoming more frequently prescribed than VKA in Europe and North America. Worldwide, however, a large proportion of patients remain undertreated, particularly in Asia and North America. (Global Registry on Long-Term Oral Antithrombotic Treatment in Patients With Atrial Fibrillation [GLORIA-AF]; NCT01468701
Design for degradation or recycling for reuse?
In this perspective article, we discuss a point of conflict between circular economy and green chemistry due to, on the one hand, the need of recycling to fulfill a circular perspective and, on the other, to the concept of design for degradation. By presenting this approach, we aim to discuss the need to consider each process/material/technology from a holistic point of view that is able to embrace societal and economic aspects in addition to scientific impacts and results. In summary, considering the initial gap, we encouraged a new way to boost the interactions and synergies between these two elegant and internationally recognized approaches. We disclose how the design for degradation and circular economy in some cases can look in the same direction and how these concepts can contribute to realize the United Nations sustainable development goals
The Systemic Correlation Between Mental Models and Sustainable Design: Implications for Engineering Educators
Many studies have illuminated our understanding of the kinds of competencies and behaviors exhibited by effective designers. Against the backdrop of global challenges made more urgent by unintentional negative impacts of engineered products and systems, however, we are left to deduce that our ways of educating engineering designers is fundamentally flawed. We assert that one can trace the cause of our collective, unintended negative consequences to the mental models of reality that we consciously or unconsciously carry. In this paper, we present the case for developing awareness and facility with mental models. We also suggest an alternate mental model as the foundation for sustainable design. This model depicts reality as embedded systems of economies inside society and inside the environment. We also discuss how the engineering educator can use the model to build a foundation for holistically viewing design for sustainability. Student responses to a course based on the proposed ideas are also presented as evidence that students’ can value mental models and that working with them effectively changes their world conception
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