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Key Elements of Green Chemistry

Key Elements of Green Chemistry

I would be very remiss if I didn’t acknowledge my Class of 2016 that inspired me to put this living text together. It has made a world of difference to me because it has stimulated me to think and pose what I think is of value. I am deeply indebted to Dr. Medwick Byrd for his commitment to this class by his original suggestion back in 2011 and his constant support of my teaching efforts in class and in the laboratory. His sizeable support of a CEM microwave has lent this class a level of world- class stature in its content and substance to our NC State students. I am very grateful, as well, to Ms. Rachel Scroggins, who was part of my Fall 2015 class and one of my very best students and protégés. She has returned to help me TA our current crop of students and also develop new laboratory exercises. I would be remiss if I didn’t acknowledge that she received one of the most prestigious awards an undergraduate student can receive in the USA, the John J. McKetta Undergraduate Scholarship. I would also like to recognize my second home, the Chemistry Department, for their active support and input. Melinda Box, who coordinates our chemistry labs for the University, is a pleasure to work with. Drs. Feducia, Gallardo-Williams, and Neyhart have helped me in directing students to me and helping find TAs. A shout out to Dr. Lisa Bullard at Chemical & Biomolecular Engineering who has been so wonderfully involved in the course
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Phytoextraction as a tool for green chemistry

Phytoextraction as a tool for green chemistry

Abstract: The unique chemical and physical proper- ties of metals mean that they are extensively utilized by industry in a huge variety of applications, including electronics, materials, industrial catalysts and chemi- cals. The increased consumer demand from a growing population worldwide with rising aspirations for a better life has resulted in concerns over the security of supply and accessibility of these valuable elements. As such, there is a growing need to develop alternative meth- ods to recover them from waste repositories, current or historic, both for hazard avoidance and potentially, as a new source of metals for industry. Phytoextrac- tion (the use of plants for the recovery of metals from waste repositories) is a green and novel technique for metal recovery, which, if done with the goal of resource supply rather than hazard mitigation, is termed “phy- tomining”. The ability for plants to form metallic nan- oparticles as a consequence of phytoextraction could make the recovered metal ideally suited for utilization in green chemical technologies, such as catalysis. This review focuses on a multidisciplinary approach to ele- mental sustainability and highlights important aspects of metal lifecycle analysis, metal waste sources (includ- ing mine tailings), phytoextraction and potential green chemical applications that may result from the integra- tion of these approaches.
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Biological Chemistry The Core Promoter and Redox-sensitive Cis -elements as Key Targets for Inactivation of the Lysyl Oxidase Gene by Cadmium

Biological Chemistry The Core Promoter and Redox-sensitive Cis -elements as Key Targets for Inactivation of the Lysyl Oxidase Gene by Cadmium

Cadmium (Cd) is a toxic metal without any biological availability. In addition to occupational exposure, cigarette smoke constitutes a major source of Cd exposure for humans [2, 6]. Cd targets the lung with a biological half-life of 9.4 years inducing emphysema and cancers [6]. Previous studies have illustrated down-regulation of LOX by Cd at mRNA, protein and catalytic levels in lung cell and animal models [7, 8]. The gene cloning studies have shown the rat LOX gene promoter containing the Inr-DPE core promoter with multiple transcription start sites and several redox-sensitive cis-acting elements such as the NFI binding site, metal response element (MRE), antioxidant response element (ARE), etc. [9]. To further assess molecular basis for Cd damage to the lung LOX, we have studied Cd effects on the LOX promoter regulation using Cd resistant (CdR) lung cells as a chronic Cd exposure model.
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TRENDS OF GREEN CATALYSIS IN SYNTHETIC CHEMISTRY: AN OVERVIEW

TRENDS OF GREEN CATALYSIS IN SYNTHETIC CHEMISTRY: AN OVERVIEW

ABSTRACT: This paper is to review the green catalytic synthesis of organic reactions and discussed its advantages over the conventional method of synthesis. Recent advanced technologies have key trend to reduce the negative impacts of chemical environment and helps to obtain sustainability in chemical production. This review tries to bring many catalytic techniques that are safer in nature and more economical. We have considered those synthetic schemes which have significant role in pharmaceuticals industry and the different green catalyst employed in those reactions. These organic reactions have special advantages with the use of catalyst; there is better utilization of starting materials and minimum waste product formation. The main objective of these synthetic schemes is that there is least pollution to the environment.
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Green Chemistry - New Approach in Drug Synthesis

Green Chemistry - New Approach in Drug Synthesis

The green synthesis for a key intermediate of atorvastatin has been developed in two steps. First step involves the biocatalytic reduction of ethyl-4- chloroacetoacetate using a ketoreductase in combination with glucose and a NADP-dependent glucose dehydrogenase (GDH) for cofactor regeneration. The (S)ethyl-4-chloro-3-hydroxybutyrate product is obtained in very good yield. In the second step, a halohydrindehalogenase (HHDH) is employed to catalyze the replacement of the chloro substituent with cyano, by reaction with HCN at neutral pH and ambient temperatures. These natural enzymes were highly selective for the reactions. (16)
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SEVEN ELEMENTS BURGENLAND WINE KEY FACTS

SEVEN ELEMENTS BURGENLAND WINE KEY FACTS

What makes this region truly unique are its soils. The inclines at the very top of Eisenberg hill predominant- ly feature slate soils. Further down, the soils grow in- creasingly heavier. They may consist of oxidised green- schist, quartz phyllite, calcareous schist or serpentinite and are covered by a loam layer of varying thickness. Their common feature is a high content of iron, which produces particularly spicy Blaufränkisch wines with exceptional minerality. Local winemakers nowadays

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“Handbook of Green Chemistry – Green Catalysis”233-238

“Handbook of Green Chemistry – Green Catalysis”233-238

A key feature of green catalysis is that the catalysts themselves have to be green, which means that they need to be manufactured cleanly and sustainably, and to be recycled efficiently. Chapter 2 describes the use of silica-supported sulfonic acids as a green alter- native to concentrated sulfuric acid in liquid-phase organic syntheses. In a similar vein, the issues relat- ing to the separation of catalyst and product during homogeneous catalysis can be overcome by design- ing single-site heterogeneous catalysts in which organometallic complexes are grafted onto a metal oxide support (Chapter 6). This degree of control over the active site is also becoming more prevalent in conventional heterogeneous catalysis (Chapter 4), where our ability to create metal nanoparticles con- sistently and within a pre-defined size range has led to step-changes in activity and selectivity.
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KEY ELEMENTS OF SHIPPING

KEY ELEMENTS OF SHIPPING

The participants will understand the roles of the many shipping industry “players”, the regulatory complexities of ship owning and management, the intricacies of ship acquisition and finance, shipping economics and market cycles, chartering fundamentals and revenue projection, risk management and marine insurance and the challenges and opportunities of green shipping. Learning assessment will be by way of case studies and Q & A sessions and a BI Norwegian Business School “Certificate of Achievement” will be awarded. The outcome is that the course will enhance the knowledge, confidence and credentials of the participants to enable them to advance their careers in one of the world’s most challenging industries.
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Chemistry on the inside: green chemistry in mesoporous materials

Chemistry on the inside: green chemistry in mesoporous materials

The initial applications of MCMs were, perhaps not surprisingly, simply attempts to reproduce zeolite chemistry on larger molecules. This chemistry is based on the fact that the aluminium centres in zeolites cause a negative charge to exist on the framework of the solid; this charge must be balanced by a cation. When the cation is a proton, the material is an acid, and some zeolites are very strong acids indeed. However, the acidity of the corresponding MCMs is considerably lower, and this has limited their applicability somewhat. Nevertheless, the MCMs are often very e¬ective as mild acid catalysts. Much work has therefore been aimed at the production of other materials using the same concept, but with either di¬erent templating systems, or with combinations of elements other than Si and Al in the framework.
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To Study the Current Status, and Future Challenges of Green Chemistry

To Study the Current Status, and Future Challenges of Green Chemistry

Significant progress of methodological green chemistry is being made in several key research areas, such as catalysis, the design of safer chemicals and environmentally benign solvents, and the development of renewable feedstocks. Current and future chemists are being trained to design products and processes with an increased awareness for environmental impact. Outreach activities within the green chemistry community highlight the potential for chemistry to solve many of the global environmental challenges we now face.
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Green chemistry: carbon-bearing minerals as a source of nanocarbons

Green chemistry: carbon-bearing minerals as a source of nanocarbons

Carbon is one of the most important elements in the world as it builds both organic and inorganic matter. Till XX century only two allotropes of carbon were known, graphite and diamond (in addition to amorphous carbon, i.e. soot or carbon black). Recent decades brought into a daylight, however, new nanocarbon allotropes 1 . In 1985 the fullerenes were discovered 2 , with the importance of the discovery honored with a Nobel Price (1996). Soon later, carbon nanotubes (even called the ‘black diamonds of XX century’) were shown to the world (1991) 3 . The very beginning of the XXI century brought one, even more important discovery of next new carbon allotrope – graphene 4 . Graphene and graphene-related nanomaterials are indeed a revolutionary materials. They have many applications replacing conventional materials as well as the ability to support applications previously not possible before the advent of two- dimensional materials. The applications of graphene are truly endless and many are yet to be conceived of 5 .
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Review of 12 Principles of Green Chemistry in Practice

Review of 12 Principles of Green Chemistry in Practice

stage of science progress it is unrealistic to expect that in the next ten years a wide application of ionic liquids will be seen. Although, as is well known, ionic liquids are slightly volatile due to the low vapor pressure, yet it is only one of the many things that make a substance really green. For example, ion- based, imidazole-based and fluoro-anion-based liquids are likely to be poisonous but can not reach the environment by evaporation. The problem is that most ionic liquids are water- soluble and can easily reach the biosphere through that pathway [24].

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 GREEN CHEMISTRY POTENTIAL FOR PAST, PRESENT AND FUTURE PERSPECTIVES

 GREEN CHEMISTRY POTENTIAL FOR PAST, PRESENT AND FUTURE PERSPECTIVES

Chemistry brought about medical revolution till about the middle of twentieth century in which drugs and antibiotics were discovered. The world’s food supply also increased enormously due to the discovery of hybrid varieties, improved methods of farming, better seeds, and use of insecticides, herbicides and fertilizers. The quality of life on earth became much better due to the discovery of dyes, plastics, cosmetics and other materials. Soon, the ill effects of chemistry also became pronounced, main among them being the pollution of land, water and atmosphere. This is caused mainly due to the effects of by- products of chemical industries, which are being discharged into the air, rivers/ oceans and the land. The use of toxic reactants and reagents also make the situation worse. The pollution reached such levels that different governments made laws to minimize it. This marked the beginning of Green Chemistry by the middle of 29 th century. Green Chemistry is defined as environmentally benign chemistry. As on today, maximum pollution to the environment is caused by
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Key Elements of a Uniform Organizational Culture

Key Elements of a Uniform Organizational Culture

Det kommer tydelig frem at informantene mener kulturen bør være i tråd med mål, strategi, handlinger og organisering, eller så vil ikke kulturen være til noen nytte, slik informanten f[r]

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Green chemistry approach for the synthesis of biocompatible graphene

Green chemistry approach for the synthesis of biocompatible graphene

Background: Graphene is a single-atom thick, two-dimensional sheet of hexagonally arranged carbon atoms isolated from its three-dimensional parent material, graphite. One of the most common methods for preparation of graphene is chemical exfoliation of graphite using powerful oxidizing agents. Generally, graphene is synthesized through deoxygenation of graphene oxide (GO) by using hydrazine, which is one of the most widespread and strongest reducing agents. Due to the high toxicity of hydrazine, it is not a promising reducing agent in large-scale production of graphene; therefore, this study focused on a green or sustainable synthesis of graphene and the biocompatibility of graphene in primary mouse embryonic fibroblast cells (PMEFs). Methods: Here, we demonstrated a simple, rapid, and green chemistry approach for the synthesis of reduced GO (rGO) from GO using triethylamine (TEA) as a reducing agent and stabilizing agent. The obtained TEA reduced GO (TEA-rGO) was characterized by ultraviolet (UV)–visible absorp- tion spectroscopy, X-ray diffraction (XRD), particle size dynamic light scattering (DLS), scanning electron microscopy (SEM), Raman spectroscopy, and atomic force microscopy (AFM). Results: The transition of graphene oxide to graphene was confirmed by UV–visible spectroscopy. XRD and SEM were used to investigate the crystallinity of graphene and the sur- face morphologies of prepared graphene respectively. The formation of defects further supports the functionalization of graphene as indicated in the Raman spectrum of TEA-rGO. Surface morphology and the thickness of the GO and TEA-rGO were analyzed using AFM. The pre- sented results suggest that TEA-rGO shows significantly more biocompatibility with PMEFs cells than GO.
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The Six Key Elements Of Proactive Chat

The Six Key Elements Of Proactive Chat

■ Need critical help in the middle of online purchases. Fifty-five percent of US online adults are likely to abandon their online purchase if they cannot find a quick answer to their question (see Figure 1). Shopping cart, site visit, and application abandonment rates have plagued companies for decades. Leaving customers with key questions unanswered in the process of making a purchase or applying for a service is practically the equivalent of providing them with a link to your competitor’s site.

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Key Elements of Highly Effective Teams

Key Elements of Highly Effective Teams

Sometimes things do not work well. For instance, the team may not func- tion well, the team may not have been set up for success, or external events may have derailed the team ’ s prog- ress. To fi nd out what went wrong, a team should ask the following questions based on the 3 key ele- ments described in this article:

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Green Synthesis of Benzimidazole Derivatives: an Overview on Green Chemistry and Its Applications

Green Synthesis of Benzimidazole Derivatives: an Overview on Green Chemistry and Its Applications

In current years, various reports which were related to synthesis of nitrogen (N), oxygen (O) and Sulphur (S) containing heterocyclic had appeared owing to an extensive variety of their pharmacological activities. In recent years, numerous reports concerning the synthesis of heterocyclic compounds under various conditions like solvent-free, reactants immobilized on a solid support, microwave (MW) irradiation condition, green catalyst, and green solvent have appeared. Benzimidazole is a heterocyclic aromatic organic compound. It is a pharmacophore and a privileged structure in medicinal chemistry. This compound which is bicyclic consists of the fusion of benzene (1) and imidazole (2) also known as benzimidazole (3) (Scheme 1).
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A green chemistry approach for synthesizing biocompatible gold nanoparticles

A green chemistry approach for synthesizing biocompatible gold nanoparticles

In most studies, either AuNPs or AgNPs were synthe- sized using bacteria. Many fungi have not been explored, including those mentioned above, and only a few fungi have been investigated for AuNP and AgNP synthesis. Among fungi that have not been tested, Ganoderma spp. have long been used as medicinal mushrooms in Asia, and they have an array of pharmacological properties, in- cluding immunomodulatory activity and pharmacological properties [39]. Ganoderma spp. have several advantages: They have large quantities of viable mycelia, they are cost- effective, there is easy downstream processing, and they are non-pathogenic. Moreover, the synthesized AuNPs are highly soluble in water. Therefore, the aim of this study was to investigate the possible use of Ganoderma spp. as green producers for AuNP synthesis and to further evalu- ate the biocompatibility effect of as-prepared AuNPs in human breast cancer cells (MDA-MB-231).
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Advances in analytical microextraction methods towards green chemistry

Advances in analytical microextraction methods towards green chemistry

Where a solvent must be used, water is, without doubt, the most acceptable in terms of cost and environmental impact. However, despite its large liquid range and extremely high specific heat capacity, it is frequently overlooked as a solvent for organic reactions, perhaps because of a misplaced belief that organic reactions must require an organic solvent. All of these issues were used to improve a method of analytical to green chemistry. Lately, basic of green chemistry has become an interesting topic for discussion and debate that used for researchers [1-3].
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