ANALYSES OF DENSELY CROSSLINKED PHENOLIC SYSTEMS USING LOW FIELD NMR

A uniform dispersion of reactants is necessary to achieve a complete reaction involving multi-components, especially for the crosslinking of rigid high-performance materials. In these reactions, miscibility is crucial for curing efficiency. This miscibility is typically enhanced by adding a third component, a plasticizer. For the reaction of the highly crystalline crosslinking agent hexamethylenetetramine (HMTA) with a strongly hydrogen-bonded phenol formaldehyde resin, furfural has been traditionally used as the plasticizer. However, the reason for its effectiveness is not clear. In this doctoral thesis work, miscibility and crosslinking efficiency of plasticizers in phenolic curing reactions are studied by thermal analysis and spectroscopic methods to elucidate the role of furfural. By combining information from NMR, infrared spectroscopy and differential scanning calorimetry, we show that the presence of furfural increases segmental mobility, disrupts the hydrogen-bonded matrix and frees the hydroxyl units, which further increases HMTA solubility. The higher solubility and segmental mobility increases the extent of crosslinking in the phenolic system. Extent of crosslinking is determined from the spin lattice relaxation time T1 measured by low field NMR (LFNMR). We demonstrate the effectiveness of this method for phenolic systems, where others methods like infrared spectroscopy and differential scanning calorimetry are inappropriate. For validation, we have also correlated extent of crosslinking with T1 using epoxy. The utilization of LFNMR in this work demonstrates its value for characterizing crosslinking of rigid thermosets. Two alternative plasticizers to furfural are substituted in these phenolic curing reactions because of their environmental friendliness: the non-reactive methyl benzoate and the reactive methyl anthranilate. Their effect on the extent of crosslinking is evaluated and compared with the traditional reactive plasticizers furfuryl alcohol and furfural

Investigation of Methods for Gravity Pipelines Inspection

This paper investigates the methods used for gravity pipe inspection. However, a discussion of pipe inspection methods cannot truly happen without and understanding of the preliminary process of pipe prioritization. This is because the vast amount of just gravity pipeline system in use today. For instance, the amount of time, money and resources to aimlessly inspect all suspected pipelines in India alone would be astronomical. So, presented here is a reason why the employment of algorithms and analysis tools must be used to priorities the pipeline systems to see which one need inspection for further analysis. The study goes on to describe innovative techniques used for pipe inspection itself and what kind of innovations should have more attention such as wave and sound analysis that allow for greater inspection rates. This research gives a brief overview of the process of pipe inspection and aspect of cost saving algorithms that can allow more efficiency to enter the field

Using Decision-making Criteria Approach for the Selection of Trenchless Construction Method: A Review Study

Trenchless technologies (TTs) are used to install new pipes or repair and replace the old pipes classified in two categories: construction and rehabilitation/ replacement methods. Due to rapid urbanization, new pipe network should be established proportional to the population growth. On other hand, due to issues such as corrosion and aging, a major part of storm sewer, waste sewer, gas, water pipes must be replaced/ rehabilitated every year. Traditional open-cut methods are not applicable anymore disruption to traffic, unsafety, environmental impacts, high cost and so on while the trenchless construction methods are able to address these issues. The construction trenchless methods include horizontal earth boring (no worker entry), pipe jacking and utility tunneling (worker entry). The first one is subcategorized to horizontal auger boring, horizontal directional drilling, pipe ramming, microtunneling, pilot tube microtunneling and compaction method. In the first part of the current study, the design criteria needed for horizontal auger boring, horizontal directional drilling, pipe jacking, pipe ramming and micro tunneling will be reviewed and discussed. Considering these requirements which are unique for each individual project, the optimum trenchless technology can be proposed for that project. In the second part of this research, based on a concept given in the literature, a hierarchical algorithm is proposed by the author that is defined based on the design requirements and can be used as a decision-making tool to select an optimum trenchless construction method. Sometimes more than one method can be proposed. The best one will be selected based on availability of equipment and skillful team, budget and sustainability principles. Although the trenchless renewal methods are not in the scope of the present study, their respective design criteria are given in the appendices in order to provide a complete collection of design requirements for the all trenchless technologies

A Comprehensive Study on Present State of Underground Pipeline Infrastructure in Developed Countries

This paper provides a comprehensive overview of existing state of underground pipelines in developed countries like the United States (US) and focus on history, performance, and barriers to long-term planning. Most of the pipeline infrastructure construction in the United States was done in 1950’s and 1960’s due to population and economic growth (Najafi, 2005). The Pipelines built during this period were by using cast iron and steel material.  The Pipes that are buried during this period are more than 70 years old, which needs to be replaced / renewed. According to ASCE 2017 Infrastructure report card, water and the wastewater pipelines received a grade D and D+ respectively, which states that there is a significant need in improving these infrastructure conditions. The main objective of this paper is to provide an overview of underground pipeline infrastructure in the developed countries with focus on the US. To study pipelines construction or renewal which is been done by traditional open-cut method or latest Trenchless technology. The scope of this paper is limited to water, wastewater and liquid and gas transmission pipeline infrastructure of underground utilities in the United States. The methodology of this paper discusses about the infrastructure needed for the operation and maintenance of pipeline infrastructure, the construction and renewal of the pipelines using traditional open-cut and Trenchless technology methods, the risks associated in constructing, renewing and operating the pipelines. It can be concluded, that the present scenario of water, wastewater, liquid and gas transmission pipelines are not meeting the required standards. This problem can be addressed through strategic planning for the nation’s economic and overall developmen

The biology of lysine acetylation integrates transcriptional programming and metabolism

<p>Abstract</p> <p>The biochemical landscape of lysine acetylation has expanded from a small number of proteins in the nucleus to a multitude of proteins in the cytoplasm. Since the first report confirming acetylation of the tumor suppressor protein p53 by a lysine acetyltransferase (KAT), there has been a surge in the identification of new, non-histone targets of KATs. Added to the known substrates of KATs are metabolic enzymes, cytoskeletal proteins, molecular chaperones, ribosomal proteins and nuclear import factors. Emerging studies demonstrate that no fewer than 2000 proteins in any particular cell type may undergo lysine acetylation. As described in this review, our analyses of cellular acetylated proteins using DAVID 6.7 bioinformatics resources have facilitated organization of acetylated proteins into functional clusters integral to cell signaling, the stress response, proteolysis, apoptosis, metabolism, and neuronal development. In addition, these clusters also depict association of acetylated proteins with human diseases. These findings not only support lysine acetylation as a widespread cellular phenomenon, but also impel questions to clarify the underlying molecular and cellular mechanisms governing target selectivity by KATs. Present challenges are to understand the molecular basis for the overlapping roles of KAT-containing co-activators, to differentiate between global versus dynamic acetylation marks, and to elucidate the physiological roles of acetylated proteins in biochemical pathways. In addition to discussing the cellular 'acetylome', a focus of this work is to present the widespread and dynamic nature of lysine acetylation and highlight the nexus that exists between epigenetic-directed transcriptional regulation and metabolism.</p

Non-clinical safety evaluation of a novel pharmaceutical salt, rosuvastatin ethanolamine, in Wistar rats

Rosuvastatin, a second generation 3-Hydroxy-3-Methyl Glutaryl Coenzyme-A reductase inhibitor, is widely used for the management of hypercholesterolemia. Rosuvastatin ethanolamine, developed by Cadila Healthcare Ltd., is a novel, chemically stable, and pharmaceutically acceptable salt, having better physiochemical properties than commercially available Rosuvastatin salt. The objective of the present study is to evaluate safety, tolerability, and toxicokinetic profile of novel salt. Therefore, four weeks repeated dose oral (gavage) toxicity and toxicokinetic study of Rosuvastatin ethanolamine was carried out. The drugs were administered once daily at salt corrected dose of 15, 40, and 100 mg/kg for four weeks. No signs of toxicity were observed during repeated (four weeks) oral administrations of Rosuvastatin ethanolamine in rats up to 40 mg/kg. Single male mortality was observed at 100 mg/kg dose. Microscopy finding in liver was minimal to mild bile ductular proliferation, single cell necrosis, and hepatocellular vacuolation of cytoplasm with associated statistically significant serum elevation of transaminase enzymes; AST, ALT, ALP, and/or liver functional marker; total bilirubin with at ≥40 mg/kg. The systemic exposures (AUC0–24 and Cmax) were not markedly different between males and females, or between the administration periods (except high dose, where exposure on day 28 was approximately 2 to 3 fold higher than that of day 1. In conclusion, Rosuvastatin ethanolamine exhibited toxicities to liver as the target organ at ≥40 mg/kg in this study. These adverse effects with associated exposures should be taken into consideration for the future assessing of potential Rosuvastatin toxicities

Diversity of intertidal, epibiotic, and fouling barnacles (Cirripedia, Thoracica) from Gujarat, northwest India

The present work studied the diversity of intertidal, epibiotic, and fouling barnacles in the state of Gujarat, northwest India. In total, eleven species belonging to eight genera and five families were recorded in the present study. The Arabian intertidal species Tetraclita ehsani Shahdadi, Chan &amp;amp; Sari, 2011 and Chthamalus barnesi Achituv &amp;amp; Safriel, 1980 are common in the high- and mid-intertidal rocky shores of Gujarat suggesting that the Gujarat barnacle assemblages are similar to the assemblages in the Gulf of Oman Ecoregion. The biogeographical boundary between the Gulf of Oman and Western Indian ecoregions for barnacles should probably extend southward towards the waters adjacent to Mumbai, where Indo-Pacific species of intertidal barnacles dominate. This study provides the first reports of the common widely distributed balanomorph barnacles Striatobalanus tenuis (Hoek, 1883), Tetraclitella karandei Ross, 1971, Amphibalanus reticulatus (Utinomi, 1967), and lepadid barnacle Lepas anatifera Linnaeus, 1758 in Gujarat, as well as of the chthamalid barnacle Chthamalus barnesi in India

Annotated Checklist of Marine Amphipods (Crustacea: Amphipoda) of India

Thacker, Dimple, Patel, Krupal, Myers, Alan, Guerra-García, José M., Zeidler, Wolfgang, Trivedi, Jigneshkumar (2023): Annotated Checklist of Marine Amphipods (Crustacea: Amphipoda) of India. Zootaxa 5340 (1): 1-90, DOI: 10.11646/zootaxa.5340.1.1, URL: http://dx.doi.org/10.11646/zootaxa.5340.1.