Atmospheric Oxidation of Piperazine Initiated by OH: A Theoretical Kinetics Investigation

10.26434/chemrxiv.9198158.v1 ◽

2019 ◽

Author(s):

Zhonghua Ren ◽

Gabriel da Silva

Keyword(s):

Carbon Capture ◽

First Generation ◽

Peroxyl Radical ◽

Capture Rate ◽

Oxidation Products ◽

Subsequent Reaction ◽

Alkoxyl Radical ◽

Cyclic Amide ◽

A Minor ◽

The Impact

Piperazine (Pz) mixed with other amines is a proposed carbon capture solvent, but there is concern about the impact of Pz on air quality, including the potential to produce toxic products. Here, the •OH initiated oxidation of Pz has been studied by ab initio modelling and RRKM / master equation kinetic simulations. The Pz + •OH reaction is found to proceed at around the capture rate, consistent with experiment, with abstraction predominantly from C—H sites. The subsequent reaction kinetics of carbon centred Pz radicals with O2 are also studied, so as to determine the first-generation oxidation products. We find that the Pz radical predominantly reacts with O2 to produce a cyclic imine product + HO2• under tropospheric conditions, with the stabilized peroxyl radical formed as a minor product. Subsequent reaction of the peroxyl radical with NO produces an alkoxyl radical that can react with O2 to yield a cyclic amide or undergo unimolecular ring opening followed by a second O2 addition / HO2• elimination step to produce CH2=NCH2CH2NHCHO.<br>

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Rapid evaluation of FDG imaging alternatives using head-to-head comparisons of full ring and gamma camera based PET scanners –

Nuklearmedizin ◽

10.1055/s-0038-1625288 ◽

2002 ◽

Vol 41 (05) ◽

pp. 208-213 ◽

Cited By ~ 1

Author(s):

L. M. Haslinghuis-Bajan ◽

L. Hooft ◽

A. van Lingen ◽

M. van Tulder ◽

W. Devillé ◽

...

Keyword(s):

Methodological Quality ◽

Gamma Camera ◽

First Generation ◽

Prospective Evaluation ◽

First Approximation ◽

Variable Head ◽

Malignant Lesions ◽

The Impact ◽

Pet Scanners

SummaryAim: While FDG full ring PET (FRPET) has been gradually accepted in oncology, the role of the cheaper gamma camera based alternatives (GCPET) is less clear. Since technology is evolving rapidly, “tracker trials” would be most helpful to provide a first approximation of the relative merits of these alternatives. As difference in scanner sensitivity is the key variable, head-to-head comparison with FRPET is an attractive study design. This systematic review summarises such studies. Methods: Nine studies were identified until July 1, 2000. Two observers assessed the methodological quality (Cochrane criteria), and extracted data. Results: The studies comprised a variety of tumours and indications. The reported GC- and FRPET agreement for detection of malignant lesions ranged from 55 to 100%, but with methodological limitations (blinding, standardisation, limited patient spectrum). Mean lesion diameter was 2.9 cm (SD 1.8), with only about 20% <1.5 cm. The 3 studies with the highest quality reported concordances of 74-79%, for the studied lesion spectrum. Contrast at GCPET was lower than that of FRPET, contrast and detection agreement were positively related. Logistic regression analysis suggested that pre-test indicators might be used to predict FRPET-GCPET concordance. Conclusion: In spite of methodological limitations, “first generation” GCPET devices detected sufficient FRPET positive lesions to allow prospective evaluation in clinical situations where the impact of FRPET is not confined to detection of small lesions (<1.5 cm). The efficiency of head-to-head comparative studies would benefit from application in a clinically relevant patient spectrum, with proper blinding and standardisation of acquisition procedures.

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The Famous Forty and Their Companions: North Yemen's First-Generation Modernists and Educational Emigrants

The Middle East Journal ◽

10.3751/59.1.15 ◽

2005 ◽

Vol 59 (1) ◽

pp. 81-97 ◽

Cited By ~ 1

Author(s):

Robert D. Burrowes

Keyword(s):

First Generation ◽

The Political ◽

Major Conclusion ◽

Political Structure ◽

Cultural System ◽

The Impact

This article is a study of the several hundred North Yemenis who went out from isolated Yemen for education between 1947 and 1959. It focuses on their backgrounds, what and where they studied, the impact on them of this experience, what they did when they returned and, finally, the impact they have had on the Yemen most hoped to change. The major conclusion is that their impact has been modest and that this is best explained by Yemen's socio-cultural system and the political structure it supports.

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Law and Economics

The Oxford Handbook of the New Private Law ◽

10.1093/oxfordhb/9780190919665.013.6 ◽

2020 ◽

pp. 84-102

Author(s):

Daniel B. Kelly

Keyword(s):

Economic Analysis ◽

First Generation ◽

Law And Economics ◽

Private Law ◽

Foreseeable Future ◽

Business Associations ◽

The Third ◽

Starting Point ◽

The Law ◽

The Impact

This chapter analyzes how law and economics influences private law and how (new) private law is influencing law and economics. It focuses on three generation or “waves” within law and economics and how they approach private law. In the first generation, many scholars took the law as a starting point and attempted to use economic insights to explain, justify, or reform legal doctrines, institutions, and structures. In the second generation, the “law” at times became secondary, with more focus on theory and less focus on doctrines, institutions, and structures. But this generation also relied increasingly on empirical analysis. In the third generation, which includes scholars in the New Private Law (NPL), there has been a resurgence of interest in the law and legal institutions. To be sure, NPL scholars analyze the law using various approaches, with some more and some less predisposed to economic analysis. However, economic analysis will continue to be a major force on private law, including the New Private Law, for the foreseeable future. The chapter considers three foundational private law areas: property, contracts, and torts. For each area, it discusses the major ideas that economic analysis has contributed to private law, and surveys contributions of the NPL. The chapter also looks at the impact of law and economics on advanced private law areas, such as business associations, trusts and estates, and intellectual property.

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Experimental study of the supercritical CO 2 diffusion coefficient in porous media under reservoir conditions

Royal Society Open Science ◽

10.1098/rsos.181902 ◽

2019 ◽

Vol 6 (6) ◽

pp. 181902 ◽

Cited By ~ 1

Author(s):

Junchen Lv ◽

Yuan Chi ◽

Changzhong Zhao ◽

Yi Zhang ◽

Hailin Mu

Keyword(s):

Porous Media ◽

Diffusion Coefficient ◽

Oil Recovery ◽

Carbon Capture ◽

Carbon Capture And Storage ◽

Elevated Pressure ◽

Experimental Results ◽

Saturated Porous Media ◽

Reservoir Conditions ◽

The Impact

Reliable measurement of the CO 2 diffusion coefficient in consolidated oil-saturated porous media is critical for the design and performance of CO 2 -enhanced oil recovery (EOR) and carbon capture and storage (CCS) projects. A thorough experimental investigation of the supercritical CO 2 diffusion in n -decane-saturated Berea cores with permeabilities of 50 and 100 mD was conducted in this study at elevated pressure (10–25 MPa) and temperature (333.15–373.15 K), which simulated actual reservoir conditions. The supercritical CO 2 diffusion coefficients in the Berea cores were calculated by a model appropriate for diffusion in porous media based on Fick's Law. The results show that the supercritical CO 2 diffusion coefficient increases as the pressure, temperature and permeability increase. The supercritical CO 2 diffusion coefficient first increases slowly at 10 MPa and then grows significantly with increasing pressure. The impact of the pressure decreases at elevated temperature. The effect of permeability remains steady despite the temperature change during the experiments. The effect of gas state and porous media on the supercritical CO 2 diffusion coefficient was further discussed by comparing the results of this study with previous study. Based on the experimental results, an empirical correlation for supercritical CO 2 diffusion coefficient in n -decane-saturated porous media was developed. The experimental results contribute to the study of supercritical CO 2 diffusion in compact porous media.

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Oxidative Stress Biomarkers in Urine of Metal Carpentry Workers Can Be Diagnostic for Occupational Exposure to Low Level of Welding Fumes from Associated Metals

Cancers ◽

10.3390/cancers13133167 ◽

2021 ◽

Vol 13 (13) ◽

pp. 3167

Author(s):

Flavia Buonaurio ◽

Maria Luisa Astolfi ◽

Daniela Pigini ◽

Giovanna Tranfo ◽

Silvia Canepari ◽

...

Keyword(s):

Oxidative Stress ◽

Occupational Exposure ◽

Oxidation Products ◽

Control Group ◽

Welding Fumes ◽

Oxidative Stress Biomarkers ◽

Limit Values ◽

Stress Biomarkers ◽

Specificity And Sensitivity ◽

The Impact

Urinary concentrations of 16 different exposure biomarkers to metals were determined at the beginning and at the end of a working shift on a group of workers in the metal carpentry industry. Five different oxidative stress biomarkers were also measured, such as the oxidation products of RNA and DNA metabolized and excreted in the urine. The results of workers exposed to metals were compared to those of a control group. The metal concentrations found in these workers were well below the occupational exposure limit values and exceeded the mean concentrations of the same metals in the urine of the control group by a factor of four at maximum. Barium (Ba), mercury (Hg), lead (Pb) and strontium (Sr) were correlated with the RNA oxidative stress biomarker, 8-oxo-7, 8-dihydroguanosine (8-oxoGuo), which was found able to discriminate exposed workers from controls with a high level of specificity and sensitivity. The power of this early diagnostic technique was assessed by means of the ROC curve. Ba, rubidium (Rb), Sr, tellurium (Te), and vanadium (V) were correlated with the level of the protein oxidation biomarker 3-Nitrotyrosine (3-NO2Tyr), and Ba, beryllium (Be), copper (Cu), and Rb with 5-methylcytidine (5-MeCyt), an epigenetic marker of RNA damage. These effect biomarkers can help in identifying those workers that can be defined as “occupationally exposed” even at low exposure levels, and they can provide information about the impact that such doses have on their health.

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The impact of indium metal as a minor bimetal on the anodic dissolution and passivation performance of zinc for alkaline batteries: part I—potentiodynamic, potentiostatic, XRD, SEM, and EDAX studies

Journal of Solid State Electrochemistry ◽

10.1007/s10008-021-04998-8 ◽

2021 ◽

Author(s):

Abd El-Rahman Elsayed ◽

Hoda A. El-Shafy Shilkamy ◽

Mahmoud Elrouby

Keyword(s):

Anodic Dissolution ◽

Alkaline Batteries ◽

Indium Metal ◽

A Minor ◽

The Impact

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Teaching Faculty to Reach First-Generation College Students: The Impact of a Professional Development Course on Faculty

College Teaching ◽

10.1080/87567555.2021.1909526 ◽

2021 ◽

pp. 1-9

Author(s):

Rebecca Gutierrez Keeton ◽

Yoselinda Mendoza ◽

Maria Estela Zarate ◽

Emily Daniell Magruder

Keyword(s):

Professional Development ◽

College Students ◽

First Generation ◽

First Generation College Students ◽

First Generation College ◽

Teaching Faculty ◽

The Impact ◽

Development Course

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The Impact of Metabolic Scion–Rootstock Interactions in Different Grapevine Tissues and Phloem Exudates

Metabolites ◽

10.3390/metabo11060349 ◽

2021 ◽

Vol 11 (6) ◽

pp. 349

Author(s):

Sara Tedesco ◽

Alexander Erban ◽

Saurabh Gupta ◽

Joachim Kopka ◽

Pedro Fevereiro ◽

...

Keyword(s):

Agronomic Traits ◽

Phloem Exudate ◽

Graft Union ◽

Reciprocal Effect ◽

Metabolic Markers ◽

Interaction Studies ◽

Metabolic Interactions ◽

A Minor ◽

The Impact ◽

Related Compounds

In viticulture, grafting is used to propagate Phylloxera-susceptible European grapevines, thereby using resistant American rootstocks. Although scion–rootstock reciprocal signaling is essential for the formation of a proper vascular union and for coordinated growth, our knowledge of graft partner interactions is very limited. In order to elucidate the scale and the content of scion–rootstock metabolic interactions, we profiled the metabolome of eleven graft combination in leaves, stems, and phloem exudate from both above and below the graft union 5–6 months after grafting. We compared the metabolome of scions vs. rootstocks of homografts vs. heterografts and investigated the reciprocal effect of the rootstock on the scion metabolome. This approach revealed that (1) grafting has a minor impact on the metabolome of grafted grapevines when tissues and genotypes were compared, (2) heterografting affects rootstocks more than scions, (3) the presence of a heterologous grafting partner increases defense-related compounds in both scion and rootstocks in shorter and longer distances from the graft, and (4) leaves were revealed as the best tissue to search for grafting-related metabolic markers. These results will provide a valuable metabolomics resource for scion–rootstock interaction studies and will facilitate future efforts on the identification of metabolic markers for important agronomic traits in grafted grapevines.

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