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The purpose of this paper is to study the adsorption properties of a proven traditional medicine of West Africa origin, Alstonia boonei with an attempt to evaluate its application in the corrosion protection of mild steel in 5 M H₂SO₄ and 5 M HCl.

Phytochemical screening and Fourier transform infrared spectroscopy analysis were used to characterize the methanolic extract of the plant. Gravimetry, gasometry and electrochemical techniques were used in the corrosion inhibition studies of the extract and computational studies were used to describe the electronic and adsorption properties of eugenol, the most abundant phytochemical in Alstonia boonei.

The extract acted as a mixed-type inhibitor in both acidic solutions, with improved inhibition efficiency achieved with increasing concentration. While the efficiency increased with temperature for the HCl system, it decreased for the H₂SO₄ system. The mechanism of adsorption proposed for Alstonia boonei was chemisorption in the HCl system and physisorption in the H₂SO₄ system, and the adsorptions obeyed Langmuir isotherm at low temperatures. Computational parameters showed that eugenol, being a representative of Alstonia boonei, possesses excellent adsorption properties and has the potential to compete with other established plant-based corrosion inhibitors.

As opposed to pure compounds with distinctive corrosion effects, plant extracts are generally composed of a myriad of phytoconstituents that competitively promote or inhibit the corrosion process and their net effect is evident as inhibition efficiencies. This is, therefore, the main research limitation associated with the corrosion inhibition study of Alstonia boonei.

Being very rich in antioxidant properties by its proven curative and preventive effects for diseases, the interest was stimulated towards the attractive results that abound from its corrosion protection of metals via its anti-oxidation route.

Owing to the toxicity, biodegradability, and cost of most corrosion inhibitors, research attention is now focused on the development of environmentally benign, biodegradable, cheap, and efficient options. In consideration of these facts, chrysin, a phytocompound of Populus tomentosa (Chinese white poplar) has been isolated and investigated for its anticorrosion abilities on carbon steel in a mixed acid and chloride system. This highlights the main purpose of the study.

Chrysin was isolated from Populus tomentosa using column chromatography and characterized using Fourier Transform Infrared Spectroscopy and Nuclear Magnetic Resonance Spectroscopy. The investigations are outlined based on theory (Fukui indices, condensed density functional theory and molecular dynamic simulation) and experiments (electrochemical, gravimetry and surface morphology examinations).

Theoretical evaluations permitted the description of the adsorption characteristics, and molecular interactions and orientations of chrysin on Fe substrate. The interaction energy for protonated and neutral chrysin on Fe (110) were −149.10 kcal/mol and −143.28 kcal/mol, respectively. Moreover, experimental investigations showed that chrysin is a potent mixed-type corrosion inhibitor for steel, whose effectiveness depends on its surrounding temperature and concentration. The optimum inhibition efficiency of 78.7% after 24 h for 1 g/L chrysin at 298 K indicates that the performance of chrysin, as a pure compound, compares favorably with other phytocompounds and plant extracts investigated under similar conditions. However, the inhibition efficiency decreased to 62.5% and 51.8% at 318 K after 48 h and 72 h, respectively.

The novelty of this study relies on the usage of a pure compound in corrosion suppression investigation, thus eliminating the unknown influences obtainable by the presence of multi-phytocompounds in plant extracts, thereby advancing the commercialization of bio-based corrosion inhibitors.

Summary of Content Mein Kampf, Adolf Hitler (1925–1926), is in two parts, “Eine Abrechung” (A Reckoning) and “Die National‐Sozialistische Bewegung” (The National Socialist Movement). Written at different times, they originally appeared separately.

Nobody concerned with political economy can neglect the history of economic doctrines. Structural changes in the economy and society influence economic thinking and, conversely, innovative thought structures and attitudes have almost always forced economic institutions and modes of behaviour to adjust. We learn from the history of economic doctrines how a particular theory emerged and whether, and in which environment, it could take root. We can see how a school evolves out of a common methodological perception and similar techniques of analysis, and how it has to establish itself. The interaction between unresolved problems on the one hand, and the search for better solutions or explanations on the other, leads to a change in paradigma and to the formation of new lines of reasoning. As long as the real world is subject to progress and change scientific search for explanation must out of necessity continue.

Communications regarding this column should be addressed to Mrs. Cheney, Peabody Library School, Nashville, Term. 37203. Mrs. Cheney does not sell the books listed here. They are available through normal trade sources. Mrs. Cheney, being a member of the editorial board of Pierian Press, will not review Pierian Press reference books in this column. Descriptions of Pierian Press reference books will be included elsewhere in this publication.

This paper aims to look at the exchange context of peer-to-peer (P2P) collaborative consumption (e.g. Uber and Airbnb). Specifically, the paper examines the effect that the sharing of a personal possession, such as a car or apartment, may have on the consumer.

Two studies were conducted via online surveys. The surveys used vignettes that asked participants to imagine service experiences in either a P2P or a business-to-consumer (B2C) context. The participants then answered questions, including their perceptions of social closeness to the service provider, as well as willingness to pay (Study 1) and expectations of satisfaction (Study 2). The analysis used bootstrapping regression models to examine the relationships.

In both studies, the participants in the P2P conditions reported significantly greater perceived social closeness to the service provider than did those in the B2C condition. The P2P condition also resulted in significant indirect effects (i.e. mediated by social closeness) on willingness to pay (Study 1) and expectations of satisfaction (Study 2).

This paper extends the work on social distance to show that the effects are activated by the P2P exchange context. Also demonstrated here is that social closeness acts as an important mediator in the P2P context, affecting outcomes in the consumption and pre-consumption stages. Finally, construal level effects are extended to show that trend interpretation can be influenced by social distance.

Within the past few years, responsible educators, librarians, parents, counselors, social workers, therapists, and religious groups of all sexual persuasions and lifestyles have recognized the need for readily available reading material for lesbian and gay youth. Unfortunately, this material is often buried, because it is embedded in larger works. To meet this need, I have compiled and annotated 100 of the best works for young homosexuals, bisexuals, and heterosexuals. I have also included a few of the best works currently available on heterosexuality as a much needed source of knowledge for all young adults whether they are gay or straight, whether they remain childless or eventually become parents.

A history of twentieth‐century censorship. Shakespeare's company staged the first production of The Merchant of Venice sometime between 30 July 1596 and 22 July 1598. From the day of that presentation, it is probable that the play has annoyed, perhaps even offended, many who have seen or read it, the source of the offense being the disparaging portrait of a major character, Shylock. On the stage for many years, there have been radically discrepant interpretations of the Jewish usurer. Since the day of Sir Henry Irving, actors and directors have often chosen to present Shylock in a way that transforms the role from that which Elizabethan playgoers may have seen and heard, or may have thought they had seen and heard, to the complex, ambivalent personality depicted in all productions since Irving first projected Shylock as a tragic hero.

THE new library building has been open for six months now. It is pleasantly situated in an area of new buildings, and occupies a prominent island site just on the edge of the shopping centre. The old library was in the middle of a shopping area, and it has been interesting to note that our removal from that site has had a more considerable effect on the traffic pattern than one would have thought.

In all probability, there are today only four persons — all social scientists — who have personally known Father Heinrich Pesch, the eminent German economist of the Jesuit Order, viz., Oswald von Nell‐Breuning, SJ, who, 93 years old, still is amazingly active as lecturer and writer, the Rev. Dr. mult. L. H. Adolf Geck (1898), retired, yet still engaged in social research, Rev. Joh. Messner (1891), Professor Emeritus of the University of Vienna, whom illness has recently incapacitated, and the author of this article (1900), who thinks himself fortunate to have gained — during his years of study at the University of Berlin — Pesch's paternal friendship.