Kinetic study and thermal decomposition behavior of viscoelastic memory foam

A systematic investigation of the thermal decomposition of viscoelastic memory foam (VMF) was performed using thermogravimetric analysis (TGA) to obtain the kinetic parameters, and thermogravimetric analysis coupled to Fourier Transformed Infrared Spectrometry (TGA-FTIR) and thermogravimetric analysis coupled to Mass Spectrometry (TGA-MS) to obtain detailed information of evolved products on pyrolysis and oxidative degradations. Two consecutive nth-order reactions were employed to correlate the experimental data from dynamic and isothermal runs performed at three different heating rates (5, 10 and 20 K/min) under an inert atmosphere. On the other hand, for the kinetic study of the oxidative decomposition, the data from combustion (synthetic air) and poor oxygen combustion (N2:O2 = 9:1) runs, at three heating rates and under dynamic and isothermal conditions, were correlated simultaneously. A kinetic model consisting of three consecutive reactions presented a really good correlation in all runs. TGA-FTIR analysis showed that the main gases released during the pyrolysis of VMF were determined as ether and aliphatic hydrocarbons, whereas in combustion apart from the previous gases, aldehydes, amines and CO2 have also been detected as the main gases. These results were confirmed by the TGA-MS.

Rules and orders relating to a Professor of the Mathematicks, of Natural and Experimental Philosophy, in Harvard College, 18 January 1726

This folder contains a single document describing the "rules and orders" of the Hollis Professor of Mathematics and Natural Philosophy. The document begins by defining the subjects to be taught by the Hollis Professor including natural and experimental philosophy, elements of geometry, and the principles of astronomy and geography. It then outlines the number of public and private lectures to be given to students, how much extra time the professor should spend with students reviewing any difficulties they may encounter understanding class subject matter discussed, and stipulates that the professor's duties shall be restricted solely to his teaching activities and not involve him in any religious activities at the College or oblige him to teach any additional studies other than those specified for the Hollis Professor of Mathematics and Natural Philosophy. Furthermore, the rules establish the professor's salary at £80 per year and allow the professor to receive from students, except those students studying theology under the Hollis Professor of Divinity, an additional fee as determined by the Corporation and Board of Overseers, to supplement his income. Moreover, the rules assert that all professorship candidates selected by the Harvard Corporation must be approved by Thomas Hollis during his lifetime or by his executor after his death. Finally, the rules state that the Hollis professor take an oath to the civil government and declare himself a member of the Protestant reformed religion. This document is signed by Thomas Hollis and four witnesses, John Hollis, Joshua Hollis, Richard Solly, and John Williams.

John Winthrop's proposal respecting electrical globes and jars, ca. 1758

In this proposal, John Winthrop explains the need to replace damaged "electric globes" used in the College's collection of scientific apparatus. He states that Benjamin Franklin, at the time residing in London, was willing to seek replacement globes for the College's collection. Winthrop then proceeds to assert that the College should acquire "square bottles, of a moderate size, fitted in a wooden box, like what they call case bottles for spirits" instead of the large jars included in the scientific apparatus, because those jars cracked frequently.

Student mathematical textbook of James Freeman, 1774

Manuscript volume containing portions of text copied from Nicholas Saunderson’s Elements of algebra, Nicholas Hammond’s The elements of algebra, and John Ward’s The young mathematician’s guide. The volume is divided into two main parts: the first is titled Concerning the parts of Arithmetick (p. 1-98) and the second, The elements of Algebra, extracted from Hammond, Ward & Saunderson (p. 99-259).

A catechism geographical, historicall and chronologicall

Notebook of unlined pages holding a handwritten copy of Tutor Flynt's "Catechism" copied by Harvard student Hull Abbot (1702-1774, Harvard AB 1720). The volume lists questions and accompanying answers on various academic subjects.

A catechism geographicall, historical and chronologicall 1719

Notebook of unlined pages with paper marbled cover holding a handwritten copy of Tutor Flynt's "Catechism" likely copied by Harvard student John Wolcott in 1719. The volume lists questions and accompanying answers on various academic subjects. On the last page, the inscription "John Wolcott [the name is crossed over] his geography, 1719" indicates Wolcott (1702-1747), a member of the Harvard class of 1721, copied the book.

Clerk's Book, A.D. 1742

Handwritten volume containing the Articles, weekly orations, and clerk's journal for the Harvard Latin Society recorded by the club's clerk, Jonathan Mayhew (Harvard AB 1744). The Articles define the Society's mission as to "improve ourselves in the knowledge of the Latin Tongue." The ten articles are signed to by ten members of the classes of 1743 and 1744. The journal which records the weekly meetings from April 14, 1742 through June 17, 1742 includes a transcription of the weekly oration in Latin; the first two entries are also translated into English. On the last page of the book, the "clerk's journal" provides a summary of each meeting with the date, the moderator, and the orators.

Of the invention of theorems : manuscript, [17--]

Mathematical notes, equations, theorems, and definitions. Probablynot by William Winthrop (Harvard AB 1770) as it is different handwriting and language habits from other of his manuscript.

Treatise on mathematics and astronomy: written about the year 1680, in Boston

Bound volume containing a late 17th century handwritten mathematical and astronomical text in one hand. The text is separated into mathematical and astronomical sections with rules, instructions for performing calculations, tables, and drawings. The subjects include arithmetic, geometry, astronomy, and trigonometry, and segments have titles such as "Subtraction," "A decimal table of English coince," "Logarithes & their use," and "To find the true place of the sun." The text is undated and unattributed but references Briggs, Oughtred, Ramus, and Apollonius. Certain tables are calculated from latitudinal and longitudinal numbers associated with Boston, and many of the examples use dates in the 1670s and 1680. The manuscript pages are mounted onto unruled pages, and some of the manuscript pages are fragments.

Mathematical notebook, and commonplace book, circa 1689-1769

Manuscript notebook, possibly kept by Harvard students, containing 17th century English transcriptions of arithmetic and geometry texts, one of which is dated 1689-1690; 18th century transcriptions from John Ward’s “The Young Mathematician’s Guide”; and notes on physics lectures delivered by John Winthrop, the Hollis Professor of Mathematics and Natural Philosophy at Harvard from 1738 to 1779. The notebook also contains 18th century reading notes on Henry VIII, Tudor succession, and English history from Daniel Neal’s “The History of the Puritans” and David Hume’s “History of England,” and notes on Ancient history, taken mainly from Charles Rollin’s “The Ancient History of the Egyptians, Carthaginians, Assyrians, Babylonians, Medes and Persians, Macedonians and Grecians.” Additionally included are an excerpt from Plutarch’s “Lives” and transcriptions of three articles from “The Gentleman’s Magazine, and Historical Chronicle,” published in 1769: “A Critique on the Works of Ovid”; a book review of “A New Voyage to the West-Indies”; and “Genuine Anecdotes of Celebrated Writers, &.” The flyleaf contains the inscription “Semper boni aliquid operis facito ut diabolus te semper inveniat occupatum,” a variation on a quote of Saint Jerome that translates approximately as “Always good to do some work so that the devil may always find you occupied.” In the seventeenth and eighteenth centuries, Harvard College undergraduates often copied academic texts and lecture notes into personal notebooks in place of printed textbooks. Winthrop used Ward’s textbook in his class, while the books of Hume, Neal, and Rollin were used in history courses taught at Harvard in the 18th century.

Student lectures notes on chemistry and materia medica, and medical recipes, of Lyman Spalding, 1795-1799 (inclusive)

Contains notes taken by Harvard student Lyman Spalding during eleven chemistry lectures delivered by Harvard Professor Aaron Dexter (1750-1829) in the fall of 1795 and recipes prepared and used by Spalding in his medical practice in 1797. The recipes include elixir vitriol, containing liquor, Jamaica pepper, cinnamon, and ginger, and an electuary for a cough, containing oxymel squills (sea onion in honey), licorice, antimonium tartaricum potash (a compound of the chemical element antimony and a potassium-containing salt), and opium. The volume also contains writings about chemistry by Spalding, some of which appear transcribed from published sources, in undated entries, and a diary entry from 1799 regarding an experiment with water.