Cellulose-Based Films with Ultraviolet Shielding Performance Prepared Directly from Waste Corrugated Pulp

As the most important paper packaging materials, corrugated cartons with a tremendous amount of production demonstrate several advantages and have been widely used in daily life. However, waste corrugated cartons (WCCs) are usually recycled and reused to produce new corrugated cartons, and their properties are decreased dramatically after several cycles. Therefore, recycling and converting WCCs into cellulose-based film with high value is attractive and significant. Herein, without any pretreatment, the waste old corrugated cartons were directly dissolved in ionic liquid 1-allyl-3-methylimidazolium chloride, and semitransparent cellulose-based films were successfully fabricated. It was indicated that cellulose-based films displayed better UV-shielding property and hydrophobicity than traditional cellulose films. Interestingly, the cellulose-based films regenerated from deionized water displayed higher tensile strength, elongation at break, and toughness. Their tensile strength could reach 23.16 MPa, exhibiting enormous superiority as wrapping and packaging materials to replace the petrochemical polyethylene membrane (8.95 MPa). Consequently, these renewable, biodegradable, and high-valued cellulose-based films were successfully fabricated to simultaneously realize the valorization of old corrugated cartons and supplement the petrochemical plastics.

Development of paleontological art in Poland

ABSTRACT The first illustrations of geo-objects—different crystals of salt—from Poland were included by U. Aldrovandi in his Musaeum Metallicum (1648). The first publications containing paleontological sketches of fossil remains of animals and plants appeared in the early eighteenth century. G.A. Helwing, in his Lithographia Angerburgica (1717) and Lithographiae Angerburgicae Pars II (1720), included drawings of fossils of various ages from the Peri-Baltic area. G.A. Volkmann’s Silesia Subterranea (1720) was extensively illustrated by elaborate sketches of fossils including Carboniferous plants from the Lower Silesia region. In 1764, J.-É. Guettard published an important paper on the geology of Poland that contained detailed illustrations of fossils from various parts of the country. S. Staszic, in his two seminal books published in 1805 and 1815, provided detailed illustrations of animal remains, mainly bones of large, extinct mammals. This “pioneering era” of development of paleontological art came to an end with publications by two geologists that laid the foundations of modern paleontology in Poland: Polens Paläontologie by G.G. Pusch (1836) and Paleontologia Polska (1846) by L. Zejszner. In less than 150 years, paleontological art evolved from simple illustrations of “curious objects” from the subsurface to scientific drawings that marked the birth of modern paleontology.

Mapping variation of handsheet properties within loblolly pine trees

Within-tree variation of four handsheet properties (burst index, sheet density, STFI short-span compression strength (STFI) and tensile index) was mapped for loblolly pine trees aged 13 and 22 years using NIR predicted handsheet property data (representing an average of 18 trees for each age). All within-tree maps were similar demonstrating a radial decrease in handsheet properties at all heights, with sheet density and tensile index having the greatest within-tree variation. The corewood zone had the highest values for all properties, while the lowest values were observed in a region consistent with juvenile and transitional outerwood as defined by Burdon et al. (2004). The maps are also similar to, but the inverse of, maps reported in prior studies for density and tracheid coarseness and wall thickness. Relationships amongst the examined handsheet properties and wood and tracheid properties explains the overall similarities of the different maps. The maps provide a representation of within-tree variation of important paper properties at two different ages. An understanding of how these properties vary within loblolly pine trees can aid in better utilization of forest resources.

An Epistemic Troika

In a characteristically stimulating and important paper, ‘Episteme’, Myles Burnyeat discusses what he calls the epistemic troika, which consists of knowledge by acquaintance, knowledge that, and knowledge how. He argues that the troika ‘lacks universal validity’; he ‘suspects’ that it is the product of Anglophone philosophy in the 1950s-early 1970s. He also challenges the philosophical value of the troika. In my paper, I explore the troika, both in its own right and as a guide to Plato’s epistemology; I also assess Burnyeat’s views on these issues.

Revisiting the paper on “Applications of graph theory to enzyme kinetics and protein folding kinetics: steady and non-steady state systems”

About 30 years ago a very important paper on “Applications of graph theory to enzyme kinetics and protein folding kinetics: steady and non-steady state systems”

Liberal Utilitarianism—Yes, But for Whom?

In his important paper “Just Better Utilitarianism,” Matti Häyry reminds his readers that liberal utilitarianism can offer a basis for moral and political choices in bioethics and thus could be helpful in decisionmaking.1 Although I agree with the general defense of Häyry’s liberal utilitarianism, in this commentary, I urge Häyry to say more on who belongs to our moral community. I challenge Häyry’s principle of actual or prospective existence. I also argue that Häyry should say more on human beings at the “margin of life” (such as fetuses and other mindless humans). I claim that debate over whether some form of utilitarianism is superior over other moral theories is not as important as answering the question underlying these issues: Who belongs to our moral community?

Homological dimension of elementary amenable groups

In this paper we prove that the homological dimension of an elementary amenable group over an arbitrary commutative coefficient ring is either infinite or equal to the Hirsch length of the group. Established theory gives simple group theoretical criteria for finiteness of homological dimension and so we can infer complete information about this invariant for elementary amenable groups. Stammbach proved the special case of solvable groups over coefficient fields of characteristic zero in an important paper dating from 1970.