A Study on the Causal Relationship between Spot Price and Futures Price of Crude Oil and Agricultural Products

This paper studies the relationship between the agricultural, energy, and derivatives markets. This study empirically analyzes how the results of previous studies on the Granger causality between oil price and the spot price of agricultural products appear in the futures market by using the Toda and Yamamoto (1995)’ causality test. There are two main findings. First, 7 bidirectional causalities and 27 causalities between oil and 6 agricultural products are found, providing strong evidence of a causal relationship. Second, causality is found between oil prices and grain and oilseed type agricultural products, and the spot price of oil has relatively more causalities on agricultural product prices than the futures price of oil. Lastly, testing each period shows that a financial crisis can strengthen the relationship between the agriculture markets and the energy market

Recent Developments in Synthesis and Photocatalytic Applications of Carbon Dots

The tunable photoluminescent and photocatalytic properties of carbon dots (CDs) via chemical surface modification have drawn increased attention to this emerging class of carbon nanomaterials. Herein, we summarize the advances in CD synthesis and modification, with a focus on surface functionalization, element doping, passivation, and nanocomposite formation with metal oxides, transition metal chalcogenides, or graphitic carbon nitrides. The effects of CD size and functionalization on photocatalytic properties are discussed, along with the photocatalytic applications of CDs in energy conversion, water splitting, hydrogen evolution, water treatment, and chemical degradation. In particular, the enzyme-mimetic and photodynamic applications of CDs for bio-related uses are thoroughly reviewed

Control of size and physical properties of graphene oxide by changing the oxidation temperature

The size and the physical properties of graphene oxide sheets were controlled by changing the oxidation temperature of graphite. Graphite oxide (GO) samples were prepared at different oxidation temperatures of 20 degrees C, 27 degrees C and 35 degrees C using a modified Hummers' method. The carbon-to-oxygen (C/O) ratio and the average size of the GO sheets varied according to the oxidation temperature: 1.26 and 12.4 mu m at 20 degrees C, 1.24 and 10.5 mu m at 27 degrees C, and 1.18 and 8.5 mu m at 35 degrees C. This indicates that the C/O ratio and the average size of the graphene oxide sheets respectively increase as the oxidation temperature decreases. Moreover, it was observed that the surface charge and optical properties of the graphene oxide sheets could be tuned by changing the temperature. This study demonstrates the tunability of the physical properties of graphene oxide sheets and shows that the properties depend on the functional groups generated during the oxidation process.clos

First Confirmed Report of Powdery Mildew Caused by Erysiphe aquilegiae on Casuarina cunninghamiana in Argentina

Casuarina cunninghamiana Miq. (Fam. Casuarinaceae) is native to Australia and was introduced to Argentina and used as a windbreak, shade tree and for ornamental purposes. In autumn 2009, the potted seedlings in the nursery of La Plata University were found to be infected with a powdery mildew. Symptoms first appeared as thin white colonies, which subsequently developed into an abundant growth on the leaves and young stems. The damage caused by the powdery mildew infection has been observed every year after this initial infection and was again confirmed in April, 2011. There have been a few reports on the presence of powdery mildew on Casuarina spp. (Mantz et al., 2008; Farr and Rossman, 2011). In all the reports, the pathogen was cited to be Oidium sp. Thus, the aim of this work was to identify the causal agent of the powdery mildew observed on casuarina in Argentina

Scutellinia (Pezizales) In Korea, With A New Species and Eight New Records

Eleven species of the genus Scutellinia (Pyronemataceae, Pezizales) are recognized in Korea by analysis of macro- and micro-morphological characteristics, substrates and geographical distributions. Eight species are recorded new to Korea, namely, S. ahmadiopsis, S. badio-berbis, S. colensoi, S. jilinensis, S. nigrohirtula, S. olivascens, S. setosa and S. patagonica. Based on the exceptional length of marginal hairs and tuberculate ascospore wall ornamentation, two Korean specimens occurring on wood are described as a new species. Infraspecific morphological variations among collections within S. scutellata and S. patagonica were found. These are tentative treat as species complexes. The highly questionable occurrence of S. setosa in Asia was confirmed. Descriptions and taxonomic notes of the recognized species of Scutellinia are provided with a taxonomic key, illustrations and photographs of these species from Korea.Organismic and Evolutionary Biolog

Recent Progress in Plasmonic Hybrid Photocatalysis for CO2 Photoreduction and C-C Coupling Reactions

Plasmonic hybrid nanostructures have been investigated as attractive heterogeneous photocatalysts that can utilize sunlight to produce valuable chemicals. In particular, the efficient photoconversion of CO2 into a stable hydrocarbon with sunlight can be a promising strategy to achieve a sustainable human life on Earth. The next step for hydrocarbons once obtained from CO2 is the carbon-carbon coupling reactions to produce a valuable chemical for energy storage or fine chemicals. For these purposes, plasmonic nanomaterials have been widely investigated as a visible-light-induced photocatalyst to achieve increased efficiency of photochemical reactions with sunlight. In this review, we discuss recent achievements involving plasmonic hybrid photocatalysts that have been investigated for CO and CO2 photoreductions to form multi-carbon products and for C-C coupling reactions, such as the Suzuki-Miyaura coupling reactions