Electron spin phase relaxation of phosphorus donors in nuclear spin enriched silicon

We report a pulsed EPR study of the phase relaxation of electron spins bound to phosphorus donors in isotopically purified 29^Si and natural abundance Si single crystals measured at 8 K.Comment: 5 pages, 3 figure

Improving the efficiency of essential-oil extraction from Abies sachalinensis with an underwater shockwave pretreatment

Abies sachalinensis (Sakhalin fir) is a conifer species belonging to the family Pinaceae that is native to and widely distributed throughout Sakhalin Island, the southern Kurils (Russia), and northern Hokkaido (Japan). The essential oil of A. sachalinensis has been found to be an active removal agent, similar to γ-terpinene, myrcene, and β-phellandrene, which effectively remove nitrogen dioxide. Essential oils provide a relaxing effect; the use of essential oils is expected to improve overall air quality.                Underwater shockwaves generate instantaneous high pressure that reaches the entire cell and causes multiple cracks along the tracheids, causing the pit membrane to flake off through spalling destruction. These cracks function as permeation pathways [1]; this application was expected to result in a more effective essential oil extraction by subsequent steam distillation [2]. We, herein, introduce a novel application of this pretreatment process aimed at improving the efficiency of essential-oil extraction from A. sachalinensis leaves and branches. A. sachalinensis leaves and branches were oven-dried (40-45 °C) to a moisture content of 10% or less, and were subjected to the shockwave pretreatment or left untreated before essential-oil extraction by steam distillation. Chemical analysis was performed using gas chromatography-mass spectrometry. The essential-oil yields of raw untreated and untreated dried leaves were 5.1 and 2.4 g/kg of leaf dry weight (DW), respectively. Upon application of a 3.0 kV, 3.6 kJ shockwave, the essential-oil yield increased with the number of shockwave cycles; the yield was 32.7 g/kg DW after 10 cycles, a 13.6-fold increase compared to that of the untreated dried leaves. In addition, sesquiterpenes increased by more than 30-fold in content compared to that of untreated dried leaves. Thus, these results suggest that instantaneous high-pressure treatment, as a pretreatment for conventional steam distillation, has a distinct advantage in increasing the essential-oil yield and extracting the bioactive components. Furthermore, this method also can be used for the pretreatment of microwave essential-oil extraction or steam distillation under reduced pressure

Numerical Simulation of Turbulent Spray Combustion Flows by using LES

特集1 乱流シミュレーションと流れの設計(TSFD

Quassinoids in Brucea javanica are potent stimulators of lipolysis in adipocytes

Obesity is associated with a number of metabolic disorders. Lipolysis is the initial step in the metabolism of lipids stored in adipocytes and is therefore considered a therapeutic target for obesity. Quassinoids are unique terpenes found in plants of the Simaroubaceae family, which were recently reported to have lipolytic activity and to suppress weight gain. Brucea javanica is a plant employed in traditional medicines in Asia, which is known to contain various quassinoids. Here, we investigated the lipolytic activity of B. javanica extracts, and identified six quassinoids: brucein A, brucein B, brucein C, 3′-hydroxybrucein A, brusatol, and bruceantinol, which represent the bioactive principals. The quassinoids contained in B. javanica demonstrated lipolytic activity at nanomolar concentrations, which were an order of magnitude lower than those of the previously reported quassinoids, suggesting that they may be useful for the treatment of obesity