In January 2018, the Chinese government implemented a ban on importation of foreign waste, including waste plastics and other miscellaneous waste. Consequently, this ban has changed the global ...plastic recycling options. The aim of this study is to clarify the environmental impact of the ban between China and Japan, which is the largest exporter of plastic waste. The question of whether these policies are fundamentally helping to reduce the environmental burden has also been discussed from the viewpoints of China and Japan. Plastics have been classified into seven categories. Material flow analysis (MFA) and CO2 emissions derived in the MFA were applied to examine the material flow of waste plastics and compare CO2 emissions of virgin and recycled resins in Japan and China before, and after, the ban. A scope for the MFA including the recycling process of waste plastics, virgin resin production, and shipping between countries was proposed, and the transition of the material flow and CO2 emissions caused by China's waste import ban were evaluated. Material flow relevant to both Japan and China was set as the scope. Material flow crossing the scope, such as import of waste plastic into China from countries other than Japan, and export of waste plastic from Japan to countries other than China before the ban was excluded. The main finding of MFA is that the transition in material flow between 2016 and 2018 in China demonstrated high virgin resin imports and exports in 2016, and 28% of recycled waste plastics in China were derived from imported waste plastic. After the ban, the amount of waste plastic imports decreased by more than 99%, causing domestic virgin resin production to increase. Other findings include that CO2 emissions of the input of virgin materials increased by up to 10%, and the CO2 emissions derived from virgin resin production increased by up to 11% in 2018 compared those reported in 2016. With this transition, the CO2 emissions of 1 kg of raw materials in 2018 increased by 0.24 kg compared with 2016. In contrast, Japan's exports decreased, and domestic recycled plastic input increased. The CO2 emissions of 1 kg of raw materials in 2018 decreased by 0.07 kg compared with 2016.
•Impact of China's waste plastic import ban was analyzed using MFA.•China increased virgin resin at the expense of reduced imports of waste plastics.•CO2 emissions from the production of 1 kg of virgin resin increased in China.•Japan's recycling increased at the expense of reduced exports of waste plastics.•CO2 emissions from the production of 1 kg of recycled resin increased in Japan.
Synthetic MR imaging enables the creation of various contrast-weighted images including double inversion recovery and phase-sensitive inversion recovery from a single MR imaging quantification scan. ...Here, we assessed whether synthetic MR imaging is suitable for detecting MS plaques.
Quantitative and conventional MR imaging data on 12 patients with MS were retrospectively analyzed. Synthetic T2-weighted, FLAIR, double inversion recovery, and phase-sensitive inversion recovery images were produced after quantification of T1 and T2 values and proton density. Double inversion recovery images were optimized for each patient by adjusting the TI. The number of visible plaques was determined by a radiologist for a set of these 4 types of synthetic MR images and a set of conventional T1-weighted inversion recovery, T2-weighted, and FLAIR images. Conventional 3D double inversion recovery and other available images were used as the criterion standard. The total acquisition time of synthetic MR imaging was 7 minutes 12 seconds and that of conventional MR imaging was 6 minutes 29 seconds The lesion-to-WM contrast and lesion-to-WM contrast-to-noise ratio were calculated and compared between synthetic and conventional double inversion recovery images.
The total plaques detected by synthetic and conventional MR images were 157 and 139, respectively (
= .014). The lesion-to-WM contrast and contrast-to-noise ratio on synthetic double inversion recovery images were superior to those on conventional double inversion recovery images (
= .001 and < 0.001, respectively).
Synthetic MR imaging enabled detection of more MS plaques than conventional MR imaging in a comparable acquisition time. The contrast for MS plaques on synthetic double inversion recovery images was better than on conventional double inversion recovery images.
To prepare high dielectric thin films of polymer-based materials, nanometre sized BaTiO3 particles, which should have high dielectric coefficients and low energy dissipation factors due to nano-size ...effects, were dispersed in polyvinylidene fluoride (PVDF) or siloxane-modified polyamideimide (SPAI). BaTiO3 particles with crystal sizes of 10.5-34.6 nm were synthesised with a complex alkoxide method. Polymer/N-methyl-2-pyrrodinone solution suspending the BaTiO3 particles was spin-coated on ITO glass substrates to prepare polymer-based composite films with submicron thickness. The BaTiO3 particles were dispersed more homogeneously in the PVDF film than in the SPAI film. The good dispersion of the particles in the PVDF film brought about a smooth film surface that had a root mean square roughness < 20 nm at a particle volume fraction of 30%. The roughness was less than one-tenth of the roughness of the SPAI composite film. An increase in the BaTiO3 crystal size from 10.5 to 34.6 nm in the PVDF film at a particle volume fraction of 30% increased the dielectric constant of the film from 20.1 to 31.8. The BaTiO3-PVDF composite film attained a high dielectric constant with more than twice the dielectric constant of the BaTiO3-SPAI composite film. The dissipation factor of the PVDF composite film was as low as 0.05 at 10000 Hz. 16 refs.
•Sequential extraction was carried out in three steps using scCO2, ethanol and water.•High extraction yield and extracts with more than 20% of phenolic compounds and high antioxidant activity were ...obtained.•The antioxidant activity by DPPH assay measured as EC50 could be correlated to the total phenolics content.•The major compound of volatile supercritical extract was thymol with 78% of relative area.
Extraction of bioactive compounds requires frequent changes in the extraction techniques due to the quality requirements in the food, pharmaceutical and cosmetic industries. The compounds of the polyphenolic family represent an important group of bioactive compounds in food, and are present in various types of plants, including Lippia sidoides Cham., also known as pepper-rosmarin, an aromatic plant with therapeutic properties. Thus, this study aimed to investigate the sequential extraction (in fixed bed and high pressure) of bioactive compounds from L. sidoides leaves, using supercritical carbon dioxide, ethanol, and water as solvents and, compare the global yield, total phenolics, total flavonoids, and antioxidant activity of extracts obtained from sequential extraction with the extracts obtained by one-step extraction in fixed bed (high pressure) and by conventional extraction. The results showed that the combination of extraction processes is an effective method to obtain extracts with different compositions and functionalities. Overall, the ethanolic extraction in fixed bed and the three-step sequential extraction showed the best results in terms of global yield, and content and yield of total phenolics and flavonoids. The ethanol extracts exhibited the best antioxidant activity, which may be related to the presence of phenolic compounds.
For the finishing of difficult-to-machine materials, plasma-assisted polishing (PAP), which combines modification by water vapor plasma and polishing by a soft abrasive, was proposed. Optimization of ...plasma oxidation and abrasive polishing was conducted to increase the material removal rate of PAP, which was applied to 4H-SiC (0001). It was found that with a low concentration of water vapor in helium gas, the plasma oxidation rate was greatly increased. Also, because of the different oxidation rates of the four types of terrace that appear alternately in 4H-SiC, a high removal rate of the oxide was necessary to obtain a uniform step–terrace structure with atomic order.
•Sequential extraction was carried out in three steps using scCO2, ethanol and water.•One high global extraction yield of 43% was obtained in the sequential extraction.•The effect of the prior ...supercritical extraction allowed to obtain ethanolic extracts more concentrated in phenolic compounds.•The antioxidant activity by DPPH assay measured as EC50 could be correlated to the total phenolics content.•The main compounds of supercritical volatile fraction were germacrene, caryophyllene and derivated from selina.
With the goal of maximizing the extraction yield of phenolic compounds from pitanga leaves (Eugenia uniflora L.), a sequential extraction in fixed bed was carried out in three steps at 60°C and 400bar, using supercritical CO2 (non-polar) as solvent in a first step, followed by ethanol (polarity: 5.2) and water (polarity: 9.0) in a second and third steps, respectively. All extracts were evaluated for global extraction yield, concentration and yield of both polyphenols and total flavonoids and antioxidant activity by DPPH method (in terms of EC50). The nature of the solvent significantly influenced the process, since the extraction yield increased with solvent polarity. The aqueous extracts presented higher global extraction yield (22%), followed by ethanolic (16%) and supercritical extracts (5%). The study pointed out that the sequential extraction process is the most effective in terms of global extraction yield and yield of polyphenols and total flavonoids, because it produced the more concentrated extracts on phenolic compounds, since the supercritical ethanolic extract presented the highest phenolics content (240.5mg GAE/g extract) and antioxidant capacity (EC50=9.15μg/mL). The most volatile fraction from the supercritical extract, which is similar to the essential oils obtained by steam distillation or hydrodistillation, presented as major compounds the germacrenos D and B+bicyclogermacrene (40.75%), selina-1,3,7(11)-trien-8-one+selina-1,3,7(11)-trien-8-one epoxide (27.7%) and trans-caryophyllene (14.18%).
Abstract
GRAPES-3 is a mid-altitude (2200 m) and near-equatorial (11.°4N) air shower array, overlapping in its field of view for cosmic-ray observations with experiments that are located in the ...Northern and Southern Hemispheres. We analyze a sample of 3.7 × 10
9
cosmic-ray events collected by the GRAPES-3 experiment between 2013 January 1 and 2016 December 31 with a median energy of ∼16 TeV for study of small-scale (<60°) angular-scale anisotropies. We observed two structures, labeled A and B, that deviate from the expected isotropic distribution of cosmic rays in a statistically significant manner. Structure A spans 50°–80° in R.A. and from −15° to 30° in decl. The relative excess observed in structure A is at the level of (6.5 ± 1.3) × 10
−4
with a statistical significance of 6.8 standard deviations. Structure B is observed in the R.A. range 110°–140° and at decl. from −10° to 30°. The relative excess observed in this region is at the level of (4.9 ± 1.4) × 10
−4
with a statistical significance of 4.7 standard deviations. These structures are consistent with those reported by Milagro, ARGO-YBJ, and HAWC. These observations could provide a better understanding of the sources of cosmic rays, their propagation, and the magnetic structures in our Galaxy.
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•Solubility of oleic acid in supercritical CO2 was measured.•The solubility of the sunflower oil blend with oleic acid in scCO2 was measured.•The critical properties values was ...crucial to well correlate the data from the phase equilibrium.•The modeling using Peng-Robinson equation was unable to represent the ternary system.
To evaluate the selectivity of supercritical carbon dioxide (scCO2) as a solvent to deacidify vegetable oils, the solubility of oleic acid and of a mixture of oleic acid and refined sunflower oil in scCO2 was measured. Sunflower oil was adopted as a pseudo-pure component and the phase equilibrium of ternary and binary systems were thermodynamically modeled by the Peng-Robinson equation of state with classical mixing rule. The values of the estimated and/or adopted critical properties in modeling thermodynamics were shown to be of great influence on the quality of data correlation. Although correlating data from binary systems is possible, the modeling was incapable of satisfactorily predicting the behavior of the phase equilibrium of the ternary system. The large deviations observed may derive from the presence of specific intermolecular interactions between the components of these systems that were not considered in this type of modeling.
Graphite oxide was silylated by various alkylchlorosilanes in the presence of butylamine and toluene, and new intercalation compounds were obtained. The silylating reagents with two or three chlorine ...atoms at silicon in them reacted with graphite oxide, while no reaction occurred when silylating reagents with only one chlorine atom was used. The silylating reagent mainly reacted with hydroxyl group of graphite oxide, forming Si–O bonding. The role of butylamine was not only exfoliating graphite oxide layer but also scavenging HCl molecule which caused the decomposition of silylated graphite oxide. The silicon content was almost constant ≈0.6
mol/graphite oxide for the samples silylated by alkyltrichlorosilane with shorter alkyl chain lengths. It increased with the increase of alkyl chain length and reached 1.7
mol/graphite oxide. The higher silicon content could be ascribed to further silylation on hydroxyl groups formed at silicon atoms of silylating reagent bonded to graphite oxide, bridging two silylating reagents.
A higher body mass index (BMI) is a predictor of better survival in hemodialysis patients, although the relative importance of body fat and lean mass has not been examined in the dialysis population. ...We performed an observational cohort study in 808 patients with end-stage renal disease on maintenance hemodialysis. At baseline, fat mass was measured by dual-energy X-ray absorptiometry and expressed as fat mass index (FMI; kg/m2). Lean mass index (LMI) was defined as BMI minus FMI. During the mean follow-up period of 53 months, 147 deaths, including 62 cardiovascular (CV) and 85 non-CV fatal events, were recorded. In univariate analysis, LMI was not significantly associated with CV or non-CV death, whereas a higher FMI was predictive of lower risk for non-CV death. Analyses with multivariate Cox models, which took other confounding variables as covariates, indicated the independent associations between a higher LMI and a lower risk of CV death, as well as between a higher FMI and a lower risk of non-CV death. These results indicate that increased fat mass and lean mass were both conditions associated with better outcomes in the dialysis population.
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