Influence of inlet flow rate,pH, and beads mill operating condition on separation performance of sub-micron particles by electrical hydrocyclone

Experimental studies have been carried out about the separation performance of a special electrical hydrocyclone. In this study, effect of inlet flow rate, applied electrostatic potential, pH, and beads mill operating condition on separation performance of a special electrical hydrocyclone were investigated. A 0.5 wt% suspension of sub-micron silica dispersed by the beads mill was used as the test powder. A 20 mm electrical hydrocyclone in diameter with 20% of underflow was examined. A negative center electrode was vertically inserted inside the conical section and the potential difference up to 100 V was applied between the conical wall and the center electrode in the hydrocyclone.By use of beads mill, it was found that the negative values of zeta potential increases with the increase of the particles diameter. It was found that the separation performance of the electrical hydrocyclone increases significantly with the decrease of inlet flow rate and increase of the electrostatic potential, while the separation performance shows a less significant increase as the pH of suspension increases. Under several times of milling by use of the same beads, the values of zeta potential were not constant. The negative zeta potential of suspension attains the highest value under six times of milling by use of the same beads.A new model, based on the diffusive mass transfer equation in the conical section of the electrical hydrocyclone has been developed, and compared to the experimental results. It is found that the calculated results by the new model shows a qualitative agreement with the experimental results.     

Effect of gas introduction position on substrate etching by means of Ar-dominated graphite-cathodic-arc plasma beam in μT-FAD

Substrate etching by means of Ar-mixed graphite-cathodic-arc plasma beam was investigated in a newly-developed compact-type μT-FAD. The surface level and roughness change were measured as a function of the Ar gas flow rate, when Ar gas was introduced into the arc generation zone and in the vicinity of the substrate. When Ar gas was introduced to the arc generation zone, the etching rate was lower but the surface was relatively not roughened. When Ar gas was introduced in the vicinity of the substrate, the etching rate was higher but the surface was roughened. At the same gas flow rate (and pressure), the substrate was etched more than three times faster when Ar gas was introduced into the arc generation zone than to the vicinity of the substrate. After measuring the discharge and plasma conditions, the results were considered to be caused by the difference in the amount of plasma transported to the substrate.     

Sum-frequency-generation system for differential absorption lidar measurement of atmospheric nitrogen dioxide

A sum-frequency-generation system for differential absorption lidar measurement of atmospheric nitrogen dioxide in the lower troposphere was developed. The system uses a combination of a pair of KD*P crystals and a tunable dye laser with LDS 765 dye pumped by the second harmonic of a Nd:YAG laser to generate lambdaon and lambdaoff alternatively. Compared with the conventional system that uses Coumarin 445 dye pumped by the third harmonic, the output energy and long-term stability were improved. By use of this system, atmospheric NO2 concentrations of approximately 10-50 ppb were measured, with an instrumental error of approximately 7 ppb.     

Effects of long-chain fatty acids on cytosolic triacylglycerol accumulation and lipid droplet formation in primary cultured bovine mammary epithelial cells

Mammary epithelial cells have recently been shown to express and secrete leptin into milk and to accumulate triacylglycerol (TAG) in cytosol. We examined the effects on the accumulation of cytosolic TAG of free fatty acid addition to the medium bathing bovine mammary epithelial cells (bMEC). Both saturated (palmitic and stearic) and unsaturated (oleic and linoleic) fatty acids stimulated the accumulation of TAG in a concentration-dependent manner from 50 to 400 microM and the expression of mRNA expression for CD36, which is involved in the uptake and secretion of long-chain fatty acids. However, leptin mRNA expression and lipid droplet formation were significantly increased only by the addition of unsaturated, but not saturated, fatty acids. Interestingly, both types of fatty acids stimulated alphas1-casein mRNA expression. These data suggest that the expression of leptin is related to droplet formation, whereas CD36 is related to cytosolic TAG accumulation, and that fatty acids or cytosolic TAG accumulation also have a role to accelerate differentiation of bMEC as shown by casein synthesis.     

Effect of Al/Fe Ratio in Belite on the Microtexture Induced by the Remelting Reaction

During the remelting reaction, belite crystals with Al/Fe ratio <1 produced a liquid which formed droplets on the lamellar boundaries; the rate of remelting reaction was very low. Belite crystals with Al/Fe >1 produced a liquid which readily spread on the lamellae with a resulting high rate of reaction. At 1450°C the distribution coefficient of Al and Fe atoms between the belite and the interstitial liquid ((Al/Fe)^Belite/(Al/Fe)^Liquid) was about 0.8.     

Control of oxidation on NiSix during etching and ashing processes

The oxidation on nickel silicide (NiSi_x) during plasma etching and oxygen ashing is investigated for stable contact resistance on NiSi_x. NiSi_x exposed by various processes is observed by X-ray photoelectron spectroscopy. The oxidation on NiSi_x is promoted by the fluorine that remains during etching and the oxide thickness on n⁺ NiSi_x is greater than that on p⁺ NiSi_x. The remaining fluorine after etching can be decreased by in-situ nitrogen plasma treatment during the post-etching process. Therefore, the oxidation progress with exposure to air and the difference in oxidation on NiSi_x between n⁺ and p⁺ can be suppressed.     

Physical Properties,Crystallization, and Thermal/Hydrolytic Degradation of Poly(L‐lactide)/Nano/Micro‐Diamond Composites

The effects of incorporated nano/micro‐diamond (NMD) on the physical properties, crystallization, thermal/hydrolytic degradation of poly(L ‐lactic acid) (PLLA) were investigated for a wide NMD concentration range of 0–10 wt.‐%. Incorporated NMD increased the tensile modulus and strength of PLLA films but decreased the elongation at break of PLLA films. Incorporated NMD accelerated the crystallization of PLLA during heating and cooling and increased the absolute crystallization enthalpy of PLLA films (except for an NMD concentration of 10 wt.‐% during cooling) but did not alter the crystallization mechanism. Incorporated NMD increased and decreased the thermal stability of PLLA films for NMD concentrations of 1–5 and 10 wt.‐%, respectively, and increased the hydrolytic degradation resistance of PLLA films.

     

Use of a Semihollow‐Shaped Triethynylphosphane Ligand for Efficient Formation of Six‐ and Seven‐Membered Ring Ethers through Gold(I)‐Catalyzed Cyclization of Hydroxy‐Tethered Propargylic Esters

The formation of six‐ and seven‐membered ring ethers from hydroxy‐tethered propargylic esters was efficiently catalyzed by a cationic gold(I) complex with a semihollow‐shaped triethynylphosphane ligand. This gold catalysis showed a tolerance toward the reactions of primary, secondary, and tertiary alcohol substrates with various substitution patterns. A sterically congested 2,2,6,6‐tetraalkyl‐substituted tetrahydropyran derivative as well as 6,6‐ and 7,6‐fused bicyclic diethers were obtained in useful yields. In addition, the gold catalysis was applicable to the reaction of a sulfonamide‐tethered propargylic ester to give a piperidine derivative.     

Who may not benefit from continuous renal replacement therapy in acute kidney injury?

This study aimed to identify factors that may predict early kidney recovery (less than 48 hours) or early death (within 48 hours) after initiating continuous renal replacement therapy (CRRT) in acute kidney injury (AKI) patients. This is a multicenter retrospective observational study of 14 Japanese Intensive care units (ICUs) in 12 tertiary hospitals. Consecutive adult patients with severe AKI requiring CRRT admitted to the participating ICUs in 2010 (n = 343) were included. Patient characteristics, variables at CRRT initiation, settings, and outcomes were collected. Patients were grouped into early kidney recovery group (CRRT discontinuation within 48 hours after initiation, n = 52), early death group (death within 48 hours after CRRT initiation, n = 52), and the rest as the control group (n = 239). The mean duration of CRRT in the early kidney recovery group and early death group was 1.3 and 0.9 days, respectively. In multivariable regression analysis, in comparison with the control group, urine output (mL/h) (odds ratio [OR]: 1.02, 95% confidence interval [CI]: 1.01–1.03), duration between ICU admission to CRRT initiation (days) (OR: 0.65, 95% CI: 0.43–0.87), and the sepsis‐related organ failure assessment score (OR: 0.87, 95% CI; 0.78–0.96) were related to early kidney recovery. Serum lactate (mmol/L) (OR: 1.19, 95% CI: 1.11–1.28), albumin (g/dL) (OR: 0.52, 95% CI: 0.28–0.92), vasopressor use (OR: 3.68, 95% CI: 1.37–12.16), and neurological disease (OR: 9.64, 96% CI: 1.22–92.95) were related to early death. Identifying AKI patients who do not benefit from CRRT and differentiating such patients from the study cohort may allow previous and future studies to effectively evaluate the indication and role of CRRT.     

Highly Enhanced Nucleating Effect of Melt‐Recrystallized Stereocomplex Crystallites on Poly(L‐lactic acid) Crystallization

In the general processing temperature range of poly(L ‐lactic acid) (PLLA) articles (210–240 °C), PLLA/poly(D ‐lactic acid) (PDLA) stereocomplex (SC) crystallites melted just above the endset temperature of SC melting (228–238 °C) and recrystallized during cooling were found to act as the most effective nucleating agents for enhancing the crystallization of PLLA compared to partially melted SC crystallites (211–227 °C) or those melted far above the endset temperature of SC melting (240 and 250 °C) and recrystallized during cooling. The high nucleating effect of the SC crystallites melted in the temperature range of 228–238 °C was found to be caused by their smaller sizes or the larger number of SC crystallites per unit mass. The incorporation of such SC crystallites facilitates the processing of PLLA articles having high crystallinity and, therefore, high heat‐resistance in a shorter period to reduce the production cost.