Partial removal of PCDD/Fs, coplanar PCBS, and PCBS from municipal solid waste incineration fly ash by a column flotation process

Municipal solid waste incineration (MSWI) fly ash has recently attracted much attention because of its large quantity and enrichment of high toxic combustion generating organohalogen contaminants such as polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs), coplanar polychlorinated biphenyls (coplanar PCBs), and polychlorinated biphenyls (PCBs). Since the organohalogen contaminants in MSWI fly ash are known to be enriched in the unburnt carbon (UC) fraction, the organohalogen contaminants can therefore be removed by the removal of UC. In this research, we used a modified column flotation technique to remove the organic contaminants from MSWI fly ash. UC was removed for 27.7% under the flotation condition without chemical flotation aids. The removal efficiencies of UC, PCDD/Fs, coplanar PCBs, and PCBs are further improved by adding flotation aids during the flotation process. UC was removed for 49.0% by adding a collector assistant with a HLB value of 13.5 and a concentration in the kerosene of 3% during the flotation process. In addition,the UC removal efficiencies are increased with the decrease of the diameter of the micropores in the gas spargers. By optimizing the flotation condition, 41.9% total PCDD/Fs, 40.8% coplanar PCBs, and 44.1% PCBs with 64.0% UC have been successfully removed from MSWI fly ash. The total toxic equivalent (TEQ) of the fly ash was decreased from 6.2 ng/g to 4.2 ng/g in the residue.     

Enzymatic Synthesis of Chiral Phenylalanine Derivatives by a Dynamic Kinetic Resolution of Corresponding Amide and Nitrile Substrates with a Multi‐Enzyme System

Mutant α‐amino‐ε‐caprolactam (ACL) racemase (L19V/L78T) from Achromobacter obae with improved substrate specificity toward phenylalaninamide was obtained by directed evolution. The mutant ACL racemase and thermostable mutant D ‐amino acid amidase (DaaA) from Ochrobactrum anthropi SV3 co‐expressed in Escherichia coli (pACLmut/pDBFB40) were utilized for synthesis of (R)‐phenylalanine and non‐natural (R)‐phenylalanine derivatives (4‐OH, 4‐F, 3‐F, and 2‐F‐Phe) by dynamic kinetic resolution (DKR). Recombinant E. coli with DaaA and mutant ACL racemase genes catalyzed the synthesis of (R)‐phenylalanine with 84% yield and 99% ee from (RS)‐phenylalaninamide (400 mM) in 22 h. (R)‐Tyrosine and 4‐fluoro‐(R)‐phenylalanine were also efficiently synthesized from the corresponding amide compounds. We also co‐expresed two genes encoding mutant ACL racemase and L ‐amino acid amidase from Brevundimonas diminuta in E. coli and performed the efficient production of various (S)‐phenylalanine derivatives. Moreover, 2‐aminophenylpropionitrile was converted to (R)‐phenylalanine by DKR using a combination of the non‐stereoselective nitrile hydratase from recombinamt E. coli and mutant ACL racemase and DaaA from E. coli encoding mutant ACL racemase and DaaA genes.     

Near-IR dye-sensitized solar cells using a new type of ruthenium complexes having 2,6-bis(quinolin-2-yl)pyridine derivatives

New ruthenium(II)-polypyridyl complexes 1a (X=H) and 1b (X=Cl) having 2,6-bis(4-carboxyquinolin-2-yl)pyridine derivatives were synthesized as a sensitizer for dye-sensitized solar cells (DSCs), and their photophysical and photochemical properties were characterized. Both of the complexes showed broad electronic absorption bands in the near-IR region, which were assigned to the metal-to-ligand charge transfer (MLCT) transitions. On the other hand, the photovoltaic performance of the DSCs sensitized with them were different from each other. The DSC sensitized with 1a exhibited higher IPCE value than that of the one sensitized with 1b. The substituent effects on the ligand on photovoltaic performance of the DSCs were examined.     

A Universal Molecular Stent Method to Toughen any Hydrogels Based on Double Network Concept

Double‐network hydrogels (DN gels), despite their high water content, are the strongest and toughest soft and wet materials available. However, in conventional DN gels, which show extraordinarily high mechanical performance comparable to that of industrial rubbers, the first network must be a strong polyelectrolyte and this requirement greatly hinders the widespread application of these gels. A general method involving the use of a “molecular stent” for the synthesis of tough DN gels using any hydrophilic polymer as the first network is reported. This is the first reported method for the synthesis of tough DN gels using various neutral or weak polyelectrolyte hydrogels as the first network. This method helps extend the DN gel concept to various functional polymers and may increase the number of applications of hydrogels in various fields.     

基于情感向量距离的青少年用语的情感分析

In this paper, we propose a method for estimating emotion in Wakamono Kotoba that were not registered in the system, by using Wakamono Kotoba example sentences as features. The proposed method applies Earth Mover's Distance (EMD) to vector of words. As a result of the evaluation experiment using 14 440 sentences, higher estimation accuracy is obtained by considering emotional distance between wordsan approach that had not been used in the conventional research than by using only word importance value.     

Improvement of neuronal cell adhesiveness on parylene with oxygen plasma treatment

We improved adhesiveness of a neuron-like cell, PC12, on a Parylene-C surface by O(2) plasma treatment which changes the surface from hydrophobic to hydrophilic. Neural cell adhesiveness on the plasma-treated Parylene-C was more than twenty times better compared to non-treated Parylene-C and it was close to that on a conventional polystyrene tissue-culture dish.     

Failure of pseudo-periodic surrogates

A surrogate test is a method for determining the properties of time-series data. Some methods have been proposed to generate surrogate data that can be used to determine whether a pseudo-periodic time series has deterministic properties beyond pseudo-periodicity. Luo’s method is one such method. In this article, Luo’s method and the problems associated with it are discussed. In this method, surrogate datasets are produced by adding the time-shifted data to the original data. Consequently, the pseudo-periodicity of the time series is presumably preserved, but the fine structure related to the deterministic properties is destroyed. Luo’s method gives correct results for many data. However, it generates incorrect results for certain time series, for example, the time series of the Rössler chaotic attractor and phase-shifted sinusoidal waves. To overcome this problem, we propose an alternative method based on the Poincaré section.     

Soft manipulator inspired by octopi: object grasping in all anatomical planes using a tendon-driven continuum arm

Artificial Life and Robotics - In this paper, we focus on the development of a soft continuum arm manipulator inspired by the morphology of octopi and their intelligent behavior. The proposed arm...     

Six-legged crawling soft robot: NOBIYAKA

Artificial Life and Robotics - In recent years, soft robotics composed of soft silicone rubber have attracted significant attention, as they can adapt to various unknown environments owing to their...