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81.
Hidenobu Mizuki Yudai Ito Saba Samatya Hisashi Harada Hidetaka Kawakita 《溶剂提取与离子交换》2013,31(1):146-156
Abstract A novel adsorbent Zr(IV)-immobilized resin was prepared to remove fluoride ions from tap water and industrial wastewater. In order to enhance both the kinetics and efficiency, large pathways were formed in the resin for fluoride ion adsorption and the Zr(IV)-phosphate complexes were immobilized on the polymer surface by surface-template polymerization. The Zr(IV)-immobilized resin had a fluoride adsorption capacity of 0.30 mmol/g. The morphology of the Zr(IV)-immobilized resin was evaluated by measuring the specific surface area, pore volume, and pore size distribution. The resin possessed large amounts of large macropores with diameters around 300 nm. The molecular structure at the fluoride adsorption sites was investigated by measuring the amounts of phosphorus, zirconium, and fluoride ion in the resin, and developing a model complex using computational chemistry. On the polymer surface, a fluoride ion/Zr(IV)/dioleyl phosphoric acid complex with an ideal F:Zr:P mole ratio of 3:1:3 could be formed. 相似文献
82.
83.
DLC films were deposited by a new pulsed DC discharge plasma chemical vapour deposition (CVD) using hydrogen and methane gas mixture. When methane concentration (Cm) i.e. CH4/(H2 + CH4) was increased from 3 to 40%, the graphitization of the carbon film increases as evident from Raman study. When Cm was increased to 30%, DLC film shows photoconducting property. The white light photoconductivity (S = Il/Id, where Il is light current and Id is dark current) measured with solar simulator under AM 1.5 condition was approximately 20 at room temperature. The photoconductivity was not clear when Cm was lower than 20%. ESR measurements also show that the electron spin density was slightly decreased with decreasing concentration of methane. Thus we can conclude here that at higher concentrations of methane at 30%, Sp2 content of the film increases and the DLC film becomes photoconducting. 相似文献
84.
A formalization of graphical processes in computer graphics systems is presented in terms of functions and their system of axioms. The concept of the viewing pipeline is formalized as operation sequence which is a sequential composition of graphical elementary operations. The formalization includes two kinds of operation sequences which are used as the formal specifications of graphics systems and display devices. In order to generate a graphics system using a display device, we introduced the concept of functionality-preserving transformation of operation sequences in terms of various types of commutations among primitive operations. A type of transformation, which is called extraction, plays a central role in the generation algorithm. 相似文献
85.
Reinforcement learning (RL) attracts much attention as a technique for realizing computational intelligence such as adaptive
and autonomous decentralized systems. In general, however, it is not easy to put RL to practical use. This difficulty includes
the problem of designing a suitable action space for an agent, i.e., satisfying two requirements in trade-off: (i) to keep
the characteristics (or structure) of an original search space as much as possible in order to seek strategies that lie close
to the optimal, and (ii) to reduce the search space as much as possible in order to expedite the learning process. In order
to design a suitable action space adaptively, in this article, we propose a RL model with switching controllers based on Q-learning
and an actor-critic to mimic the process of an infant’s motor development in which gross motor skills develop before fine
motor skills. Then a method for switching controllers is constructed by introducing and referring to the “entropy.” Further,
through computational experiments by using a path-planning problem with continuous action space, the validity and potential
of the proposed method have been confirmed. 相似文献
86.
Simultaneous single-frequency oscillations on different transitions have been observed experimentally in a laser-diode-pumped microchip LiNdP4O12 laser. The peculiar modal input-output characteristics and the antiphase relaxation oscillation dynamics have been reproduced theoretically using rate equations, including the strong spatial localization of population inversions, cross saturation, and resonant reabsorption loss in an unpumped region brought about by the inherent high Nd concentrations 相似文献
87.
Hasegawa Tatsuro Yamauchi Hisashi Sashida Yoshio Matsumoto Mitsuo 《Industrial Electronics, IEEE Transactions on》1985,(3):253-260
Recent application of distributed control systems to large-and medium-scale industrial plants requires effective and high-speed communication among the control devices each other to ensure high-performance operation. 相似文献
88.
89.
We investigated the mobility and distribution of cadmium (Cd), nickel (Ni) and zinc (Zn) in four contaminated soil profiles
from Bangladesh. The sources of contamination of these profiles were tannery wastes, city sewage and the wastes of pharmaceutical
and paper mill factories at different locations in Bangladesh. The samples were collected from the A-, B- and C-horizons of
each profile: two sub-samples from the A-horizon at depths of 0–5 cm (A1) and >5 cm (A2), and one sample each from the B-
and C-horizons. Soil samples were analysed for total metal content by dissolution in aqua regia followed by sequential extraction
of the fractions based on their varying solubility. There were six operationally defined groups of extraction sequences: water
soluble (F1), exchangeable (F2), carbonate (F3), oxide (F4), organic (F5) and residual (F6). The total concentration of Cd,
Ni and Zn in the A-horizon (0–5 cm) ranged from 0.10 to 0.62, from 31 to 54 and from 85 to 838 mg kg−1, respectively. In the B- and C-horizons, the concentrations of these metals decreased many fold, particularly in the city
sewage profile where the decrease for Cd and Zn was approximately fourfold. The distribution of metals among the chemical
fractions depended on their total concentrations. In the A1-horizon, Cd had the highest mobility factor [MF = (F1+F2+F3)/(F1+F2+F3+F4+F5+F6) × 100]
at 41–43% and Ni had the lowest at 3–13%, while Zn, showed intermediate values at 8–25%. The MF decreased with depth in all
soil profiles. Among the fractions, the residual fraction contained the lowest levels of Cd but the highest levels of Ni and
Zn. This state affected their relative mobility and distribution in soil profiles. Of the soil profiles, the mobility of all
metals was higher in the city sewage soil than in any of the other three soils investigated, suggesting that the former may
create a health risk by contaminating agricultural products and ground water as it also contained higher amounts of Cd and
Zn. 相似文献