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11.
Conventional water reclamation processes, such as membrane bioreactors, are not always effective in removal of pharmaceuticals and personal care products (PPCPs), endocrine disrupting chemicals (EDCs) and/or N-nitrosodimethylamine (NDMA), even with the reverse osmosis (RO) membrane process. A study was conducted, at a NEWater factory in Singapore, to compare a conventional ultrafiltration (UF) membrane /RO treatment process with a treatment train having the HiPOx unit, an advanced oxidation process (AOP), which was installed between the UF and the RO unit operations. By incorporating the HiPOx into the UF/RO treatment process, following results were observed; 1) increased removal of PPCPs, EDCs and NDMA, 2) improvement in ultraviolet transmission (UVT) of the RO permeate, 3) enhanced removal of TOC and color, and increased UVT of the RO brine, 4) suppression of the increase in the RO transmembrane pressure by organic fouling. 相似文献
12.
Quantitative phase imaging(QPI)with its high-contrast images of optical phase delay(OPD)maps is often used for label-free single-cell analysis.Contrary to other imaging methods,sensitivity improvement has not been intensively explored because conventional QPI is sensitive enough to observe the surface roughness of a substrate that restricts the minimum measurable OPD.However,emerging QPI techniques that utilize,for example,differential image analysis of consecutive temporal frames,such as mid-infrared photothermal QPI,mitigate the minimum OPD limit by decoupling the static OPD contribution and allow measurement of much smaller OPDs.Here,we propose and demonstrate supersensitive QPI with an expanded dynamic range.It is enabled by adaptive dynamic range shift through a combination of wavefront shaping and dark-field QPI techniques.As a proof-of-concept demonstration,we show dynamic range expansion(sensitivity improvement)of QPI by a factor of 6.6 and its utility in improving the sensitivity of mid-infrared photothermal QPI.This technique can also be applied for wide-field scattering imaging of dynamically changing nanoscale objects inside and outside a biological cell without losing global cellular morphological image information. 相似文献
13.
Wesley P. Chan Hiroto Mizohana Xiangyu Chen Yasuto Shiigi Yoshiyuki Yamanoue Masaki Nagatsuka Masayuki Inaba 《野外机器人技术杂志》2019,36(1):17-33
The use of field robots can greatly decrease the amount of time, effort, and associated risk compared to if human workers were to carryout certain tasks such as disaster response. However, transportability and reliability remain two main issues for most current robot systems. To address the issue of transportability, we have developed a lightweight modularizable platform named AeroArm. To address the issue of reliability, we utilize a multimodal sensing approach, combining the use of multiple sensors and sensor types, and the use of different detection algorithms, as well as active continuous closed‐loop feedback to accurately estimate the state of the robot with respect to the environment. We used Challenge 2 of the 2017 Mohammed Bin Zayed International Robotics Competition as an example outdoor manipulation task, demonstrating the capabilities of our robot system and approach in achieving reliable performance in the fields, and ranked fifth place internationally in the competition. 相似文献
14.
Y Takeda I Miyamori T Yoneda K Furukawa S Inaba R Takeda H Mabuchi 《Canadian Metallurgical Quarterly》1997,30(4):953-956
The mechanism underlying the central hypertensinogenic effects of mineralocorticoids remains unclear. Given that nitric oxide (NO) is thought to act at autonomic sites in the brain to regulate arterial blood pressure, the effects of the potent mineralocorticoids aldosterone and 19-noraldosterone on the abundance of neuronal NO synthase (nNOS) mRNA in the brain were investigated. Wistar-Kyoto rats received a continuous intracerebroventricular infusion of aldosterone or 19-noraldosterone (5 ng/h) from an implanted osmotic minipump for 4 weeks. Total RNA was purified from microdissected tissue blocks containing the hypothalamus, dorsal medulla, rostral ventrolateral medulla, or caudal ventrolateral medulla, and changes in the abundance of nNOS mRNA were determined with a semiquantitative competitive polymerase chain reaction method. Blood pressure was significantly increased in rats 2, 3, and 4 weeks after the onset of intracerebroventricular aldosterone or 19-noraldosterone infusion compared with that in animals receiving vehicle. Subcutaneous infusion of either mineralocorticoid had no effect on blood pressure. Compared with controls, rats treated with aldosterone or 19-noraldosterone for 4 weeks showed significant decreases in the amount of nNOS mRNA in the hypothalamus and rostral and caudal ventrolateral medulla. These data suggest that reduced nNOS activity may contribute to the increase in blood pressure in rats with central mineralocorticoid-induced hypertension. 相似文献
15.
16.
Nusrat J. M. Sanghamitra Hiroshi Inaba Susumu Kitagawa Takafumi Ueno 《Journal of Inorganic and Organometallic Polymers and Materials》2013,23(1):50-60
In the last decade, there has been great deal of progress in the study of self-assembly processes of protein assemblies as biotemplates to create and construct one-dimensional arrays of nanocrystalline metals and semiconductors. Successful attempts in fabricating the protein-based bioelectronics could serve as a promising alternative to synthetic template based nanomaterials. Another perspective of protein assemblies is its use in the field of tissue engineering either as scaffold for cell adhesion and proliferation or as a foreign (bio)nanofunctionality to communicate with the macromolecules present in the extracellular or intracellular milieu and participate in the precise control of vital cell functions. Three-dimensionally arranged protein monomers to form bionanotubes are promising in terms of innate biocompatibility, easy bio-conjugation to incorporate multiple functionalities and well-defined nano-scale lengths. Such unique chemical properties of protein assemblies are described in this review. 相似文献
17.
Photocatalytic oxidation of methylpyridine isomers (2-methylpyridine, 3-methylpyridine, and 4-methylpyridine) was investigated
in a mixed solution of acetonitrile and water or acetonitrile using various kinds of TiO2 powders as photocatalysts. The main products from methylpyridine isomers were pyridinecarboxaldehyde isomers (2-pyridinecarboxaldehyde,
3-pyridinecarboxaldehyde, and 4-pyridinecarboxaldehyde). Rutile large TiO2 particles showed the highest level of activity for oxidation of 2-methylpyridine probably because band bending was necessary
for the oxidation of 2-methylpyridine. On the other hand, a fine particle having an anatase or rutile phase showed a higher
level of activity than large TiO2 particles for oxidation of 3-methylpyridine. A rutile fine particle showed the highest level of activity for the reaction.
It was found that pure rutile or pure anatase particles were inactive for oxidation of 4-mathylpyridine. If the particles
are not extremely small, pure rutile and pure anatase powders show fairly high levels of activity, and those containing both
anatase and rutile phases show the highest level of activity. The activity of pure rutile particles was also enhanced by physically
mixing them with a small amount of small anatase particles, which were inactive for this reaction. These results can be explained
by the synergism between rutile and anatase particles. All of these reactions effectively proceeded even under anaerobic conditions.
Photocatalytic reduction of methylpyridine isomers concomitantly proceeded on TiO2 particles under the conditions used. These results suggest that the activities of TiO2 photocatalysts for oxidation of methylpyridine isomers are dominated by the oxidation potential of alkylpiridine and band
bending of TiO2 particles. 相似文献
18.
C4+ and S4+-codoped titanium dioxide (TiO2) having a rutile phase was prepared. By doping C4+ and S4+ ions into a TiO2 lattice, the absorption edge of rutile TiO2 powder was largely shifted from 400 to 700 nm. 2-Methylpyridine and methyleneblue were photocatalytically oxidized at high efficiency on C4+ and S4+-doped TiO2 under visible light at a wavelength longer than 5 nm. 相似文献
19.
A new process for electrolytic production of a perfluorinated compound, (CF3)3N, using lanthanum nickel oxide-coated Ni sheet anode in the (CH3)4NF·4.0HF melt at room temperature, was developed. Thin films of the lanthanum nickel oxides were prepared on Ni sheets by sol-gel coating method using polyvinlylpyrrolidone(PVP). The main components of the thin films were La2O3, LaNiO3, and La2NiO4 at 500, 750 and 1000 °C, respectively. The anode performance in the (CH3)4NF·4.0HF melt depends greatly on the main component of the thin film, and the LaNiO3-coated Ni sheet anode gives the best anode performance. The potential of LaNiO3-coated Ni sheet anode remains constant at 5.9 V during electrolysis at 20 mA·cm−2 in the (CH3)4NF·4.0HF melt for 100 h. This is because LaNiO3 and NiF3, and/or Ni2F5, the latter of which was formed during electrolysis, in the film give a high electronic conductivity to the surface film during electrolysis. The maximum mole fraction of (CF3)3N (21.4%) was obtained at 20 mA·cm−2 in (CH3)4NF·4.0HF melt using the LaNiO3-coated Ni sheet. 相似文献
20.