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101.
102.
Anaerobic biodegradation tests of poly(lactic acid) (PLA) powder were done at the thermophilic (55 °C) and mesophilic temperature (35 °C) under aquatic conditions [total solid concentrations of the used sludge were 2.07% (at 55 °C) and 2.24% (at 35 °C)] using a newly developed evaluation system. With this system, the evolved biogas is collected in a gas sampling bag at atmospheric pressure. This method is more convenient than using a pressure transducer or inverted graduated cylinder submerged in water. PLA was degraded about 60% in 30 days, about 80% in 40 days and about 90% in 60 days at 55 °C. On the other hand, the PLA degradation started in 55 days at 35 °C and degradation rate was much slower than at 55 °C.  相似文献   
103.
Developers used in photolithography contain toxic tetramethylammoniumhydroxide (TMAH) and this creates a problem of how to properly treat developer wastewater. We have developed a TMAH wastewater treatment technique that consists of a combination of two novel decomposition processes: pyrolyzing TMAH to TMA and decomposing TMA to N 2, H2O, and CO2 by means of a selective oxidation catalyst for nitrogenous compounds. We have tested a system using this technique in long-term treatment of the actual wastewater and have found it to be sufficiently practical. The running cost of a treatment system using our technique would be about one-ninth that of disposing of the wastewater as industrial waste but about 2.3 times that of biological treatment. Compared with biological treatment, however, our system is tolerant to many treatment conditions and operation management is much easier. Furthermore, it occupies only about one-sixth the area of a biological treatment system  相似文献   
104.
The effects of electrical stimulation, applied to the superior salivatory nucleus (SSN) or the cervical sympathetic nerve, on vascular permeability in nasal mucosa were studied in 16 cats. Plasma extravasation was quantified by using Evans blue. Vascular permeability in the cat nasal mucosa was increased by the electrical stimulation of SSN. Plasma extravasation induced by SSN stimulation was reduced by administration of nitric oxide synthase (NOS) antagonist, N(omega)-nitro-L-arginine methyl ester (L-NAME). Administration of atropine did not affect increased vascular permeability by SSN stimulation. We conclude that neurogenic plasma extravasation in cat nasal mucosa evoked by the parasympathetic nerve is not mediated by cholinergic fibers but rather by nitric oxide.  相似文献   
105.
106.
Bifunctional fibers containing phosphonate and sulfonate were derived from chloromethylstyrene grafted polyolefin fibers (PPPE-g-CMS) by phosphorylation and subsequent sulfonation reactions. It was clarified that phosphorylation of PPPE-g-CMS by Arbusov reaction is more suitable than one by the reaction with PCl3 in the presence of AlCl3, because the latter damaged fibers and gave phosphinate groups in addition to phosphonate ones. Then, bifunctional fibers containing phosphonate and sulfonate groups were prepared by sulfonation of monofunctional phosphonate fibers obtained via Arbusov reaction with chlorosulfonic acid. The metal ion selectivity of the bifunctional fibers was governed by both phosphonate and sulfonate groups. In addition, bifunctional fibers gave much more excellent kinetic performances in column-mode uptake of Cu(II) than the monofunctional phosphonate fibers and resin.  相似文献   
107.
The front steering angle control and its integration with the direct yaw moment control are suggested to enhance the handling performance for heavyduty vehicles based on a 3D vehicle modelThe doublecostf unction LQR methodology (DLQR) which extends the concept and the applicable field of LQR to express the practical requirements more plainly,is proposed to determine the control input value:compensation value of front steering angle in the optimal model A simple autotuning proportion controller is employed in direct yaw moment control to regulate the moment timely The simulation results show that front steering angle control using DLQR,has good ability to achieve the desired steering output in the different running conditionsDLQR is more powerful to balance many factors effectively based on the explicit mathematics expression of the physics of the problem than LQR does  相似文献   
108.
109.
This paper is concerned with systematic developments of the Fraunhofer-diffraction method for studies of plasma density fluctuations in high-temperature plasmas using infrared lasers, namely (i) development of the general theory of the Fraunhofer-diffraction method, (ii) measurements of fluctuations propagating in an azimuthal direction, (iii) measurements of fluctuation intensities, and (iv) application in measurements on high-temperature plasmas.  相似文献   
110.
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