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71.
厌氧消化技术在日本有机废水和废弃物处理中的应用   总被引:1,自引:0,他引:1  
日本污泥厌氧消化始于1932年,目前污泥厌氧消化工程已超过300个,消化池总容积达210×10<'4>m<'3>.目前,全日本共有300多座升流式厌氧污泥床反应器(upflow anaerobic sludgebed,UASB)和膨胀颗粒污泥床(expanded granular sludge bed,EGSB)处理厂,主要用于包括啤酒废水、软饮料废水、酿酒废水、食品加工废水和化工废水在内的高浓度有机工业废水的处理.总结了厌氧消化技术在日本有机废水和有机废弃物处理中的应用状况,以及运行参数.此外,对日本厌氧消化技术在厌氧膜生物反应器、产氢产甲烷两段发酵和沼气生物脱硫等方面的新进展也进行了介绍.  相似文献   
72.
Abstract

We have already fabricated honeycomb-patterned cellulosic films with cellulose I and II polymorphisms as a basal framework in order to create an artificial woody cell wall.[ 1 Nemoto, J., Uraki, Y., Kishimoto, T., Sano, Y., Funada, R., Obata, N., Yabu, H., Tanaka, M. and Shimomura, M. 2005. Production of mesocopically patterned cellulose film. Bioresour. Technol., 96: 19551958.  [Google Scholar] , 2 Uraki, Y., Nemoto, J., Otsuka, H., Tamai, Y., Sugiyama, J., Kishimoto, T., Ubukata, M., Yabu, H., Tanaka, M. and Shimomura, M. 2007. Honeycomb-like architecture produced by living bacteria, Gluconacetobacter xylinus. Carbohydr. Polym., 69: 16. [Crossref], [Web of Science ®] [Google Scholar] ] The adsorption of an isolated lignin, acetic acid lignin (AL), was attempted onto the honeycomb films not only to develop materials further mimicking the cell wall but also to elucidate the mechanical effect of isolated lignin on the tensile strength of the cellulosic architecture. The tensile strengths of honeycomb-patterned cellulosic films were improved by the AL adsorption. Although the cellulosic films without lignin weakened under high moisture content conditions as compared with those under the low content conditions, the lignin-adsorbed cellulosic film maintained significant tensile strength even under the high content conditions. This result suggests that lignin contributes to reinforce the mechanical strength of cellulose framework, in particular high moisture conditions.  相似文献   
73.
An extreme ultraviolet (EUV) interference lithographic exposure tool was installed at the long undulator beamline in NewSUBARU to evaluate EUV resists for 25 nm node and below. The two-window transmission grating of 40 and 50 nm half pitch (hp) were fabricated with techniques of spattering, electron beam lithography, dry etching and wet etching. hp patterns (20 and 25 nm) of chemically amplified resist (CAR) and non-CAR were successfully replicated using the EUV interference lithographic exposure tool.  相似文献   
74.
The shear-stress dependence of the shear modulus in concentrated solutions of acrylonitrile copolymer was investigated by the capillary end-correction method. The shear modulus decreases with an increase of shear stress above a critical polymer concentration at ti higher shear rate than that at which the decrease of the viscosity begins to occur. The non-Hookian behavior of the concentrated solutions may be considered to arise from the breakdown of the tangled network structure, namely elastically deformable pseudo network.  相似文献   
75.
Yoshikawa Y  Umeki T  Mukae T  Torii Y  Kuga T 《Applied optics》2003,42(33):6645-6649
We present a simple modulation-free technique to stabilize a laser frequency to the Doppler-free spectra of an atomic vapor. Polarization spectroscopy with use of a balanced polarimeter allows us to obtain a background-free dispersion signal suitable for high-speed and robust frequency stabilization. We employed the method to the 5S(1/2) F = 2 --> 5P(3/2) F' = 3 transition of 87Rb atoms. The achieved feedback bandwidth was approximately 100 kHz, and an efficient suppression of the frequency noise in a laboratory environment was attained.  相似文献   
76.
Surface-nanofabrication using probe oxidation is presented. Electrochemically generated oxide nano ridge structures can be fabricated using probes for atomic force microscopy. Moreover, removing the oxide ridge by hydrofluoric acid etching can also produce nanogroove structures. The relationship between the nanostructure shapes and fabrication conditions such as applied voltage and radius of curvature of the probe was investigated. The height of the oxide ridge can be controlled with sub-nanometer accuracy by the applied voltage and the width can be controlled by the tip radius. The depth and width of the groove can be controlled by adjusting the height and width of the ridge. Nanostructures with a very small height or depth (about 50 nm wide and < 1 nm high or deep) can be fabricated by our method. This is very useful for clarifying the nanotribology of micro- or nanomechanical devices.  相似文献   
77.
78.
Photoinduced electron-transfer and hole-migration processes for newly prepared copolymers of C60 and N-vinylcarbazole (VCz) with the several compositions have been investigated using time-resolved fluorescence and absorption methods. Shortening of fluorescence lifetime of the C60 moiety in PVCz-C60 was observed, suggesting that the charge-separation takes place via the excited singlet state of C60; the rate constants of the charge-separation were evaluated to be larger than 10(9) S(-1) in polar solvents. In the nanosecond transient absorption spectra in the visible and near-IR regions obtained by excitation of the C60 moiety, the generation of PVCz(*+)-C60(*-) was confirmed. The time profiles of these radical ions showed slow decay continuing more than 800 micros in polar solvents. From the simulations of the decay curves on the basis of the proposed kinetic model, in which the charge-recombination takes place competitively with hole-migration, the rate parameters have been evaluated; i.e., the rate constant of hole migration was evaluated to be 5 x 10(7) s(-1), which was 50 times faster than that of the charge-recombination (ca. 10(6) s(-1)) in polar solvent. The charge-recombination takes place after hole migration among 200-300 Cz units along the PVCz chain in PVCz-C60.  相似文献   
79.
Field surplus nitrogen (N) and farm disposal N are major sources of water pollution in farming systems. These sources are estimated from N budgets in field and whole farms, which are associated with the production and consumption of food. This study was conducted to evaluate these two pollution sources in the steep mountainous karst region of Quibainong, Guangxi Province, southern China. The region is, characterized as an area of upland farms, due to the shallow soils and rapid water drainage through cracks in the limestone. Although field surplus N in 1960 was only 4.1 kg N ha–1, current field surplus N ranged from 10.1 to 463 kg N ha–1, with values above 50 kg N ha–1 in farms along roads and less than 40 kg N ha–1 in the farms away from roads. The results obtained in near-road farms were similar to those in a previous study of N budgets in China. There was a significant positive correlation between the field surplus N and N application rate, including when the previous data were incorporated. The proportion of manure to total N application decreased with increase of N application. Chemical fertilizer was applied in greater quantity in economically rich farms. Therefore, the increase of field surplus N in Quibainong may be caused by economic improvement. Although livestock and human excreta were stocked in manure barns, unused excreta N increased with the increase of N excreted. The unused excreta N also increased with the decrease of feed self-sufficiency, but was not related to N application rate. These facts indicate that livestock husbandry in Quibainong is related to economic status of farms, but independently of crop production.The N application rate of more than 160 kg N ha–1 increased field surplus N to an extent greater than crop uptake N, and a N application rate of more than 185 kg N ha–1 increased the potential nitrate-N concentration to more than 10 mg L–1. Therefore, 160–185 kg N ha–1 is suggested to be the environmental capacity to sustain optimal N cycling in Quibainong. The average value of excreta N produced on near-road farms in Quibainong was 171 kg N ha–1. If excreta N was used evenly for crop cultivation without chemical fertilizer in whole fields, the optimal N cycling would be maintained.The survey conducted here using a questionnaire was effective in evaluating all kind of N flows in the farming systems.  相似文献   
80.
Histone deacetylase inhibitors (HDACis) are one of the therapeutic options for cutaneous T-cell lymphoma (CTCL), but they have limited effects. We previously demonstrated that HSP72 overexpression is associated with chemoresistance to HDACis in lymphoma cells. The purpose of this study was to investigate whether the functional depletion of HSP72 enhances the effect of the HDACi vorinostat. First, we established a stable HSP72-knockdown CTCL cell line and confirmed the influence of HSP72 reduction on the antitumor effects of vorinostat. Next, we studied the effect of quercetin, an inhibitor of HSP72, on the antineoplastic effects of vorinostat. In five CTCL cell lines examined, HSP72 expression was highest in Hut78 cells, and HSP72 knockdown enhanced vorinostat-induced apoptosis in these cells. Low-dose quercetin reduced HSP72 expression, increased HDAC activity, and enhanced vorinostat-induced suppression of Hut78 cell proliferation. A single low dose of quercetin induced G2 arrest and only slightly increased the sub-G1 cell fraction. Quercetin also significantly enhanced vorinostat-induced apoptosis, caspase-3, caspase-8, and caspase-9 activity, and the loss of mitochondrial membrane potential. HSP72 knockdown enhanced vorinostat-induced apoptosis in an HSP72-overexpressing CTCL cell line, and thus, quercetin may be a suitable candidate for combination therapy with vorinostat in clinical settings.  相似文献   
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