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271.
To develop a low cost and energy-saving wastewater treatment technique in combination with resource recycling and amenity functions, we constructed a plant bed filter ditch in which useful terrestrial and aquatic plants can be utilized for nitrogen and phosphorus removal from wastewater. Screening studies were conducted to evaluate and compare the effectiveness of 20 kinds of plant species which are economically important or exhibit on aesthetic value, including 13 terrestrial species, for domestic wastewater treatment. Artificial wastewater containing 20 mg L-1 of Nand 3.3 mg L-1 of P, was supplied to the ditch at the rate of about 1.41–2.08 g m-2 d-1 for N and 0.20–0.33 g m-2 d-1 for P. The experiments were performed in a glass house with windows opened from April to November. The ditches showing high Nand P removal rates were planted with plants which exhibited high biomass production rates. In the case of the papyrus ditch, Nand P removal rates exceeded 0.8 g m-2 d-1 for N and 0.15 g m-2 d-1 for P from late spring to autumn, in the case of the kenaf ditch and sorghum ditch, from summer to autumn and in the case of the Italian ryegrass ditch and barley ditch, in early spring. These findings indicated that efficient wastewater treatment can be performed consistently except in the winter season, by cultivating these plants in an appropriate combination in the ditches. 相似文献
272.
273.
Yasuo Suto 《Journal of Forest Research》1997,2(1):59-65
In order to confirm the pathogenicity ofCistella japonica, inoculation experiments were conducted onto several coniferous trees. Resinous lesions similar to those of the resinous
stem canker developed by the inoculation withCi. japonica only onChamaecyparis obtusa. Chamaecyparis trees were heavily affected when inoculated with the fungus in November, but slightly in May and August. Resin flows occurred
when inocula ofCi. japonica were put into the holes made on stem barks and on pruning scars. Isolates ofCi. japonica varied greatly in the pathogenicity. On the lesions caused by the fungus, resinous and necrotic areas expanded in fusiform
or oblong shape, and resin cysts were formed in inner barks. Beneath some necrotic inner barks, sapwood was suppressed in
growth for the damages in cambial cells and stained.Ci. japonica was reisolated from the inoculated lesion tissues, though isolation frequency of the fungus became lower in some lesions
two or more years after the inoculation. The results of these inoculations proved thatCi. japonica was the causal agent of the resinous stem canker ofCh. obtusa. 相似文献
274.
Dede Hermawan Toshimitsu Hata Shuichi Kawai Wakatsu Nagadomi Yasuo Kuroki 《Journal of Wood Science》2002,48(1):20-24
This study dealt with the effects of a curing method that uses gaseous and supercritical CO2. Its effects on the properties of oil palm fronds cement-bonded board manufactured by the conventional cold-press setting method were recorded. The effect of MgCl2 as an accelerator of cement setting was also investigated. The hydration of cement was examined using X-ray diffractometry, thermal gravimetry, and scanning electron microscopy. The results are as follows. (1) High-performance cement-bonded boards made from oil palm fronds were successfully manufactured using the CO2 curing method. (2) The curing method using either gaseous or supercritical CO2 resulted in accelerated curing of cement (within several minutes). Accelerated formation of the hydration products (e.g., calcium carbonate and calcium silicate) is the main reason for the high strength of CO2-cured boards. (3) The CO2 curing technology does not require setting accelerators, which cause a decrease in the dimensional stability of cement-bonded board. 相似文献
275.
Konosuke OTOMARU Takuro FUJIKAWA Yasuo SAITO Takaaki ANDO Takeshi OBI Naoki MIURA Chikara KUBOTA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(9):1191-1193
A 10-month-old Japanese black heifer was diagnosed as having an intra-abdominal
cyst using computed tomography (CT). Through a posterior ventral midline incision, the
cyst was removed, and the heifer completely recovered after the surgery. CT scans enabled
detection of the intra-abdominal cyst and measurements of the diameter of the cyst before
the surgery. 相似文献
276.
277.
Immunolocalization of steroidogenic enzymes in equine fetal adrenal glands during mid-late gestation
Weng Q Tanaka Y Taniyama H Tsunoda N Nambo Y Watanabe G Taya K 《The Journal of reproduction and development》2007,53(5):1093-1098
To elucidate the relationship between steroidogenic hormones and developing adrenal glands, we investigated the immunolocalization of steroidogenic enzymes in equine fetal adrenal glands during mid-late gestation. Fetal adrenal glands were obtained from three horses at 217, 225 and 235 days of gestation. Steroidogenic enzymes were immunolocalized using polyclonal antisera raised against bovine adrenal cholesterol side-chain cleavage cytochrome P450 (P450scc), human placental 3beta-hydroxysteroid dehydrogenase (3betaHSD), porcine testicular 17alpha-hydroxylase cytochrome P450 (P450c17) and human placental aromatase cytochrome P450 (P450arom). Histologically, cortex and medulla cells were clearly observed in the three fetal adrenal gland tissue samples. P450scc and P450c17 were identified in cortex cells close to medulla cells and in some medulla cells in the fetal adrenal glands. P450arom was present in both cortex and medulla cells in the fetal adrenal glands. However, 3betaHSD was not found in any of the equine fetal adrenal gland tissue samples. These results suggest that equine fetal adrenal glands have the ability to synthesize androgen and estrogen, which may play an important physiological role in the development of equine fetal adrenal glands. 相似文献
278.
Chitinase and N-acetylglucosaminidase activities in forest soils were examined by a highly sensitive method using 4-methylumbelliferyl (4MU) derivatives of N-acetyl-D-glucosamine oligomers as substrates. The method involves the fluorometric estimation of the 4-MU released through the activity of the soil enzymes when a soil sample and the substrate are incubated in a buffer. The activities of both enzymes decreased markedly with depth in the 4 forest soil profiles studied (i.e. Andosol, Podzol, 2 Cambisols). The activities of these soil enzymes were highly correlated with the carbon and nitrogen content of the soils. 相似文献
279.
280.