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1.
Food Science and Biotechnology - Aluminum based reflective nanolens arrays were developed via a series of aluminum electropolishing and anodization steps with subsequent selective dissolution of... 相似文献
2.
Chaoxin Li Yi Zhou Yuming Tian Yuanyuan Zhao Kaiyue Wang Guomin Li Yuesheng Chai 《Ceramics International》2019,45(5):5613-5616
Ceramics with mullite whiskers were prepared from coal fly ash and Al2O3 raw materials, with AlF3 used as an additive. The phase structures and microstructures of the ceramics were identified via X-ray diffraction and scanning electron microscopy, respectively. The results show that pickling of coal fly ash is an effective method for enhancing the flexural strength of ceramics. Sintering temperature and AlF3 addition were also key factors influencing the creation of ideal ceramics. The ceramic made from pickled coal fly ash, 6?wt% AlF3, and sintered at 1200?°C, exhibited the highest flexural strength of 59.1?MPa, and had a bulk density of 1.32?g/cm3 and porosity of 26.8%. The results show that ceramic materials made under these conditions are ideal candidates for manufacturing ceramic proppants for the exploitation of unconventional oil and gas resources. 相似文献
3.
Junlan Chai 《中国耐火材料》2018,(1)
正Four issues per volume a year,CHINA’S REFRACTORIES is distributed worldwide by airspeed delivery at no extra cost to subscribers. 相似文献
4.
对己二腈工业反应器提出了两釜串联带回流的模型,通过模拟计算得出模型的级间返混系数 f=6的结论。该模型能较好地预测工业反应器中物料组分浓度变化和气、液两相的流动特性;指出了现工业反应器的鼓泡中和段体积偏小是造成己二酸浓度偏高的关键;提出了可以通过增加串连一个鼓泡预反应段的改造方案,能有效地降低己二酸的浓度,从7%降至4%左右,从而能较好地减缓腐蚀和结焦。 相似文献
5.
Lead content of rice collected from various areas in the world 总被引:1,自引:0,他引:1
ZW Zhang CS Moon T Watanabe S Shimbo M Ikeda 《Canadian Metallurgical Quarterly》1996,191(1-2):169-175
Rice samples consumed by local populations were collected between 1990 and 1995 in 17 areas in the world, mostly from Asia (10 areas), but also from 7 areas outside of Asia. In total, 1528 samples were obtained (about one half from Japan) and were analyzed for lead (Pb) by electrothermal atomic absorption spectrometry. When the Pb contents in rice samples were classified into 10 areas in Asia, the highest and the lowest geometric means (GMs) were for Indonesia (38 ng/g) and Australia (2 ng/g), respectively. Among 7 regions outside Asia, the GM was highest for Spain (58 ng/g) and the lowest for the USA. (3 ng/g). Moreover, inter-regional differences were significant, when more than 100 samples from one area were divided into 3-9 regions and GMs for regions were compared. There was a marked difference in Pb contents in rice by areas and regions in the world. Nevertheless, comparison by area of the present results with those reported in literature show that there has been no substantial reduction in Pb in rice in the past decade either in Japan or elsewhere in the world. 相似文献
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7.
Pre-transplant nephrectomy was done in a 25-year-old man for calculous pyelonephritis using a retroperitoneal laparoscopic approach with a newly devised ligature applicator-dissector- kidney retractor. 相似文献
8.
E Bazopoulou-Kyrkanidou P Neou CS Bartsocas S Kyrkanides I Fanourakis 《Canadian Metallurgical Quarterly》1995,6(3):227-232
PURPOSE: To select ideal radiologic projections for mapping and ablation of tachycardias of right ventricular outflow tract (RVOT). METHODS: Ten hearts from human corpses were studied utilizing radiopaque material to identify the pulmonary valve and three distinct sites on this valve: septal anterior (A), septal posterior (P) and free-wall (L). Next, the hearts were filmed in the frontal plane and in oblique projections with 15 degrees increments to the right and to the left. The projections in which the sites were lateralized on the valve, eased radiologic interpretation and were considered ideal for mapping and ablation. Depending on the proximity of the sites to the lateral extremes of the pulmonary valve, the projections were considered ideal ( ), intermediary (++) and inadequate (+). RESULTS: Projections [table: see text] CONCLUSION: The A site of RVOT was best indicated in the 60 and 45 degrees left anterior oblique projections; the 0 degree postero anterior projection was best for mapping the P site; the L region was best explored in the 60 degrees right anterior oblique projection. 相似文献
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10.
The occurrence of fungi was investigated in the gut of 200 common garden lizards (Agama agama). The most important pathogenic fungus isolated was Basidiobolus haptosporus, an aetiological agent of subcutaneous zygomycosis. It was recovered from the intestinal contents of 112 (56%) lizards. Other important fungi isolated included Aspergillus spp. in 24 (12%) lizards, Candida spp. in 12 (6%), Penicillium spp. in 12 (6%) and Fusarium spp. in 12 (6%). Mucor spp. were isolated from eight (4%) male lizards only. Agamid lizards are plentiful in rural and urban areas of Nigeria. As they live in close vicinity to man, they are likely to play an important role in the spread of disease that may be caused by these fungi and its transmission to man. None of the animals investigated that yielded fungal cultures revealed any external fungal infection. 相似文献