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91.
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94.
认真学习和深刻领会科学发展观的丰富内涵和精神实质,要想全面推进“三基”工程建设,就要以科学发展观为统领,提高领导的执政能力,抓好三个“坚持”和四个“不放松”,才能推进警犬技术单位的基层基础建设。 相似文献
95.
一、利用警犬灵敏的听觉和嗅觉来执行巡逻、守候、警戒等任务,往往能起到事半功倍的效果。犬的听觉、嗅觉灵敏性很高,超过人很多倍,常常在我们还没有觉察出原因的情况下表现出警觉或吠叫报警,当我们在100米处模模糊糊听到声音时,警犬却能在1500米的远处听到人类听不到的那种超频音,可见用犬来执行警戒、巡逻、守候等任务是一种行之有效的方法。 相似文献
96.
海南省地处高温、潮湿的亚热带区域,各种霉菌易于繁殖生长,曲霉菌病也很多见,雏鸡感染发病通常在1~3周龄,而7日龄时大批量暴发较为少见. 相似文献
97.
Xanthophylls, a yellow pigment belonging to the carotenoid family, have attracted much attention for industrial applications due to their versatile nature. We report the isolation of a homo xanthophyll pigment-producing marine bacterium, identified as the Erythrobacter sp. SDW2 strain, from coastal seawater. The isolated Erythrobacter sp. SDW2 strain can produce 263 ± 12.9 mg/L (89.7 ± 5.4 mg/g dry cell weight) of yellow xanthophyll pigment from 5 g/L of glucose. Moreover, the xanthophyll pigment produced by the SDW2 strain exhibits remarkable antioxidative activities, confirmed by the DPPH (73.4 ± 1.4%) and ABTS (84.9 ± 0.7%) assays. These results suggest that the yellow xanthophyll pigment-producing Erythrobacter sp. SDW2 strain could be a promising industrial microorganism for producing marine-derived bioactive compounds with potential for foods, cosmetics, and pharmaceuticals. 相似文献
98.
99.
Ying Lv Guohe Huang Yongping Li Zhifeng Yang Wei Sun 《Water, air, and soil pollution》2012,223(1):443-465
Most of previous programming methods for air-quality management merely considered single pollutant from point sources. However,
air pollution control is characterized by multiple pollutants from various sources. Meanwhile, uncertain information in the
decision-making process cannot be neglected in the real-world cases. Thus, an inexact multistage stochastic programming model
with joint chance constraints based on the air quality index (air-quality management model with joint chance constraints (AQM-JCC))
is developed for controlling multiple pollutants deriving from point and mobile sources and applied to a regional air-quality
management system. In the model, integrated air quality associated with the joint probability existing in terms of environmental
constraints is evaluated; uncertainties expressed as probability distributions and interval values are addressed; risks of
violating the overall air-quality target under joint chance constraints are examined; and dynamics of system uncertainties
and decision processes under a complete set of scenarios within a multistage context are reflected. The results indicate that
useful solutions for air quality management practices in sequential stochastic decision environments have been generated,
which can help decision makers to identify cost-effective control strategies for overall air quality improvement under uncertainties. 相似文献
100.
Peng XW Ren JL Zhong LX Peng F Sun RC 《Journal of agricultural and food chemistry》2011,59(15):8208-8215
Exploitation of biomaterials derived from renewable resources is an important approach to address environmental and resource problems in the world today. In this paper, novel ionic hydrogels based on xylan-rich hemicelluloses were prepared by free radical graft copolymerization of acrylic acid (AA) and xylan-rich hemicelluloses (XH) by using N,N-methylene-bis(acrylamide) (MBA) as cross-linker and ammonium persulfate/N,N,N',N'-tetramethylethylenediamine (APS/TMEDA) as redox initiator system. The network characteristics of the ionic hydrogels were investigated by Fourier transform infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM), as well as by determination of mechanical properties, swelling, and stimuli responses to pH, salts, and organic solvents. The results showed that an increase in the MBA/XH or AA/XH ratio resulted in higher cross-linking density of the network and thus decreased the swelling ratio. Expansion of the network hydrogels took place at high pH, whereas shrinkage occurred at low pH or in salt solutions as well as in organic solvents. The ionic hydrogels had high water adsorption capacity and showed rapid and multiple responses to pH, ions, and organic solvents, which may allow their use in several areas such as adsorption, separation, and drug release systems. 相似文献