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111.
经总酶活性测定和凝胶电泳图谱分析发现:剧烈运动后,小白鼠六种组织LDH总酶活性,骨骼肌有显著升高,(p<0.05),其余五种组织均变化不显著;心肌、骨骼肌、肾脏的M型LDH相对活性显著升高(P<0.05),而H型LDH相对活性显著下降(p<0.05);相应地,A亚基比例显著升高,B亚基比例显著下降,这种变化似能反应剧烈运动对小白鼠厌氧代谢的明显影响.  相似文献   
112.
油井流入动态是油井举升优化设计的基础 ,目前国内外研究油井流入动态的方法有多种 ,但是各有其不足和局限性 .为此利用模拟退火方法进行油井流入动态方法研究 .与以往的近似算法相比 ,该方法不需要将单相流和多相流分开讨论 ,且无任何假设条件 ,适用范围广 ;通过实例 ,把模拟退火的预测的产量结果与利用 Vogel方程所预测的产量结果进行比较和误差分析 ,结果表明 ,该算法的误差是非常小的 .因此 ,利用该算法研究油井流入动态非常可行 .  相似文献   
113.
石墨炉原子吸收光谱法间接测量尿样中氨基多糖含量   总被引:2,自引:0,他引:2  
本文采用阿利新蓝(AlcianBlue)与尿样中氨基多糖(以下称GAG)在pH=5.8的醋酸钠溶液中,发生沉淀反应生成GAG铜复合物。离心分离沉淀物,以石墨炉原子吸收光谱测定沉淀物中铜含量,间接计算GAG含量。本文对尿样加入染液浓度,沉淀反应平衡时间;沉淀物的洗涤剂、洗涤次数等进行了探讨,确定了最佳实验条件,实测了60例健康人尿中GAG含量,与文献报导值一致。  相似文献   
114.
Affective property of image and fractal dimension   总被引:3,自引:0,他引:3  
Affective information processing is an advanced research direction in the AI world. Affective Information of image was taken as the objective of research in this paper. The influence of color vision properties’ histograms of image on human emotions was analyzed. Then based on fractal theory, the fractal aspect of different kinds of images was analyzed in keeping with the space domain. After that, psychological testing method of semantic difference was applied to verify the uniformity of the objective and subjective evaluations. At last, a conclusion was drawn that image having different affective properties could be classified by their fractal dimensions.  相似文献   
115.
116.
一种局部相含率测量方法   总被引:2,自引:0,他引:2  
在局部电导探针和单丝电容探针的基础上,提出一种新型局部电容探针,用于测量两相流的局部相含率。静态研究表明,局部电容探针能够测量空气水两相流的局部相含率,测量结果不受导电相电导率变化的影响。从工业蒸馏水变化到饱和食盐水(NaCl的质量分数0~5%),局部电容探针输出结果没有明显变化。电极距离在0~30 mm的范围内变化,测量结果变化小于1%。动态实验表明,局部电容探针测量的两相流的局部相含率,能够很好反映流动过程(以弹状流为例),和实验观察结果完全一致。只需要设置简单的阈值大小,就可以得到相含率的大小。  相似文献   
117.
Exciton states and optical properties in wurtzite (WZ) InGaN/GaN quantum well (QW) are investigated theoretically, considering finite barrier width and built-in electric field effects. Numerical results show that when the barrier width increases, the ground-state exciton binding energy, the interband transition energy and the integrated absorption probability increase first and then they are insensitive to the variation of the barrier width. For any barrier width, the ground-state exciton binding energy and the integrated absorption probability have a maximum when the well width is 1 nm; moreover, the integrated absorption probability goes to zero when the well width is larger than 6 nm. In addition, the competition effects between the built-in electric field and quantum confinement are also investigated in the WZ InGaN/GaN QW.  相似文献   
118.
Rutile and anatase titanium dioxide (TiO(2)) powders were used as sonocatalysts for the degradation of methyl orange which was used as a model compound. Ultrasound was used as an irradiation source. It was found that the sonocatalytic degradation ratios of methyl orange in the presence of TiO(2) powder were much better than ones without any TiO(2), but the sonocatalytic activity of rutile TiO(2) particles was obviously higher than that of anatase TiO(2) particles. Although there are many factors influencing sonocatalytic degradation of methyl orange, the experimental results show that the best degradation ratio of methyl orange can be obtained when the experimental conditions of the initial methyl orange concentration of 10 mg/l, rutile TiO(2) added amount of 500 mg/l, ultrasonic frequency of 40 kHz, output power of 50 W, pH=3.0 and 40 degrees C within 150 min were adopted. In addition, the catalytic activity of reused rutile TiO(2) catalyst was also studied and found to be better than new rutile TiO(2) catalyst sometimes. All experimental results indicated that the method of the sonocatalytic degradation of organic pollutants in the presence of TiO(2) powder was an advisable choice for treating non- or low-transparent organic wastewaters.  相似文献   
119.
The effects of vacuum-induced coherence (VIC) on the properties of the absorption and gain of the probe field in an equispaced three-level ladder atomic system are investigated. It is found that lasing without inversion (LWI) is remarkably enhanced due to the effect of VIC in the case of the small incoherent pump rate.  相似文献   
120.
The rheological behaviors of polypropylene (PP)/poly(1-butene) (PB) blends with homo-polypropylene (PP1) or impact polypropylene (PP2), a poly(propylene-co-ethylene) as the PP component were studied. With increasing of PB resin content for both PP/PB blends, the blends showed higher G'(ω), G''(ω) and η*(ω) at low frequencies but lower values at high frequencies which implied that the processability was improved. A two-phase morphology was observed through the various rheological responses, including G'(ω)-ω terminal region curves, Cole-Cole plots and the weighted relaxation spectra with the PB contents up to 40?wt%. With the same PB content, the rheological parameters of the PP2/PB blends were quite different from those of the PP1/PB, which can be attributed to the stronger interaction between PB chains and the ethylene-co-propylene copolymer in PP2. The impact strength of the PP2/PB blends was improved dramatically over that of the PP1/PB. The more significant toughening effect for the PP2/PB blends can be attributed to the special responses of its rheological behaviors.  相似文献   
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