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991.
为提高纺织钢令的耐磨性,对其表面进行碳氮共渗处理.通过分析气氛中不同碳势模式控制的特点,确定了20钢碳氮共渗的工艺参数.根据碳氮质量分数、残余奥氏体质量分数,以及合金元素内氧化对纺织钢令显微硬度的影响,设计了碳势控制系统.系统运行后取得了满意的控制效果. 相似文献
992.
针对具有可控机动能力的无线传感器网络的自部署问题,提出了一种用于未知环境的移动传感器网络自部署算法.该算法结合人工势场法与确定度网格方法,用确定度来对障碍物进行抽象的表达,通过活动窗口单元的虚拟排斥力来迫使网络扩展、仿真实验结果表明,该算法可以有效地用于移动传感器网络的自部署,网络覆盖面积在部署完成时会有显著的增长. 相似文献
993.
张小云 《四川师范大学学报(自然科学版)》2006,(6)
讨论了带斯塔克势的非线性Schrd inger方程爆破解的定性性质,运用一个变量替换建立了带斯塔克势的非线性Schrd inger方程与不带势的经典非线性Schrd inger方程之间的联系.结合经典非线性Schrd inger方程的性质,进一步研究了临界的带斯塔克势的非线性Schrd inger方程爆破解的结构,证明了其爆破解具有L2集中性质.特别地,当初始值条件径向对称时,证明了原点O为集中点. 相似文献
994.
SONG Weiqun LUO Yueji CHI Song JI Xunming LING Feng ZHAO Lun WANG Maobin SHI Jiannong 《自然科学进展(英文版)》2006,16(10):1045-1050
The visual spatial attention mechanism in the brain was studied in 16 young subjects through the visual search paradigm of precue-target by the event-related potential (ERP) technique, with the attentive ranges cued by different scales of Chinese character and region cues. The results showed that the response time for Chinese character cues was much longer than that for region cues especially for small region cues. With the exterior interferences, the target stimuli recognition under region cues was much quicker than that under Chinese character cues. Compared with that under region cues, targets under Chinese character cues could lead to increase of the posterior P1, decrease of the N1 and increase of the P2. It should also be noted that the differences between region cues and Chinese character cues were affected by the interference types. Under exterior interferences, no significant difference was found between region cues and Chinese character cues; however, it was not the case under the interior interferences. Considering the difference between the exterior interferences and the interior interferences, we could conclude that with the increase of difficulty in target recognition there was obvious difference in the consumption of anterior frontal resources by target stimuli under the two kinds of cues. 相似文献
995.
采用分子动力学和EAM(embedded atom method)势,模拟研究了热脉冲对金属铜从晶态到非晶态转变的影响.计算结果表明,热脉冲作用下,转变时体系平均温度高于平衡计算熔点,结构转变是过热熔化过程,系统不可能发生从晶态到非晶态非平衡转变.随着热脉冲频率的增大,转变所需热脉冲幅度减小,体系转变过热度降低. 相似文献
996.
盐酸溶液中乌鲁托品对钢的缓蚀性能 总被引:2,自引:0,他引:2
用电化学阻抗谱(EIS)和开路电位测量法(OCPM)研究了在1 mol·L-1盐酸溶液中乌鲁托品(UP)与45#钢的界面吸附及缓蚀行为.EIS表明:随着缓蚀剂UP浓度的增大,吸附膜逐渐形成,电荷传递电阻增大.在缓蚀剂浓度为0.01 mol·L-1时,缓蚀效率出现最大值;大于该浓度时,缓蚀效率下降.OCPM表明:加缓蚀剂UP前后体系自腐蚀电位的改变与温度的倒数呈线性关系.UP对阳极过程有抑制作用,是阳极型缓蚀剂;吸附热为-35 kJ/mol,吸附形式为物理吸附. 相似文献
997.
《科学通报(英文版)》2006,51(Z1)
Combined with materials measured on leaves water potential of Populus euphratica oliv in the process of ecological water delivery in the lower reaches of Tarim River, the influence of ground-water depths and soil salinity on leaves water potential of P. euphratica was analyzed. We found that there was evident negative correlation between the leaves water potential of P. euphratica and ground-water depths. The deeper the ground-water depths were, the lower the leaves water potential of P. euphratica was, the more serious drought stress P. euphratica suffered from. Besides, there was evident negative correlation between the soil salinity and the leaves water potential of P. euphratica. The bigger the soil salinity was, the lower the leaves water potential of P euphratica was, the more serious drought stress was indicated from which P. euphratica suffered. For sections rather distant for Daxihaizi Reservoir as well as for those places of wells rather distant from the river course, ground-water depths and the soil salinity were high; the leaves water potential of P. euphratica was low. The leaves water potential of P. euphratica can reflect the degree at which P. euphratica suffers from drought and salt stress, and has an important reference meaning in analyzing proper ground-water depths for the survival and growth of P. euphratic in the lower reaches of Tarim River. 相似文献
998.
Protein-protein recognition is an important step in biological processes, which still largely remains elusive. The inter-residue contact potential, CPij, describes the propensity of contact between two types of residue. In this study, several different CPij variants were examined with the objective of discriminating the binding potential of surface pairs. Using solvent mediated inter-molecule contact potential (SM-IMCPij), an evaluation model was deduced and tested. Using the evaluation model it was found that the SM-IMCPij gives a better performance than either residue mediated IMCPij(RM-IMCPij) or folding-residue contact potential (FCPij). The results suggest that the evaluation model provides a fast, effective, and discriminative method for the evaluation of proposed binding interfaces. 相似文献
999.
植物水势系数及其应用实例 总被引:5,自引:0,他引:5
本文提出了植物水势系数的概念与计测公式,即植物水势系数是植物水势占大气水势和土壤水势对植物水势产生直接影响力那部分水势之和的比值。并对在塔克拉玛干沙漠生长的沙生柽柳进行了应用实例的验证。结果表明,在自然状态下,植物水势系数可作为衡量植物对环境胁迫反应强弱的一个指标。 相似文献
1000.
精确求解了一种新的一维势能,其为一维三角势的超对称伴随势,得出了此势的本征能量及对应的定态波函数,求解的推导过程与一般的超称量子力学求解方法有所不同。 相似文献