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101.
Y. Z. Liu X. T. Zu J. Lian L. Wang X. Q. Huang Z. G. Wang 《Philosophical Magazine Letters》2013,93(11):705-712
Ti–Al–Zr alloy has been oxidized at 360°C in alkaline steam at a pressure of 10.3?±?0.7?MPa. Cross-sectional transmission electron microscopy (TEM) observations indicated that the oxide scale of Ti–Al–Zr alloy was composed of outer and inner subscales, in which the outer layer consists of anatase-TiO2 and the inner layer a mixture of TiO and Ti2O. The thickness of the Ti2O, TiO and anatase-TiO2 were approximately 50, 100 and 400?nm, respectively. These results were confirmed by X-ray energy dispersive spectrometry (EDS) measurements. The enhanced corrosion of titanium alloys in LiOH solution is attributed to a high hexagonal Ti2O to tetragonal TiO2 phase transformation rate induced by the substitution of Li+ for Ti4+ in the oxide layer. 相似文献
102.
器官供需严重不平衡导致了人体器官买卖的产生,器官买卖对供体和受体均存在潜在风险,对社会危险性也不容忽视.分析了器官买卖链条中供体、受体和中介各自的角色和地位,并提出了立法推动尸体器官捐献、加强医院和医务人员承担的法律责任、打击买卖中介和加强网络监管等建议. 相似文献
103.
对于女性盆腔脏器脱垂的手术治疗,传统的手术方式包括阴道封闭术、曼氏手术和阴式全子宫切除术.阴道封闭术操作相对简单,适用于无性生活要求的、合并症较多的年老体弱者,但术后可能存在新发压力性尿失禁,并且导致性功能障碍,术中是否切除子宫尚有争议.曼氏手术保留子宫、操作简单,但术后脱垂复发及妊娠后宫颈机能不全问题仍有待研究.阴式全子宫切除术对于POP-Q评分II期及以内的脱垂患者,治疗效果最佳,期别高的患者术后复发仍可使用保守或再次手术治疗补救,本手术方式术后较少出现性交痛.总而言之,选择适当的适应证并积极与患者沟通后,女性盆腔脏器脱垂的传统手术治疗仍为不错的治疗方式. 相似文献
104.
Piracy is the greatest threat facing the global music industry today. This study explores the effects of artist adoration and the perceived risk of being caught on the attitude and intention to engage in pirating a digital song among college students. The moderating effect of cultural environment factor is also examined. Experiments using between-group factorial designs were conducted in the United States and Taiwan. The results show that perceived risk of getting caught and cultural environment are important factors that can significantly affect the attitude and intention toward downloading unauthorized music. In addition, a two-way (Perceived Risk × Culture) and a three-way interaction in the model are also observed. 相似文献
105.
Junwei Huang Lehua Cheng Jing Zhu 《The International journal for the psychology of religion》2013,23(1):29-41
Jesse Bering (2002) investigated how American university students in an interview task conceived of dead persons' mentality immediately after death. He found that different categories of mental states or capacities were conceived differently: psychobiological and perceptual states ceased, whereas emotional, desire, and epistemic states continued. Our Study 1 was a replication of Bering's experiment in a different cultural setting, in which the subjects were Chinese undergraduate students. A similar pattern of results was found. In Study 2, instead of being asked about a dead person's various mental states immediately following the death, participants were asked to judge a dead person's mental states after the person had been dead for 2 days. The overall pattern of participants' responses was not affected by this manipulation, but they did show an increase in attributions of certain mental states to dead agnostics. In addition, a more refined breakdown of responses revealed that individuals tended to judge that, upon death, visual and auditory perception continued, whereas olfactory and gustatory sensation ceased. 相似文献
106.
This study investigated how frequency demand and motion feedback influenced composite ocular movements and eye-hand synergy during manual tracking. Fourteen volunteers conducted slow and fast force-tracking in which targets were displayed in either line-mode or wave-mode to guide manual tracking with target movement of direct position or velocity nature. The results showed that eye-hand synergy was a selective response of spatiotemporal coupling conditional on target rate and feedback mode. Slow and line-mode tracking exhibited stronger eye-hand coupling than fast and wave-mode tracking. Both eye movement and manual action led the target signal during fast-tracking, while the latency of ocular navigation during slow-tracking depended on the feedback mode. Slow-tracking resulted in more saccadic responses and larger pursuit gains than fast-tracking. Line-mode tracking led to larger pursuit gains but fewer and shorter gaze fixations than wave-mode tracking. During slow-tracking, incidences of saccade and gaze fixation fluctuated across a target cycle, peaking at velocity maximum and the maximal curvature of target displacement, respectively. For line-mode tracking, the incidence of smooth pursuit was phase-dependent, peaking at velocity maximum as well. Manual behavior of slow or line-mode tracking was better predicted by composite eye movements than that of fast or wave-mode tracking. In conclusion, manual tracking relied on versatile visual strategies to perceive target movements of different kinematic properties, which suggested a flexible coordinative control for the ocular and manual sensorimotor systems. 相似文献
107.
This study examines the dynamic regulation process responding to an external stimulus. The damped oscillator model has been used to describe this process. However, the model does not allow a nonzero steady state, even though the oscillations may continue and do not necessarily damp toward zero. This study introduces the driven damped oscillator model which has an additional parameter to identify different patterns of the steady state. Three methods, generalized local linear approximation, continuous time structural equation modeling, and analytic solutions of differential equations are provided to estimate model parameters. A simulation study indicates that parameters in the driven damped oscillator model are well recovered. The model is then illustrated using a data set on the daily reports of sales after a sale promotion. Potential applications and possible expansions of this model are also discussed. 相似文献
108.
This study investigated the sensitivity of common fit indices (i.e., RMSEA, CFI, TLI, SRMR-W, and SRMR-B) for detecting misspecified multilevel SEMs. The design factors for the Monte Carlo study were numbers of groups in between-group models (100, 150, and 300), group size (10, 20, 30, and 60), intra-class correlation (low, medium, and high), and the types of model misspecification (Simple and Complex). The simulation results showed that CFI, TLI, and RMSEA could only identify the misspecification in the within-group model. Additionally, CFI, TLI, and RMSEA were more sensitive to misspecification in pattern coefficients while SRMR-W was more sensitive to misspecification in factor covariance. Moreover, TLI outperformed both CFI and RMSEA in terms of the hit rates of detecting the within-group misspecification in factor covariance. On the other hand, SRMR-B was the only fit index sensitive to misspecification in the between-group model and more sensitive to misspecification in factor covariance than misspecification in pattern coefficients. Finally, we found that the influence of ICC on the performance of targeted fit indices was trivial. 相似文献
109.
Ming Huang Xinye Yang Jichun Xiong Jiarong Li Sen Yang 《Philosophical Magazine Letters》2013,93(9):392-399
ABSTRACTThe interaction between interfacial dislocations and γ/γ′ interface is critical to the high temperature creep properties of single crystal superalloys. However, only a few studies have paid attention to the detailed structure such as local interfacial morphologies and the elemental distribution around interfacial dislocations. In this paper, the interfacial protrusions and related dislocations in a single crystal superalloy after creep at high temperature – low stress have been investigated in detail. It is found that the morphology and size of the interfacial protrusions remain almost the same during the early and middle stages of high temperature creep, which indicates a local equilibrium at the interfacial protrusions. Steps at different height are formed at the γ/γ′ interface at the initial stage of high temperature creep since dislocations could move along the γ/γ′ interface, which indicates that dislocation motion at different creep stage may affect the morphology of γ/γ′ interface. 相似文献
110.
Tsatomu Mashimo Masao Ono Takahiro Kinoshita Xinsheng Huang Toyotaka Osakabe Hiroshi Yasuoka 《Philosophical Magazine Letters》2013,93(11):687-690
It was found that an atomic-scale graded structure was formed, and a phase change occurred, in an In–Pb alloy by the sedimentation of substitutional solute atoms under an ultrastrong gravitational field (820?000?g (maximum); 150°C; 100?h). Continuous gradients in the concentration of Pb (from about 6 to 45?at.%) and In (from about 94 to 55?at.%) and resulting changes in the lattice constant were observed. Fcc (Pb-rich) and tetragonal (In-rich) phases appeared in the strong- and weak-gravity regions respectively from a single starting fct α phase. It is suggested that sedimentation of substitutional atoms can be used to control the compositions and structure of bulk materials and also thin films or layer interfaces. 相似文献