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51.
S. Nag Y. Zheng R.E.A. Williams A. Devaraj A. Boyne Y. Wang P.C. Collins G.B. Viswanathan J.S. Tiley B.C. Muddle R. Banerjee H.L. Fraser 《Acta Materialia》2012,60(18):6247-6256
This paper presents experimental evidence of homogeneous precipitation of the α-phase within the β matrix of a titanium alloy, and then accounts for this phase transformation by a new, non-classical mechanism involving compositional fluctuations, based on the pseudo-spinodal concept [1]. This mechanism involves local compositional fluctuations of small amplitude which, when of a certain magnitude, can favor thermodynamically certain regions of the β matrix to transform congruently to the α-phase but with compositions far from equilibrium. Subsequently, as measured experimentally using the tomographical atom probe, continuous diffusional partitioning between the parent β- and product α-phases during isothermal annealing drives their compositions towards equilibrium. For a given alloy composition, the decomposition mechanism is strongly temperature dependent, which would be expected for homogeneous precipitation via the compositional fluctuation-mediated mechanism but not necessarily for one based on classical nucleation theory. The applicability of this mechanism to phase transformations in general is noted. 相似文献
52.
The effect of a partial horizontal partition plate of finite thickness, attached to the heated vertical wall of a differentially heated square cavity, has been studied numerically using the finite element method. The partition thickness is varied from 0.5% of the height of the cavity to 10%. The partition is considered to be located at the middle of the hot wall of a width equivalent to 20% of the cavity width. It is observed that as the partition thickness is reduced, heat transfer across the cavity decreases at first, until a critical thickness of the partition plate is reached. Beyond this value, heat transfer increases as the thickness of the partition is further reduced. Streamline maps are found to be notably sensitive to the partition thickness. The effect of conductivity of the partition material on heat transfer is also studied. Except for material with poor thermal properties, conductivity of the partition is observed to have a negligible effect on heat transfer. 相似文献
53.
[Correction Notice: An erratum for this article was reported in Vol 137(2) of Psychological Bulletin (see record 2011-03899-006). In Table 2, weighted population correlations and associated standard errors and confidence intervals are incorrectly reported. In Table 3, weighted population correlations and associated confidence intervals are incorrectly reported, as well as the Q statistic for trait forgiveness. Corrected data are presented. The authors note that substantive interpretations of the results are not affected by the corrections. The median absolute value correction for the weighted population correlations in both tables is r = .01.] Forgiveness has received widespread attention among psychologists from social, personality, clinical, developmental, and organizational perspectives alike. Despite great progress, the forgiveness literature has witnessed few attempts at empirical integration. Toward this end, we meta-analyze results from 175 studies and 26,006 participants to examine the correlates of interpersonal forgiveness (i.e., forgiveness of a single offender by a single victim). A tripartite forgiveness typology is proposed, encompassing victims' (a) cognitions, (b) affect, and (c) constraints following offense, with each consisting of situational and dispositional components. We tested hypotheses with respect to 22 distinct constructs, as correlates of forgiveness, that have been measured across different fields within psychology. We also evaluated key sample and study characteristics, including gender, age, time, and methodology as main effects and moderators. Results highlight the multifaceted nature of forgiveness. Variables with particularly notable effects include intent (r? = ?.49), state empathy (r? = .51), apology (r? = .42), and state anger (r? = ?.41). Consistent with previous theory, situational constructs are shown to account for greater variance in forgiveness than victim dispositions, although within-category differences are considerable. Sample and study characteristics yielded negligible effects on forgiveness, despite previous theorizing to the contrary: The effect of gender was nonsignificant (r? = .01), and the effect of age was negligible (r? = .06). Preliminary evidence suggests that methodology may exhibit some moderating effects. Scenario methodologies led to enhanced effects for cognitions; recall methodologies led to enhanced effects for affect. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
54.
Chaudhuri Sandeep K. Kleppinger Joshua W. Karadavut OmerFaruk Nag Ritwik Panta Rojina Agostinelli Forest Sheth Amit Roy Utpal N. James Ralph B. Mandal Krishna C. 《Journal of Materials Science: Materials in Electronics》2022,33(3):1452-1463
Journal of Materials Science: Materials in Electronics - In this article, we report the growth of Cd0.9Zn0.1Te0.97Se0.03 (CZTS) wide bandgap semiconductor single crystals for room temperature... 相似文献
55.
This paper deals with the study of heat transfer behaviour in the cyclone separator of a circulating fluidized bed (CFB) and how it is affected by relevant operating parameters. The experiments are conducted in a 140 mm diameter cyclone of a cold bed set‐up of 102 mm×102 mm bed cross‐section, 5.25 m height CFB. The cyclone separator is designed according to the high‐efficiency Lapple design and made to accommodate two identical heat transfer probes. From the experimental results, the heat transfer coefficient is found to increase with increase in solid circulation rate, as well as gas superficial velocity. The effect of bed inventory and heat flux on heat transfer coefficient has also been investigated. An empirical equation has been developed to predict the heat transfer coefficient in the cyclone separator based on dimensional analysis. The experimental results are compared with the predicted results and a good agreement has been observed. There is an optimal distance from the entry of the cyclone where the local heat transfer coefficient is maximum. The collection efficiency of the cyclone separator has been measured for all the operating conditions. Copyright © 2000 John Wiley & Sons, Ltd. 相似文献
56.
S Nag AA Abitbol LL Anderson JC Blasko A Flores LB Harrison BS Hilaris AA Martinez MP Mehta D Nori 《Canadian Metallurgical Quarterly》1993,27(5):1241-1244
PURPOSE: A large number of medical centers have recently instituted the use of High Dose-Rate Afterloading Brachytherapy (HDRAB). There is wide variation in treatment regimens, techniques, and dosimetry being used and there are no national standard protocols or guidelines for optimal therapy. METHODS AND MATERIALS: The Clinical Research Committee (CRC) of the American Endocurietherapy Society (AES) met to formulate consensus guidelines for HDRAB in cervical, endometrial, and endobronchial tumors. CONCLUSION: Each center is encouraged to follow a consistent treatment policy in a controlled fashion with complete documentation of treatment parameters and outcome including efficacy and morbidity. Until further clinical data becomes available, the linear quadratic model can be used as a guideline to formulate a new HDR regimen exercising caution when changing from a Low Dose Rate (LDR) to a HDRAB regimen. The treatments should be fractionated as much as practical to minimize long term morbidity. As more clinical data becomes available, the guidelines will mature and be updated by the Clinical Research Committee of the AES. 相似文献
57.
B. R. Nag 《Journal of Electronic Materials》1997,26(2):70-72
The melting point is found to vary linearly with the direct bandgap for groups of semiconductors with common anions. Implication
of this empirical result is discussed. The linear relation is used to choose between different reported values of melting
point for some compounds. 相似文献
58.
Pilot plant studies have shown that solid waste represents a valuable source of energy. Efforts have been made to scale up the data to process 1000 tons/day of Calcutta municipal waste. The advantage of this process is that product fuel oil is a saleable commodity, thus becoming an effective waste disposal technique and source for non-conventional energy. 相似文献
59.
In the present paper thermodynamic analyses, i.e. both energy and exergy analyses have been conducted for a coal based combined cycle power plant, which consists of pressurized circulating fluidized bed (PCFB) partial gasification unit and an atmospheric circulating fluidized bed (ACFB) char combustion unit. Dual pressure steam cycle is considered for the bottoming cycle to reduce irreversibilities during heat transfer from gas to water/steam. The effect of operating variables such as pressure ratio, gas turbine inlet temperature on the performance of combined cycle power plant has been investigated. The pressure ratio and maximum temperature (gas turbine inlet temperature) are identified as the dominant parameters having impact on the combined cycle plant performance. The work output of the topping cycle is found to increase with pressure ratio, while for the bottoming cycle it decreases. However, for the same gas turbine inlet temperature the overall work output of the combined cycle plant increases up to a certain pressure ratio, and thereafter not much increase is observed. The entropy generation, the irreversibilities in each component of the combined cycle and the exergy destruction/losses are also estimated. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
60.
S Nag 《Canadian Metallurgical Quarterly》1995,90(5):454-460
The role of the cytoskeletal elements, microfilaments and microtubules in cerebral endothelial permeability to protein during steady states was investigated by studies of cerebrovascular permeability to horseradish peroxidase (HRP) in rats pretreated with cytochalasin B or colchicine, agents known to disrupt microfilaments and microtubules, respectively. In addition, the effect of colchicine pretreatment on the alterations in cerebrovascular permeability that occur in acute hypertension were studied. Rats infused with cytochalasin B showed increased cerebrovascular permeability to HRP in multifocal areas of the ipsilateral hemisphere. Most of the permeable vessels were arterioles; however, capillaries and venules also showed increased permeability. Ultrastructural studies of permeable vessels showed HRP in all layers of vessel walls and in endothelial and smooth muscle cell pinocytotic vesicles, which were increased in number. Although segments of interendothelial spaces were labeled by tracer, continuous labeling of interendothelial spaces from the luminal to the abluminal end was not seen and tight junctions were not disrupted. Normotensive rats pretreated with colchicine showed no alteration in cerebrovascular permeability to HRP. Colchicine pretreatment attenuated the permeability alterations that were observed in acutely hypertensive rats. This study demonstrates that integrity of endothelial actin filaments is important for maintenance of the blood-brain barrier to protein during steady states since increased permeability occurred in the presence of an actin disrupting agent. The microtubular network had no demonstrable role during steady states; however, disruption of the microtubular network had a protective effect and prevented the development of alterations in permeability to protein in acute hypertension. 相似文献