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Journal of Rare Earths 2014年第1期32卷 29-36页

作者： Choon-w.Nahm Semiconductor Ceramics Laboratory Department of Electrical Engineering Dongeui University

The effect of sintering temperature on microstructure, electrical properties, and pulse aging behavior of （V2O5-Mn3O4-Er2O3）-doped zinc oxide varistor ceramics was systematically studied. when the sintering temperature increased, the average grain size increased from 6.1 to 8.7μm and the sintered density decreased from 5.52 to 5.43 g/cm3. The breakdown field decreased from 3856 to 922 V/cm with an increase in the sintering temperature up to 900 °C, whereas a further increase to 2352 V/cm at 925 °C. The nonlinear coefficient increased pronouncedly from 4.6 to 30.0 with an increase in the sintering temperature. The varistor ceramics sintered at 850 °C exhibited the best clamping characteristics, with the clamp voltage ratio of the range of 2.22-2.88 for pulse current of 1-25 A. The varistor ceramics sintered at 925 °C exhibited the strongest stability, with %ΔE1 mA/cm2=-8.8% after applying the multi-pulse current of 25 A.

关键词： ceramics sintering electrical properties pulse aging behavior varistors rare earths

Hepatocellular carcinoma recurrence after liver transplant:An Australian single-centre study

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world Journal of Transplantation 2025年第1期15卷 105-114页

作者： Matthew G Garas Luis Calzadilla-Bertot Briohny w Smith Luc Delriviere Byron Jaques Lingjun Mou Leon A Adams Gerry C MacQuillan George Garas Gary P Jeffrey Michael C wallace Medical School University of Western AustraliaNedlands 6009Western AustraliaAustralia Department of Hepatology Sir Charles Gairdner HospitalNedlands 6009Western AustraliaAustralia Department of Surgery Sir Charles Gairdner HospitalNedlands 6009Western AustraliaAustralia

BACKGROUND Hepatocellular carcinoma(HCC)is a leading cause of cancer-related deaths *** transplantation(LT)offers the most effective *** recurrence is the strongest risk factor that decreases post-LT survival in patients transplanted for *** rate of HCC recurrence is generally reported as 8%-20%in the *** predictors of HCC have already been researched,however,to our knowledge there are no published studies on this topic using Australian *** To determine the rate and identify predictors of HCC recurrence in a contemporary western Australian LT *** we performed a retrospective cohort study of all liver transplants in patients with HCC at Sir Charles Gairdner Hospital between 2006 and *** was collected from various health record databases and included recipient demographics,serum biochemistry,radiology,operation notes,explant histopathology and details of *** survival of HCC patients post-LT,stratified for recurrence,was calculated by Kaplan Meier *** and multivariate Cox regression was used to determine predictors of HCC recurrence *** Between 1/1/2006 and 12/31/2021,119 patients were transplanted with HCC.8.4%of subjects developed recurrent HCC after LT with median follow-up time of 5.4 *** median time to recurrence was 2.9 years±0.75 *** comparing baseline characteristics,a greater proportion of subjects with recurrence had common characteristics on explant histopathology,including>3 viable nodules(P=0.001),vascular invasion(P=0.003)and poorly differentiated HCC(P=0.03).Unadjusted survival curves showed lower 1-year,3-year,5-year and 10-year survival rates in subjects with HCC recurrence compared to those without HCC recurrence(90%vs 92%,70%vs 88%,42%vs 80%,14%vs 76%,respectively;log rank Pwas low at 8.4%in this contemporary Australian cohort,however it significantly impacted post-LT *** studies are requir

关键词： Liver cancer Recurrence Liver transplantation Hepatocellular carcinoma Predictors Post-transplant survival Australian data

Inducible competitors and adaptive diversification

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Current Zoology 2013年第4期59卷 537-552页

作者： Beren w. ROBINSON David w. PFENNIG Department of Integrative Biology University of Guelph Guelph Ontario N 1G 2W 1 Canada Department of Biology University of North Carolina Chapel Hill NC 27599 USA

Identifying the causes of diversification is central to evolutionary biology. The ecological theory of adaptive diversi- fication holds that the evolution of phenotypic differences between populations and species--and the formation of new spe- cies-stems from divergent natural selection, often arising from competitive interactions. Although increasing evidence suggests that phenotypic plasticity can facilitate this process, it is not generally appreciated that competitively mediated selection often also provides ideal conditions for phenotypic plasticity to evolve in the first place. Here, we discuss how competition plays at least two key roles in adaptive diversification depending on its pattern. First, heterogenous competition initially generates heterogeneity in resource use that favors adaptive plasticity in the form of ＂inducible competitors＂. Second, once such competitively induced plas- ticity evolves, its capacity to rapidly generate phenotypic variation and expose phenotypes to alternate selective regimes allows populations to respond readily to selection favoring diversification, as may occur when competition generates steady diversifying selection that permanently drives the evolutionary divergence of populations that use different resources. Thus, competition plays two important roles in adaptive diversification---one well-known and the other only now emerging--mediated through its effect on the evolution ofphenotypic plasticity

关键词： Phenotypic plasticity Competition Adaptive radiation Character displacement Genetic assimilation Resourcepolymorphism

Convergence, stability and robustness analysis of the OFEX controller for high-speed networks

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Control Theory and Technology 2016年第2期14卷 122-139页

作者： Jungang LIU Oliver w. w. YANG School of Electrical Engineering and Computer Science University of Ottawa Ottawa KI N 6N5 Canada

The OFEX （Optimal and Fully EXplicit） rate controller is able to provide not only the optimal bandwidth allocation but also the fully explicit congestion signal to sources. It exercises link-wise proportional fairness and network-wise max-min fairness, which enables the controller to feed the congestion signal back from the most congested link, instead of using the network- wise proportional fairness which feeds back the congestion signal summed along a flow path. As a result, the OFEX controller overcomes the drawbacks of the relatively explicit controllers that 1） bias the multi-bottlenecked users in terms of their source sending rate and convergence speed, 2） are not adaptable to varying link bandwidth and 3） can potentially incur large queue size upon congestion. In this paper, we first prove that the OFEX controller can converge to its equilibrium at least as fast as a geometric series in a link. Then we analyze the system stability with time delay in a single bottleneck network and show that the OFEX controller can achieve local stability under certain conditions. Besides, the robustness analysis of the OFEX controller shows how the dynamics of link bandwidth may affect the revenue of a link. Finally, with the OPNET modeler, we evaluate the performances of the OFEX controller and verify its effectiveness.

关键词： Fully explicit convergence stability time delay robustness performance evaluation

GROwTH KINETICS OF SINGLE INCLUSION PARTICLE IN MOLTEN MELTS

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Acta Metallurgica Sinica(English Letters) 2007年第2期20卷 129-138页

作者： B.w. Zhang B.w. Li Department of Materials and Metallurgy Inner Mongolia University of Science and Technology Baotou 014010 China

On the basis of the single-particle framework, a new theory on inclusion growth in metallurgical melts is developed to study the kinetics of inclusion growth on account of reaction and collision. The studies show that the early growth of inclusion depends on reaction growth and Brawnian motion collision, and where the former is decisive, the late growth depends on turbulence collision and Stokes＇ collision, and where the former is dominant; collision growth is very quick during the smelting process, lessened in the refining process, but nearly negligible in the continuous casting process.

关键词： inclusion growth reaction collision kinetics

Effect of compressibility on the hypervelocity penetration

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Acta Mechanica Sinica 2018年第1期34卷 82-98页

作者： w.J.Song X.w.Chen P.Chen Department of Mechanics and Engineering Science College of Engineering Peking University Advanced Research Institute for Multidisciplinary Science Beijing Institute of Technology The State Key Lab of Explosion Science and Technology Beijing Institute of Technology Centre for Applied Physics and Technology (CAPT) Peking University

we further consider the effect of rod strength by employing the compressible penetration model to study the effect of compressibility on hypervelocity ***, we define different instances of penetration efficiency in various modified models and compare these penetration efficiencies to identify the effects of different factors in the compressible model. To systematically discuss the effect of compressibility in different metallic rod-target combinations, we construct three cases, i.e., the penetrations by the more compressible rod into the less compressible target, rod into the analogously compressible target, and the less compressible rod into the more compressible target. The effects of volumetric strain, internal energy, and strength on the penetration efficiency are analyzed simultaneously. It indicates that the compressibility of the rod and target increases the pressure at the rod/target interface. The more compressible rod/target has larger volumetric strain and higher internal energy. Both the larger volumetric strain and higher strength enhance the penetration or anti-penetration ability. On the other hand, the higher internal energy weakens the penetration or anti-penetration ability. The two trends conflict, but the volumetric strain dominates in the variation of the penetration efficiency, which would not approach the hydrodynamic limit if the rod and target are not analogously compressible. However, if the compressibility of the rod and target is analogous, it has little effect on the penetration efficiency.

关键词： Compressibility Hypervelocity penetration Equation of state(EOS) Shockwave Bernoulli equation

Glass-forming Ability and Corrosion Resistance of Zr—Cu—Al—Co Bulk Metallic Glass

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Journal of Materials Science & Technology 2016年第4期32卷 349-354页

作者： w.Zhou w.P.weng J.X.Hou Shagang School of Iron and Steel Soochow University

Investigations were carried out to examine the effects of Co addition on the glass-forming ability （GFA） and corrosion resistance of Zr46Cu46AI8 bulk metallic glass in chloride-containing solution. It is found that the GFA of （Zr46Cu46Al8）100-xCox （x = 0, 1, 2, and 4 at.%） alloys reduces with the increase in Co content and correlates well with the parameters, such as the supercooled liquid region width ATx, the reduced glass transition temperature Trg and γ. The corrosion resistance is however found to be enhanced with the in- crease in Co concentration. The addition of Co causes the enrichment of Zr and Al, but depletes Cu in the surface films, which effectively enhances the corrosion potential and lowers the corrosion current density.

关键词： Bulk metallic glassCo-additionGlass-forming abilityCorrosion resistance

New Development of Acid Regeneration in Steel Pickling Plants

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Journal of Iron and Steel Research International 2008年第4期15卷 1-6页

作者： w F Kladnig ICC Chemical Consulting Vienna A-1193 Austria

For acid pickling heat treated mild steel and steel products, up to the middle of the last century, sulfuric acid was primarily in use, which has been replaced stepwise by hydrochloric acid since the sixties. During this time, the pickling of high alloyed steel with hydrofluoric acid or mixtures for hydrofluoric acid together with nitric acid has also been applied on industrial scale. The technologies used by several plant contractors hereby show considerable differences in their engineering. The study provides a survey of the progress in the state of art of regeneration technology as well as the use of different *** media in the form of a review on existing technologies as well as improvements done within the recent years in the area.

关键词： pickling mild steel high alloyed steel acid recycling technology global emission standard treatment of stack gas

Hormone naive prostate cancer： predicting and maximizing response intervals

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Asian Journal of Andrology 2015年第6期17卷 929-935,I0007,I0008页

作者： Judd w Moul Division of Urology Department of Urology Duke Cancer Institute Duke South Duke University Medical Center Durham NC 27710 USA.

Hormone naive advanced prostate cancer is subdivided into two disease states： biochemical recurrence and traditional M 1 （metastatic） prostate cancer and characterized by no prior hormonal therapy or androgen deprivation therapy （ADT）. In biochemical recurrence/ prostate-specific antigen （PSA） recurrence, men should be risk-stratified based on their PSA doubling time, the Gleason score and the timing of the recurrence. In general, only men who are at high risk should be considered for early/immediate ADT although this is best done using shared decision with the patient. The type of ADT to be used in biochemical recurrence ranging from oral-only peripheral blockade （peripheral androgen deprivation） to complete hormonal therapy （combined androgen blockade [CAB]） remains in debate owing to lack of randomized controlled trials （RCT）. However, there is good RCT support for use of intermittent hormonal therapy （IHT）. There is also limited research on biomarker response （PSA and testosterone decline） to predict prognosis. On the other hand, in the setting of M1 hormone naive prostate cancer, there are many more RCT＇s to inform our decisions. CAB and gonadotrophin-releasing hormone antagonists perhaps provide a slight efficacy advantage while IHT may be slightly inferior with minimal M1 disease. The PSA nadir at 7 months after starting ADT is a powerful prognostic tool for M1 patients. There is growing recognition that serum testosterone （T） control while on ADT is linked to the development of castrate-resistant prostate cancer. Especially for a M 1 patient, maintaining a serum T below 20-30 ng d1-1 prolongs the response to ADT. Novel oral agents （abiraterone and enzalutamide） may soon find use in hormone naive disease and may alter the treatment landscape. Despite over 75 years of experience with ADT, many questions remain, and the field continues to evolve.

关键词： androgen deprivation therapy cancer gonadotrophin-releasing hormone antagonists hormonal therapy luteinizing hormone-releasing hormone agonists prostate prostate-specific antigen testosterone

RESEARCH AND DEVELOPMENT OF NEw SUPERALLOY REMELTING PROCES

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Acta Metallurgica Sinica(English Letters) 2005年第1期18卷 81-90页

作者： w.Xie BaosteelGroupShanghaiNo.5SteelCo. Ltd.Shanghai200940China

Shanghai No.5 Steel Co., Ltd. has recently introduced a set of 5-ton protective atmosphere elec-troslag remelting furnace and a set of 10-ton helium-cooling vacuum arc remelting furnace, both of them are the first one of its kind in China. with these equipment, remelting processes about alloy GH4169, CH2132 and GH738 were researched, the process of producing alloy GH4169 by VIM+VAR+ESR triplex-process was developed, and their effects were discussed.

关键词： superalloy argon shield ESR helium cooling VAR VIM+VAR+ESR