稀土元素对Ni-Cr-Al合金高温氧化影响机理的研究

采用第一性原理赝势平面波方法,通过Materials Studio软件中的Castep模块,建立Al2O3晶胞,稀土元素Y的加入有助于控制Al2O3或Cr2O3的生长速度,减少氧化薄膜和基体间形成空洞,从而提高氧化薄膜的粘附性.稀土元素La的加入与S形成化合物,消除S对基体产生的不良反应,改善了氧化薄膜的粘附性.     

“不是N的N”格式研究

现代汉语语法中"不是N的N"是一种特殊的构式,但已有的研究大多是从单一的角度分析变量的语义或者是构式义,尚未对其进行多角度的分析。尝试运用认知语言学中的构式理论,采用描写和解释相结合的方法,对这个结构进行多角度分析,旨在深化对汉语中这种新型表达式的认识。     

扎鲁特盆地的大地电磁电阻率结构成像初步结果（英文）

为揭露扎鲁特盆地构造格架和识别二叠纪林西组地层分布特征,笔者在扎鲁特盆地进行重力、磁力、大地电磁综合地球物理调查。在2012年,采集了5条北西向大地电磁剖面。经过数据处理、分析后,反演后电阻率断面揭露了断层带和林西组分布特征。扎鲁特盆地西部边界被确定。发现了两个低阻带,推测它们可能是与页岩气有关的泥岩。这些工作将为扎鲁特盆地页岩气潜力评价提供依据。     

中国致密油藏水平井注水吞吐技术进展与发展趋势

中国致密油藏多采用水平井体积压裂衰竭式开发,水平井产量递减快,一次采收率不足10%。因此,有效补充地层能量是致密油藏体积压裂水平井稳产的关键。注水吞吐是致密油藏水平井的一种有效注水补充能量方法,近年来针对该方法进行了大量的研究和实践。在介绍注水吞吐工艺的基础上,从渗吸采油微观机理以及压力对渗吸排油影响两个方面对注水吞吐机理的研究进展进行了概述,并系统总结了储层性质和工艺参数对注水吞吐采油效果的影响。为了提高注水吞吐的开发效果,目前主要形成了化学处理剂辅助注水吞吐技术、大排量注水强化注水吞吐技术和水平井同井缝间异步注采技术3种改善注水吞吐开发效果的技术。进一步通过总结注水吞吐油藏数值模拟和工艺参数优化的研究成果,分析矿场实践经验,提出了中国致密油藏注水吞吐技术未来发展趋势。     

玛湖凹陷与沙湾凹陷上乌尔禾组储集层差异及成因

通过薄片观察、扫描电镜分析、黏土矿物X射线衍射分析、阴极发光实验等,对准噶尔盆地玛湖凹陷和沙湾凹陷上二叠统上乌尔禾组成岩差异进行对比分析,明确了成岩产物类型和孔隙演化过程。压实作用、碳酸盐矿物胶结与沸石胶结是研究区储集层物性差异的主要控制因素,玛湖凹陷压实作用相对较弱,沙湾凹陷溶蚀作用更强。砂体成岩孔隙演化具有差异性,玛湖凹陷储集层以长石颗粒和凝灰岩岩屑溶孔为主,沙湾凹陷储集层以长石颗粒、凝灰岩岩屑以及浊沸石溶孔为主,2类储集层都少量发育原生孔隙。以上2个地区储集层的差异性主要是由成岩流体性质和岩石组分不同导致,其中,岩石组分是导致玛湖凹陷和沙湾凹陷砂砾岩储集层孔隙结构特征差异的主要原因。     

基岩型富氦气藏形成条件

氦气是一种广泛应用于军工、航天、医疗等高新技术产业的稀缺战略资源,但其在世界分布极其不均,中国是贫氦国家面临着严峻的氦气供给安全问题。在系统总结前人研究成果基础上,结合本次实验分析对比了世界上最成熟的氦气生产气田（美国潘汉德—胡果顿气田）与中国氦气生产潜力较大的东坪气田,探讨两者的成藏要素及富氦机理。结果发现：两者均是以天然气作为载体气的基岩型富氦气藏,储层物性好,均发育以膏岩为主的低渗致密的良好盖层。两者的差异性在于,前者花岗岩形成年代更为古老,尤其是碳酸盐岩地层中富含的花岗岩碎屑,其年龄集中在元古宙,平均比东坪气田花岗岩的形成年代早400 Ma;前者氦气运移模式偏向于单一的饱和地下水脱溶释放,而后者存在“过路”古老花岗岩储层的天然气“萃取”释放。两者对比之下,提出形成年代久远的高U、Th氦源岩、充足的载体气、良好的基岩风化壳储层与致密的盖层,和充足的地下水（边底水）作为媒介参与氦气运移,是形成基岩型富氦气藏的必要条件。     

A computational approach to characterize formation of a passivation layer in lithium metal anodes

Li metal anode is the “Holy Grail” material of advanced Lithium-ion-batteries (LIBs). However, it is plagued by uncontrollable dendrite growth resulting in poor cycling efficiency and short-circuiting of batteries. This has spurred a plethora of research to understand the underlying mechanism of dendrite formation. While experimental studies suggest that there are complex physical and chemical interactions between heterogeneous solid-electrolyte interphase (SEI) and dendrite growth, most of the studies do not reveal the mechanisms triggering these interactions. To deal with this knowledge gap, we propose a multiscale modeling framework which couples kinetic Monte Carlo and Molecular Dynamics simulations. Specifically, the model has been developed to account for (a) heterogeneous SEI, (b) dendrite-SEI interactions, and (c) effect of electrolyte on Li electrodeposition and potential dendrite formation. This allows the proposed computational model to be extended to various electrolytes and SEI species and generate results consistent with previous experimental studies.     

Non-coalescence and chain formation of droplets under an alternating current electric field

The dynamic behaviors of two droplets and droplet cluster under an alternating current (AC) electric field are investigated. Two droplets generally undergo transformation from complete coalescence to partial coalescence and finally to non-coalescence as the electric capillary number Ca_p increases. The critical electric capillary number Ca_pc for complete coalescence in the AC electric field remains unchanged and is twice as large as that in the direct current (DC) electric field when the frequency f ≥ 250 Hz. Charge transfer and reversal of electric field result in the reversal of the direction of electric force, which is the fundamental mechanism of non-coalescence of two droplets and chain formation in droplet cluster. The number of rebounds dramatically increases as f increases, promoting the stability of droplet chain. The droplet chains in the high-frequency AC electric field are longer and more stable than those in the low-frequency AC electric field.     

Defect formation and its effect on the thermodynamic properties of Pu2Zr2O7 pyrochlore: a first-principles study

In the past decades, pyrochlores, such as Gd₂Zr₂O₇, have demonstrated great potential to immobilize nuclear wastes such as Pu, which results in the production of Pu₂Zr₂O₇. Due to the high radioactivity of Pu, it is difficult to investigate the radiation response behavior of Pu₂Zr₂O₇ and its physical properties of the damaged state experimentally. Consequently, few related data have been reported in the literature thus far. In this study, first-principles calculations have been carried out to investigate the defect formation and its effect on the thermodynamic properties of Pu₂Zr₂O₇. It reveals that Pu_Zr antisite and O_8a interstitial defects are very easy to form in Pu₂Zr₂O₇. In particular, the O_8a interstitial defect can be formed spontaneously, while it is mechanically unstable. When vacancy, interstitial or antisite defects are formed in Pu₂Zr₂O₇, and the elastic moduli and Debye temperature are decreased. Besides, better ductility is resulted. As compared with other zirconate pyrochlores, such as Gd₂Zr₂O₇, the Pu₂Zr₂O₇ is suggested to be less resistant to radiation-induced amorphization. This study demonstrates that the created defects due to self-radiation from actinide decay have remarkable influences on the thermophysical properties of Pu₂Zr₂O₇.     

金属催化剂在聚合物降解成炭阻燃中的研究进展

介绍了抗熔滴阻燃聚合物的研究现状,综述了金属催化剂在催化聚合物降解成炭方面的应用,主要包括铁系、钼系、镍系、锌系化合物及部分稀土材料等作为催化剂在聚合物阻燃中催化成炭抗熔滴的研究现状,尤其重点阐述了铁系催化剂的主要作用。最后,对金属催化剂在聚酯抗熔滴中的应用进行了展望。