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目前水平井中气液两相流动携液临界流量的计算方法仅考虑了水平井段的携液情况而没有考虑直井段与斜井段对携液的影响,所以在直井段和斜井段中未完全携带出的残余流体还是会流到井底,从而在水平井中产生积液.本文对液滴在水平井中直井段,斜井段和水平段进行受力分析发现,在不同的井段液滴因为受力不同从而产生不同的形变,从而计算的携液临界流量也不相同。基于携液理论与气液两相流型理论,根据不同位置的受力情况分别推导了液滴处于直井段,斜井段和水平段时的携液临界流量公式.而水平井的携液临界流量应该为液滴从直井段,斜井段和水平段流过时携液临界流量的最大值。最后通过理论计算与实验结果验证了方法的正确性. 相似文献
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The synthesis of filled skutterudite compounds (Ce or Y)_y(Fe)_x(Co)_(4x)(Sb)_(12), through a solidstate reaction using chloride of Ce or Y,high purity powder of Co, Fe, and Sb as starting materials,was investigated. (Ce or Y)_y(Fe)_x(Co)_(4x)(Sb)_(12) (x=0--1.0, y=0--0.15) compounds were obtained at850--1 123 K. The results of Rietveld analysis demonstrate that (Ce or Y)_y(Fe)_x(Co)_(4x)(Sb)_12synthesized by a solid state reaction possesses a filled skutterudite structure. The filling fraction ofCe or Y obtained by Rietveld analysis agrees well with the composition obtained by chemicalanalysis. The lattice constant of (Ce)_y(Fe)_x(Co)_(4x)(Sb)_(12) increases with increasing substitution of Fe at Cosites, and with an increasing Ce filling fraction in the Sb-dodecahedron voids. The lattice thermalconductivity of (Ce or Y)_y(Fe)_x(Co)_(4x)(Sb)_(12) decreases significantly with an increasing Ce or Y fillingfraction in the voids and with substitution of Fe at Co sites. 相似文献
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Neutron powder diffraction and high-pressure synchrotron x-ray diffraction study of tantalum nitrides 下载免费PDF全文
Tantalum nitride(TaN) compact with a Vickers hardness of 26 GPa is prepared by a high-pressure and hightemperature(HPHT) method. The crystal structure and atom occupations of WC-type TaN have been investigated by neutron powder diffraction, and the compressibility of WC-type TaN has been investigated by using in-situ high-pressure synchrotron x-ray diffraction. The third-order Birch–Murnaghan equation of state fitted to the x-ray diffraction pressure–volume(P–V) sets of data, collected up to 41 GPa, yields ambient pressure isothermal bulk moduli of B'_0= 369(2) GPa with pressure derivatives of B 0= 4 for the WC-type TaN. The bulk modulus of WC-type TaN is not in good agreement with the previous result(B_0= 351 GPa), which is close to the recent theoretical calculation result(B_0= 378 GPa). An analysis of the experiment results shows that crystal structure of WC-type TaN can be viewed as alternate stacking of Ta and N layers along the c direction, and the covalent Ta–N bonds between Ta and N layers along the c axis in the crystal structure play an important role in the incompressibility and hardness of WC-type TaN. 相似文献
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以Ba为填充原子,在x=0—3.0,y=0—0.7的组成范围内,用多步固相反应法合成了单相BayFexCo4-xSb12化合物.用Rietveld方法对结构的精确化结果表明:合成的BayFexCo4-xSb12化合物具有填充式skutterudite结构,Ba的热振动参数(B)比Sb,Fe/Co的大,表明在Bay关键词:
填充式skutterudite化合物
固相反应 相似文献
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脂环族环氧树脂和螺环原碳酸酯的光引发正离子共聚合 总被引:2,自引:0,他引:2
<正> 无收缩单体-1,6,8,13-四氧螺[7,7]十三碳烷(SOC_7)和3,4-环氧基环己烷甲酸3',4'-环氧基环己烷甲酯(ERL-4221)的光引发正离子共聚合的研究结果表明,少量SOC_7加到ERL-4221体系中可抑制固化收缩没有明显降低热性能。ERL-4221对SOC_7的合适克分子比为4比1,由此得到T_g为203℃而聚合时体积收缩为4.4%的交联共聚物。 相似文献
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