胀大

Venomous Asiatic and African elapid snakes that can ''.

亚洲和非洲有毒的眼镜蛇，其颈布皮肤能胀大如帽状。

Forming part of the paragraph L / D ≥ 1 and for forming slip paragraph 1 / 2 of the gas-assisted die, as the entrance to the storage of elastic strain energy in the gas-assisted paragraph has been fully released from the mold after the swollen out of the mouth than with the Import model geometry has nothing to do

对于成型段部位L/D≥1且滑移段为成型段1/2的气辅口模，由于入口储存的弹性应变能在气辅段已经完全释放，离模后挤出胀大比与口模入口几何结构无关。

Theoretical and experimental analyses show that different entrance angle of die is responsible for the degree of...

理论和实验研究结果进一步表明不同圆锥口模入口角对实验材料表现出有不同的挤出胀大值

Polymer melt ; extrusion swell ; conical short die ; die entrance angle

聚合物熔体；挤出胀大；圆锥短口模；口模入口角

In this thesis, the author has investigated the effects of two methods of updating the swellfree surface and some characteristic parameters in the finite element meshes on the extrudateswell for Newtonian fluid using variance analyses.

本文首先用方差分析方法考察了两种挤出胀大表面形成方法和有限元网格中的几个特征参数对牛顿流体挤出胀大的影响。

The gel dynamics experiments showed that the gel formation law was similar with the other polymer systems, which wasrelated with dense surface under the soft coagulating condition and the thickening gel; the square of gel thickness was linear with coagulation time. The qualitative analysis of the surface puckers of fibers spun from wet spinning and dry-jet wet spinning was made. The positions where the die swell appeared were not the same and the die swell appeared at the air gap where the fiber would markedly been elongated and vary little in the coagulant, thus the surface of fiber spun from dry-jet wet spinning was more smooth. The radial component concentration gradient was responsible for the radial structure of PAN fiber spun from dry-jet wet spinning. The thicker surface with microvoid structure of

对湿纺和干湿纺进行比较表层沟槽的产生进行定性分析，原因在于孔口胀大区域出现在不同位置，在干湿纺中，溶液的孔口胀大出现在空气层，并在该区完成大部分形变，进入凝固浴后形变很小，纤维表面较为光滑；干湿纺PAN纤维径向结构存在差异，这与丝条内组分由于双扩散进行导致径向上存在浓度差异直接相关；凝固强度较大的体系，可以获得厚度较大且孔结构尺寸较小的皮层；含较少缠结的PAN原液在纤维成形后截面很圆整，但原液缠结浓度增大时成形后圆整度下降；PAN纤维成形是一个远离平衡的过程，凝固作用缓和的体系可以使成形过程靠近平衡，可获得更大尺寸的孔洞结构；原液中少量的非溶剂添加剂显著改变纤维径向结构，可获得孔洞尺寸更小和更为均一的径向结构，这与径向浓度差异的减小、分相时间的集中相关；PAN原液的成形纤维表面依赖于凝固强度；由AFM对相近凝固条件下成形的PAN膜进下

The samples were smeared on slides and stained with Giemsas stain. The stained smears were observed microscopically and photographed. It showed that except typical trophozoites in binary fission. the following trophozoites of abnormal morphs were also observed. for instance abnormal trophozoites with binary fission; enlarged trophozoites with round and irregular shaped eosinophilic bodies in the cell plasma; enlarged cells containing round and irregular shaped eosinophilic bodies and flagella; enlarged cells which contain 6 or 8 nuclear-like bodies and flagella, 3 or 4 embryonic forms of daughter trophozoite in one mother trophozoite; 4 trophozoite embryonic forms with fused plasma 3 trophozoites with fused plasma;4 trophozoites with fused plasma; a pair of trophozoite with binary fission fused with another trophozoite;2 pairs of trophozoite with binary fission fused each other; a trophozoite with 1 nuclear only.

结果 除观察到典型的营二分裂法繁殖的贾第虫滋养体外，还可见到多种形态异常的虫体，包括；虫体呈非典型二分裂；滋养体胀大，胞质中有团块状和不规则形状的嗜酸性物质；在胀大的贾第虫细胞内含有团块状和不规则形状的嗜酸性物质以及鞭毛；在胀大的贾第虫细胞内含有6或8个核状物以及鞭毛；在一个母体细胞中含有3或4个子体细胞的雏形；胞质互相融合的4个滋养体的雏形；胞质互相触合的3个滋养体，胞质互相融合的4个滋养体；1对营二分裂的滋养体与另一个滋养休互相融合；2对营二分裂的滋养体互相融合；仅有1个细胞核的滋养体。

The simulation results show that the die swell rate of height direction is greater than that of width direction. Due to the difference of material characteristic of the two polymers, the end section shape of coextrusion is dissymmetric drum. The coextrusion interface would be change during the extrusion swell process.

有限元模拟结果显示：聚合物在离开方形口模后，熔体高度方向的挤出胀大率明显大于宽度方向的胀大率，且两种熔体的挤出胀大率不同，熔体术端截面形状为不对称的鼓形；在挤出胀大段，共挤出界面的形状和位置会发生变化。

In this dissertation the"Penalty"finite element method was employed to compute the velocity of the three-dimensional flow of power-law fluid in a profile die. In order to decrease the needed computer memory and raise the stability of numerical simulation, a set of decoupled methods such as PFEM, pseudo-body force method and transformation of momentum equation to the elliptic equation was developed to establish the general finite element equations to compute the distributions of velocity and viscoelastic stress of the three-dimensional viscoelastic flow of the Phan ThienTanner fluid in a profile die. During numerical simulation of the extrudate swell of the PTT fluid, the flow in the die and out of the die was analyzed separately, which demands less computer memory.

本文建立了求解挤出口模内幂律流体流动速度场的通用三维罚有限元模型；对于非线性粘弹性的Phan Thien-Tanner流体，为了降低模拟计算对计算机硬件的要求，并使模拟计算更加稳定，采用了一种去耦算法，包括罚有限元方法、拟体力方法和动量方程的椭圆类方程转化方法，并建立了求解速度场和粘弹性应力场的总体有限元方程；对于PTT流体的挤出胀大问题，提出了挤出胀大熔体口模内外分离模拟法，这样可以显著降低数值模拟对计算机硬件的要求。

In this dissertation the"Penalty"finite element method was employed to compute the velocity of the three-dimensional flow of power-law fluid in a profile die. In order to decrease the needed computer memory and raise the stability of numerical simulation, a set of decoupled methods such as PFEM, pseudo-body force method and transformation of momentum equation to the elliptic equation was developed to establish the general finite element equations to compute the distributions of velocity and viscoelastic stress of the three-dimensional viscoelastic flow of the Phan ThienTanner fluid in a profile die. During numerical simulation of the extrudate swell of the PTT fluid, the flow in the die and out of the die was analyzed separately, which demands less computer memory. The key techniques used in numerical simulation of the three-dimensional extrusion from dies such as decision of boundary conditions, creation of initial velocity field, selection of penalty factor, high Weissenberg number problem , regeneration of the free surface were studied in detail.

中文题名聚合物异型材口模挤出三维流动研究副题名外文题名 Study on three-dimensional flow of polymer melts during the process of profile extrusion from dies 论文作者涂志刚导师柳和生包忠诩教授学科专业材料加工工程研究领域\研究方向学位级别博士学位授予单位南昌大学学位授予日期2001 论文页码总数148页关键词挤出成型聚合物材料挤出口模聚合物异型材馆藏号BSLW /2003 /TQ320 /9 本文建立了求解挤出口模内幂律流体流动速度场的通用三维罚有限元模型；对于非线性粘弹性的Phan Thien-Tanner流体，为了降低模拟计算对计算机硬件的要求，并使模拟计算更加稳定，采用了一种去耦算法，包括罚有限元方法、拟体力方法和动量方程的椭圆类方程转化方法，并建立了求解速度场和粘弹性应力场的总体有限元方程；对于PTT流体的挤出胀大问题，提出了挤出胀大熔体口模内外分离模拟法，这样可以显著降低数值模拟对计算机硬件的要求。

For a big chunk of credit-card losses; the number of filings (and thus charge-off rates) would be rising again, whether

年美国个人破产法的一个改动使得破产登记急速下降，而后引起了信用卡大规模的亏损。

Eph. 4:23 And that you be renewed in the spirit of your mind

弗四23 而在你们心思的灵里得以更新