有环的

Considered the inside and outside contour line was Archimedes spiral in the cold rolling, the forming law of rectangular cross sectional rings has been studied. And the more precise geometrical models and calculation models have been gained. The researches can be used as a theoretical and experimental foundation for the simulation of ring rolling process. At the same time, the results of theoretical analysis have a good agreement with the results of practical rolling production.

本文在考虑冷轧过程中环件的内外轮廓线均为阿基米德螺线的情况下，对矩形截面环件的轧制成形规律进行了研究，得到了较精确的几何模型和计算模型，为环件轧制过程的模拟提供了理论依据和实验依据，同时理论分析的结果与实际轧制生产过程中的结果有较好的吻合。

An artificial method of constrained coassembling process plan based on VRML model includes setting slide – rotary connection constraint; selecting artificial assembling body model; confirming constraint type of each component to its front or back end component in open or closed loop mechanism; calculating translation and rotary matrix of each component in moving course and its position parameter; generating time – order – path matrix and key frame as per time section; writing each key frame in reverse mode into interpolator of each component VRMC model; adding route in sequence between time and position sensors, position sensor and component form node for generating artificial picture.

本发明属于CAD协同产品设计技术领域，其特征在于：在网络环境下，设计者依托装在节点机上的三维VRML模型，以设计者与设计场景交互方式按照以下步骤实现有约束协同装配工艺规划：设定滑动转动联接约束；选定仿真装配体模型；确定开环或闭环机构中各零部件与它的前端和后端部件的约束类型；计算各零部件在运动过程中的平移和转动矩阵，再根据相应的约束计算运动过程中各零部件的位置参数；再据此生成零部件的时间-顺序-路径矩阵，按时间段形成关键帧；把各关键帧分别以逆序写入VRML各部件模型的插补器，依次在时间传感器和位置传感器之间、位置传感器和零部件造型节点间加入路由，生成仿真画面。

In the region upstream of vortex breakdown, the sectional streamlines emanating from the leading edge spiral inward to primary vortex and in the region downstream of the breakdown, on the other hand, the streamlines separating from the leading edge are not entrained into the vortex core in the instantaneous sense. Along the axis, the topology of the primary vortex alters several times starting from stable focus near the apex to unstable focus, and lasts back to stable focus near wake edge, the stable hmit cycle and unstable limit cycle are shown in this evolution.

发现在截面流线谱中，即使奇点的类型、数目及位置相同，奇点的连接方式也有可能不同；旋涡破裂点前，主涡由来自前缘的力线卷绕而成，主涡焦点与前缘半鞍点相连，旋涡破裂后，来自前缘的力线不再卷入主涡，主涡焦点与对称面上的鞍点相连：在流体由翼尖流向后缘的过程中，截面流线谱的拓扑结构发生了多次变化，主涡焦点相继由稳定状态转变为不稳定状态，最后又转化为稳定状态，并先后出现了稳定的极限环及不稳定极限环。

In fact, it was proved by Pastijn that the idempotent semirings for whichis a congruence form a proper subvariety of the variety of all id empotent semirings. Also the defining equations were given with three free var iables of this variety.

Pastijin证明了：是S上的同余的幂等元半环S的全体构成了幂等元半环簇的一个子簇，进一步还给出了这个子簇的含有3个变量的簇等式组，当时不知道这个子簇是否有两个变量的簇等式组。

In the leaves of Liriodendroideae, some of the abaxial epidermal cells are papillose and the vascular tissue of the main vein appears to be separated. However, papillose were not found and there are uniseriate, multicellular or unicellular hairs distributed on the epidermis, and the vascular tissue of the main vein appears to be continuous in the leaves of Magnolioideae. Furthermore, in the Magnolioideae, the structure of the leaves of plants in Manglietia are different from that of Magnolia.

结果表明：鹅掌楸亚科和木兰亚科在叶的结构上的主要区别是鹅掌楸亚科两种植物叶的部分下表皮细胞呈乳突状，且整个细胞外壁只形成一个乳突，而在木兰亚科的植物中有单列多细胞或单细胞的表皮毛，未发现乳突；鹅掌楸亚科植物的叶主脉维管组织环分隔呈束状，且其外包被的纤维也排列成束状，而木兰亚科的80种1亚种植物中，叶主脉维管组织连成轮状，其外面也由一圈连续的纤维环所包围。

Studying the marketing reengineering, this thesis concludes that:①marketing should go beyond a functional element to guide a company at a strategic level, it is the "soul" of a company,②vision analyzing, marketing architecture crafting and implementing, and stakeholders' interests balancing, are three integral parts of marketing for a company, and ③for its own survival and growth, Shuanghuan Auto needs a foresightful, holistic and sustainable marketing system to draw on.

通过对双环公司营销再造的研究，得出了如下结论：①营销不应被简单地看作是一个功能性概念，营销必须是一个战略经营的概念，它是公司的&灵魂&；②一个公司完整的营销活动必须涵盖企业愿景评估、营销体系设计与实施以及三个主要利益主体间的利益平衡这三个方面的内容；③双环公司要生存和发展，离不开具有前瞻性、系统性以及可持续性的营销系统的强有力支撑。

We assumed that after the PACl〓 was dosed into water, its hydrolysis-aggregation-precipitation process combined the most popular"core-link"or hexameric ring scheme and the more recent model of polynuclear formation involving a typical specie of tridecameric,〓. The integrate pattern can nicely explained the phenomena.

另外，研究表明，PACl中预制的Alb形态和铝盐在混凝过程投加入水后形成的Alb形态在稳定性上有很大的区别，这无疑是由于它们的化学结构上的不同造成的，推测铝盐在投加入水后，其水解聚合过程按&六元环&模式〓和&核环&模式〓结合进行，这种综合模式可以很好的解释实验中的现象。

The cut-off valve with pilot valve without hand wheel, stem and lift nut inside will guide block and guide slot Butterfly Valves to guide sleeve, the disc-shaped disc to disc type bowl shape, and holes in the bottom of the flap valve to open, the valve cover of the original valve stem hole to hole diversion, because of increased pressure ring, ring, and the valve flap to class mortar, so that the flow passage separated the upper chamber cavity, external cavity, cavity, in the cavity and The external cavity increases with draft tube and stainless steel manual ball valve, flap valve in the cover plate and the center of the end of installing the spring, the upper flap valve install compression seal of the pressure ring, outside the cavity of the wall to open a Drainage holes.

带先导球阀的截止阀无手轮、阀杆和内升降螺母，将导向块与导向槽改为导向套，将盘形阀瓣改为类钵体形阀瓣，并在底部开阀瓣孔，电动蝶阀将阀盖原阀杆孔改为导流孔，因增加压环、密封圈和将阀瓣改为类钵体，使上通流腔分隔为上腔、外腔、内腔，在上腔与外腔的外部加设有导流管与不锈钢手动球阀，在盖板与阀瓣底的中心部加设弹簧，阀瓣上部加设压紧密封圈的压环，在外腔的壁上开有放水孔。

Glycidyl benzoate,glycidyl propionate,glycidyl acetate were obtained respectly through a phase-transfer catalytic methodology using sodium benzoate, sodium propionate, sodium acetate and epichlorohydrin as raw materials, and pure products were obtained though vaccum distillation.β-cyclodextrin and glycidyl benzoate, glycidyl propionate, glycidyl acetate, reacted in organic solvent and goal product were

先以苯甲酸钠、乙酸钠、丙酸钠和环氧氯丙烷为原料在相转移催化剂的作用下分别合成了苯甲酸缩水甘油酯、乙酸缩水甘油酯和丙酸缩水酯，经过减压蒸馏，得到相应的纯品；β-环糊精和苯甲酸缩水甘油酯、乙酸缩水甘油酯、丙酸缩水甘油酯在有机溶剂中反应，经过硅胶色谱柱分离，得到了相应的产品，产品经过TLC、IR、1H NMR、MS表征，并研究了温度、反应时间、催化剂等几个因素对反应工艺的影响，结果表明温度和催化剂对反应的快慢有较大影响。

The most relevant circuit laws being violated are those laws pertaining to a closed loop circuit: Ohm's Law, Joule's Law, Kirchoff's Mesh Law, etc. According to ordinary theory, a working circuit must be a complete loop of some sort.

最相关的电路的法律受到侵犯，是那些有关的法律闭环电路：欧姆定律，焦耳定律， kirchoff的网格法等，根据一般的理论，一个工作小组，电路必须有一个完整的闭环某种形式的。

In the negative and interrogative forms, of course, this is identical to the non-emphatic forms.

。但是，在否定句或疑问句里，这种带有"do"的方法表达的效果却没有什么强调的意思。

Go down on one's knees;kneel down

屈膝跪下。。。下跪祈祷