三次

First, the speed of the reaction between mud acid and rock is very fast, the effective distance of acid is short, active acid can not reach deep formation.

首先，高温下常规土酸与地层矿物反应速度极快，酸液有效作用距离短，活性酸不能到达地层深部；其次，HF与铝硅酸盐的化学反应不是简单的一次反应，其副产物氟硅酸和氟铝化物还可与铝硅酸盐发生二次反应和三次反应，形成一系列不溶性的沉淀物，对储层造成严重伤害；第三，高温情况下酸液对井下管柱及工具腐蚀性很强，对缓蚀剂性能要求高。

The third, fifth and seventh harmonics were selected to calculate the pulse width jitter, and the corresponding product of pulse width and angular frequency, 7W, were 1.305, 2.175 and 3.045, respectively. With 25 kHz～5 MHz integration limits, the pulse width jitter was obtained to be 3.08ps.

选择脉冲重复频率的三次、五次和七次谐波的功率谱进行分析，三个谐波级次对应的脉冲宽度角频率积Tω分别为1.305，2.175和3.045，在25 kHz～5 MHz偏移频率范围内，得到的脉冲宽度抖动为3.08ps。

But since the 2nd after the auction ends, brilliance day is become did not entrust to the auction tardy however just pay an auction money, on April 15, shanghai inferior abstruse formal and written announcement auctions an orgnaization, because reason cannot pay corresponding auction money,say, will abandon buying suffer triplex group place holds equity, this is meant triplex the firm ascends the 3rd arsis to sell a station.

但自从第二次拍卖结束后，光华天成却迟迟未向拍卖委托方支付拍卖款项， 4月15日，上海亚奥正式书面通知拍卖机构，称因故无法支付相应的拍卖款项，将放弃买受三联集团所持股权，这就意味着三联商社将第三次登上拍卖台。

In this paper, we discuss the uniqueness limit cycle and the question of bifurcate about a class of general Liénard equation in the system .

当二次系统添加一个三次项变为三次系统后，这两个系统在原点附近的极限环的变化情况是否存在某种联系，亦是一个十分有趣的问题。

Then, a modifiable cubic polynomial curve is presented based on the basis functions, and the relation between the curve and the classical Bézier curves is discussed.

然后，基于该调配函数生成了一类可调控的三次多项式曲线，并讨论了该曲线与二次Bézier曲线及三次Bézier曲线之间的关系。

They are ①cubic plane curve constituted with projective pencil of lines and line eonic

进而证明三个定理：①一次线束和其射影对应的二次线束，所对应直线交点的轨迹为三次平面曲线

According to different characteristics of CMM error distribution, single error measurement model is built by cubic spline principle and double cubic spline function.

根据三种类型三坐标测量机误差分布的特征，提出了利用三次样条原理和双三次样条函数建立测量机一维和二维相关性误差模型。

In Chapter 3, a certain polynomial Hamilton system with 3 degree is given. By elliptic integral formulas, the monotonicity of the periodic orbits of this system is verified.

在众多文章中，讨论次谐轨的分岔都需要一个条件，那就是在同宿轨附近的周期轨是单调的，第三章给出了一个具体的三次平面Hamilton系统，利用椭圆积分公式验证了这个系统的一对同宿轨附近的周期轨的周期是单调的，这包含了三种情况，周期轨在右边同宿轨内部，在左边同宿轨内部以及在整个同宿轨圈外部。

Because of special geometry structure of three-cone bit, the top of formation will form a tri-spine well bottom while drilling with three-cone bit the drill string. It is the tri-spine well bottom that leads to the axial harmonic of vibration when the bit revolves a round and the three concavo-convex heave of bit and formation result in one time (1×rpm),two time (2×rpm), three time (3×rpm) turning table speed.

高岩由于三牙轮钻头的特殊几何结构，钻进过程中在岩层顶部容易形成一个三脊状井底，正是这一三脊状井底，当钻头旋转一周时钻柱轴向三次凸凹变化，由此在轴向产生1倍、2倍和3倍及其更高次倍于转盘转速rpm的谐波振动。

Because of special geometry structure of three-cone bit, the top of formation will form a tri-spine well bottom while drilling with three-cone bit the drill string. It is the tri-spine well bottom that leads to the axial harmonic of vibration when the bit revolves a round and the three concavo-convex heave of bit and formation result in one time (1×rpm),two time (2×rpm), three time (3×rpm) turning table speed.

高岩摘要：由于三牙轮钻头的特殊几何结构，钻进过程中在岩层顶部容易形成一个三脊状井底，正是这一三脊状井底，当钻头旋转一周时钻柱轴向三次凸凹变化，由此在轴向产生1倍、2倍和3倍及其更高次倍于转盘转速rpm的谐波振动。

The absorption and distribution of chromium were studied in ryeusing nutrient culture technique and pot experiment.

采用不同浓度K2CrO4(0，0.4，0.8和1.2 mmol/L)的Hoagland营养液处理黑麦幼苗，测定铬在黑麦体内的亚细胞分布、铬化学形态及不同部位的积累。

By analyzing theory foundation of mathematical morphology in the digital image processing, researching morphology arithmetic of the binary Image, discussing two basic forms for the least structure element: dilation and erosion.

通过分析数学形态学在图像中的理论基础，研究二值图像的形态分析算法，探讨最小结构元素的两种基本形态：膨胀和腐蚀；分析了数学形态学复杂算法的基本原理，把数学形态学的部分并行处理理念引入到家实际应用中。