两倍的

Movement trajectories of electrons under complex field and state parameters when electrons return to the dielectric surface are obtained by simulation,such as impact energy and return time. Variation laws of electron movement with emergence angle and microwave electromagnetic parameters are also derived. The emergence angle of electron has significant effect on the movement of electron,and there is an emergence angle in which the electron has the maximum trajectory length and impact energy.

研究发现：电子出射角度对其运动状态有显著影响，电子存在运动轨迹最大的某一出射角度，该角度下电子拥有最大的撞击能量；微波电场幅值的增加将使电子撞击能量增加，返回时间减小，微波电场相位的变化使电子的撞击能量和返回时间呈周期振荡，这从本质上解释了电子数量在二次电子倍增过程中以微波频率两倍周期振荡的原因；随着微波频率的增加电子将由简单的类抛物线运动转变为复杂的振荡运动。

Variation laws of electron movement with emergence angle and microwave electromagnetic parameters are also derived. The emergence angle of electron has significant effect on the movement of electron, and there is an emergence angle in which the electron has the maximum trajectory length and impact energy, Impact energy will increase and return time will reduce as increasing the amplitude of electric field, and both parameter would oscillate with the phase of electric field, which can essentially explain that multipactoring electron number oscillates in twice the frequency with the increase of microwave frequency, electron trajectory will change from parabolic-like movement to complex oscillation.

研究发现：电子出射角度对其运动状态有显著影响，电子存在运动轨迹最大的某一出射角度，该角度下电子拥有最大的撞击能量；微波电场幅值的增加将使电子撞击能量增加，返回时间减小，微波电场相位的变化使电子的撞击能量和返回时间呈周期振荡，这从本质上解释了电子数量在二次电子倍增过程中以微波频率两倍周期振荡的原因；随着微波频率的增加电子将由简单的类抛物线运动转变为复杂的振荡运动。

The numerator in this fractional designation is known as the diametral pitch and controls the pitch diameter; the denominator, which is always double the numerator, is known as the stub pitch and controls the tooth depth.

在这一系列的分数中的分子是径节，径节的大小决定了节圆的直径；而分数中的分母通常是分子的两倍，分母是残余径节，它的作用是控制齿槽的深度。

Tooth Proportions.—There are 17 pitches: 2.5/5, 3/6, 4/8, 5/10, 6/12, 8/16, 10/20, 12/24, 16/32, 20/40, 24/48, 32/64, 40/80, 48/96, 64/128, 80/160, and 128/256. The numerator in this fractional designation is known as the diametral pitch and controls the pitch diameter; the denominator, which is always double the numerator, is known as the stub pitch and controls the tooth depth. For convenience in calculation, only the numerator is used in the formulas given and is designated as P. Diametral pitch, as in gears, means the number of teeth per inch of pitch diameter.

齿比——一共有17种齿比：2.5/5，3/6，4/8，5/10，6/12，8/16，10/20，12/24，16/32，20/40，24/48，32/64，40/80，48/96，64/128，80/160和128/256在这一系列的分数中的分子是径节，径节的大小决定了节圆的直径；而分数中的分母通常是分子的两倍，分母是残余径节，它的作用是控制齿槽的深度为了方便计算，在所有的公式中都使用分子作为计算参数，并且与齿轮的表示方式一样定义为径节P尺寸，也就是在节圆上，每英寸长度上的齿数

In our best cases in ilmenite, isotopic variation in 46TiO/48TiO the within run (1000 sec) scatter was only 0.7%(1σ), which is within factor of 2 of statistics limit. And the reproducibility in the case of 46TiO can be as good as ≦1%.

在钛铁矿中最好的情况下，1000秒的实验中，钛同位素46比48的偏差的一个标准差只有0.7%，是统计误差的两倍以内，并且在氧化钛形式当中的钛46的同位素比值的一个标准差小於1%。

7 To 3.3 V operating supply voltage 44.1 kHz sampling frequency 16.9344 MHz (384fs) system clock Built-in crystal oscillator circuit 16-bit, MSB rst, rear-packed serial data input format ( 64 fs bit clock) 8-times oversampling digital lter · 32 dB stopband attenuation ·+0.05 to -0.05 dB passband ripple Deemphasis lter operation · 36 dB stopband attenuation ·-0.09 to +0.23 dB deviation from ideal deem- phasis lter characteristics Attenuator · 7-bit attenuator (128 steps) set by microcontrol- ler Soft mute function set by parallel setting ·(approximately 1024/fs total muting time) Mono setting · Left or right channel mono selectable by micro- controller Built-in innity-zero detection circuit , two-channel D/A converter · 3rd-order noise shaper · 32fs oversampling Built-in 3rd-order post-converter low-pass lters 24-pin VSOP package Molybdenum-gate CMOS process

2.7至3.3 V工作电源电压为44.1千赫的采样频率16.9344兆赫（384fs）系统时钟内置晶体振荡器电路的16位，MSB在前，后包装的串行数据输入格式（64飞秒位时钟）8倍超采样数字滤波器·32分贝的阻带衰减·+0.05至-0.05分贝通带纹波去加重滤波器的运作·36 dB抑制频宽衰减·-0.09到0.23 dB的偏差认为不理想，症状困扰评估滤波特性衰减器·7位衰减器（128级）集由单片机在-莱尔软静音功能的平行设置·（共约1024/fs静音时间）单声道设置·左或右声道单声道微控制器可选的内置的无限零检测电路Δ，两通道的D / A转换器·第三阶噪声整形·32fs过采样内置三阶后转换器的低通滤波器24引脚VSOP封装钼栅CMOS工艺

With 55 pro bouts under his belt he has more than twice the number of fights that Chagaev has; and since the start of this decade, many of his opponents were top-10 contenders, such as Samuel Peter, Tony Thompson and Sultan Ibragimov, and experienced former titleholders such as Chris Byrd, Ray Mercer, Frans Botha, and Hasim Rahman.

经验：克里奇科是现役的重量级拳手中最具经验的，在他的头衔之下，历经55战，光数量就是恰加耶夫的两倍多；十年来，他的许多对手均位列重量级前十，如皮特、汤普森和伊布拉耶夫，还有经验丰富的前拳王如伯德、莫赛尔、博萨和拉曼。

In a country twice the size of California but with just two million inhabitants, the major cities, Swakopmund and Windhoek, the capital, feel like prefabricated alien entities plopped down without any local

纳米比亚的面积是加利福尼亚州的两倍，却只有二百万的居民，而国家的主要城市斯瓦科普蒙德和首都温得和克，看起来仿佛是外来的装配式预制产品，丝毫找不到任何的本地宗源。

If she spoke into your right ear, you would be twice as likely to give her a cigarette than if she asked by your left ear, according to a new study that employed this methodology in the clubs of Pescara, Italy.

研究人员在意大利佩斯卡拉的俱乐部采用这样的方法调查后得出了结论：如果她朝你的右耳喊，那么你给她香烟的几率将会是她朝你左耳喊的几率的两倍。

If she spoke into your right ear, you would be twice as likely togive her a cigarette than if she asked by your left ear, according to anew study that employed this methodology in the clubs of Pescara,Italy.

研究人员在意大利佩斯卡拉的俱乐部采用这样的方法调查后得出了结论：如果她朝你的右耳喊，那么你给她香烟的几率将会是她朝你左耳喊的几率的两倍。

Do you know, i need you to come back

你知道吗，我需要你回来

Yang yinshu、Wang xiangsheng、Li decang,The first discovery of haemaphysalis conicinna.

1〕 杨银书，王祥生，李德昌。安徽省首次发现嗜群血蜱。