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The influences of the shock thickness and Alfven waves on the particle acceleration by diffusive shock waves are numerically studied through solving one-dimensional diffusive equation including the second-order Fermi effect. It is shown that the spectral index of the energetic particles strongly depends on the shock thickness. For example, the spectral index increases from 2.1 to 3.7 in the low energy range of 3-10 MeV and from 2.5 to 5.0 in the high energy range of 20-60 MeV as the thickness increases. The spectral index decreases from 4.3 to 3.1 as the particle injection energy increases. The spectral index decreases from 4.0 to 1.8 at the quasi-steady stage with the enhancement of the compression ratio from 2 to 4. The results indicate that under the influence of Alfven waves, the energetic particle spectrum at lower energy becomes flat and the spectral index decreases from 2.5 to 0.6 in the low energy range of 3-10 MeV and from 11.6 to 5.0 in the high energy range of 20-60 MeV. At the same time, the rollover energy reaches 19.6 MeV. The spectral index decreases from 5.8 to 2.9 as the energy density of Alfven waves increase. All these results are basically consistent with the theoretical models, as well as the observations of typical energetic particle events.

通过数值求解包含二阶费米加速的一维扩散方程，探讨在准平行激波条件下激波厚度和级联阿尔芬波对粒子加速的影响，研究粒子分布函数的演化与激波厚度和阿尔芬波强度的内禀关系，计算结果表明：(1)考虑激波厚度时，谱指数明显依赖于激波厚度，随着厚度从0.32增大到2.56，低能端(3-10MeV)谱指数逐渐从2.1增加到3.7，高能端(20-60MeV)谱指数从2.4增大到5.0，能谱逐渐变软；当初始注入粒子动量增大1.3倍，质子能谱指数从4.3减小到3.1，且与零厚度激波加速的谱指数差值缩小；厚度不变时，随着压缩比从2增加到4，准稳态分布时低能端(3-10MeV)粒子能谱指数逐渐从4.0减小到1.8谱变硬；(2)在级联阿尔芬波的影响下，随着时间的增大，粒子在低能处(3-10MeV)的谱指数从2.5减小到0.6高能端(20-60MeV)谱指数从11.6减小到5.0，能谱变硬，拐点能量值从7.5MeV增大到为19.6MeV；随着波的能量密度增大，谱指数从5.8减小到2.9，这表明阿尔芬波强度越大，加速效率越高，通过与激波厚度解析结果和高能粒子事件的观测能谱比较发现两者是一致的，说明数值模拟结果是可靠的。

Mr Bail, a prize-winning novelist who wrote "Eucalyptus", is a critic parsimonious with his enthusiasms, but he has devoted many years to beating Fairweather out of the bush that was the artist's preferred habitat.

鲍尔写过获奖小说《桉树》；而作为一个文学评论家，他虽然吝惜表现自己的热情，却花费多年时间到费尔韦瑟所住的树林中，企图诱其出林。

From the conclusion, in order to improve the total exploitation amount or the total recovery coefficient, the government should allow enterprise to increase these abstraction of production cost such as keeping simple reproduction fee, security production cost, and ground collapse compensation fee as the increase in the exploitation quantity; count the taxes and fees based on the reserves; accurately estimate thee resource taxes and compensation fees of one ton of coal; and impose the total fees and taxes to be worked out before exploitation or at least in a shorter period after exploitation.

根据研究结论，为了提高煤炭资源总的开采量或总的回采率，政府应允许企业随着总开采量的增加而增加对维简费、安全生产费用、地面塌陷补偿费等各项生产成本的提取；按照核定储量计征税费；准确的估计吨煤的资源税和吨煤的补偿费；在开采前或者在很短的时间内征收计算出来的税费总额。

But over the next few years, Fermi will detect more and more bursts.

不过随着时间的推移，费米望远镜会不断发现更多的爆发点。

River Plate star Augusto Fernandez warns Lazio they are his number one choice, but time is running out.

河床队的明星球员奥古斯托。费尔南德斯提醒拉齐奥他们是他的第一选择，但是时间已经不多了。

I had decided about this farewell quite some time ago and the club and Ferrara are informed .

我决定对这个告别前一段时间，俱乐部和费拉拉被告知。

The model of multicenter extraction was brought forward on the base of Fick law. A mapping model of extraction time and concentration were set up according to the experiment.

在费克定律的基础上提出了多通道核浸提理论，建立了浸提时间与浸提浓度之间的映射模型。

Fiona : I'm just afraid I'll be wasting his time.

费欧娜︰我怕我是在浪费他的时间。

I am having a hard time figuring you out, Fischer.

我花了很多时间才看清楚你费舍尔

It took me a long time to get rid of him.

我费了很长时间才摆脱了他。

But we don't care about Battlegrounds.

但我们并不在乎沙场中的显露。

Ah! don't mention it, the butcher's shop is a horror.

啊！不用提了。提到肉，真是糟透了。