两次

This article introduces some encryption methods in common use, and analyses their advantages and disadvantages, and at last brings forward the scheme of "double software with certificating for two times ".

本文介绍几种目前常用的加密方法，并分析了它们的优缺点，最后提出了自己设计的&双软件两次认证&方案。关键词：软件保护；软件加密；双软件两次认证

When he asked why,she answered,"Last night when it cuckooed midnight,it cuckooed three times,said "crap,cuckooed one more time ,farted,cuckooed three times ,cleared its throat,cuckooed two more times and then started giggling.

他问为什么，妻子说，昨天午夜咕咕钟叫的时候，它先咕咕了三次，说&废物&，又咕咕了一次，farted，再咕咕了三次，然后清了请嗓子，咕咕了两次，最后咯咯地傻笑起来。

When he asked why, she answered,"Last night when it cuckooed midnight, it cuckooed three times, said 'Crap!,' cuckooed one more times, farted, cuckooed three times, cleared its throat, cuckooed two more times and then started giggling."

当这个人问为什么的时候，他的妻子回答说：昨天夜里当它咕咕十二点的时候，它咕咕了三次，说：&废物&再叫了一次，farted，然后又叫了三次，清了清嗓子，又叫了两次之后开始格格笑。

When he asked why, she answered,"Last night when it cuckooed midnight, it cuckooed three times, said 'Crap!,' cuckooed one more times, farted, cuckooed three times, cleared its throat, cuckooed two more times and then started giggling."

当他问这是问什么时，妻子回答道：&昨天午夜咕咕钟叫的时候，它先咕咕了三次，说&废物&，又咕咕了一次，放了个屁，再咕咕了三次，然后清了请嗓子，咕咕了两次，最后咯咯地傻笑起来。&

Then they all knew who 'twas that had been undoing them in the cabin, and twice Hook essayed to speak and twice he failed.

这一来，他们才知道在舱里作怪的是谁。胡克两次想说话，两次都没说出来。

Having piggybacked two breakups, I felt as if I'd been through a double divorce .

这两次感情创伤让我觉得仿佛经历了两次离婚。

The last two Fed tightenings contributed to swoons, even though they weren't aggressive. The Fed raised rates by only 1.75 percentage points between June 1999 and May 2000. Yet that contributed to a crash in equity markets. While the Fed funds rate did move up from emergency levels between mid-2004 and mid-2006, it was done gradually, and the real Fed funds rate was actually below 1% from late 2001 to early 2006, illustrating the Fed's extreme dovishness.

美联储前两次紧缩措施都导致了问题，虽然那两次措施规模并不大。1999年6月-2000年5月，美联储仅仅将利率上调了1.75个百分点，然而却造成证券市场崩溃。2004年中-2006年中，联邦基金利率较紧急状态水平有所上调，但还是逐步进行的，从2001年底到2006年初的实际利率其实不到1%。

The products were identified by IR,NMR,MS and elemental analysis. In our method,K.OH was used in place of NaOH to synthesize benzyl ester of 3,5-dimethyl-4-hydroxybenzoic acid,2',6'-dimethyl-4'-(n-succinimidyloxycarbonyl) phenyl-acridinium-9-carboxylate was purified on a silica gel column with chloroform/ethylacetate(4:l,v/v) as eluent and further purified by triturating with hexane/acetone(2:l,v/v).The luminescence produced by DMAE-NHS is a flash light with maximumemission at 0.4s and decay half-time of 0.9s. The luminescence intensity is 6.11x10 cps/mol,which is affected by the composition of trigger and surfactant.

DMAE·NHS的合成是本论文的关键和难点，我们对文献方法进行改进：文献方法用氢氧化钠与3，5-二甲基-4-羟基苯甲酸反应制得3，5-甲基-4-羟基苯甲酸钠，再用3，5-二甲基-4-羟基苯甲酸钠与苄氯作用制备3，5-二甲基-4-羟基苯甲酸苄酯，我们用氢氧化钾代替氢氧化钠，使合成取得成功；在合成2'，6'-二甲基-4'-苯基-吖啶-9-甲酸酯时，文献方法对粗产品进行两次硅胶柱层析纯化，第一次柱层析用氯仿/乙酸乙酯(4：1，Ⅴ：Ⅴ)作溶剂和淋洗剂，第二次柱层析用己烷/丙酮(2：1，Ⅴ：Ⅴ)作溶剂和淋洗剂，按照文献方法得到的不是所需要的化合物，我们只进行第一次柱层析纯化，然后用己烷/丙酮(2：1，Ⅴ：Ⅴ)进行研磨，过滤，洗涤，除去溶于己烷/丙酮(2：1，Ⅴ：Ⅴ)的部分，得到所需要的产品。

He has lived through two wars and two revolutions.

他经历了两次战争和两次革命。

Was there not a certain Monsieur Mazers de Latude, who had the bad fortune to offend the all-accomplished Madame de Pompadour, who expiated his youthful indiscretion by a life-long imprisonment; who twice escaped from prison, to be twice cast back into captivity; who, trusting in the tardy generosity of his beautiful foe, betrayed himself to an implacable fiend?

不是有过一位马泽·德·拉蒂德先生①，倒了霉，冒犯了多才多艺的德·蓬帕杜夫人，由于他年轻失检，她便罚他终生监禁；他两次越狱，两次被逮归案；他深信他那美丽敌人的迟迟不至的宽宏大量，结果反而帮助一个不共戴天的魔鬼害苦了他自己吗？

Since historical times,England ,where the early inhabitants were Celts, has been conquered three times .

从有历史以来，英国，在此地早期居住的是凯尔特人，已经被征服了三次。

Bluetooth OBEX File Transfer Enables the sending and receiving of files on your phone via Bluetooth.

蓝牙OBEX文件移动允许经过蓝牙传送和接受文件。。。。