衡量先进性的主要内容有( )等。A．产品的水平和档次，属于哪个年代、哪一代产品 B

金属钛被称为铁和铝之后崛起的“第三金属”，常见化合价为+4。它是空间技术、航海、化工、医疗上不可缺少的材料。

工业上用钛铁矿（主要成分FeTiO₃）制备金属钛的一种工艺流程如下图（部分产物略去）：

（1）步骤①反应的化学方程式为：2FeTiO₃ + 6C + 7Cl₂2FeCl₃ + 2TiCl₄ + 6CO，还 原剂是　　   　  　，每生成1mol TiCl₄转移              mol电子。

（2）步骤②分离出TiCl₄的方法，利用了TiCl₄与FeCl₃　 　　　    的不同。

（3）步骤④反应的化学方程式为______________            __________，该反应在氩气中进行的理由是_________                _____________________。

（4）绿色化学提倡物料循环。以上流程中，可用于循环的物质除Cl₂、Mg外，还有___。

古希学者亚里士多德认为：如果要使一个物体持续运动，就必须对它施加力的作用．而伽利略则认为：运动物体并不需要力来维持．到底谁说得对呢？为了探究这个问题．小明和同学们设计了如图所示的实验。

（1）要探究运动到底需不需要力来维持，只需研究力对运动物体的影响，所以小明让一辆运动的小车在不同的阻力作用下研究它的速度变化．小明在实验中是如何让小车受到不同阻力的？

（2）为了探究不同阻力对运动的影响，我们应该保持小车受不同阻力前的速度是相同的，你认为小明是如何做到这一点的？

（3）请将小明在本实验中的结论填写完整：平面越光滑，小车运动的距离越_________，速度减小得越_________.。

（4）根据小明的结论，你能推理出若小车不受阻力，将做什么运动吗？

当归补血汤的主治证候中没有

A．烦渴欲饮

B．四肢厥冷

C．肌热面红

D．脉洪大而虚，重按无力

E．产后血虚发热头痛

木家具组装分部件组装和整体组装，组装前应将所有的结构构件用细刨刨光，然后按顺序逐渐进行装配，装配时应注意构件的部位和( )。

A．大小面

B．正反面

C．粘接面

D．安置面

A sticking plaster may appear to be a grossly inadequate treatment for a paraplegic. Attach a few electrodes, though, and a device that resembles such a dressing could help translate into actions the thoughts of people who are paralysed. In 2008 a practical version will be shown to work and the first individuals will be recruited to try them for real.

Paralysis is a breakdown in communication. The brain does not t0rget how to ride a bicycle. 41. ____________________________________.

John Donoghue of Brown University in Rhode Island has been working on how to restore that link. He has shown that the technology he has developed works, albeit only for a handful of people who were prepared to endure having a tangle of wires dangling from their heads. In 2008 Mr. Donoghue and his colleagues will turn their device into something that looks like a hearing aid and whose use could become almost as routine.

42. ______________________________. When the nerve cell fires, this electrical activity will be picked up by the wire and conveyed to the silicon chip.

43. ____________________________________. Power will come via an inductive coil placed under the scalp and next to another on top of the scalp, which will be attached to a battery. This, and a computing unit worn on a belt, will be the only parts visible outside the body. Ultimately the team intends to implant the computer unit in the chest, connected to the brain by a fibre-optic cable.

The researchers reckon their device will be able to direct a motorised wheelchair or move a robotic hand. But they also want to restore to paraplegics the use of their own bodies. 44. ______________________________. Connecting the two systems together would mimic the way in which the body normally works. But restoring useful movement to paraplegics involves more than making muscles work once more. It also means restoring a capability that most able-bodied people do not realise they have: the use of sensory feedback to fine-tune actions. 45. __________________________________________.

In order to achieve this, in 2008 Mr. Donoghue and his colleagues will develop their system to run in reverse. Because the monkeys used in the tests will not be paralysed, the implant will not only broadcast what the brain is doing but also eavesdrop on what happens to the nerve cells when they are receiving information. This could then be mimicked in people. The idea is that paralysed people could operate, say, a robotic hand with sensors that collect information about the pressure and temperature they encounter and convey these data back to the brain. That is, the human brain will be stimulated to feel what the robot senses. Not bad for a device that looks like a sticking plaster.

[A] The researchers will implant a silicon chip the size of a small button into the brains of monkeys. The chip will be fitted with an array of 100 thread-like gold wires, each of which will be attached to a nerve cell in the brain

[B] Hence their involvement with Hunter Peckham of Case Western Reserve University. He is developing a system which electrically stimulates muscles to make them move once again.

[C] Years after paralysis has struck, the same nerve cells fire when someone is thinking about moving ; it is just that the rest of the body does not receive the message.

[D] There are many kinds of sticking plasters, which are now in wide use in many countries. But sticking plasters are not very adequate to treat paraplegics and paralytics.

[E] Reach out to pick up a cup of hot tea from a vending machine and, as your hand touches the cup, it subtly adjusts its grip so that enough strength is used to lift the cup without crushing it and burning your fingers.

[F] The next step will be to transmit this information from the skull to the outside world. A second device will be attached to the silicon chip to do this. It will transmit data through the skin using pulses of infra-red light, just like a remote control.

[G] A robotic hand is equipped with sensors, which are mainly used to collect related information and transmit it to the outside chip. Then this chip will process the message and inform the paraplegic to move his or her muscles.

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