采用扩频通信可以将被噪声淹没的信号正确解调出来，提高通信的抗干扰能力。

关于常用氧代谢的监测指标，描述不正确的是

A．DO₂是每分钟心脏向外周组织输送的氧量，血红蛋白、SaO₂或CO中任意指标的改变均可导致其变化
B．VO₂是每分钟机体实际的耗氧量。在正常情况下，反映机体对氧的需求量，并代表组织的实际需氧量
C．O₂ER是每分钟氧摄取率，即组织从血液中摄取氧的能力，反映组织呼吸与微循环灌注及细胞内线粒体功能
D．SvO₂是来自全身血管床的混合静脉血氧饱和度的平均值，代表全身组织水平氧供和氧耗的平衡，可用以判断危重症患者整体氧输送和组织的摄氧能力
E．ScvO₂是通过中心静脉导管测量得到的血氧饱和度，可以很好地反映SvO₂的变化

C

If you are a fruit grower—or would like to become one—take advantage of Apple Day to see what’s around. It’s called Apple Day but in practice it’s more like Apple Month. The day itself is on October 21, but since it has caught on, events now spread out over most of October around Britain.

Visiting an apple event is a good chance to see, and often taste, a wide variety of apples. To people who are used to the limited choice of apples such as Golden Delicious and Royal Gala in supermarkets, it can be quite an eye opener to see the range of classical apples still in existence, such as Decio which was grown by the Romans. Although it doesn’t taste of anything special, it’s still worth a try, as is the knobbly(多疙瘩的) Cat’s Head which is more of a curiosity than anything else.

There are also varieties developed to suit specific local conditions. One of the very best varieties for eating quality is Orleans Reinette, but you’ll need a warm, sheltered place with perfect soil to grow it, so it’s a pipe dream for most apple lovers who fall for it.

At the events, you can meet expert growers and discuss which ones will best suit your conditions, and because these are family affairs, children are well catered for with apple-themed fun and games.

Apple Days are being held at all sorts of places with an interest in fruit, including stately gardens and commercial orchards(果园).If you want to have a real orchard experience, try visiting the National Fruit Collection at Brogdale, near Faversham in Kent.

What can people do at the apple events?（）

A. Attend experts’ lectures.

B. Visit fruit-loving families.

C. Plant fruit trees in an orchard.

D. Taste many kinds of apples.

上消化道出血可单纯表现为呕血或黑便，也可两者兼有，这取决于

A．原发病

B．出血部位

C．出血量

D．在胃内停留时间

E．以上均非

某小组同学对废干电池筒内的黑色固体(内含有MnO₂、NH₄Cl、ZnCl₂等)进行了如下图所示的实验：

(1)操作②的名称是                    ，该操作中玻璃棒的作用是                            。

(2)操作③灼烧滤渣黑色固体时，会产生一种使澄清石灰水变浑浊的气体，由此推测滤渣中除含有MnO₂外，还存在的物质是                          。

(3)操作④的试管中产生的气体使带火星的木条复燃，则该气体为                                 。

(4)已知在氯化锌溶液中逐滴滴入稀氨水，先生成Zn(OH)₂白色沉淀，然后溶解生成可溶于水的

Zn(NH₃)₄Cl₂。同学们对操作②的滤液中的成分进行探究。

谁负责制定建设工程的抗震设计规范？