IgM呈单克隆性明显增高的是（） A.初期病毒性肝炎 B.肝硬化 C.SLE D.原

叠氮酸（HN₃）与醋酸酸性相近，其盐稳定，但撞击时会发生爆炸生成氮气．有关叠氮酸的叙述中正确的是

①NaN₃ 的水溶液呈碱性          ②HN₃ 的固体属于共价化合物

③NaN₃ 的固体属于离子化合物    ④NaN₃可用于小汽车防撞保护气囊（　　）

A．①②③

B．②③④

C．①③④

D．①②③④

水是生命之源，也是人类最宝贵的资源。

（1）自然界中的水都不是纯水，净水时需加入明矾的目的是       。

（2）欲除去水中不溶性杂质，需进行过滤操作，该操作过程中玻璃棒的作用是           。

（3）若要测定黄浦江水的酸碱度，最适宜的试剂或用品是        （填序号）。     

A．紫色石蕊试液

B．pH试纸

C．石灰石

D．无色酚酞试液（4）某同学在完成电解水实验时，发现负极产生了10mL气体，则正极产生的气体体积是     。请再举一实例说明水是由氢元素和氧元素组成的（用化学方程式表示）         。

（5）“84”消毒液的有效成分NaClO中的氯元素的化合价为       ；Cl₂常作自来水消毒剂，其实验室制法为， 则X的化学式为      ；此反应中属于氧化物的是        （填化学式），此反应中含有游离态氯元素的物质是         （填化学式）。

声波透射法适用于（）桩身完整性检测，判定桩身缺陷的程度并确定其位置。

A.沉管灌注桩

B.PHC管桩

C.未预埋声测管的混凝土灌注桩

D.已预埋声测管的混凝土灌注桩

运用踩跷法时应（）

A.医者弹跳时足尖不离开患者腰部

B.患者不用呼吸配合

C.踩踏速度可以无节奏

D.应在患者腹部和膝部加垫枕头

E.腰椎间盘突出症患者不宜使用此法

When the system upon which a transport entity is running fails and subsequently reatarts, the ______ information of all active connections is lost. The affected connections become half-open, as the side that did not fail does not yet realize the promble.
The still active side of a half-open connections using a ______ timer. This timermeasures the time transport machine will continue to await an ______ of a transmitted segment after the segment has been retransmitted the maximum number of times. When the timer ______, the transport entity assumes that either the other transport entity or the intervening network has failed. As a result, the timer closes the connection, and signals an abnormal close to the TS user.
In the event that a transport entity fails and quickly restart, half-open connections can be teminated more quickly by the use of the RST segment. The failed side returns an RST_i to every segment i that it receives. When the RST_i reaches the other side, it must be checked for validity dased on the ______ number i, as the RST could be in response to an old segment .If the reset is valid, the transport entity performs an abnormal termination.

A. resetB. acknowledgment C. synchroizer D. sequence