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问题 问答题 简答题

造成臭氧层破坏的主要气体是什么？破坏机理是什么？

答案

参考答案：

造成臭氧层破坏的主要气体包括NOX、CLOX、HOX等。其中氯氟烃气体为主。破坏机理：以氯氟甲烷气体为例：

CFCL3+hvCFCL2+CL

CFCL2+hvCFCL+CL

CL+O3CLO+O2

CLO+OCL+O2

O3+O2O2

多项选择题 案例分析题

患者女性，54岁：上腹部隐痛不适1年半，加重3个月入院，上腹痛不规则，偶伴嗳气，饭后饱胀。近一个月体重减轻3公斤，大小便正常，原有慢性萎缩性胃炎病史，体验：消瘦，左锁骨上可扪及一约花米大小淋巴结，质中偏硬。腹平软，剑突下偏左轻压痛，左上腹近剑突下似可扪及一肿块，界线不清，肝脾肋下未及，腹水征（-）。

手术切除肿癌上下各5cm以上胃（95%胃）．切除脾、胰体尾，胃结肠韧带及大同膜，清扫贲门左右、小大弯侧、幽门上下、胃左动脉旁、肝总动脉旁、腹腔动脉周围、脾门、脾动脉旁淋巴结，病检淋巴结未发现癌。此手术属以下哪几项？（）

A.R0

B.R1

C.R2

D.R3

E.R4

F.绝对根治

G.相对根治
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单项选择题

Observe that for the programmer, as for the chef, the urgency of the patron (顾客) may govern the scheduled completion of the task, but it cannot govern the actual completion. An omelette (煎鸡蛋) , promised in two minutes, may appear to be progressing nicely. Butwhen it has not set in two minutes, the customer has two choices--waits or eats it raw. Software customers have had (116) choices.
Now I do not think software (117) have less inherent courage and firmness thanchefs, nor than other engineering managers. But false (118) to match the patron’s desireddate is much more common in our discipline than elsewhere in engineering. It is very (119) to make a vigorous, plausible, and job risking defense of an estimate that is derived by no quantitative method, supported by little data, and certified chiefly by the hunches of the managers.
Clearly two solutions are needed. We need to develop and publicize productivity figures, bug-incidence figures, estimating rules, and so on. The whole profession can only profit from (120) such data. Until estimating is on a sounder basis, individual managers will need to stiffen their backbones and defend their estimates with the assurance that their poor hunches are better than wish derived estimates.

A．easy

B．difficult

C．simple

D．painless
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