普鲁卡因注射液与氯丙嗪注射液混配生成沉淀是由于()
A.pH值的改变
B.直接反应
C.溶媒组成的改变
D.电解质的盐析作用
E.聚合反应
参考答案:B
学生贷款的贷款对象一般是( )。
A.实行专业奖学金制度的在校学生
B.无力解决在校学习期间生活费的全日制本、专科在校学生
C.年满18周岁,具有完全民事行为能力的在校大学生、研究生
D.无力支付学费、住宿费和生活费的全日制本、专科学生(含高职生)、研究生和第二学士学位学生
An analog signal’s characteristic quantity representing data may 66) . at any instant, any value within a continuous (67) . For example, an analog signal may follow continuously the values of another physical quantity representing data.
A discrete signal is composed of (68) elements in time, each element having one or more characteristic quantities which can represent data. Examples of characteristic quantities are amplitude, waveform, (69) , and position in time. A digital signal is a special case of discrete signals, in which data are represented by a (70) number of well-defined discrete values that one of its characteristic quantities may take in time.
(68)处填()。
A.sequent
B.contiguous
C.following
D.successive