问题 填空题

如图所示为电磁选矿机的示意图,漏斗M中装的是矿石,电磁铁固定在转筒内,当矿石从漏斗经转筒落入A、B两容器时,落入A中的是______落入B中的是______,(选填“铁磁性物质”或“非铁磁性物质”).其原因是______.

答案

如图所示是电磁选矿机的示意图,其中M为矿石,转筒内有电磁铁,即由于电磁铁能吸引铁磁性物质,故落入B中的是铁矿石,而非铁矿石在重力的作用下,在A处就下落.

故答案为:非铁磁性物质;铁磁性物质;磁铁能够吸引铁磁性物质.

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Sadness isn’t manly—this Eric Weaver knew. When depression engulfed this New York police sergeant, it took a different guise: a near-constant state of anger. "One minute I’d be okay and the next minute I’d be screaming at my kids and punching the wall," he recalls. "My kids would ask, ’What’s wrong with Daddy Why’s he so mad all the time’" For years, Weaver didn’t know what was wrong.

Weaver’s confusion about what tortured him was not unusual. Roughly a third of the 18 million or more Americans who suffer depression each year are men. Yet all too often, experts say, men fail to recognize the symptoms and get the treatment they need.

For years, experts suspected that gender makes a big difference in depression. Studies from New York to New Zealand have repeatedly found the same startling statistic: About twice as many women as men suffer from depression. That finding was considered one of the bedrock facts of modern mental health. Yet it has recently come under attack from critics who are concerned about underreporting of male depression.

William Pollack, Director of the Center for Men at McLean Hospital, is leading the charge against the well-entrenched depression gender gap. He argues that men’s rate of depression may be nearly equal to women’s. Just look at suicide rates, he says: Male suicides outnumber females four to one. That ratio "is way too high to say that men’s depression numbers are so low," he notes.

Pollack and others contend that male depression goes unrecognized because, unlike the female version, it often doesn’t fit the textbook signs—at least in the early stages. Clinical depression at later stages looks much the same in both sexes. But in the prelude to a breakdown, that deepening despair is often expressed in very different ways. Instead of being weepy, men are more apt to be irritable and angry—moods that aren’t included in the classic diagnostic tests. "Their sadness and helplessness are hidden behind a mask of anger," says Pollack.

"Men tend to act out" to avoid dealing with uncomfortable feelings, adds Fredric Rabinowitz, a psychologist who works primarily with men. If they feel bad, they’re apt to get into fights on the job or at home, withdraw from family and friends, become obsessed with work or hobbies. Most significantly, men often turn to drinking or drugs. Men have two to four times the rate of substance abuse problems as women, and Pollack contends that if this was recognized as a sign of depression, the gender gap would substantially narrow.

Which of the following would be the best title for the text()

A. Male Depression: Re-examined

B. Symptoms of Depression: Gender Difference

C. Male Depression: Underlying Causes

D. Mask of Anger: Men Under Stress