一个瓶子最多能装0.5kg的水,最多能装_________ m3的酒精.(ρ酒精

题型:填空题

问题:

一个瓶子最多能装0.5kg的水,最多能装_________ m3的酒精.(ρ酒精=0.8×103kg/m3);将体积分别为V1、V2的水和酒精混合,发现混合后液体的总体积V_________ V1+V2,(选填“<”、“=”或“>”)这一实验表明液体分子间有_________

考点:密度公式的应用分子间的空隙
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某同学为了探究废弃塑料薄膜混杂在土壤中对植物生长的影响.设计了如下实验:取两个同样的花盆,找5-8个废旧塑料袋,剪成小碎片,再取约4kg的腐殖质,分为两等份,一份直接装入花盆中,另一份与塑料碎片混匀后,装入另一花盆中,将两株生长状况相同的同种花草分别栽到两个花盆中,在同样条件下(温度、浇水、光照等)让其生长6-8个月后观察二者的生长状况.

(1)你估计,一个月后,二者的生长情况分别为:______.

(2)在上述实验中,强调让两株植物在相同条件(温度、浇水、光照等)下生长,这样做的目的是______.

(3)你估计,在上述实验过程中,可能出现什么意外情况影响实验的正常进行?______.

(4)通过该实验,你能得到什么启示?你认为应向使用塑料薄膜作大棚或地膜的农民提出建议为______.

题型:填空题

消化性溃疡患者节律性疼痛变为持续性,进食或服用制酸药后长时间不能缓解,并向肩背部放射时,可能是发生了 ()

A.癌变

B.出血

C.胃底静脉曲张

D.幽门梗阻

E.穿孔

题型:填空题

我国实施西部大开发,加强基础建设,国家修建长4200千米“西气东输“管道,将新疆的天然气东送,经过甘、宁、陕、晋、豫、皖、苏等省(区),最后到达上海,供应长江三角洲地区和沿线各省的居民和工业用气.

(1)在“西气东输“管道经过的省(市、区)中,面积最大的是______,经     济最发达的是______.

(2)我国“西气东输“工程,西起______,东到______市,沿途经过的地形区有:G______盆地、E______高原、D______ 高原、华北平原、______平原.

(3)由于沿线城市可用清洁的燃料取代部分生产、生活中使用的煤炭,这将降低城市环境中的______ 污染.

(4)下列因素中,属于修建“西气东输“管道线路走向,所要考虑的经济因素是______

A.地形因素  B.城市分布  C.气候类型   D.河流状况.

题型:填空题

神经鞘瘤与神经纤维瘤的鉴别要点中,下列错误的是()

A.神经鞘瘤来源于神经鞘细胞,神经纤维瘤来源于神经束膜、外膜或内膜等支持细胞

B.神经鞘瘤最常见部位为正中神经干、尺神经干、坐骨神经及桡神经,神经纤维瘤可发生于神经末梢或神经干的任何部位

C.神经鞘瘤多为单发,神经纤维瘤可单发或多发,以多发者为常见

D.神经鞘瘤之神经纤维穿过瘤体,神经纤维瘤之神经纤维并不穿过肿瘤组织

E.神经鞘瘤可与神经纤维完整分离,而切除神经纤维瘤必须切断神经纤维

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(46) Surprisingly enough, modern historians have rarely interested themselves in the history of the American South in the period before the South began to become self-consciously and distinctively "Southern"—the decades after 1815. Consequently, the cultural history of Britain’ s North American empire in the seventeenth and eighteenth centuries has been written almost as if the Southern colonies had never existed. The American culture that emerged during the Colonial and Revolutionary eras has been depicted as having been simply an extension of New England Puritan culture. However, Professor Davis has recently argued that the South stood apart from the rest of American society during this early period, following its own unique pattern of cultural development. (47) The case for Southern distinctiveness rests upon two related premises: first, that the cultural similarities among the five Southern colonies were far more impressive than the differences, and second, that what made those colonies alike also made them different from the other colonies. The first, for which Davis offers an enormous amount of evidence, can be accepted without major reservations; the second is far more problematic.

What makes the second premise problematic is the use of the Puritan colonies as a basis for comparison. Quite properly, Davis decries the excessive influence ascribed by historians to the Puritans in the formation of American culture. Yet Davis inadvertently adds weight to such ascriptions by using the Puritans as the standard against which to assess the achievements and contributions of Southern colonials. (48) Throughout, Davis focuses on the important, and undeniable, differences between the Southern and Northern colonies in motives for and patterns of early settlement, in attitudes toward nature and Native Americans, and in the degree of receptivity to metropolitan cultural influences.

(49) However, recent scholarship has ply suggested that those aspects of early New England culture that seem to have been most distinctly Puritan, such as the p religious orientation and the communal impulse, were not even typical of New England as a whole, but were largely confined to the two colonies of America. Thus, what in contrast to the Puritan (Northern) colonies appears to Davis to be peculiarly Southern—acquisitiveness, a p interest in politics and the law, and a tendency to cultivate metropolitan cultural models—was not only more typically English than the cultural patterns exhibited by Puritan Massachusetts and Connecticut, but also almost certainly characteristic of most other early modern British colonies from Barbados north to Rhode Island and New Hampshire. (50) Within the larger framework of American colonial life, then, not the Southern but the Northern colonies appear to have been distinctive, and even they seem to have been rapidly assimilating to the dominant cultural patterns by the last Colonial period.

(50) Within the larger framework of American colonial life, then, not the Southern but the Northern colonies appear to have been distinctive, and even they seem to have been rapidly assimilating to the dominant cultural patterns by the last Colonial period.

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