试题与答案

摩擦分为干摩擦;()、混合摩擦和()。

题型:填空题

题目:

摩擦分为干摩擦;()、混合摩擦和()。

答案:

参考答案:边界摩擦;流体摩擦

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题型:阅读理解与欣赏

阅读下面的文字,完成下面的题。  

  汉代画像石、泥俑、古墓壁画刻画的形象多是一种粗线条粗轮廓的形象,然而汉代艺术就在这粗轮廓的整体形象的飞扬流动中,表现出力量、运动、气势之美。

  在汉代艺术中,力量、运动、气势就是它的本质。在汉代艺术品里,动物形象狂奔乱跑,活泼跳跃,不像唐代那样尽管威武雄壮却静态伫立。人物形象虽然有时形态是静止的,却包含着内在的力量、运动、气势。人物不是以其精神、心灵、个性或内在状态而是以其事迹、行动来表现他存在价值的。一往无前不可阻挡的力量、运动和气势,构成了汉代艺术的美学风格。它与六朝之后安详凝练酌静态姿势和内在精神形成了鲜明的对照。

  正因为是靠动作、情节而不是靠细微的精神面容、声音笑貌来表现对世界的征服,于是粗轮廓的写实、不需要细部的忠实描绘,便构成汉代艺术的“古拙”外貌。汉代艺术形象看起来是那样笨拙古老,但这不但没有减弱反而增强了力量、运动、气势的美。“古拙”反而是构成这种气势美不可分割的因素。如果没有这种笨拙,也就很难展示出那外在动作姿态的力量、运动、气势感了。过分弯的腰,过分长的袖,过分显示的动作姿态“笨拙”得不合现实比例,却非常合乎展示力量、运动的夸张需要。“气势”与“古拙”在这里浑然一体。

  如果拿汉代艺术品与后代艺术品相比较,汉代艺术尽管处在草创阶段,显得幼稚、粗糙、简单和拙笨,但是那种运动、速度的韵律感,那种生动活跃的力量、运动、气势,就愈显优越和高明。汉代艺术那种蓬勃旺盛的生命,那种整体性的力量和气势,是后代艺术所难以企及的。

  汉代艺术不懂后代讲求的“以虚当实”“计白当黑”之类的规律,画面总是塞得满满的,几乎不留空白。然而,它留给人们以后代空灵精致的艺术所不能替代的丰满朴实的意境。它更使人感到饱满和实在。与后代的巧、细、轻相比,它确实显得拙、粗、重。它以简化的轮廓为形象,使粗犷的气势不受束缚而更有非写实的浪漫风味。它因气势与古拙的结合,充满了整体性的力量、运动感而具有浪漫风貌。当时民间艺术与文人艺术尚未分化,汉代艺术呈现出来更多整体性的民族精神。如果说唐代艺术更多表现了中外艺术的交融,那么汉代艺术则突出地呈现着中华本土的传统:那由楚文化而来的天真狂放的浪漫主义,那在满目琳琅的人对世界的行动征服之中的古拙气势的美。(取材于李泽厚《美的历程》)

1.下列说法符合文意的一项是(          )。   

A.汉代艺术品中的动物、人物形象均以运动姿态出现,表现出强烈的力量、气势之美。   

B.汉代艺术品表面上呈现出幼稚、简单与粗糙,实际上正是一种成熟与完美的表现。   

C.与汉代艺术风格相比较,后代轻、细、巧的艺术风格显得过于写实没有浪漫气息。   

D.与唐代艺术不相同,汉代艺术突出地体现着中华本土的传统以及整体性的民族精神。

2.汉代艺术品中的形象是如何表现出内在的力量、运动、气势之美的?   

                                                                                          

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题型:单项选择题

Animal studies are under way, human trial protocols are taking shape and drug makers are on alert. All the international health community needs now is a human vaccine for the bird flu pandemic sweeping a cluster of Asian countries.

The race for a vaccine began after the first human case emerged in Hong Kong in 1997. Backed by the World Health Organization (WHO), three research teams in the US and UK are trying to create a seed virus for a new vaccine. Their task is formidable, but researchers remain optimistic." There are obstacles, but most of the obstacles have been treated sensibly," says Richard Webby, a virologist at St. Jude Children’s Research Hospital in Memphis, Tennessee.

The biggest challenge is likely to be the rapidly mutating virus. Candidate vaccines produced last year against the H5N1 virus are ineffective against this year’s strain. Scientists will have to constantly monitor the changes and try to tailor the vaccine as the virus mutates. They can’t wait to see which one comes next.

The urgency stems from fears that I-ISN1 will combine with a human flu virus, creating a pathogen(病原体) that could be transmitted from person to person. But if people have no immunity to the virus, the strain may not mutate as rapidly in people as it does in birds.

To quickly generate the vaccine, researchers are using reverse genetics, which allows them to skip the long process of searching through reassorted viruses for the correct genetic combination. Instead, scientists clone sequences for hemagglutinin(红血球凝聚素) and neuraminidase(神经氨酸苷酶), the two key proteins in the virus. The sequences are then combined with human influenza genes to create a customized reference strain.

Because products developed with reverse genetics have never been tested in humans, the candidate vaccines will first have to clear regulatory review. In anticipation, the US Food and Drug Administration (FDA) and the European Agency for the Evaluation of Medicinal Products (EMEA) are both preparing pandemic response plans. The EMEA has produced a fist-track licensing program, an industry task force and detailed guidance for potential applicants.

In Europe, a reassortant influenza virus -- but not the inactivated vaccine -- produced by reverse genetics would be considered a genetically modified organism, and manufacturers would need approval from their national or local safety authorities. The WHO has prepared a preliminary biosafety risk assessment of pilot-lot vaccine, which could help speed up the review.

A preliminary version of their protocol calls for several hundred subjects, beginning with a group of young adults and gradually expanding to include those most susceptible to the flu -- children and the elderly." If we had product," says Lambert," it would probably be a couple of months at the earliest before we have early data in healthy adults.

What is the author’s attitude towards the newly developed bird flu vaccine()

A. Slightly approves of

B. Depicts neutrally

C. Slightly disapproves of

D. Completely rejects

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