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71.
超导量子干涉仪(SQUID)   总被引:2,自引:0,他引:2  
Clarke  J 周忠行 《科学中国》1994,(12):23-29,14
  相似文献   
72.
Vertesi J 《Endeavour》2004,28(2):64-68
In their race to provide the ultimate guide to the moon, two 17th-century astronomers proposed lunar maps and nomenclatures that they hoped would gain international currency. But the names we use today were those proposed by the Jesuit, a friend of Galileo's persecutors, in a book whose purpose was to refute the Copernican system once and for all. We now believe that Riccioli was wrong about the universe, but why do we still use his nomenclature? The keys to this foundational visual debate in astronomical image-making are the moon maps themselves.  相似文献   
73.
太阳能电池     
D.E 《科学中国》1990,(12):76-77
可弯曲的轻质太阳能电池展开竞争  相似文献   
74.
A century before the outbreak of bovine spongiform encephalopathy (BSE), Great Britain and North America grappled with pleuro-pneumonia - a disease in cattle that had equally maddening consequences. Towards the end of the 19th century, this condition was at the heart of a transatlantic trade dispute that lasted for decades and attracted the attention of livestock farmers, diplomats, shipping moguls, veterinarians, public health regulators and journalists the world over. Scientific controversy aggravated the situation when there were doubts about the scientific judgment of Privy Council veterinary officials, who were simultaneously conducting disease-diagnosis activities and pushing for tighter regulations at British ports. At this point, William Williams, principal of the New Veterinary College in Edinburgh, waded into this troubled arena. His strong convictions spawned a long-running disagreement with the British Government over the diagnoses of pleuro-pneumonia in cattle imported from the USA and Canada.  相似文献   
75.
76.
OBJECTIVES: The objectives of this work were to identify the sources of information currently received, information-seeking behaviours, information requirements and preferences for future information provision amongst health and social care professionals providing care to children with health care needs. METHODS: Data were collected using a cross-sectional postal questionnaire survey. RESULTS: A wide range of information resources was reported as being available to professionals. However, a large proportion of respondents found it necessary to perform additional searches for information, suggesting that current resources were not satisfying their needs. The majority of professionals reported a preference for electronic formats, whilst a smaller proportion preferred hard copy materials. Participants promoted the use of informal networks as a means of support and exchange of information. CONCLUSION: Supplementing the information that is provided in electronic and hard copy formats, by enhancing informal networks, may be the most effective way of meeting the information needs of this group of professionals.  相似文献   
77.
有人认为Google大量地数字化图书馆的馆藏图书,犹如给实体图书馆和图书馆员敲响了丧钟,还有一些人则认为Google此举是对版权法的挑衅。Google如何处理那些数字化图书是媒体报道的焦点。尽管Google的意图为人们所津津乐道,每个人都在期待着法院对版权纠纷的判决,人们也不禁想要知道:参与Google图书搜索项目的图书馆,如何使用那些从合作中得到的数字化拷贝呢?  相似文献   
78.
This updated edition of Care Practice Paper #3 presents the evidence for the benefits of continuous support in labor. The role of the doula is explained. Women are encouraged to plan for continuous support during labor and to consider including a woman experienced with childbirth among their labor support team.  相似文献   
79.
Focus-on-form English teaching methods are designed to facilitate second-language learners' noticing of target language input, where "noticing" is an acquisitional prerequisite for the comprehension, processing, and eventual integration of new grammatical knowledge. While primarily designed for teaching hearing second-language learners, many focus-on-form methods lend themselves to visual presentation. This article reports the results of classroom research on the visually based implementation of focus-on-form methods with deaf college students learning English. Two of 3 groups of deaf students received focus-on-form instruction during a 10-week remedial grammar course; a third control group received grammatical instruction that did not involve focus-on-form methods. The 2 experimental groups exhibited significantly greater improvement in English grammatical knowledge relative to the control group. These results validate the efficacy of visually based focus-on-form English instruction for deaf students of English and set the stage for the continual search for innovative and effective English teaching methodologies.  相似文献   
80.
Brix weight per stool (BW) of sugarcane is a complex trait, which is the final product of a combination of many components. Diallel cross experiments were conducted during a period of two years for BW and its five component traits, including stalk diameter (SD), stalk length (SL), stalk number (SN), stalk weight (SW), and brix scale (BS) of sugarcane. Phenotypic data of all the six traits were analyzed by mixed linear model and their phenotype variances were portioned into additive (A),dominance (D), additive×environment interaction (AE) and dominance×environment interaction (DE) effects, and the correlations of A, D, AE and DE effects between BW and its components were estimated. Conditional analysis was employed to investigate the contribution of the components traits to the variances of A, D, AE and DE effects of BW. It was observed that the heritabilities of BW were significantly attributed to A, D and DE by 23.9%, 30.9% and 28.5%, respectively. The variance of A effect for BW was significantly affected by SL, SN and BS by 25.3%, 93.7% and 17.4%, respectively. The variances of D and DE effects for BW were also significantly influenced by all the five components by 5.1%~85.5%. These determinants might be helpful in sugarcane breeding and provide valuable information for multiple-trait improvement of BW.  相似文献   
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