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31.
《Optimization》2012,61(3):577-595
We prove the Fritz John and Kuhn-Tucker necessary optimality conditions for vector optimization problems involving multifunctions and parameters under relaxed assumptions. 相似文献
32.
34.
Robert P. Crease 《Physics in Perspective (PIP)》2005,7(3):330-376
The story of ISABELLE, a colliding-beam accelerator conceived in 1971, officially approved in 1978, partially constructed,
and terminated in 1983, is an important episode in the history of post-World War II science in the United States.The events
surrounding its planning, construction, and termination reveal much about the ambitions, strategies, and tensions of American
high-energy physicists, their collaborations and rivalries, and the difficulties of funding and constructing a large scientific
facility in the age of Big Science. In this article, the first of two parts, I cover the period up to the beginning of construction
in 1978. I place ISABELLE in the context of the early history of colliders, outline the physics goals that motivated the machine,
and describe the research and motivations behind its innovative but ultimately problematic superconducting magnet design.
I cover the key technological and administrative steps that the laboratory took to get the project underway and steer it past
several review committees. I also treat some of the conflicts within the laboratory, and between Brookhaven and other laboratories,
especially Fermilab, that hampered the project.
Robert P. Crease is a Professor in the Department of Philosophy of Stony Brook University in Stony Brook, New York, and historian
at Brookhaven National Laboratory. 相似文献
35.
Irene Drelichman Ricardo G. Durán 《Journal of Mathematical Analysis and Applications》2008,347(1):286-293
In this paper we prove that if Ω∈Rn is a bounded John domain, the following weighted Poincaré-type inequality holds:
36.
Infusion-induced changes in the phenolics, antioxidant and colour propeties of St John’s wort (genus, Hypericum; specie, Hypericum perforatum L.) teas were studied for the first time. SJW teas prepared as three different infusions and coded as three (3?min), six (6?min) and twelve minutes (12?min). Investigation of phenolic compounds were performed by LC-DAD-ESI-MS/MS. A total of 18 phenolics including six chlorogenic acids, three phenolic acids, seven flavonoids and two naphtodianthrones were detected. It is worth noting that the phenolic profiles of St John’s wort teas were similar. However, the quantities of phenolic compounds individually and totally changed significantly for different infusion times. The highest total concentration was detected in 12?min (60.03?mg/L), followed by 6?min (54.81?mg/L) and 3?min (33.07?mg/L). The main difference for different infusion times was the hyperoside found as the most abundant phenolic only in 3?min samples. However, for 6?min and 12?minin infusions, chlorogenic acid was the most dominant phenolic compound. Similar to phenolics, antioxidant capacity of tea infusions showed an increasing trend with the extension of infusion time. 相似文献
37.
Esters are chemical compounds with many practical uses. The common type of esterification is called the Fischer esterification. Another one is by the action of acid chlorides on alcohols but not with tertiary alcohols. The stable carbenium ions formed from tertiary alcohols favor elimination and the byproduct, hydrogen chloride prevents ester formation. In this new report, palladium inserted ArCOPdCl species reacts with tertiary alcohols and cross-coupling under microwave heating, minimizes the formation of probable carbenium ion, and promotes successful production of highly substituted esters in good to high yields. 相似文献
38.
约翰·爱德华·兰纳-琼斯(1894—1954)是英国杰出的理论化学家。兰纳-琼斯因其在分子结构、原子价和分子间力等方面的研究而闻名,其中最重要的是提出了表达中性原子或分子之间的相互作用的一个简单的数学模型,这个模型被称为兰纳-琼斯势函数(也称L-J势函数或6~12势函数);他是第一个以目前普遍使用的方式使用原子轨道的线性组合来定量描述分子轨道(LCAO MO理论)的人,被称为分子轨道理论的奠基人之一。本文介绍了约翰·爱德华·兰纳-琼斯的生平,并对兰纳-琼斯提出兰纳-琼斯势函数和建立分子轨道的原子轨道线性组合法的过程进行了详细论述。 相似文献
39.
40.
Matthew Trainer 《Physics in Perspective (PIP)》2008,10(2):212-223
In 1905 Lord Kelvin (1824–1907) was awarded the second John Fritz Medal for a lifetime of outstanding achievements in science
and technology. I sketch Kelvin’s life, education, and work in thermodynamics, electrical technology, and instrumentation,
and his role in the laying of the Atlantic cable. I then turn to Kelvin’s four visits to America, in 1876 on the centenary
of the Declaration of Independence of the United States of America; in 1884 when he gave his famous Baltimore Lectures at
The Johns Hopkins University; in 1897 when he visited Niagara Falls for the third time and advised George Westinghouse (1846–1914)
on how to develop its enormous water power for the generation of electricity; and in 1902 when he advised George Eastman (1854–1932)
on the development of the photographic industry.
Written in connection with the Kelvin Centenary Year 2007; see “Celebrating the Life of Lord Kelvin,” University of Glasgow
News Review No. 11 (2007), 4.
Matthew Trainer: Matthew Trainer received his M.Phil. degree in physical sciences at the University of Edinburgh in 1980 and
currently is a laboratory instructor at the University of Glasgow where his research focuses in part on the life and work
of Lord Kelvin. 相似文献