全文获取类型
收费全文 | 168篇 |
免费 | 2篇 |
专业分类
化学 | 143篇 |
晶体学 | 1篇 |
物理学 | 26篇 |
出版年
2013年 | 2篇 |
2011年 | 2篇 |
2009年 | 2篇 |
2007年 | 2篇 |
2006年 | 3篇 |
2004年 | 3篇 |
2002年 | 2篇 |
2001年 | 2篇 |
2000年 | 4篇 |
1999年 | 2篇 |
1998年 | 2篇 |
1995年 | 1篇 |
1994年 | 4篇 |
1993年 | 3篇 |
1992年 | 2篇 |
1991年 | 1篇 |
1989年 | 1篇 |
1987年 | 1篇 |
1986年 | 2篇 |
1983年 | 1篇 |
1981年 | 1篇 |
1980年 | 1篇 |
1979年 | 1篇 |
1978年 | 3篇 |
1977年 | 5篇 |
1976年 | 10篇 |
1975年 | 4篇 |
1974年 | 5篇 |
1973年 | 1篇 |
1972年 | 1篇 |
1970年 | 6篇 |
1969年 | 3篇 |
1968年 | 10篇 |
1967年 | 5篇 |
1966年 | 3篇 |
1965年 | 4篇 |
1964年 | 3篇 |
1963年 | 3篇 |
1962年 | 4篇 |
1961年 | 3篇 |
1959年 | 2篇 |
1958年 | 5篇 |
1957年 | 2篇 |
1956年 | 6篇 |
1955年 | 5篇 |
1954年 | 4篇 |
1953年 | 7篇 |
1952年 | 3篇 |
1951年 | 6篇 |
1949年 | 2篇 |
排序方式: 共有170条查询结果,搜索用时 109 毫秒
1.
Characterization of autocatalytic decomposition reactions is important
for the safe handling and storage of energetic materials. Isothermal differential
scanning calorimetry (DSC) has been widely used to detect autocatalytic decomposition
of energetic materials. However, isothermal DSC tests are time consuming and
the choice of experimental temperature is crucial. This paper shows that an
automatic pressure tracking calorimeter (APTAC) can be a reliable and efficient
screening tool for the identification of autocatalytic decomposition behavior
of energetic materials.
Hydroxylamine nitrate (HAN) is an important
member of the hydroxylamine family. High concentrations of HAN are used as
liquid propellants, and low concentrations of HAN are used primarily in the
nuclear industry for decontamination of equipment. Because of its instability
and autocatalytic decomposition behavior, HAN has been involved in several
incidents. 相似文献
2.
Various procedures were examined for the determination of organic hydroxyl groups. Conventional acetylation methods could not be used on the submicro scale, but the spectrophotometric method based on esterification with 3,5-dinitrobenzoyl chloride followed by extraction of the ester and colour development with alkaline acetone proved reasonably satisfactory for aliphatic alcohols. Acidic hydroxyl groups e.g. in phenolic compounds, were titrated accurately with 0.01 M tetrabutylammonium hydroxide in benzene-methanol solution in a pyridine medium ; visual end-points or potentiometricend-points with glass-silver or glass-in-stream platinum electrode pairs were used depending on the strength of the acidic group. Some differentiating titrations were possible. A general submicro bromination method for phenols was not feasible. 相似文献
3.
4.
Thiocyanate (2.7-90 mug) and thiosulphate (4.5-90 mug) ions are oxidized by iodine in alkaline media to sulphate ions. After acidification, the excess of iodine is extracted into chloroform, and the iodide ions formed in the redox reaction subjected to an amplification reaction. Either a titrimetric or a spectrophotometric finish may be used. Each thiocyanate and thiosulphate ion results in the ultimate production of 19 and 24 iodine molecules, respectively. 相似文献
5.
An investigation of the MECA behaviour of sulphate, sulphite, metabisulphite, peroxodisulphate, thiocyanate, thiosulphate and sulphide ions, has shown that ng amounts of these anions may be determined in samples of a few μl. Metal ion interferences in the determination of sulphate and sulphite are removed by addition of phosphoric acid. 相似文献
6.
R. Belcher J. R. Majer W. I. Stephen I. J. Thomson P. C. Uden 《Analytica chimica acta》1970,50(3):423-431
Preparative details for perfluoroalkanoylpivalylmethanes and their lead chelates are given. Thermal analysis, gas chromatography and mass spectral studies all indicate high thermal stability, but strong column interaction makes successful quantitative gas chromatography difficult. The integrated ion-current technique is applied to determine lead heptafluorobutanoylpivalylmethanate in the range 10-9–10-7 g of lead, but a lower detection limit of ca. 10-14 g is indicated. 相似文献
7.
Cadmium salts give an intense cadmium atomic emission in the MECA cavity in a hydrogen-nitrogen-air flame. When a carbon or stainless steel cavity is used, 10–120 ng of cadmium in 5-μl samples can be determined. In the presence of sulphuric acid, anionic interferences are removed. Of the cations, only Fe(III), Cr(III), Mg and Sn(II) interfere seriously. 相似文献
8.
9.
10.