全文获取类型
收费全文 | 39篇 |
免费 | 1篇 |
专业分类
化学 | 31篇 |
数学 | 4篇 |
物理学 | 5篇 |
出版年
2020年 | 1篇 |
2019年 | 1篇 |
2018年 | 1篇 |
2016年 | 2篇 |
2015年 | 1篇 |
2014年 | 1篇 |
2012年 | 1篇 |
2011年 | 1篇 |
2008年 | 1篇 |
2007年 | 1篇 |
2005年 | 2篇 |
2004年 | 5篇 |
2002年 | 1篇 |
2000年 | 1篇 |
1999年 | 1篇 |
1998年 | 1篇 |
1995年 | 2篇 |
1987年 | 1篇 |
1984年 | 1篇 |
1983年 | 1篇 |
1982年 | 1篇 |
1981年 | 1篇 |
1978年 | 3篇 |
1977年 | 1篇 |
1976年 | 1篇 |
1975年 | 2篇 |
1973年 | 1篇 |
1972年 | 1篇 |
1971年 | 1篇 |
1970年 | 1篇 |
排序方式: 共有40条查询结果,搜索用时 46 毫秒
1.
J. H. Fairhurst 《The Journal of the Operational Research Society》1972,23(2):165-176
Delays at machines have effects on the timing of input costs as well as on the delivery time of the product. Here we examine a simple model which combines both these effects and represents the inventory decision as a rate of return distribution for each element being produced. A useful concept of equivalent money leadtime is introduced and under simple assumptions is employed to produce the above rate of return distribution. The calculation procedure is indicated but this does not appear to be simple, particularly for joint distributions of stage delays. Finally two sets of simulated results are included to demonstrate the convergence of the two cases (captive and non-captive) as the reorder level is increased. 相似文献
2.
3.
4.
G. G. Jayson T. A. Lawless D. Fairhurst 《Journal of Radioanalytical and Nuclear Chemistry》1981,64(1-2):327-335
A study has been made on the effect of pH upon the equilibrium adsorption capacity of triethyl phosphate, dimethyl phosphate
and orthophosphate on to activated carbon cloth. It is shown that for molecular phosphates no dependence upon pH exists, whilst
the adsorption of ionic phosphates exhibit a strong pH dependence. These adsorption trends may be explained in terms of pKa
values, ionic strength and the surface charge of the activated carbon cloth is aqueous solution. 相似文献
5.
Morris RH Bencsik M Nestle N Galvosas P Fairhurst D Vangala A Perrie Y McHale G 《Journal of magnetic resonance (San Diego, Calif. : 1997)》2008,193(2):159-167
MRI of fluids containing lipid coated microbubbles has been shown to be an effective tool for measuring the local fluid pressure. However, the intrinsically buoyant nature of these microbubbles precludes lengthy measurements due to their vertical migration under gravity and pressure-induced coalescence. A novel preparation is presented which is shown to minimize both these effects for at least 25 min. By using a 2% polysaccharide gel base with a small concentration of glycerol and 1,2-distearoyl-sn-glycero-3-phosphocholine coated gas microbubbles, MR measurements are made for pressures between 0.95 and 1.44 bar. The signal drifts due to migration and amalgamation are shown to be minimized for such an experiment whilst yielding very high NMR sensitivities up to 38% signal change per bar. 相似文献
6.
A simple method is described for the determination of selenium in human tissues without the use of perchloric acid. Digestion with nitric and sulphuric acids is followed by hydride generation and atomic absorption spectrometry. Results for NBS bovine liver and IAEA horse kidney reference materials were in good agreement with assigned concentrations, as was also achieved with the perchloric acid digestion. Recovery of added selenium was >90%, and the relative standard deviation was 5.5% for within-batch and 6.9% for between-batch analyses. The values of selenium in heart tissue were 0.9–1.3 μg g?1 dry weight. 相似文献
7.
The preparation of the η4-4-2,3,5,6-tetramethyl-1,4-benzoquinonecomplex [CO(C5Me5)(C10H12O2)] (I) is reported. Complex I undergoesreversible protonation to yield the 2-6-η-4-hydroxy-1-oxo-2,3,5,6-tetramethylcyclohexadienyl complex [Co(C5Me5)(C10H13O2)BF4 (II) and diprotonation to yield the η6-6-1,4-dihydroxy-2,3,5,6-tetramethylbenzene complex [Co(C5Me5)(C10H14O2)] (BF4)2 (III). Methylation of complex I with MeI/AgPF6 gives the 2---6-η-4-methoxy-1-oxo-2,3,5,6-tetramethylcyclohexadienyl complex [Co(C5Me5)(C11H15O2])PF6 (IV). In trifluoroacetic acid solution complex IV is protonated to form the η6-1-hydroxy-4-methoxy-2,3,5,6-tetramethylbenzene cation [Co(C5Me5)-(C11H16O2)]2+ 相似文献
8.
Razavet M Borg SJ George SJ Best SP Fairhurst SA Pickett CJ 《Chemical communications (Cambridge, England)》2002,(7):700-701
Iron(I) in biology?: one-electron oxidation of an (Fe(I)-Fe(I)) carbonyl cyanide precursor bearing a proximal thioether group leads to an (Fe(I)-Fe(II)) bridging carbonyl transient with spectral features similar to the di-iron sub-site of the CO inhibited paramagnetic centre of all-iron hydrogenase. 相似文献
9.
Fairhurst D Rowell RL Monahan IM Key S Stieh D McNeil-Watson F Morfesis A Mitchnick M Shattock RA 《Langmuir : the ACS journal of surfaces and colloids》2007,23(5):2680-2687
New measurements of the dependence of the surface charge on the pH and electrolyte concentration for three living human white blood cell lines that are the principal targets of the HIV-1 virus are reported. Comparison of the electrophoretic fingerprint (EF) pattern, especially the line of zero mobility, with that of reference colloids establishes the separate individual identities and shows that all three exhibit a zwitterionic surface. With the EF results as a guide, preliminary biological infectivity measurements showed that small polyvalent cations modulate the negative charge on the T-cell surface in a way that strongly affects the infection kinetics. H9 cells were exposed to an infectious virus (X4), and the data showed that HIV interaction with target cells is enhanced by physiological fluids. The nondestructive methodology described is generally applicable to characterization of the surface charge and determination of the colloidal stability of any aqueous charged colloidal system without reference to any model of the double layer. 相似文献