Science reproducibility

Fig. 7.8 Transport of gases through tubes of different lengths and diameters. From Glassblowing for Laboratory Technicians, 2nd ed., Fig. 10.2, by R. Barbour, 1978 by Pergamon Press Ltd. (now Elsevier Science), reproduced with permission.

Photo courtesy of Dr. Pawel Tomaszewski, Institute of Low Temperature and Structure Research, Polish Academy of Sciences. Reproduced with permission. 

Source [HH, p. 1491], Copyright 1980, American Association for the Advancement of Science. Reproduced by permission. 

FIGURE 7.20. (a) A viscous bubble is formed by injecting air in ultra-viscous PDMS it thins down by way of a draining process (b) bursting and death of the bubble recorded with an ultra-high-speed camera. (FVom G. Debregeas, P. G. deGennes, and F. Brochard, in Science, 279, p. 1704 (1998). 2001 American Association for the Advancement of Science. Reproduced by permission.)... 

FIGURE 9.18. lYajectorv of a 1-min water drop impacting a slightly iiiclimxl super-hy[Pg.234]

FIGURE 10.11. Festoon instability. Snapshot of a drop of low-volatlliiy. silicone oil (2-// volume. -liO-g molecular ma.ss). Optical interference can t>e soon at the surface of the ridge forms around the i)erii)hery of the (Iroj) an[Pg.274]

Figure A2.5.26. Molar heat capacity C y of a van der Waals fluid as a fimction of temperature from mean-field theory (dotted line) from crossover theory (frill curve). Reproduced from [29] Kostrowicka Wyczalkowska A, Anisimov M A and Sengers J V 1999 Global crossover equation of state of a van der Waals fluid Fluid Phase Equilibria 158-160 532, figure 4, by pennission of Elsevier Science.

Hansma H G, Vesenka J, Siegerist C, Kelderman G, Morrett H, Sinsheimer R L, Bustamante C, Elings V and Hansma P K 1992 Reproducible imaging and dissection of plasmid DNA under liquid with the atomic force microscope Science 256 1180... 

Figure C2.6.7. Fractal aggregate of gold particles with a = 12 0.7 nm, obtained under DLCA conditions, with = 1.74 (reproduced with pennission from [65]. Copyright 1984 Elsevier Science Publishers B.V).

The scientific method, as mentioned, involves observation and experimentation (research) to discover or establish facts. These are followed by deduction or hypothesis, establishing theories or principles. This sequence, however, may be reversed. The noted twentieth-century philosopher Karl Popper, who also dealt with science, expressed the view that the scientist s work starts not with collection of data (observation) but with selection of a suitable problem (theory). In fact, both of these paths can be involved. vSignificant and sometimes accidental observations can be made without any preconceived idea of a problem or theory and vice versa. The scientist, however, must have a well-prepared, open mind to be able to recognize the significance of such observations and must be able to follow them through. Science always demands rigorous standards of procedure, reproducibility, and open discussion that set reason over irrational belief. 

In the nonclassical ion controversy discussed in Chapter 9, there was never any question on either side of the debate about the validity of the observed data, only about their interpretation. Had any of the experimental data been questioned or found to be incorrect, this would have been soon found out because so many people repeated and rechecked the data. This is the strength of science (in contrast to politics, economics, etc.), i.e., that we deal with reproducible experimental observation and data. Nevertheless, interpretation can still result in heated discussions or controversies, but science eventually will sort these out based on new results and data. 

The number and kind of defects in a given specimen, as well as the crystal habit and with it the proportion of different crystal faces exposed, will in general depend in considerable degree on the details of preparation. The production of a standard sample of a given chemical substance, having reproducible adsorptive behaviour, remains therefore as much an art as a science. 

Catalyst preparation is more an art than a science. Many reported catalyst preparations omit important details and are difficult to reproduce exacdy, and this has hindered the development of catalysis as a quantitative science. However, the art is developing into a science and there are now many examples of catalysts synthesi2ed in various laboratories that have neady the same physical and catalytic properties. 

Fig. 19. Comparison of undeveloped grain (left) exposed and developed grain (center) and silver of a single unexposed grain that has transferred and developed to form a positive image deposit (97). Reproduced with permission of IS T, the Society for Imaging Science and Technology.

Figures 30 (c) and 30 (d) reproduced courtesy of IS T, the Society for Imaging Science and Technology.

The molecular and liquid properties of water have been subjects of intensive research in the field of molecular science. Most theoretical approaches, including molecular simulation and integral equation methods, have relied on the effective potential, which was determined empirically or semiempirically with the aid of ab initio MO calculations for isolated molecules. The potential parameters so determined from the ab initio MO in vacuum should have been readjusted so as to reproduce experimental observables in solutions. An obvious problem in such a way of determining molecular parameters is that it requires the reevaluation of the parameters whenever the thermodynamic conditions such as temperature and pressure are changed, because the effective potentials are state properties. 

Reproduced, with minor revisions in the light of data now available, from chapter on Tlie Glass Transition, Melting Point and Structure by the author in Polymer Science edited by Professor A, D. Jenkins. with permission of Nonh Holland Publishing Company. 

Fig. 2.8. Equivalent benzyl CHj protons in 1-benzyl-cis-2,6-dimethylpiperidine compared with nonequivalent protons in the tmns isomer. [Reproduced from Tetrahedron 21 2015 (1965) by permission of Elsevier Science.]...

A. Potential energy of substituted acetaldehydes as a iunction of the OCCR angle, relative to 4k energy of the syn (ZOCCR = 0°) rotamer isolated molecules. [Reproduced with permission of Ejsevier Science Publishing.]... 

Fig. 9.6. Crystal structure of 9,10-diphenylbicyclo[6.2.0]deca-l,3,5,7,9-pentaene. (Reproduced from Ref. 146 by permission from Elsevier Science.)...

Fig. 21. High-resolution XPS spectra of PMMA spin-coated onto (a) silicon and (b,c) iron. The C(ls) spectnim of PMMA on silicon was explained by four components but an additional component was needed to explain the C(ls) spectrum of PMMA on iron. Reproduced by permission of Gordon and Breach Science Publishers from Ref. [24].

Fig. 23. C(ls) and 0(ls) spectra of polyphenylene ether before (hottom) and after (top) deposition of 0.4 nm of chromium. Reproduced hy permission of Gordon and Breach Science Publishers from Ref. [28].

Fig. 30. C(ls) XPS spectra of high-density polyethylene before and after flame treatment. Reproduced by permission of VNU Science Press B.V. from Ref. [8].

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