Direct Current Magnetic Field and Electromagnetic FieldEffects on the pH and Oxidation-Reduction Potential

Equilibration Rates of Water. 1. Purified Water

Masumi Yamashita,*,† Chris Duffield,‡ and William A. Tiller‡

Department of Geophysics and Department of Materials Science and Engineering,Stanford University, Stanford, California 94305

Received March 24, 2003. In Final Form: April 25, 2003

Effects of low level magnetic and electromagnetic fields (below B ∼ 100 mG for ac magnetic field, andbelow B ∼ 1000 G for static magnetic field), on purified water that is in the process of equilibration, wereinvestigated. The pH and oxidation-reduction potential (ORP) of distilled and deionized water, previouslystored for air equilibration, were measured after exposure to magnetic fields (ac and dc) of different strengths.Readings showed slow and large fluctuations (∼0.05-0.1 pH unit, ∼60 mV for ORP) during the firstseveral hours. These readings looked deceptively stable due to the extreme slowness of the fluctuations.When readings were taken beyond this period, for days, the pH and ORP generally changed slowly towardequilibrium values in a quasi-linear fashion. They changed faster, on average, in those samples that hadbeen exposed to higher magnetic fields. Readings in water samples often “got stuck”, remaining unchangedover an extended period before starting to change again, when stored for equilibration with air and measuredin a mu-metal shield, where the ac magnetic flux was ∼0 mG (zero field). These results indicate that, toaccurately evaluate the effects of weak magnetic fields on water, subtle experimental conditions such asdifferential field conditions produced by common lab devices and procedures, and background lab fields,cannot be ignored. Moreover, extending measurements beyond several hours may be essential to reliablyobserve the presence or absence of these effects.

Introduction

It is well-known that water exhibits a wide range ofanomalous behaviors with respect to its various materialproperties.1-4 The literature on the subject is vast andoften confusing, covering a variety of spatial size scalesas well as temporal response times. The spatial size scalescan be conveniently divided into three categories: (1)molecular level properties, including water clusters, withthe system considered to be “effective” single phase waterand homogeneous on a size scale of 10-7 to 10-6 cm, (2)two-phase or polyphase water properties associated witheither classical critical point phenomena or cooperativeinternal electromagnetic (EM) mode interaction phenom-ena, with this size scale being treated as an “effective”single phase and homogeneous on a size scale of <10-5 to10-4 cm, and (3) a heterogeneous system of the foregoing,plus foreign bodies such as H2nOn water clusters, colloids,long chain molecules, microscopic gas bubbles, spacecharge layers, and so forth.

Temporal sizescale changes forphenomena incategories1 and 2 run from picoseconds to seconds, while for category3 they can run from seconds to days. The confusingplethora of experimental data on water is somewhatconfirmed by the remarkable fact that more than two dozenwater potential energy functions are in regular use todayfor various computer simulation activities.5

The importance of category 3 above is that, in an aqueouselectrolyte, these microscopic moieties interact in uniqueways with the ambient electric, magnetic, and EM fieldsso as to move them in certain directions in their macro-scopicenvironment. In turn, thisproduces: (a)macroscopicspatial concentration changes in these moieties, leadingto macroscopic property variations in overall solution, (b)activation of local thermodynamic forces to recreate, atsome kinetically limited rate, the equilibrium populationof such moieties in the regions dynamically vacated, and(c) activation of such forces to agglomerate or coagulatesuch moieties in the overly enriched regions of themacroscopic solution (at rates determined by the uniquekinetics of these processes). Most of this is straightforwardphysical chemistry of many interacting processes whichhave not been recognized by many experimenters.

In addition to the foregoing, three environmentalinfluences that have not been carefully controlled byvarious experimenters during their studies are (1) dcmagnetic field and EM field intensities and gradients, (2)convection mode and intensity, and (3) lighting mode andintensity. All three of these environmental influencesappear to impact the experimental results of various waterstudies, and are in need of careful investigation.6-12 Inthis series of papers, we largely focus on item 1 and a little

* To whom correspondence should be addressed. E-mail: masmi@pangea.stanford.edu. Telephone: (650) 322-4739.

† Department of Geophysics.‡ Department of Materials Science and Engineering.(1) WatersA Comprehensive Treatise; Franks, F., Ed.; Plenum: New

York, 1972-1982; Vols. 1-7.(2) Stillinger, F. H. Science 1980, 209, 451-457.(3) Water and Aqueous Solutions-Structure, Thermodynamics, and

Transport Processes; Home, R. A., Ed.; Wiley: New York, 1972.(4) Mishima, O.; Stanley, H. E. Nature 1998, 396, 329-335.(5) Brodsky, A. Chem. Phys. Lett. 1996, 261, 563-568.

(6) Higashitani, K.; Oshitani, J. J. Surf. Sci. Soc. Jpn. 1999, 20,764-769.

(7) Oshitani, J.; Yamada, D.; Miyahara, M,; Higashitani, K. J. ColloidInterface Sci. 1996, 210, 1-7.

(8) Qi, J.; Wakayama, N. I. Mater. Trans., JIM 2000, 41, 970-975.(9) Waskaas, M. J. Phys. Chem. 1993, 97, 6470-6476.(10) Huang, J.; Gray, D. D.; Edwards, B. F. Phys. Rev. E 1998, 58,

5164-5167.(11) Hara, M.; Kondo, T.; Komoda, M.; Ikeda, S.; Shinohara, K.;

Tanaka, A.; Kondo, J, N.; Domen, K. Chem. Commun. 1998, 3, 357-358.

(12) Ikeda, S.; Takata, T.; Komoda, M.; Hara, M.; Kondo, J. N.; Domen,K.; Tanaka, A.; Hosono, H.; Kawazoe, H. Phys. Chem., Chem. Phys.1999, 1, 4485-4491.

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10.1021/la034506h CCC: $25.00 © 2003 American Chemical SocietyPublished on Web 07/18/2003

of item 2 above, using pH and oxidation-reductionpotential (ORP) measurements as our experimentalprobes.

Part 1 of this paper restricts itself to the study of purified(distilled and deionized) water in equilibrium with air,without added salts. Results indicate that both H and ∇Hinfluence the kinetics of equilibration, that the neededtime scale for such equilibration is long, and that enhancedmeasurement precision is needed. Part 2 describesperturbing effects of some solutes, ambient stirring, andlight. The tentative theoretical hypothesis to account forthese environmental magnetic effects is that a diamag-netophoresis force is operating in the water solution toalter the kinetics of the equilibration process. Underscor-ing this conclusion is that, in a zero H-field environment,water proceeds toward equilibrium at an extremely slowrate and appears to get stuck for a long time in a seriesof intermediate metastable states.

Experimental ProceduresIn similar studies, and in chemical documents in general, it

is often the ultimate equilibrium values or states that arereported. Water encountered in nature, however, is rarely atchemical equilibrium, nor is it being forced to stay at equilibrium.Observations of the effects of electromagnetic or magnetic fieldson water in its progress toward equilibrium should enhance ourpicture of their interactions in nature. Resultant data may bemore directly useful in many fields, such as engineering andenvironmental studies. There is a risk, naturally, that someuncontrolled factors may vary between sample and controllocations, causing a difference in their response. Multiplemeasurements are necessary to average out such unwantedeffects.

In this study, water was allowed to move toward stableequilibriumwithairwithminimumintervention,while conditionsother than magnetic exposure levels were kept as comparable aspossible between sample and control. Ten or more measurementswere taken for each experiment.

Sample Preparation. Distilled water and deionized water(ASTM type I water) were stored in loosely lidded lab-gradepolypropylene jars for at least 1 day before experiments, forequilibration with air, until their pH reached the theoreticalvalue (about 5.7) for purified water saturated with CO2 at roomtemperature and normal atmospheric pressure. At this point,further pH change was slower than 0.005 pH units per hour.After this aging process, the same volume (250-300 mL) of waterwas poured into each sample container (lab grade polypropyleneand acrylic jars with screwed-on lid). No salts were added to thewater sample prior to the measurement. (Such purified watercannot be considered to be pure by today’s standards, as it containsthree oxygen isotopes (oxygen-16, -17, and -18), several dissolvedgases, and ortho and para isomers of water in an ortho/para ratiothat may vary from ∼10:1 to 3:1, depending upon conditions.)

Stirring. In experiments with stirring, a stirrer with a 55 cmfiberglass shaft and a 3 cm nonmagnetic stirring rod on the endwas used. When the stirrer was turned on, the ac magnetic fluxat the location of the water sample changed by less than 0.2 mG.So the effects of the ac field generated by the stirrer’s motor wereconsidered to be negligible.

Temperature. The temperature dependence of glass pHelectrodes was corrected by the use of temperature compensationprobes. The temperature of the water sample was allowed toshift naturally with room temperature. The air temperature atdifferent sample locations in the lab usually differed by <0.2 °C.The water temperature could fluctuate up to 2 °C during thefirst few hours of the measurement. Beyond this initial period,slow, diurnal change in water temperature took place, identicalin pattern and amplitude in all water samples.

Measurement Technique. Measurement of pH and ORPwas carried out with six meters that had an input impedance of>1012 Ω (Denver Instruments pH, ISE conductivity meter, model225, and model 250 versions 1 and 2; Accumet model 150 titrationcontroller; Accumet AR50 dual channel pH/ion/conductivitymeter, versions 1 and 2). Data values were sent from the meters

to a PC via RS-232. For pH, Ross combination electrodes (Orion8102) and, for ORP, platinum electrodes (Orion 96-78) were used.With careful grounding, all measurements were conducted eitherinside a Faraday cage inside or a mu-metal cylinder. Backgroundnoise was (0.002 pH unit for pH and (0.3 mV for ORPmeasurement.

Calibration. The pH probes were calibrated using Orion purewater test kit buffers, pH ) 4.10 and 6.98 (both (0.03 at 25 °C),for experiments with low ionic strength solutions having aconductivity of less than 100 µS/cm. KCl solution, supplied withthe Orion pure water test kit to adjust the ionic strength of “pure”water samples, was not added. For other solutions, standardbuffers were used: Orion pH ) 4.01, VWR pH ) 7.0, and VWRpH ) 10.0 (all (0.01 at 25 °C). The calibration slope window waskept at 99.5-100.5%. The ORP probes were calibrated relativeto each other. (Until recently, pH electrodes were notoriouslyinaccurate in solutions of low ionic strength. Manufacturers todayhave corrected this deficiency, and special electrodes are availablefor such solutions.)

A brief description of the procedures developed to enhance themeasurement accuracy sufficient for long-term pH and ORPmeasurements is given in the Supporting Information section ofthis article.

Results

1.Short/LongTime-ScaleBehavior. For twosamplesof distilled water, A and B, Figure 1 illustrates typicalshort-time to long-time, respectively, pH behavior. Asdistinct from background noise, one typically notes twotypes of fluctuations for the first few hours after the probeshave been in place: (i) rapid (τ ∼ 1-3 s), small-amplitude(∼0.01-0.03 pH units or ∼1-3 mV for ORP) fluctuationsthat subside within a few minutes, and (ii) slow (τ ∼ 10-30 min), large-amplitude (∼0.05-0.1 pH unit or ∼60 mVfor ORP) fluctuations that last for several hours. Readingsduring the first few minutes were occasionally stablewithout fluctuations of type i; but type ii fluctuations, oflonger period, were almost always observed. The pHreadings from two fault-free probes in different samplescould have a large difference at one moment and nodifference 30 min later. ORP, on the other hand, tendedto fluctuate more or less simultaneously in the samedirection for samples from a given batch of distilled water.A typical example of this behavior can be seen in Figure2. These slow/large-amplitude fluctuations occurred in-dependently of temperature.

It is important to note in Figure lc the long-time linearpH slope regime that developed for the two samples. Inthis example, both samples were stored in similar condi-tions, and both developed nearly the same slope andintercept. This linear slope regime, at long times, is verycharacteristic for this type of water. A very similar typeof behavior was observed with ORP measurements, thatis, fluctuations at short time and evolution to a constantslope regime after ∼5-10 h. For both pH and ORP, thetwo parameters, slope and intercept, provided a valuabletool for reliably comparing, at long time, small differencesbetween samples that were exposed to different environ-mental conditions before the experiment began. Reliabilityof measurements leading to slopes and intercepts wasregularly verified by shaking the sample to homogenizeit, or by using a second probe in a different region of thesame sample. Also, electrode recalibration after the long-time measurements showed that very little absolutemeasurement error had occurred.

2. Zero versus Ambient H-Field Exposure. For twosamples from the same batch of deionized water, Figure2 illustrates the short-time and long-time behavior asinfluenced by either an H ) 0 environment (aged for 5days in a long mu-metal cylinder) or an ambient laboratoryH-field (aged for 5 days in an electrically grounded Faraday

6852 Langmuir, Vol. 19, No. 17, 2003 Yamashita et al.

cage), during premeasurement storage. The ORP valuesfor these two samples differed by less than 2 mV at thefourth minute, but their intercept differed by ∼40 mV inthe long-term measurement. The fitting equations inFigure 2b are for the time interval between the 25th and37th hours. The chart reveals that, after 40 h, these twosamples of water were still a very long way from reachinga possible equilibrium condition. From the slope values,this might require thousands of hours.

In Figure 3, a pH comparison is made for two samplesof deionized water from the same batch, but measured ina Faraday cage with an ambient H-field, versus two othersamples from this same batch measured in the mu-metalcylinder. One notes that, although the ambient fieldsamples approach a common value after 14 h, the zerofield samples do not. In the zero H-field case, the pHappears to stay locked in intermediate states for longperiods, without change, before moving on toward someindividual end states for this 14 h time period.

3. Static Fluid/dc Magnetic Effect. To measure theeffects of a static magnetic field on static water, pH was

measured for 20 h for samples of distilled water that weresimultaneously exposed to a static magnetic field. A barmagnet of about 1000 G was attached to the bottom wallof one sample container, as in Figure 4. Water from thesame batch but without a magnet served as a control, and10 individual comparison tests were run. Separate ex-periments were taken over a period of 2 months tominimize data bias from varying distilled water qualityand other uncontrolled factors. Large variation betweeneach run, as indicated by the standard deviation, supportsthis approach. Table 1 lists the slope mean, median, andrange with standard deviation (STD). All the statistics inthis work were calculated using the student’s t-test for2-tailed small sample analysis unless otherwise noted.

From these data it seems clear that the presence of thisdc magnet caused the rate of pH change with time toincrease. The action of this H-field on pH evolution seemedto end with the abrupt removal of the magnet.

4. Moving Fluid/dc Magnet Effect. In these experi-ments pH was measured after the water was stirred whilebeing exposed to a static magnetic field for 3 min. The pHwas also measured simultaneously for a standing un-stirred water sample, to get a baseline, and for stirredwater without magnetic exposure, to see any change inpH caused by the stirring alone. Separate measurementswere taken over a period of months.

The test water was stirred for 3 min between twopermanent magnets (1000 G each) with opposing poles.Figure 5 illustrates the dual dc magnet configuration,relative to the vessel of distilled water, as used for thisset of experiments. Aluminum foil was placed around thestirrer to minimize contamination by dust. The control(same water batch, but no magnets) was also stirred forexactly 3 min. The samples remained in a Faraday cage

Figure 1. (a) Typical pH measurement, first 5 min. Apparent“stability” after 3 min of fluctuation. (Distilled water, 2 samples,same batch and conditions.) Meter: Denver 225 for Figures1a-c. (b) Same pH measurement series as Figure 1a, first 5 h.Apparent “stability” of Figure 1a actually was the start of slow,large amplitude chaotic fluctuations. (c) Same pH measurementseries as Figures 1a and 1b, first 2 days. Ordered linear pattern,and similarity of samples, appear on this long-time scale.

Figure 2. (a) ORP of water previously stored in differentconditions, first 4 min. Both readings were stable and decep-tively similar in short term. (Deionized water stored 5 days inambient field and zero field.) Meter: Denver 225 for Figures2a and 2b. (b) ORP of water, same samples as Figure 2a, first40 h. Difference between intercepts of long-time linear trendsmay reflect different sample storage conditions.

pH and ORP Equilibration Rates of Water Langmuir, Vol. 19, No. 17, 2003 6853

during stirring. However, the lid was taken off to let thelong stirring shaft through. During stirring, the pHelectrodes were hung with just their tips immersed inwater from the same batch in another container, to preventdrying. The magnets were left on the container for a fewminutes after stirring, during which pH measurementbegan. Table 2 provides slope mean, median, and rangefor these 10 comparisons. One can clearly see that, for pHslope, (stirring plus magnets) > (stirring alone) > (un-stirred, no magnets). The mean pH slope, with this magnet

configuration, was ∼1.6 times larger than that withstirring only.

Figure 6 is provided to give a more detailed picture ofone set of the raw pH data from which Table 2 was derived.Sample A was stirred with magnets present, while sampleB was stirred without magnets. At about the 18 h point,both measurement probes were placed in sample A, and∼2 h later, both were placed in sample B. This tended toconfirm the reliability of the probe measurements.

5. 60 Hz EM Fields versus the H ) 0 Condition. Inthis set of experiments, the pH was measured both duringand after exposure to low intensity ac magnetic fields(“high field” (HF) with B values of ∼40-120 mG, “ambientfield” (AF) with B values of ∼3-9 mG, and “zero field”(ZF) with B value of ∼0 mG). Two ac adapters, of the typecommonly found in residences and work places, were usedas the 60 Hz source, with the field intensity beingmeasured by a triaxial ac magnetic flux meter. In theseexperiments, the samples were first stored at their fieldexposure locations for 1-7 days, and then relocated to anarea where the magnetic flux was at ambient level (∼3-5mG), for measurement.

For 12 sample pairs of deionized water from the samebatch, Table 3 provides ORP slope mean, median, andrange values for these 12 sample pairs. One notes that,on average, the ORP evolution rate for AF conditions wasabout twice that for ZF. Figure 7 provides an exampletime course for ORP evolution in these two field categories.Note the very long metastable region (between hours 45and 75) for the ZF case. In the data on aqueous solutions,to be presented in Part 2,13 the HF case provided stillhigher slopes than the AF case, for comparable evolutiontimes, and appeared to asymptotically move toward zeroslope after about 5 days. The temperatures of the watersamples in zero field and ambient field shifted in closeparallel, so the temperature shift was apparently not thedirect cause of the differential behavior of their ORPvalues.

When these water samples were abruptly stirred in theZF condition compared to the AF condition, there was

(13) Mendenhall, W.; Beaver, R. J. Introduction to probability andstatistics, 8th ed.; PWS-Kent: Boston, 1991; Chapter 9, pp 322-391.

(14) Yamashita, M.; Duffield, C.; Tiller, W. A. DC magnetic field andelectromagnetic field effects on the pH and ORP equilibration rates ofwater; Part II: Aqueous Solutions. In preparation.

Table 1. pH Slope Variation with Static Magnetic Fielda

exposure condition mean slope (pH/h) median slope (pH/h) slope range (pH/h)

with magnet 0.0063 (STD ) 0.002) 0.0057 0.002-0.0098without magnet 0.0048 (STD ) 0.003) 0.0047 0.000-0.0086ratio 1.3 (STD ) 17) 1.2 0.68-55

a p-value < 0.10. Ten samples of unstirred distilled water for each exposure condition.

Figure 3. (a) pH measured in ambient magnetic field. (Twodeionized water samples measured in Faraday cage.) Meter:Denver 225. (b) pH measured in zero magnetic field. In zerofield, pH evolved more slowly, and often stabilized for an houror more at values where water did not stabilize in the ambientfield. (Two samples, same water batch as Figure 3a, measuredin magnetically shielded cylinder. Meter: AR 50. The fourmeasurements shown in 3a and 3b were collected simulta-neously.

Figure 4. Water vessel and magnet placement for static-water/dc-field experiments.

Figure 5. Water vessel and magnet placement for stirred-water/dc-field experiments. The lid was removed, and the foilcover added during stirring with nonmagnetic stirring bar.

6854 Langmuir, Vol. 19, No. 17, 2003 Yamashita et al.

generally (i) a larger immediate change in pH or ORPlevel for the ZF compared to the AF, and (ii) a slowertransition back to a new, or the same, time-evolution curvefor the ZF compared to the AF. This behavior can be readilyseen in Figure 8. When one compared two samples fromthe same batch in the ZF environment with stirring, buteither with or without two dc magnets attached to thevessel as in Figure 5, a significantly larger pH and ORPslope always developed for the attached-magnets case.

Discussion

Several rather remarkable insights concerning waterarise from this fairly straightforward and fairly low-techstudy. The first is that, even with highly purified water

(approximately ASTM type I, here called deionized water),pH and ORP slopes for samples from the same preparationbatch can exhibit a wide range of approximately constantslopes at the ∼20 h monitoring point in the long-termprofile. This may relate to H-bond structural differences,

Table 2. pH Slope Variation with Static Magnetic Field and Stirringa

exposure condition mean slope (pH/h) median slope (pH/h) slope range (pH/h)

stirred with magnets 0.0075 (STD ) 0.003) 0.0081 0.0015-0.012stirred without magnets 0.0065 (STD ) 0.003) 0.0064 0.0019-0.011standing without magnets 0.0037 (STD ) 0.0017) 0.0038 0.001-0.0065

a Slope is larger with stirring than without (p-value < 0.025). The mean slope stirred with magnet is 1.64 times larger than that withstirring only ((0.94, p-value < 0.10). Distilled water; 10 stirred samples in each condition.

Table 3. ORP Slope Is Greater for Ambient (AF) than Zero (ZF) Magnetic Fielda

exposure condition mean slope (mV/h) median slope mV/h) slope range mV/h)

AF 0.16 (STD ) 0.07) 0.16 0.07-0.32ZF 0.076 (STD ) 0.06) 0.049 0.011-0.17ratio 3.75 (STD ) 2.70) 3.58 0.55-7.04

a p-value < 0.005. Unstirred deionized water; 12 samples in each condition.

Figure 6. pH of stirred water, with and without magnets. Afew minutes before t ) 0, sample A was stirred between twomagnets and sample B was stirred without magnets. After lineartrends developed, homogeneity of water, and system reliability,were demonstrated by switching probes between samples.(Distilled water.) Meter: Denver150.

Figure 7. Extremely slow ORP equilibration in zero field,compared with ambient field. In zero field, ORP often stabilizedat levels where it would not, if in an ambient field. (Deionizedwater, aged 4 days.) Meter:Denver250.

Figure 8. (a) Larger pH change when stirred in zero field thanin ambient field. (Deionized water, stored 2 weeks under typicalconditions before stirring, and continued after.) Meter: Denver250. (b) Large ORP change when stirred in zero field; no changein ambient field. (deionized water.) Meter: Denver 150. (c) Newlevel of ORP, after stirring in zero field, does not persist in thisexample. (deionized water.) Meter: Denver250.

pH and ORP Equilibration Rates of Water Langmuir, Vol. 19, No. 17, 2003 6855

as distinct from chemical differences, between samples ofthe same batch. Reviewing the data shows the followingspreads of values: (1) The pH slopes for the static water/no dc magnet experiment samples differed by a factor of∼80. (2) The pH slope for the stirred water/no dc magnetsamples differed by a factor of∼10. (3) For the static water/with dc magnet case, the spread was a factor of ∼5. (4) Forthe stirred water/with dc magnet case, the spread was afactor of ∼8. (5) For the ZF case, the spread was a factorof ∼15.

The measurements in Tables 1-3 were made withdistilled water and deionized water, over a period ofmonths, during which the quality of the water supply couldhave varied. Even with the Millipore system, dependingon the filter condition, there is inevitable variability oftrace elements over time.

The remarkable fact that pH and ORP measured in ZFappear to very slowly evolve in a series of quite long-termmetastable states, in both the upward and downwarddirections, points to the presence of appreciable activationbarriers for process kinetics that are somehow related tomagnetic or EM fields. Perhaps this kind of behavior isrelated to the morphological nature of the water’s hy-drogen-bond structure. If so, the degree of this structure’srigidity versus malleability may be intimately involvedwith a proton magnetic resonance-type phenomenon thatsomehow enhances the flexibility and glissile nature ofthe H-bond network.

Long-time pH and ORP measurements appear to beessential to characterize purified water’s structural state,as distinct from its chemical state. Of course, O2 and CO2equilibration of the samples with ambient air is typicallya fairly slow process but can be speeded up considerablyby stirring. This is well understood. What is not so wellunderstood is the enhancement effect associated with thepresence of either a dc magnetic field or an ac EM field.

Certainly, one expects diamagnetophoresis-type forcesto be acting on the water samples via both dc magneticand ac EM fields. In addition, for ac fields, dielectro-phoresis-type and magnetic resonance-type forces arepresent. Although such forces would enhance the effectivediffusion coefficient for various dipolar moieties in thewater, the unenhanced diffusion coefficients are suf-ficiently large (D ∼ 5 × 10-6 cm2 s-1) to allow diffusionalmixing over distances of ∼0.1 cm in ∼30 min. This is atime much shorter than the phenomena we are dealingwith in these experiments, yet the kinetic enhancementeffect increases as the field strength increases. One mustalso consider changes in ortho/para water15 ratio in thepresence of magnetic fields, as such changes are likely toinfluence both pH and ORP value.

More than half a century ago, it was shown that theconversion rate between the ortho and para forms ofhydrogen in a condensed phase was of second order.16,17

Silvera18 indicated that, for this to occur, simultaneouschanges must happen in (a) rotational angular momentumby ∆J ) 1 and (b) triplet and singlet nuclear spin states.He also points to the observation of O2 impurities in H2as being an extremely effective catalyst of the ortho/paratransition to develop a magnetic field-screening sphere ofpara molecules around each O2 molecule.

Ilisca and Paris19,20 have recently provided a newelectron-nucleus resonant mechanism to facilitate theortho/para conversion process. However, at the H and ∇H values used in this paper, these effects are expected tobe small and unlikely to explain the rather large pH effectsand ORP effect that we find. On the other hand, if we lookat Silvera’s O2 observations in H2, in diamagnetic water,a similar thermodynamic driving force might exist togenerate H+ ions via the dissociation reaction of H2Owhich, in turn, screen the magnetic field of the dissolvedO2 species so as to ultimately increase the O2 and perhapsalso the CO2 reactions for water in equilibrium with airas H increases.

This brings us to the final point that common laboratoryelectrical equipment, in regular use, provides sufficientlystrong fields to stimulate this seemingly anomalousbehavior of purified water. The influence of such devices,used by the scientific community in their day-to-dayexperiments with aqueous solutions and perhaps manyother fluids, needs to be more carefully studied andunderstood.

Acknowledgment. This work was partially supportedby Ditron, LLC, and the Samueli Institute. The authorswish to thank Professor Norm Sleep and Dr. Walter Dibble,Jr., for helpful guidance during the course of this study,Professor Jim Leckie for the use of his water purificationsystem, and Gravity Probe B for the use of a magneticshield.

Supporting Information Available: Brief descriptionof the procedures developed to enhance the measurementaccuracy sufficient for long-term pH and ORP measurements.This material is available free of charge via the Internet athttp://pubs.acs.org.

LA034506H

(15) Tikhonov, V. I.; Volkov, A. A. Science 2002, 296, 2363.

(16) Motizuki, K.; Nagamiya, T. J. Phys. Soc. Jpn. 1956, 11, 93-104.(17) Peters, G.; Schramm, B. Ber. Bunsen-Ges. Phys. Chem. 1998,

102, 1857-1864.(18) Silvera, I. F. Rev. Mod. Phys. 1980, 52, 393-452.(19) Illisca, E.; Paris, S. Phys. Rev. Lett. 1999, 82, 1788-1791.(20) Paris, S.; Illisca, E. J. Phys. Chem. A 1999, 103, 4964-4968.

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