bluuebunny/crossref_metadata_2025 huggingface dataset:
BRITAIN AND NAPOLEON
Authors: SIMMS BRENDAN
Published: July 2002

The French Revolutionary wars, 1787–1802.
By T. C. W. Blanning. London: Longman,
1996. Pp. xvii+286. ISBN 0-340-56911-5. £15.99.

The wars of Napoleon. By Charles J. Esdaile. London: Longman,
1995. Pp. xii+417.
ISBN 0-582-05955-0. £14.99.

The Younger Pitt: the consuming struggle. By John Ehrman. London:
Constable, 1996.
Pp. xv+911. ISBN 0-09-475540-x. £35.

British victory in Egypt, 1801: the end of Napoleon's conquest.

By Piers Mackesy. London and
New York: Routledge, 1995. Pp. xii+282. ISBN 0-415-04064-7. £45.

Britain and the defeat of Napoleon, 1807–1815.
By Rory Muir. New Haven and London:
Yale University Press, 1996. Pp. xiv+466. ISBN 0-300-06443-8. £29.95.

Traditional historians of war and foreign policy in Britain have often
been accused –
sometimes justly – of all manner of sins, among them Anglo- and Eurocentricity.
There
is no trace, however, of insularity in the five new publications by John
Ehrman, Rory
Muir, Piers Mackesy, Charles Esdaile, and T. C. W. Blanning on the struggle
with
Napoleon. The global sweep of that conflict, to quote
Rory Muir's Britain and the defeat
of Napoleon, forces the historian to address an ‘interlocking

mosaic of problems’ (p. xii),
spanning the Baltic to the Cape of Good Hope, and the Indian subcontinent
to the
Caribbean.
URI BEN-ELIEZER, The Making of Israeli Militarism (Bloomington and Indianapolis: Indiana University Press, 1998). Pp. 290. $35 cloth.
Authors: Sharoni Simona
Published: July 2002

Israel's May 1999 elections featured three newly retired generals, including Ehud Barak, a former chief of staff who was elected prime minister. There was consensus among most political analysts that Barak was elected primarily because of his military background. Moreover, a wellorchestrated public-relations campaign presented Barak as the most likely candidate to revive the peace process that his military commander, Yitzhak Rabin, had started. Few questioned, however, that military credentials have become almost a prerequisite to holding political office in Israel or that someone who devoted most of his life to war-making is indeed the best person to lead a peacemaking process. It would be quite difficult to understand the centrality of the military in Israeli politics, as in almost any other sphere of life, without paying close attention to the processes and practices that have shaped Israeli militarism over time. By providing readers with both the historical context and the socio-political background, Uri Ben-Eliezer's The Making of Israeli Militarism enables us to come to terms with how the “military way,” as he refers to it, came to dominate Israeli politics in general and its relationships with its neighbors in particular.
NAWAL EL SAADAWI, The Innocence of the Devil, trans. Sherif Hetata (Berkeley: University of California Press, 1998). Pp. 278.
Authors: Lamb Connie
Published: July 2002

Originally published in 1994, The Innocence of the Devil, by the Egyptian feminist Nawal El Saadawi, has been reissued in a paperback edition with a striking cover. Included in this edition is a well-written and well-documented Introduction by Fedwa Malti-Douglas, which provides a review of El Saadawi's life, a summary of the story, and insights into many aspects of the book. Malti-Douglas is a professor of Near Eastern Languages and Cultures at Indiana University, Bloomington, and a commentator on El Saadawi's works and life. El Saadawi, a medical doctor and a writer, has used both her fiction and nonfiction as social commentaries on Egyptian—and more specifically, Muslim—society. She was educated in Cairo and the United States, practiced as a physician in Egypt, was director of health education in the Egyptian Ministry of Health from 1958 to 1972, has served on United Nations commissions, and is a practicing psychiatrist. Over the years, she has written several nonfiction books along with numerous short stories and novels. In this book, she comments on many facets of Egyptian culture, but the main thrust is that religion is the underlying cause of women's oppression. She emphasizes theological patriarchy in terms of monotheism (a single male god), the weakness of Eve as fallen woman, a male Satan (the serpent), and males designated as religious leaders who hold authority over women.
Work and Workloads During Industrialization: The Experience of Forgemen in the British Iron Industry 1750–1850
Authors: Evans Chris
Published: July 2002

This article examines the ways in which working practices and workloads changed in the course of British industrialization by tracing the experience of one group of skilled workers: iron forgemen. A well-established historiographical tradition assumes that workers were subjected to a more burdensome discipline during the Industrial Revolution. However, empirical studies of workplace practice in early industrial Britain are scarce, and those few studies that have been attempted stress the continuity of workers' experience. But this study argues for discontinuity, exploiting a range of data on the output levels achieved by individual forge crews c. 1750–c. 1850 to identify substantial increases in the burdens imposed upon forgemen.
RECENT TRENDS African History From Earliest Times to Independence. By

PHILIP CURTIN, STEVEN FEIERMAN,

LEONARD THOMPSON and JAN VANSINA.

Second edition. London and New York: Longman Group, 1995. Pp. xvi +

546. £25 (ISBN 0-582-050707).
Authors: AJAYI J. F. ADE
Published: July 2002

A revised version of this well-known university textbook

provides an opportunity to review some of the tendencies in African

historiography since the publication of the original version in 1978

which marked ‘the coming of age of African history’ after

25 years of research. This new version is intended to reflect ‘a

new level of maturity’ in African historiography with the

publication of all the 16 volumes of the Cambridge History of

Africa and the Unesco General History of Africa, of

which only a few had appeared by 1978. The text has been

‘reworked, updated and expanded’; the book has been

redesigned and reset, and the maps have been redrawn and new ones

added.
TSWANA CHRISTIANS The Realm of the Word: Language, Gender and Christianity in a

Southern African Kingdom. By PAUL LANDAU.

London: James Currey, 1995. Pp. xxix + 249. £35 (ISBN

0-85255-670-5); £14.95 paperback (ISBN

0-85255-620-9).
Authors: BRADFORD HELEN
Published: July 2002

‘Writing history’, claims Paul Landau in a

revealing comment in his epilogue, ‘is an attempt to pin and

mount lives on the page of a book, like butterflies or rose

petals’ (p. 219). The generalization is sweeping, but the tropes

aptly symbolize the type of history written in this book. This is a

subtle, nuanced account of the intertwining of Christianity and

politics in central Botswana from the 1850s to the 1940s. It is deeply

informed by Foucauldian notions of power. Landau, moreover, is

troubled by the implications of exercising power, through the very act

of ‘pinning’ down lives.
The Egalitarian Moment: Asia and Africa,

1950–80. By D. A. LOW. Cambridge: Cambridge

University Press, 1996. Pp. xiv + 131. £10.95, paperback

(ISBN 0-521-56765-3).
Authors: FREUND BILL
Published: July 2002

These four essays by the distinguished historian Anthony Low,

best-known to Africanists for his writings on Uganda, constitute the

Wiles Lectures given at the Queen's University, Belfast in 1994.

Tightly argued, they revolve around a straightforward point. Despite

the political impulse which brought about attempts to create an

egalitarian society in the Asian and African countryside, the dominant

pattern in the generation after the Second World War was one of the

strengthening of the class of rich peasants or kulaks. With a few

exceptions, Low points to the effacement of landlord regimes and

systems based on inequality from above and through status. Attempts to

break the back of the rich peasants succeeded only in certain

authoritarian states such as China and Viet Nam and even then, the

kulaks reasserted themselves. It is the radical experiments such as

Mengistu's Ethiopia and Nyerere's Tanzania that Low best

likes to juxtapose with displays of power and effective accumulation

from below. The implication must be the evisceration of continued

attempts to create an egalitarian countryside. Low ranges widely in

making this point looking at East Africa, Ethiopia, Egypt, Iran,

India, China and the Pacific and his breathtaking sweep makes this

suggestive book an enjoyable read.
Availability of nitrogen after fertilizer applications to cereals
Authors: KING J. A. , SYLVESTER-BRADLEY R. , ROCHFORD A. D. H.
Published: July 2002

An experiment was conducted over seven sites in eastern England sown to winter cereals, whereby the soil mineral nitrogen (N) and N recovery in the crop were measured frequently during the active growth period. Plots received 100 kg/ha fertilizer N on one of three dates in spring (28 March, 11 April and 25 April) on each site in each of the three years (1994 to 1996), and these were compared with controls with no applied N. At one site, uncropped plots were included, and measurements of gaseous N emission, soil respiration, soil microbial biomass and root tissue N concentration were also made. The fertilizer applications boosted yields by at least 3 t/ha at all sites, but apparent recovery of fertilizer N varied throughout the previously known range of 45–85%. Soil type and timing of application had no effect on N recovery, or on final yields. N was mineralized from soil sources throughout the growth period, but mineralization was outweighed by ‘‘immobilization’’ of large amounts of N (around 30 kg/ha) in the soil, chiefly during May when crop growth was most rapid. This occurred on all sites with a crop, but not where the crop was absent. Measured losses of N2 and N2O were very small (<70 g/ha/dayN) on the site where they were measured, and no other evidence of loss or storage of N was found. The apparent recovery of fertilizer N at each site, was almost exactly explained by the amount immobilized during May. We conclude that the poor recovery of spring-applied N was due, not to losses as previously assumed but to temporary immobilization during the period of most active crop uptake. Immobilization was caused primarily by the presence of the crop.
Contribution of dietary sulphur to the interaction

between selenium and copper in sheep
Authors: VAN RYSSEN J. B. J. , VAN MALSEN P. S. M. , HARTMANN F.
Published: July 2002

The effect of concentration of sulphur (S) in a diet

on the interrelationship between copper (Cu) and

selenium (Se) metabolism was investigated in sheep. The animals

received a sheep finishing diet in

individual feeding pens for a period of 74 days. The minerals

were included in the diets according to

a 3×2×2 factorial experimental design. The final

mixtures contained three concentrations of Se;

0·35, 0·88 and 1·34 mg Se (Se added as

Na2SeO3); two concentrations of Cu;

6·7 and 17·0 mg Cu (Cu

added as CuSO4) and two concentrations of S;

2·15 and 3·97 g S (S added as

Na2SO4)/kg dry matter

(DM). An increase in dietary Cu resulted in a significant

(P<0·01) increase in liver Se concentration;

2·30 v. 3·43 mg Se/kg DM for the

low v. the high Cu treatments. The addition of S

reduced the hepatic Se concentration significantly

(P<0·01). This was most pronounced at the

high Cu intake,

resulting in a significant (P<0·05)

three-way interaction between the three minerals, i.e.

the hepatic Se concentrations were 2·53, 2·08,

4·07 and 2·79 mg/kg DM for the low

Cu–low S, low Cu–high S,

high Cu–low S and high Cu–high S treatments,

respectively. Dietary S reduced (P<0·01) the

concentration of Cu in the liver from 678 mg/kg DM at

the low S to 305 mg/kg DM at the high S

intakes. Dietary Se did not change the concentration of

Cu in the liver significantly. Adding S to the

diet caused a reduction (P<0·01) in

the Se concentration of rumen bacteria, i.e. from

3·48 mg/kg

DM in the low S to 1·96 mg/kg DM in the high S

treatments. Selenium concentrations in rumen

bacteria and the liver were the most sensitive to changes

in Se intake, followed by the heart, muscle,

plasma and whole blood. It was concluded that an increase

in S intakes would decrease the

accumulation of both Cu and Se in the liver of sheep,

resulting in a diminishing degree of interaction

between Cu and Se.
Evaluation of sorghum root branching using fractals
Authors: MASI C. E. A. , MARANVILLE J. W.
Published: July 2002

Root branching and architecture play a significant role in water
and nutrient uptake, but description
of these parameters has not been easy due to the difficulty of observing
roots in their natural
arrangement. Fractal geometry offers a novel method for studying the branching
patterns of roots.
Plants of ten diverse sorghum (Sorghum bicolor (L.) Moench) genotypes
(five of African origin, three
of US origin and two hybrids composed of African×US lines) were grown
in root boxes containing
80% sand and 20% fine-textured Sharpsburg silty clay loam topsoil. The
root fractal dimension (D)
and abundance (log K) were determined at nine regions within the
profile. Roots were washed free
of growth media and photographic slides were taken of each region. Values
of D and log K were
determined by projecting photographs onto grids of progressively increasing
sizes. The number of
intersects was regressed on log grid size. Differences in D were
found among genotypes
(1·44[les ]D[les ]1·89) suggesting that these sorghum
genotypes may be associated with greater root branching
patterns. Greater fractal dimension (branching) and abundance values occurred
in the 0–35 and
35–70 cm depths of the soil profile within the root box, indicating
a greater root distribution in that
part of the profile. Significant differences were also noted in branching
patterns for sorghum
genotypes derived from different sources. In general, the African sorghums
were more branched and
deeper rooted than the US-derived genotypes. Results indicated that fractal
dimension can be used
for the description of sorghum root system morphology and provides a good
measure of branching
patterns which can be distinguished.
The effect of genetic merit and concentrate proportion
in the diet on nutrient utilization by lactating dairy
cows
Authors: FERRIS C. P. , GORDON F. J. , PATTERSON D. C. , PORTER M. G. , YAN T.
Published: July 2002

Sixty Holstein/Friesian dairy cows, 28 of high genetic merit and 32 of medium genetic merit, were
used in a continuous design, 2 (cow genotypes)×4 (concentrate proportion in diet) factorial
experiment. High and medium merit animals had Predicted Transmitting Abilities for milk fat plus
protein yield, calculated using 1995 as the base year (PTA95 fat plus protein), of 43·3 kg and 1·0 kg
respectively. Concentrate proportions in the diet were 0·37, 0·48, 0·59 and 0·70 of total dry matter
(DM), with the remainder of the diet being grass silage. During this milk production trial, 24 of these
animals, 12 from each genetic merit, representing three animals from each concentrate treatment,
were subject to ration digestibility, and nitrogen and energy utilization studies. In addition, the
efficiency of energy utilization during the milk production trial was calculated.

There were no genotype×concentrate level interactions for any of the variables measured (P>0·05).
Neither genetic merit nor concentrate proportion in the diet influenced the digestibility of either
the DM or energy components of the ration (P>0·05). When expressed as a proportion of nitrogen
intake, medium merit cows exhibited a higher urinary nitrogen output and a lower milk nitrogen
output than the high merit cows. Methane energy output, when expressed as a proportion of gross
energy intake, was higher for the medium than high merit cows (P<0·05), while urinary energy
output tended to decrease with increasing proportion of concentrate in the diet (P<0·05). In the
calorimetric studies, neither heat energy production, milk energy output and energy retained, when
expressed as a proportion of metabolizable energy intake, nor the efficiency of lactation (kl), were
affected by either cow genotype or concentrate proportion in the diet (P>0·05). However when kl
was calculated using the production data from the milk production trial the high merit cows were
found to have significantly higher kl values than the medium merit cows (0·64 v. 0·59, P<0·05) while
k l tended to fall with increasing proportion of concentrate in the ration (P<0·05). However in view
of the many assumptions which were used in these latter calculations, a cautious interpretation is
required.
The estimation of faeces output in penned cattle by controlled release of chromium oxide and the subsequent accuracy of predicting forage intake with in vitro digestibility
Authors: WILLIAMSON P. J. , HENNESSY D. W. , GOGEL B. J. , BARLOW R.
Published: July 2002

The study examined the reliability of predicting faeces output of cattle from chromium oxide (Cr2O3)
released from a device (CRD) inserted in the rumen. Sixteen steers were selected from four genotypes
and were offered a diet of low quality pasture hay with a protein meal supplement. The steers were
placed in metabolism crates which allowed for total collection of faeces over two 5-day periods, days
6–9 (period 1), and days 13–16 (period 2), of a 20-day extrusion cycle of the CRD. Three faeces
samples were taken from each steer per rectum; grab samples in the a.m. and p.m. and a daily
subsample, that is, a sample of each daily total collected output. Cr2O3 release rates were derived for
each sampling regime (a.m., p.m. and daily from the Cr2O3 content of faeces). These derived rates
were compared with the release rate specified by the supplier to determine differences and any bias
associated with the sampling regimes. Release rates were also derived from the predicted expiry date
calculated from plunger travel in the CRD. Organic matter digestibility of the diet was determined
from measurements of feed intake and faeces output over the 4 days for each steer and from an in
vitro technique on diet samples. Predicted forage intakes were estimated using the mean faeces output
collected over 4 days in combination with either the in vivo or in vitro digestibility estimates.
Correlations between actual forage intake and predicted forage intake for each method were
calculated and the bias in predicted forage intake between methods was compared.

The daily data revealed significant effects of steer (and/or CRD) and sampling period on the
estimated release rate of Cr2O3 from the CRD. However, whilst there was only a period effect on the
release rate with p.m. sampling there was a linear decline in release rate with the a.m. sampling. The
correlation between predicted and actual forage intake was greatly reduced when in vivo digestibility
was replaced by in vitro digestibility.

The results of this study suggest that the CRD had release rates less than specified and therefore
devices should be calibrated for both the animals and the pastures prior to use. Furthermore, faeces
sampling should be restricted to <13 days post-dosing to minimize bias.
FROM EFFICACY TO EFFECTIVENESS: SELECTING INDICATORS FOR A COMMUNITY-BASED LACTATIONAL AMENORRHOEA METHOD PROMOTION PROGRAMME
Authors: BENDER DEBORAH E. , DUSCH ERIN , McCANN MARGARET F.
Published: July 2002

This paper reviews the results of clinical trials and community studies of lactational amenorrhoea and its role as a contraceptive method (LAM). Indicators which are used in efficacy trials and effectiveness interventions are compared and sets of indicators of effectiveness appropriate to community-based LAM programmes are recommended. A five-tiered ecological framework is used to facilitate selection of indicators which range from individual to policy level outcomes. The indicator framework is intended as a tool for health practitioners in family planning and maternal and child health service delivery settings who are interested in designing programmatic interventions for the promotion of LAM, particularly among less well-educated women of lower socioeconomic communities.
The Theology of Thomas Hobbes's Leviathan
Authors: OVERHOFF JÜRGEN
Published: July 2002

In his greatest piece of political philosophy, the Leviathan of 1651,
Thomas Hobbes dedicated the astonishing mass of eighteen voluminous
chapters solely to the discussion of religious matters.
Although his earlier political treatises, The elements of law of 1640 and the
De cive of 1642, discussed theological doctrines at some length, they
never accorded so great a role to questions of religion and theology as did
Leviathan. The two books of Leviathan in which Hobbes promulgated his
theological doctrines are almost exactly equal in length to books I and II,
and one of the chapters in book III (‘Of power ecclesiasticall’) is in some
ways the longest chapter in the work. The kind of contentious
eschatological doctrines which Hobbes had been careful to leave
unchallenged in his early works, namely the question whether the soul
had an independent existence after the death of the body, figured
particularly high in Leviathan. Why was it that Hobbes's interest in
theology increased so sharply between 1642 and 1651, and what was the
particular point of the theology of Leviathan?
Apologia pro Vitis Veteriorum Hominum
Authors: HILTON BOYD
Published: July 2002

The Oxford Movement in context. Anglican High Churchmanship,

1700–1857. By Peter
Benedict Nockles. Pp. xvii+342. Cambridge: Cambridge University Press,

1994. £40 (cloth), £15.95 (paper). 0 521 38162 2; 0 521 58719
0

This book, together with subsequent articles on Scotland and
Ireland, contains the fruits of researches which first became
available in Dr Nockles's Oxford DPhil. of 1982, probably the
most widely consulted dissertation on religious developments in
eighteenth- and nineteenth-century Britain since John Walsh's
Cambridge PhD of 1956. The outlines of the argument have been
adumbrated elsewhere, but God (in Nockles's case) resides also in
the
details, and historians will turn to this book for its rich scholarship
and its
staggering mastery of published and unpublished sources. Indeed the
appearance of this definitive study is doubly welcome because, so long
as
it was known to be in the offing, there was a danger that other historians

would be deterred from starting research on the subject of Anglican High

Churchmanship, but now that it is out it will inevitably act as a guide
and
stimulus to further inquiry. Already scholars such as Stewart Brown,
Arthur Burns, Frances Knight, Simon Skinner and Brian Young are
beginning to till the ground. A field which had once seemed high and dry

has been refreshed and made fertile.
Laboratory simulation of the rise of buoyant thermals created by open detonation
Authors: THOMPSON ROGER S. , SNYDER WILLIAM H. , WEIL JEFFREY C.
Published: July 2002

Laboratory experiments were conducted in a water tank to investigate the rise through
the atmosphere of thermals generated by the detonation of surplus military munitions.
The fall of a dense volume of fluid through the water in the tank follows the same
governing equations as the rise of a buoyant volume of gas in the atmosphere. By
filling the tank with a layer of water and a layer of salt water, an elevated step
change in density was obtained, simulating a temperature inversion or jump in the
atmosphere. The growth of the linear dimensions of the thermal and its volume were
determined and used in the development of a criterion for predicting when a thermal
will fully penetrate the inversion. Replacing the second layer of fluid with water of
gradually increasing salinity, an elevated constant density gradient was obtained. In
these cases, the maximum penetration distance of the thermal was observed and the
equilibrium position and vertical spread were determined experimentally.

These observations and the empirical relationships determined from them should
prove useful in the development and evaluation of air pollution dispersion models for
predicting the atmospheric transport and diffusion of material released during such
detonations.
On the structure of a Taylor column driven by a buoyant parcel in an unbounded rotating fluid
Authors: LOPER DAVID E.
Published: July 2002

The velocity and pressure fields produced in a homogeneous rapidly rotating fluid
driven by an isolated buoyant parcel are investigated. Gravity and rotation are
allowed to have arbitrary orientations and the parcel shape is assumed Gaussian.
Inertial forces and time-dependent effects are ignored. The linear problem is easily
solved by three-dimensional Fourier transform, and the inversion is facilitated by
assuming the Ekman number, E, to be very small. In this limit the fields form a
Taylor column extended in the direction of the rotation axis. In the absence of rigid
boundaries no boundary layers occur. The velocity and pressure in the vicinity of the
parcel are found in closed form while elsewhere (within the Taylor column) they are
expressed in terms of relatively simple scalar integrals which are easily evaluated.

Within the buoyant parcel, the momentum balance is baroclinic, involving Coriolis,
pressure and buoyancy forces. Outside the parcel, the balance is geostrophic at unit
order. The viscous force is important at order E and determines the axial structure of
the Taylor column. In contrast to the case of flow driven by a rigid body, no ‘Taylor
slug’ of recirculating flow occurs. The velocity and pressure decay algebraically with
distance from the parcel, with the scale of variation being a/E in the axial direction
and a in the radial direction, where a is the parcel radius. In the vicinity of the parcel,
the return flow occurs in a broad region surrounding the parcel. The structure of flow
in the vicinity of the parcel is independent of the Ekman number. This return flow
sweeps the fringes of the parcel backward, making the net rise speed significantly
slower than that of a rigid sphere of identical buoyancy. The return flow also acts to
deform the parcel; this deformation is quantified.
The effect of convective heat transfer on unsteady boundary-layer separation
Authors: CASSEL K. W.
Published: July 2002

The unsteady evolution of a boundary layer induced by a rectilinear vortex convecting
above a heated surface is considered numerically. This model problem is
representative of the types of interactions that can occur when vortices encounter
solid surfaces in a wide variety of diverse applications involving high-Reynolds-number
and high-Grashof-number flows. It is known that in the case without heat
transfer, the vortex-induced boundary layer evolves toward a singularity as it forms a
sharp spike that erupts away from the surface. Numerical solutions of the unsteady
mixed-convection boundary-layer equations in the Boussinesq limit are obtained in
Lagrangian coordinates. Solutions for various values of the inclination angle of the
surface and Grashof number show that the coupling between the fluid flow and heat
transfer can have a dramatic effect upon the transport of momentum and energy
within the boundary layer induced by the vortex. The unsteady eruption convects
high-temperature, near-wall fluid away from the surface and causes large gradients in
the thermal boundary layer. The buoyancy force acting on the heated boundary-layer
fluid can also have a significant impact on the unsteady separation process, either
accelerating or delaying it, depending upon the inclination angle of the surface.
Receptivity of boundary layers with distributed roughness to vortical and acoustic disturbances: a second-order asymptotic theory and comparison with experiments
Authors: WU XUESONG
Published: July 2002

This paper investigates the receptivity of boundary layers due to distributed roughness
interacting with free-stream disturbances. Both acoustic and vortical perturbations
are considered. An asymptotic approach based on the triple-deck formulation has
been developed to determine the initial amplitude of the Tollmien–Schlichting wave to
the O(R−1/8) accuracy, where R is the global
Reynolds number. In the case of vortical
disturbances, we show that the dominant contribution to the receptivity comes from
the upper deck as well as from the so-called edge layer centred at the outer reach of
the boundary layer. It is found that for certain forms of disturbances, the receptivity
is independent of their vertical structure and can be fully characterized by their slip
velocity at the edge of the boundary layer. A typical case is the vortical disturbance
in the form of a convecting wake, for which the same conclusion as above has been
reached by Dietz (1999) on the basis of measurements. Our theoretical predictions
are compared with the experimental data of Dietz (1999), and a good quantitative
agreement has been found. Such a comparison is the first to be made for distributed
vortical receptivity. Further calculations indicate that the vortical receptivity in general
is much stronger than was suggested previously. In the case of acoustic disturbances,
it is found that our first-order theory is in good agreement with experiments as well
as with previous theoretical results. But the second-order theory over-predicts, and
the possible reasons for this are discussed.
Chaotic advection in bounded Navier–Stokes flows
Authors: MEZIĆ IGOR
Published: July 2002

We discuss mixing and transport in three-dimensional, steady, Navier–Stokes flows
with the no-slip condition at the boundaries. The advective flux is related to the
dynamics of the Navier–Stokes equations and a prediction is made of the scaling
of the advective flux with the Reynolds number: the flux is expected to decay as
the Reynolds number goes to infinity. This prediction is made via a Melnikov-type
calculation together with boundary layer concepts through which the flow is split
into an integrable and a small non-integrable part. The rate of decay is related to the
details of viscous flow in boundary layers. The Melnikov function is related to the
Bernoulli integral of the underlying Euler flow. The effects of molecular diffusivity
are discussed and the effective axial diffusivity scaling predicted as a function of
Reynolds and Péclet numbers. Using these ideas, we study the mass transport in
the wavy vortex flow in the Taylor–Couette apparatus as a particular example.
We propose an explanation of the observed non-monotonic behaviour of flux with
increasing Reynolds number that was not captured in any of the previous models. It
is shown that there is a Reynolds number at which the axial flux in the wavy vortex
flow is maximized. At the low range of Reynolds numbers for which the wavy vortex
flow is stable the flux increases, while for large Reynolds numbers it decreases. We
compare these predictions with the available experimental and numerical data on the
wavy vortex flow.
Instabilities induced by concentration gradients in dusty gases
Authors: HERNÁNDEZ JUAN A.
Published: July 2002

This paper deals with the stability of suspensions modelled as dusty gases for non-uniform
profiles of mass fraction of particles. It is known that a stationary uniform
fluidized bed may be unstable to small disturbances which grow until a secondary
instability develops forming bubbles that rise through the bed. Interactions between
particles are difficult to model and this makes it necessary to close the model with
some assumptions. However, in dilute fluidized beds which are characterized by a
low volume fraction of particles, interactions between particles are negligible and
this motivates the study of instabilities of suspensions by means of the dusty gas
equations, avoiding the problem of particular closures.

We show in this work that suspensions blown to regions of higher concentration are
unstable to two-dimensional disturbances. An equation which governs this instability
is obtained. A physical mechanism is proposed to explain this instability and it is
related to the Rayleigh–Taylor one in the limit of long characteristic lengthscales
associated with the concentration profile. Finally, the evolution of this instability is
followed using a fully nonlinear numerical code showing the formation of streamers
and clusters of particles.
Longitudinal and transverse structure functions in a turbulent round jet: effect of initial conditions and Reynolds number
Authors: ROMANO G. P. , ANTONIA R. A.
Published: July 2002

The difference between scaling exponents of longitudinal and transverse velocity
structure functions in the far-field of a round jet is found to depend on the anisotropy
of the flow. The effect of the large-scale anisotropy is assessed by considering different
initial conditions at the jet nozzle, and hence different ratios of the longitudinal to
transverse rms velocities. The effect of the Taylor microscale Reynolds number on
the small scale anisotropy is also considered. Both effects account, to a large extent,
for the observed difference between longitudinal and transverse exponents and the
disagreement between previously published results of different authors. This disagreement
also depends on the method used to determine the inertial range. An empirical
description of the overall behaviour of the structure functions provides reasonable
estimates for the longitudinal and transverse exponents, accounting reasonably well
for the anisotropy of both large- and small-scale motions.
Eulerian and Lagrangian velocity correlations in

two-dimensional random geostrophic flows
Authors: PÉCSELI H. L. , TRULSEN J.
Published: July 2002

Random flows in rotating fluid layers are studied in two spatial

dimensions. The

Eulerian and Lagrangian correlation functions for such flows are analysed
by

approximating the actual two-dimensional flow by an autonomous system consisting
of

many overlapping and mutually convecting vortices. Analytical expressions
for the

full space–time-varying Eulerian velocity correlation are derived
solely

in terms of

flow parameters. An extension of the arguments giving these results also
allows the

derivation of analytical expressions for the Lagrangian velocity

correlation function.

The analytical results are supported by a numerical simulation.
Stability of the flow of a fluid through a flexible
tube at intermediate Reynolds number
Authors: KUMARAN V.
Published: July 2002

The stability of the flow of a fluid in a flexible tube is analysed
over a range
of Reynolds numbers 1<Re<104 using a linear
stability analysis. The system
consists of a Hagen–Poiseuille flow of a Newtonian fluid of density
ρ, viscosity
η and maximum velocity V through a tube of radius R

which is surrounded by
an incompressible viscoelastic solid of density ρ, shear modulus G
and viscosity
ηs in the region R<r<HR.
In the
intermediate Reynolds number regime, the
stability depends on the Reynolds number Re=ρVR/η,

a dimensionless parameter [sum ]=ρGR2/η2,

the ratio of viscosities ηr= ηs/η,

the ratio of radii H and the
wavenumber of the perturbations k. The neutral stability curves
are obtained by
numerical continuation using the analytical solutions obtained in the zero
Reynolds
number limit as the starting guess. For ηr=0,
the flow becomes unstable when
the Reynolds number exceeds a critical value Rec,

and the critical Reynolds number
increases with an increase in [sum ]. In the limit of high Reynolds number,
it is found
that Rec∝[sum ]α, where

α varies between 0.7 and 0.75 for H between 1.1 and 10.0.

An analysis of the flow structure indicates that the viscous stresses are
confined to a
boundary layer of thickness Re−1/3 for Re[Gt ]1,

and the shear stress, scaled by ηV/R, increases
as
Re1/3. However, no simple
scaling law is observed for the normal stress even at
103<Re<105, and consequently the critical
Reynolds
number also does not follow a simple scaling relation. The effect of
variation of ηr on the stability is
analysed, and it is found that a variation in ηr

could qualitatively alter the stability
characteristics. At relatively low values of [sum ] (about 102),

the system could become unstable at all values of ηr,

but at relatively high values of [sum ] (greater than about 104),

an instability is observed only when the viscosity ratio is below a maximum

value η*rm.
The coupling of waves and convection
Authors: STAMP ANDREW P. , HUGHES GRAHAM O. , NOKES ROGER I. , GRIFFITHS ROSS W.
Published: July 2002

Experiments with layers of salt and sugar solution separated by
a diffusive interface
are described. Interfacial waves were spontaneously generated by the convection

once the system evolved to a critical value of the density-anomaly ratio

Rρ≡βΔS/αΔT.

The waves locally modulated the interfacial fluxes by modifying the
interface thickness and thereby organized otherwise random convective motions
into
large-scale circulations. In turn, the waves themselves persisted for unusually
long
times owing to energy input from the organized convection. The dependence
of the
wave speed on the layer properties and channel dimensions was successfully
predicted
by assuming that coupling requires a matching of the wave and convection
speeds, and
that the system selects waves of an amplitude for which this resonance
can occur. This
‘wave–convection coupling’ also appeared to
increase the interfacial fluxes at low Rρ.
The interaction of waves and convection may be important for oceanic thermohaline

staircases and other systems where convection is driven by interfacial
fluxes.
The stress singularity in surfactant-driven
thin-film flows. Part 2. Inertial effects
Authors: JENSEN O. E.
Published: July 2002

A localized, insoluble, surfactant monolayer, spreading
under the action of surface-tension
gradients over a thin liquid film, has at its leading edge an integrable
stress
singularity which renders conventional thin-film approximations locally
non-uniform.
Here high-Reynolds-number asymptotics are used to explore the quasi-steady
two-dimensional
developing flow near the monolayer tip, assuming that gravity keeps the

free surface almost flat, that weak ‘contaminant’
surfactant regularizes the singularity
and that the monolayer spreads fast enough for inertial effects to be important
in
a region which is long compared to the film depth but which is short compared

to the length of the monolayer. It is shown how downward displacement of
the
inviscid core flow by the subsurface viscous boundary layer yields a non-uniform

pressure distribution which, when the monolayer is spreading fast enough
for cross-stream
pressure gradients to be significant at its tip, creates a short free-surface
hump
which is the thin-film version of a Reynolds ridge. The ridge and other
singular
flow structures are smoothed as the monolayer slows and levels of contaminant

are increased. The conditions under which lubrication theory provides a
uniformly
accurate approximation for this class of surfactant-spreading flows are
established.
Energy constraints in forced recirculating MHD flows
Authors: KINNEAR D. , DAVIDSON P. A.
Published: July 2002

We are concerned here with forced steady recirculating flows which
are laminar,
two-dimensional and have a high Reynolds number. The body force is considered

to be prescribed and independent of the flow, a situation which arises
frequently in
magnetohydrodynamics. Such flows are subject to a strong constraint. Specifically,

the body force generates kinetic energy throughout the flow field, yet
dissipation is
confined to narrow singular regions such as boundary layers. If the flow
is to achieve
a steady state, then the kinetic energy which is continually generated
within the bulk
of the flow must find its way to the dissipative regions.
Now the distribution of u2/2 is
governed by a transport equation, in which the only cross-stream transport
of energy
is diffusion, v∇2 (u2/2).

It follows that there are only two possible candidates for the
transport of energy to the dissipative regions: the energy could be diffused
to the
shear layers, or else it could be convected to the shear layers through
entrainment
of the streamlines. We investigate both options and show that neither is
a likely
candidate at high Reynolds number. We then describe numerical experiments
for a
model problem designed to resolve these issues. We show that, at least
for our model
problem, no stable steady solution exists at high Reynolds number. Rather,
as soon
as the Reynolds number exceeds a modest value of around 10, the flow becomes

unstable via a supercritical Hopf bifurcation.
Experimental study of vortex breakdown in swirling jets
Authors: BILLANT PAUL , CHOMAZ JEAN-MARC , HUERRE PATRICK
Published: July 2002

The goal of this study is to characterize the various breakdown
states taking place
in a swirling water jet as the swirl ratio S and
Reynolds number Re are varied. A
pressure-driven water jet discharges into a large tank, swirl being imparted
by means
of a motor which sets into rotation a honeycomb within a settling chamber.
The
experiments are conducted for two distinct jet diameters by varying the
swirl ratio
S while maintaining the Reynolds number
Re fixed in the range 300<Re<1200.
Breakdown is observed to occur when S reaches a well defined threshold

Sc≈1.3–1.4
which is independent of Re and nozzle diameter used. This critical
value is found to
be in good agreement with a simple criterion derived in the same spirit
as the first
stage of Escudier & Keller's (1983) theory. Four distinct forms
of vortex breakdown
are identified: the well documented bubble state, a new cone configuration
in which
the vortex takes the form of an open conical sheet, and two associated
asymmetric
bubble and asymmetric cone states, which are only observed at large Reynolds

numbers. The two latter configurations differ from the former by the precession
of
the stagnation point around the jet axis in a co-rotating direction with
respect to the
upstream vortex flow. The two flow configurations, bubble or cone, are
observed to
coexist above the threshold Sc at the same
values of the Reynolds number Re and
swirl parameter S. The selection of breakdown state is extremely
sensitive to small
temperature inhomogeneities present in the apparatus.
When S reaches Sc, breakdown
gradually sets in, a stagnation point appearing in the downstream turbulent
region
of the flow and slowly moving upstream until it reaches an equilibrium
location.
In an intermediate range of Reynolds numbers, the breakdown threshold displays

hysteresis lying in the ability of the breakdown state to remain
stable for S<Sc
once it has taken place. Below the onset of breakdown, i.e.
when 0<S<Sc, the
swirling jet is highly asymmetric and takes the shape of a steady helix.
By contrast
above breakdown onset, cross-section visualizations indicate that the cone
and the
bubble are axisymmetric. The cone is observed to undergo slow oscillations
induced
by secondary recirculating motions that are independent of confinement
effects.
Two-phase modelling of a fluid mixing layer
Authors: GLIMM J. , SALTZ D. , SHARP D. H.
Published: July 2002

We analyse and improve a recently-proposed two-phase flow model
for the statistical
evolution of two-fluid mixing. A hyperbolic equation for the volume fraction,
whose
characteristic speed is the average interface velocity v*,
plays a central role. We
propose a new model for v* in terms of the volume fraction
and fluid velocities, which
can be interpreted as a constitutive law for two-fluid mixing. In the incompressible

limit, the two-phase equations admit a self-similar solution for an arbitrary
scaling of
lengths. We show that the constitutive law for v* can be expressed
directly in terms
of the volume fraction, and thus it is an experimentally measurable quantity.
For
incompressible Rayleigh–Taylor mixing, we examine the self-similar
solution based
on a simple zero-parameter model for v*. It is shown that
the present approach gives
improved agreement with experimental data for the growth rate of a Rayleigh–Taylor

mixing layer.

Closure of the two-phase flow model requires boundary conditions for
the surfaces
that separate the two-phase and single-phase regions, i.e. the edges of
the mixing layer.
We propose boundary conditions for Rayleigh–Taylor mixing based on
the inertial,
drag, and buoyant forces on the furthest penetrating structures which define
these
edges. Our analysis indicates that the compatibility of the boundary conditions
with
the two-phase flow model is an important consideration. The closure assumptions

introduced here and their consequences in relation to experimental data
are compared
to the work of others.
Turbulent fountains in a confined stratified environment
Authors: BLOOMFIELD LYNN J. , KERR ROSS C.
Published: July 2002

An experimental and theoretical investigation of the flow and density distribution
arising from the upward turbulent injection of a dense fluid into a stratified environment
of finite extent is presented. Initially, the rising fluid reaches a maximum height
before the flow reverses direction and intrudes either along the base of the tank or
at an intermediate height in the environment. As more dense fluid is added through
either a point or line source, both the fountain and the environment evolve with time.
We determine expressions for the motion of the ascending and descending ‘fronts’
that mark the vertical extent of the spreading layer. We also consider the changes to
the environmental density profile and determine an expression for the rate at which
the top of the fountain rises due to these changes. Finally, we apply our results
quantitatively to two physical problems: the replenishment of magma chambers and
the heating or cooling of a room.
Impulse formulation of the Euler equations:
general properties and numerical methods
Authors: RUSSO GIOVANNI , SMEREKA PETER
Published: July 2002

The gauge freedom of the incompressible Euler equations is explored. We present
various forms of the Euler equations written in terms of the impulse density. It is
shown that these various forms are related by a gauge transformation. We devise a
numerical method to solve the impulse form of the Euler equations in a variety of
gauges. The numerical scheme is implemented both in two and three space dimensions.
Numerical results are presented showing that the impulse density tends to concentrate
on sheets.
Generation of Tollmien–Schlichting waves by
convecting gusts interacting with sound
Authors: WU XUESONG
Published: July 2002

A new mechanism is proposed for the generation of Tollmien–Schlichting (T–S)
waves by free-stream turbulence. For definiteness and self-consistency, the mechanism is
described mathematically by using a triple-deck formalism. The free-stream turbulence
is represented by convecting gusts consisting of the so-called vortical and entropy
waves of small amplitude. We show that suitable convecting gusts can interact with
sound waves in the free stream to produce a forcing that has the same time and
length scales as those of the T–S waves, thereby exciting such waves in the vicinity
of the lower branch of the neutral stability curve. The T–S waves so produced
have the order of magnitude of ε2R5/16,
where ε is the amplitude of the free-stream
disturbance and R the global Reynolds number. The scale conversion is achieved
without resorting to any non-homogeneity on the wall, and hence the mechanism
operates in a flat boundary layer. Furthermore, the T–S waves so generated do not
undergo any immediate decay, as they may do in some other receptivity processes.
For homogeneous isotropic free-stream turbulence, the spectrum of the T–S waves
is obtained. The efficiency of the receptivity mechanism is assessed by parametric
studies.