bluuebunny/crossref_metadata_2025 huggingface dataset:
CIVIL THEOLOGY AND CHURCH ESTABLISHMENTS IN REVOLUTIONARY AMERICA
Authors: KIDD COLIN
Published: July 2002

The discourse of America's founding generation, it is now widely recognized, was rich
and variegated in its composition, drawing upon the commonwealth tradition, the English common
law, Montesquieu, Locke, Scottish moral philosophy, and the classics. These sources yield significant
clues as to how eighteenth-century Americans viewed religious liberty and church–state relations,
subjects of the First Amendment to the Constitution. Supplementing the work of legal historians on the
religious provisions of the early state constitutions, the study of political ideas suggests the parameters
of the eighteenth-century debate over the effects which various types of religious belief and ecclesiastical
establishment had upon manners and institutions. It also reveals the ideological underpinnings of the
apparently inconsistent legal provisions for religion at the state level, and, far from settling the elusive
question of ‘original intent’, highlights the nature of the divisions within the founding generation.
YEZID SAYIGH, Armed Struggle and the Search for State: The Palestinian National Movement, 1949–1993 (Washington, D.C.: Institute for Palestine Studies, and Oxford: Clarendon Press, 1997). Pp. 96. £70.00 cloth.
Authors: Lesch Ann M.
Published: July 2002

Yezid Sayigh's encylopedic history focuses on the role that the idea of armed struggle played in the Palestinian national movement as it evolved over the past half-century. His central thesis is that “armed struggle provided the political impulse and organisational dynamic in the evolution of Palestinian national identity and in the formation of parastatal institutions and a bureaucratic elite, the nucleus of government” (p. vii). The concept of armed struggle reforged Palestinian national identity, mobilized Palestinians, provided political legitimization to the Palestinian movement, made the Palestinians a distinct political actor in relation to the Arab states, helped to create institutions that could form the basis of a government, and established a well-defined political elite. Thus, even though Palestinian leaders never transformed the armed struggle into a people's war along the lines of Algeria or Vietnam, and never liberated any part of Palestine by force, armed struggle served other important, statist functions.
ISLAMIC MORALITY IN LATE OTTOMAN “SECULAR” SCHOOLS
Authors: Fortna Benjamin C.
Published: July 2002

Recent scholarship has taken great strides toward integrating the history of the late Ottoman Empire into world history. By moving beyond the view that the West was the prime agent for change in the East, historians have shed new light on indigenous efforts aimed at repositioning the state, reconceptualizing knowledge, and restructuring “society.”1 A comparative perspective has helped students of the period recognize that the late Ottoman Empire shared and took action against many of the same problems confronting its contemporaries, East and West. The assertion of Ottoman agency has been critical to finishing off the stereotype of the “sick man of Europe,” but the persistent legacies of modernization theory and nationalist historiography continue to obscure our view of the period.
The Latin American Labor Studies Boom
Authors: French John D.
Published: July 2002

The contemporary North Atlantic world has been marked by a waning enthusiasm for and salience of the study of workers. Yet the current ebb “in the traditional capitalist ‘core’ countries” (not to mention eastern Europe), Marcel van der Linden recently suggested, is far from being a “crisis” in the field of labor history as such. Rather, it is best understood as “only a regional phenomenon” since in much of “the so-called Third World, especially in the countries of the industrializing semi-periphery, interest in the history of labor and proletarian protest is growing steadily”. Citing encouraging recent developments in labor history in Asia, he noted how the field has grown in parallel with “the stormy conquest of economic sectors by the world market [which] has led to a rapid expansion of the number of waged workers, and the emergence of new radical trade unions”. Van der Linden's description fits well the study of labor in Latin America and the Caribbean, where the field first gained visibility in the early to mid-1980s and has now won recognition as an established specialization among scholars of many disciplines. After surveying the Latin American boom and its political context, this article offers a Brazilian/North Atlantic example in order to illustrate the intellectual gains, for students of both areas, that come with the transcendence of geographical parochialism.
Unions and Information, Britain 1900–1960: An Essay in the History of Information
Authors: Mutch Alistair
Published: July 2002

This article examines the use of information by British trade unions to react to occupational change. Using a case study of the response to welding by the Boilermakers' Society, it looks at the barriers that prevented the use of information. It then examines the rise of trade union research departments. This leads to an outline of a framework for looking at the ways in which trade unions used information, based on their attitude towards their environment. The article suggests that an “information perspective” is a useful supplement to existing ways of examining trade union history which may shed new light on their development.
CHRISTIANITY IN AFRICA Christianity in Africa: The Renewal of a Non-Western

Religion. By KWAME BEDIAKO. Edinburgh:

Edinburgh University Press and Maryknoll, NY: Orbis, 1995. Pp. xii +

276. £16.95 (ISBN 0-7486-0625-4).
Authors: WARD KEVIN
Published: July 2002

Kwame Bediako is one of a new generation of West African

Christian scholars, who confidently assert the essential

‘Africanness’ of African Christianity against all inclined

to emphasize its foreignness. While deeply indebted to the first

generation of African theologians of the 1960s, Bediako feels that

they accepted too readily that Christianity was a foreign religion

which needed to be ‘Africanized’ by incorporating elements

from the traditional African religious heritage. It was the posing of

this stark dichotomy – Christian or African? – which in

Bediako's view led the Ghanaian Catholic priest Osofo Damuah to

renounce Christianity and to found his own neo-traditional African,

explicitly non-Christian, religious movement,

‘Afrikania’.
PORTUGUESE CENTURY IN GUINEA São Jorge da Mina 1482–1637. La vie

d'un comptoir portugais en Afrique occidentale. Par J.

BATO'ORA BALLONG-WEN-MEWUDA.

Lisbon and Paris: École des Hautes Études en Sciences

Sociales, collection du Centre d'Études Portugaises:

Fondation Calouste Gulbenkian/Commission Nationale pour les

Commémorations des Décourvertes Portugaises, 1993. 2

vols. Pp. 642. No price given (ISBN 972-95871-3-2).
Authors: HAIR P. E. H.
Published: July 2002

The foundations of Afro-European relations were laid in the

first one hundred or so years of contact, the period from the 1440s to

at least the 1550s during which Portuguese activities in Guinea

proceeded without grossly damaging interference from other European

powers. From 1482 up to the final disaster of capture by the Dutch in

1637, the fort of Sáo Jorge da Mina was the principal base for

official Portuguese activities, ‘Mina’ being the conduit

for the most extensive sea-export of gold. Despite its economic value

to the crown, and its international status as the symbol of the

Portuguese claim to sovereignty over Guinea and monopoly of the

sea-export trade of western Africa, the fort had probably less lasting

influence on early Afro-European relations than had the less heralded,

and even more poorly recorded, activities of private Portuguese

traders in western Guinea. Nevertheless, the history of the fort, when

Portuguese, deserves close attention, and these two volumes by Joseph

Bato'ora Ballong-wen-Mewuda represent a brave attempt to provide

an analytical account.
The Frontier States of Western Yorubaland,

1600–1889. By BIODUN ADEDIRAN.

Ibadan: Institut Français de Recherche en Afrique, 1994. Pp.

x + 248. No price given (ISBN 978-2015-25-3).
Authors: LOVEJOY PAUL E.
Published: July 2002

The identification of the various sub-groups of the Yoruba

offers a challenge to historians, particularly since large numbers of

Yoruba-speaking people were deported into the African diaspora. In

this contribution to Yoruba historiography, Adediran analyses the

history of the western Yoruba sub-groups, especially those resident in

République du Benin and also in Togo. This study expands upon

Adediran's Ph.D. thesis (Awolowo University, 1980) and is based

on oral traditions and archival materials, as well as an excellent

grasp of the published literature.
POLITICS AND VIOLENCE IN THE ‘RUSSIAN ZONE’: CONFLICT IN NEWCLARE SOUTH, 1950–7
Authors: KYNOCH GARY
Published: July 2002

The urban townships of South Africa have been contested terrain since their
inception. Different groups have struggled to control territory, various
resources and political activities within the confines of the locations and, all
too frequently, violence has been an integral part of these struggles. Groups
as varied in composition and ideology as squatter movements, well-organized
criminal outfits, student groups, vigilantes, traditional courts (makgotlas),
migrant gangs, youth gangs, municipal political groups and national political
movements – with much overlapping between these categories – have all at
one time or another sought to impose their will on township residents and
have regarded violence as an essential element in their campaigns.

While much attention has been deservedly devoted to the violence
employed by the state as a means of subjugating, dividing and controlling
township residents, the different ways in which black urban groups struggled
to assert control over their environments have received relatively little
scrutiny. These processes cannot be regarded in isolation from the state's
quest for control, but neither should they be subsumed by the larger focus
on a revolutionary struggle. Rather, I would argue that a more informed
understanding of the conditions and challenges faced by black urbanites
requires study of the nature of localized power and violence within the
townships. African groups pursued agendas which served their own interests
and had a considerable impact on social relations and perceptions of power
and authority, both within the locations and in the broader context of
national/racial politics.
Effects of applications of N fertilizers and nitrification inhibitors on dry matter and essential oil yields of Java citronella (Cymbopogon winterianus Jowitt.)
Authors: PUTTANNA K. , NANJE GOWDA N. M. , PRAKASA RAO E. V. S.
Published: July 2002

A field experiment was conducted for 2 years (1993–95) at Central Institute of Medicinal and Aromatic Plants, Field Station, Bangalore, India to evaluate the nitrification inhibitors, benzotriazole, o-nitrophenol, m-nitroaniline and dicyandiamide in a perennial aromatic grass, Java citronella. Citronella responded to applications of high doses of nitrogen (300 kg N/ha/year). The interaction between N doses and nitrification inhibitors was significant. Nitrification inhibitors performed better at the highest N dose (450 kg N/ha/year) and the increase in the essential oil yields was to an extent of 27·3 to 34·6% when compared with ‘N alone’ treatment. The nitrification inhibitors also increased the apparent N recoveries by citronella considerably. The oil content in the herb and its quality were not affected by the treatments. The nitrification inhibitors increased citronella yields and improved N economy.
The introduction of animal traction into inland valley

regions. 2. Dry season cultivation and the use of herbicides in rice
Authors: LAWRENCE P. R. , DIJKMAN J. T.
Published: July 2002

Rice was grown in an inland valley (fadama) region of central Nigeria.

Plots were cultivated using

oxen either in the dry season or at the beginning of the wet season. Around

25% more time was

required for dry season cultivation but this enabled an average saving
of

53·5 h/ha during the most

critical time of the year at the beginning of the wet season. Total time
for

all operations during the

year was similar (2075 and 2150 h/ha for dry and wet season respectively)

of which most was spent

on weeding (1388 and 1527 h/ha). Weeding time could be reduced by

the application of pre-emergence herbicide to 1042 and 1247 h/ha for

dry and wet season cultivation respectively. Grain

yields were 4·0, 4·8, 4·2 and 4·6 t dry

matter/ha for dry season/no herbicide, dry season/herbicide,

wet season/no herbicide, and wet season/herbicide respectively.

Similarly, straw yields were 4·8, 7·0,

5·7 and 7·4 t/ha. None of the differences

in yield was statistically significant.
Reassessing Henry Carey (1793–1879): The Problems of Writing Political Economy in Nineteenth-Century America
Authors: DAWSON ANDREW
Published: July 2002

In April 1859 a group of well-to-do manufacturers and Republican
politicians coaxed a reclusive Henry Carey, Philadelphia's pre-eminent
economist, from his study to a public dinner in his honour.
One hundred and twenty five names were at the foot of an invitation to dine at the
opulent La Pierre Hotel in recognition of Carey's “service in behalf of American industrial interests.” The banqueting hall glittered with
brilliantly illuminated chandeliers trimmed with floral arrangements; at
one end a banner proclaimed “Protection to American Labor,” although,
curiously, none of the guests looked as though they actually laboured;
strung across the other end of the hall another banner blazoned
“Harmony of Interests,” but only one interest sat at table. These two
slogans encapsulate Carey's world view. He had a vision of an ideal
America in which small manufacturing towns would spread across the
land. To him “association ” allowed farmers to exchange products with
neighbouring mechanics and to develop America beyond the stage of
primary producer. Towns would grow into cities, generate a social and
cultural life, and cities would trade with other cities. By such a process all
underdeveloped nations would achieve economic maturity. Through the
free association of co-operating individuals, town and country and capital
and labour achieved harmony. The only way to overcome the baneful
effect of British imperialism was through the protective tariff. To Carey's
way of thinking, free trade was the antithesis of association because it
created “centralization,” a system in which a core industrial capitalism
traded manufactures for raw materials with a faraway and less developed
periphery. Trading at such a distance allowed a merchant class to
intervene and siphon off the hard-won efforts of labour. Free trade led to
wild, speculative fluctuations in economic activity, periodic overproduction as consumers were not matched by producers, and long-term
underdevelopment of the agricultural regions of the American South and
West which lay outside the orbit of north-eastern manufacturers. Carey's
ripened theoretical position was consequent upon the enormous changes
experienced by American society during the decades of the 1830s, 40s and
50s. Like all utopias, the future was intimately linked to the hopes and
fears of the present. To the growing but still subaltern class of
manufacturers that rubbed shoulders at La Pierre's dinner tables, he
offered a comforting vision of American small-town life as an antidote to
the reality of British social polarization and class conflict.
A STUDY OF RISK FACTORS FOR INTESTINAL HELMINTH INFECTIONS USING EPIDEMIOLOGICAL AND ANTHROPOLOGICAL APPROACHES
Authors: OLSEN A. , SAMUELSEN H. , ONYANGO-OUMA W.
Published: July 2002

This study, conducted in Kisumu District, Kenya, identified important risk factors for infection with intestinal helminths using traditional epidemiological methods. This was combined with a rapid assessment study using qualitative methods, which focused on sanitation practices and local illness perceptions. The multiple logistic regression analysis revealed that the absence of latrines was a significant predictor for hookworm infection with an odds ratio (OR) of 1·9. The analysis also revealed that households without soap had a 2·6 times higher risk of being infected with Ascaris lumbricoides compared with households where soap was available, and that the number of inhabitants living in a household was a significant predictor for infections with hookworms (OR=3.2). Furthermore, the presence of children of 5 years and under in the household was a predictor for infection with A. lumbricoides (OR=2.7), while the absence of this age group was a predictor for hookworm infection (OR=3.8). The qualitative part of the study revealed that people did not consider worms as a serious health threat, but as a nuisance. Among the population, latrines were seen as beneficial because they were believed to prevent disease, to provide privacy and to keep the environment free of faeces. Handwashing was done many times a day but usually not with soap, which was mainly used when bathing or washing the whole body. Many inhabitants in a household or the presence of children of 5 years and under were never mentioned as being a disadvantage, and these elements would therefore be difficult to include in a control strategy. Since the lack of latrines and of soap were identified as risk factors for infection, while latrines, soap and medicine were seen as assets by the population, it is suggested that helminth control interventions should be concentrated within these areas in this particular society.
DNA fingerprinting of thermophilic lactic acid bacteria using repetitive sequence-based polymerase chain reaction
Authors: DE URRAZA PATRICIO J. , GÓMEZ-ZAVAGLIA ANDREA , LOZANO MARIO E. , ROMANOWSKI VICTOR , DE ANTONI GRACIELA L.
Published: July 2002

DNA fingerprints of lactic acid bacteria were generated by polymerase
chain reaction using a primer based on the repetitive elements found in the genome
of Streptococcus pneumoniae (BOX-PCR). The method made it possible to identify 37
isolates from raw milk, industrial starters and yogurt. Differentiation at species,
subspecies and strain level was possible for Lactobacillus delbrueckii subsp. lactis, Lb.
delbrueckii subsp bulgaricus and Str. thermophilus. BOX-PCR was also applied to
studying the strain composition of a starter culture and the direct detection of strains
in commercial fermented milk.
Gelation of casein-whey mixtures: effects of heating whey proteins alone or in the presence of casein micelles
Authors: SCHORSCH CATHERINE , WILKINS DEBORAH K. , JONES MALCOLM G. , NORTON IAN T.
Published: July 2002

The aim of the present work was to investigate the role of whey protein denaturation on the acid induced gelation of casein. This was studied by determining the effect of whey protein denaturation both in the presence and absence of casein micelles. The study showed that milk gelation kinetics and gel properties are greatly influenced by the heat treatment sequence. When the whey proteins are denatured separately and subsequently added to casein micelles, acid-induced gelation occurs more rapidly and leads to gels with a more particulated microstructure than gels made from co-heated systems. The gels resulting from heat-treatment of a mixture of pre-denatured whey protein with casein micelles are heterogeneous in nature due to particulates formed from casein micelles which are complexed with denatured whey proteins and also from separate whey protein aggregates. Whey proteins thus offer an opportunity not only to control casein gelation but also to control the level of syneresis, which can occur.
15N enrichments of casein and plasma protein amino acids in cows
ingesting 15N-labelled ammonium sulphate
Authors: CASSERON FLORENCE , RYCHEN GUIDO , RUBERT-ALEMAN XIMO , MARTIN GERARD JEAN , LAURENT FRANÇOIS
Published: July 2002

The aim of this work was to determine by ion-exchange liquid
chromatography and isotope ratio mass spectrometry the specific
15N enrichment of
amino acids in casein and plasma proteins in cows receiving three successive daily
oral doses (300, 150 and 150 g) of
(15NH4)2SO4 (10 atom per cent
isotopic enrichment) and to examine the
15N enrichments obtained with regard to nitrogen transport and
metabolism in the lactating cow. To investigate the
15N distribution in amino acids
in casein and in plasma proteins, samples of
15N-labelled casein and plasma proteins
were extracted either from a pool of several milkings (36–96 h
after starting to
administer the tracer) or from pooled venous blood (removed on the fourth day after
the start of administration) from the four lactating cows.
15N enrichments of the
proteins studied, expressed as atoms percent excess, were
0·2509 for casein and
0·0577 for plasma protein. Chromatographic fractionation
of the amino acid mixture
(protein hydrolysates) resulted in nine groups containing between one and four
amino acids: Asp, Ser and Thr; Glu; Pro; Gly, Ala, Val and Met; Ileu and Leu; Tyr;
Phe; His and Lys; and Arg. High
15N incorporation was demonstrated in all
individual or groups of amino acids studied. In both proteins, Glu
appeared to be the
most enriched amino acid, Phe and Arg the least enriched. Most aliphatic molecules
with a single amino group were highly enriched. The much lower
(3·5–7·7-fold)
enrichments in plasma protein compared with casein suggest considerable
intracellular dilution at the site of liver protein synthesis.
Finally, the amino acid
separation methods are discussed and suggestions for improving them considered.
Growth of Debaryomyces hansenii on a bacterial surface-ripened soft cheese
Authors: LECLERCQ-PERLAT MARIE-NOELLE , OUMER ABDELGHANI , BERGERE JEAN-LOUIS , SPINNLER HENRY-ERIC , CORRIEU GEORGES
Published: July 2002

Experimental cheeses were prepared in triplicate from pasteurized milk
inoculated with Debaryomyces hansenii under aseptic conditions. Three cheesemaking
replicates, with efficient control of environmental parameters (temperature, relative
humidity, atmospheric composition) showed similar ripening characteristics. Deb.
hansenii grew only on the cheese surface, where its oxygen demand was satisfied,
especially during the first 24 h (mean generation time, 5·8 h). Salting in a sterile
saturated brine solution reduced its growth and decreased viability. Growth was
slower after 48 h because of the decrease in ripening temperature (mean generation
time, 94 h). The total count of Deb. hansenii was maximum
(≈3×107 yeasts/mm2) after 6 d ripening and
its viable cell concentration was ≈2×106cfu/mm2. This
difference was due to the ‘non-viability’ of part of the population. The viable
Deb. hansenii concentration was highly correlated
(r2>0·95) with the lactate concentration in the
inner part and with the surface and inner lactose concentrations, up
to day 10 of ripening. This emphasized the importance of the diffusion of carbon
substrate from the inner part to the surface of the cheese during ripening. The pH
of the inner part depended significantly on the lactate and lactose concentrations.
Surface pH was significantly related to inner lactate concentration, temperature and
relative humidity. This also demonstrated the controlling role of carbon source
diffusion.
Effects of calcium soaps of rapeseed fatty acids and protected
methionine on milk yield and composition in dairy cows
Authors: KOWALSKI ZYGMUNT M. , PISULEWSKI PAWEŁ M. , SPANGHERO MAURO
Published: July 2002

The objective of this study was to determine the effects of supplementing
the diets of dairy cows with Ca soaps of rapeseed fatty acids (CSRFA) and rumen-protected (RP) methionine on their milk yield and composition, including milk
protein fractions and fatty acids. Twelve Polish Red Lowland cows were used in a
complete balanced two period changeover experiment. The four treatment diets were
a control consisting of a total mixed ration of grass silage and concentrates, and the
total mixed ration supplemented with RP methionine, CSRFA or RP methionine
plus CSRFA. Dry matter intake was not affected by diet. Milk yield increased when
cows were given the diet with CSRFA, but supplementation of diets with RP
methionine did not affect milk yield. Milk protein content, but not milk protein yield,
decreased when CSRFA was given. The addition of RP methionine to the control diet
and the CSRFA diet produced similar increases in the milk protein content.
Supplementation of the diet with CSRFA significantly changed the milk fatty acid
profile: the proportions of 10:0, 12:0, 14:0, 15:0 and 16:0 in milk fat decreased, but
those of 18:0 and cis-18:1 increased. We conclude that CSRFA can be used in
practical dairy diets to increase milk yield and manipulate its fatty acid composition.
Lubrication theory in highly compressible porous media: the mechanics of skiing, from red cells to humans
Authors: FENG J. , WEINBAUM S.
Published: July 2002

A generalized lubrication theory that is applicable to highly deformable porous layers
is developed using an effective-medium approach (Brinkman equation). This theory
is valid in the limit where the structure is so compressible that the normal forces
generated by elastic compression of the fibres comprising the solid phase are negligible
compared to the pressure forces generated within the porous layer. We assume that
the deformation of the solid phase is primarily due to boundary compression as
opposed to the motion of the fluid phase. A generalized Reynolds equation is derived
in which the spatial variation of the Darcy permeability parameter,
α = H/√Kp, due
to the matrix compression is determined by new local hydrodynamic solutions for the
flow through a simplified periodic fibre model for the deformed matrix. Here H is
the undeformed layer thickness and Kp the Darcy permeability. This simplified model
assumes that the fibres compress linearly with the deformed gap height in the vertical
direction, but the fibre spacing in the horizontal plane remains unchanged. The model
is thus able to capture the essential nonlinearity that results from large-amplitude
deformations of the matrix layer.

The new theory shows that there is an unexpected striking similarity between the
gliding motion of a red cell moving over the endothelial glycocalyx that lines our
microvessels and a human skier or snowboarder skiing on compressed powder. In
both cases one observes an order-of-magnitude compression of the matrix layer when
the motion is arrested and predicts values of α that are of order 100. In this large-α
limit one finds that the pressure and lift forces generated within the compressed
matrix are four orders-of-magnitude greater than classical lubrication theory. In the
case of the red cell these repulsive forces may explain why red cells do not experience
constant adhesive molecular interactions with the endothelial plasmalemma, whereas
in the case of the skier or snowboarder the theory explains why a 70 kg human can
glide through compressed powder without sinking to the base as would occur if the
motion is arrested. The principal difference between the tightly fitting red cell and
the snowboarder is the lateral leakage of the excess pressure at the edges of the
snowboard which greatly diminishes the lift force. A simplified axisymmetric model is
presented for the red cell to explain the striking pop out phenomenon in which a red
cell that starts from rest will quickly lift off the surface and then glide near the edge
of the glycocalyx and also for the unexpectedly large apparent viscosity measured by
Pries et al. (1994) in vivo.
Droplet deformation in dispersions with unequal viscosities and zero interfacial tension
Authors: WETZEL ERIC D. , TUCKER CHARLES L.
Published: July 2002

An analytical model is presented for the deformation of an ellipsoidal Newtonian
droplet, suspended in another Newtonian fluid with different viscosity and zero
interfacial tension. The theory is exact for any linear velocity field, and is not limited
to small deformations. It encompasses some well-known special cases, such as Jeffery's
equation for solid axisymmetric particles and Taylor's small-deformation theory for
droplets. Example calculations exhibit droplet stretching, reorientation, and tumbling,
and provide a reasonable match to available experimental data on transient and
steady droplet shapes. The corresponding rheological theory for dilute dispersions
is also derived, in a form that explicitly includes the effects of microstructure on
dispersion rheology.
Experimental and numerical investigation of an axisymmetric supersonic jet
Authors: MATÉ B. , GRAUR I. A. , ELIZAROVA T. , CHIROKOV I. , TEJEDA G. , FERNÁNDEZ J. M. , MONTERO S.
Published: July 2002

A comprehensive study of a steady axisymmetric supersonic jet of CO2, including
experiment, theory, and numerical calculation, is presented. The experimental part,
based on high-sensitivity Raman spectroscopy mapping, provides absolute density
and rotational temperature maps covering the significant regions of the jet: the zone
of silence, barrel shock, Mach disk, and subsonic region beyond the Mach disk. The
interpretation is based on the quasi-gasdynamic (QGD) system of equations, and
its generalization (QGDR) considering the translational–rotational breakdown of
thermal equilibrium. QGD and QGDR systems of equations are solved numerically
in terms of a finite-difference algorithm with the steady state attained as the limit
of a time-evolving process. Numerical results show a good global agreement with
experiment, and provide information on those quantities not measured in the experiment,
like velocity field, Mach numbers, and pressures. According to the calculation
the subsonic part of the jet, downstream of the Mach disk, encloses a low-velocity
recirculation vortex ring.
Three-dimensional aspects of nonlinear stratified flow over topography near the hydrostatic limit
Authors: AKYLAS T. R. , DAVIS KEVIN S.
Published: July 2002

Steady, finite-amplitude internal-wave disturbances, induced by nearly hydrostatic
stratified flow over locally confined topography that is more elongated in the spanwise
than the streamwise direction, are discussed. The nonlinear three-dimensional
equations of motion are handled via a matched-asymptotics procedure: in an ‘inner’
region close to the topography, the flow is nonlinear but weakly three-dimensional,
while far upstream and downstream the ‘outer’ flow is governed, to leading order,
by the fully three-dimensional linear hydrostatic equations, subject to matching conditions
from the inner flow. Based on this approach, non-resonant flow of general
(stable) stratification over finite-amplitude topography in a channel of finite depth
is analysed first. Three-dimensional effects are found to inhibit wave breaking in
the nonlinear flow over the topography, and the downstream disturbance comprises
multiple small-amplitude oblique wavetrains, forming supercritical wakes, akin to the
supercritical free-surface wake induced by linear hydrostatic flow of a homogeneous
fluid. Downstream wakes of a similar nature are also present when the flow is uniformly
stratified and resonant (i.e. the flow speed is close to the long-wave speed of
one of the modes in the channel), but, in this instance, they are induced by nonlinear
interactions precipitated by three-dimensional effects in the inner flow and are
significantly stronger than their linear counterparts. Finally, owing to this nonlinear-interaction mechanism, vertically unbounded uniformly stratified hydrostatic flow
over finite-amplitude topography also features downstream wakes, in contrast to the
corresponding linear disturbance that is entirely locally confined.
Simulation of normal vortex–cylinder interaction in a viscous fluid
Authors: GOSSLER A. A. , MARSHALL J. S.
Published: July 2002

A computational study of three-dimensional vortex–cylinder interaction is reported
for the case where the nominal orientation of the cylinder axis is normal to the vortex
axis. The computations are performed using a new tetrahedral vorticity element
method for incompressible viscous fluids, in which vorticity is interpolated using a
tetrahedral mesh that is refit to the Lagrangian computational points at each timestep.
Fast computation of the Biot-Savart integral for velocity is performed using a box-point multipole acceleration method for distant tetrahedra and Gaussian quadratures
for nearby tetrahedra. A moving least-square method is used for differentiation,
and a flux-based vorticity boundary condition algorithm is employed for satisfaction
of the no-slip condition. The velocity induced by the primary vortex is obtained
using a filament model and the Navier–Stokes computations focus on development
of boundary-layer separation from the cylinder and the form and dynamics of the
ejected secondary vorticity structure. As the secondary vorticity is drawn outward
by the vortex-induced flow and wraps around the vortex, it has a substantial effect
both on the essentially inviscid flow field external to the boundary layer and on
the cylinder surface pressure field. Cases are examined with background free-stream
velocity oriented in the positive and negative directions along the cylinder axis, with
free-stream velocity normal to the cylinder axis, and with no free-stream velocity.
Computations with no free-stream velocity and those with free-stream velocity tangent
to the cylinder axis exhibit similar secondary vorticity structures, consisting of a vortex
loop (or hairpin) that wraps around the primary vortex and is attached to the cylinder
boundary layer at two points. Computations with free-stream velocity oriented normal
to the cylinder axis exhibit secondary vorticity structure of a markedly different
character, in which the secondary eddy remains close to the cylinder boundary and
has a quasi-two-dimensional form for an extended time period.
Theoretical and numerical study of a
symmetrical triple flame using the parabolic
flame path approximation
Authors: GHOSAL SANDIP , VERVISCH LUC
Published: July 2002

In non-premixed turbulent combustion the reactive zone is localized at the
stoichiometric surfaces of the mixture and may be locally approximated by a diffusion flame.
Experiments and numerical simulations reveal a characteristic structure at the edge
of such a two-dimensional diffusion flame. This ‘triple flame’ or ‘edge flame’ consists
of a curved flame front followed by a trailing edge that constitutes the body of
the diffusion flame. Triple flames are also observed at the edge of a lifted laminar
diffusion flame near the exit of burners. The speed of propagation of the triple flame
determines such important properties as the rate of increase of the flame surface in
non-premixed combustion and the lift-off distance in lifted flames at burners. This
paper presents an approximate theory of triple flames based on an approximation
of the flame shape by a parabolic profile, for large activation energy and low but
finite heat release. The parabolic flame path approximation is a heuristic approximation
motivated by physical considerations and is independent of the large activation
energy and low heat release assumptions which are incorporated through asymptotic
expansions. Therefore, what is presented here is not a truly asymptotic theory of triple
flames, but an asymptotic solution of a model problem in which the flame shape is
assumed parabolic. Only the symmetrical flame is considered and Lewis numbers are
taken to be unity. The principal results are analytical formulas for the speed and
curvature of triple flames as a function of the upstream mixture fraction gradient in
the limit of infinitesimal heat release as well as small but finite heat release. For given
chemistry, the solution provides a complete description of the triple flame in terms of
the upstream mixture fraction gradient. The theory is validated by comparison with
numerical simulation of the primitive equations.
One-dimensional nonlinear stability of pathological detonations
Authors: SHARPE GARY J. , FALLE S. A. E. G.
Published: July 2002

In this paper we perform high-resolution one-dimensional time-dependent numerical
simulations of detonations for which the underlying steady planar waves are of the
pathological type. Pathological detonations are possible when there are endothermic
or dissipative effects in the system. We consider a system with two consecutive
irreversible reactions A→B→C, with an Arrhenius form of the reaction rates and
the second reaction endothermic. The self-sustaining steady planar detonation then
travels at the minimum speed, which is faster than the Chapman–Jouguet speed,
and has an internal frozen sonic point at which the thermicity vanishes. The flow
downstream of this sonic point is supersonic if the detonation is unsupported or
subsonic if the detonation is supported, the two cases having very different detonation
wave structures. We compare and contrast the long-time nonlinear behaviour of the
unsupported and supported pathological detonations. We show that the stability
of the supported and unsupported steady waves can be quite different, even near
the stability boundary. Indeed, the unsupported detonation can easily fail while the
supported wave propagates as a pulsating detonation. We also consider overdriven
detonations for the system. We show that, in agreement with a linear stability analysis,
the stability of the steady wave is very sensitive to the degree of overdrive near the
pathological detonation speed, and that increasing the overdrive can destabilize the
wave, in contrast to systems where the self-sustaining wave is the Chapman–Jouguet
detonation.
On the spreading mechanism of the three-dimensional turbulent wall jet
Authors: CRAFT T. J. , LAUNDER B. E.
Published: July 2002

The paper explores, using different levels of turbulence closure, the computed behaviour
of the three-dimensional turbulent wall jet in order to determine the cause
of the remarkably high lateral rates of spread observed in experiments. Initially, to
ensure accurate numerical solution, the equations are cast into the form appropriate
to a self-similar shear flow thereby reducing the problem to one of two independent
variables.

Our computations confirm that the strong lateral spreading arises from the creation
of streamwise vorticity, rather than from anisotropic diffusion. The predicted ratio of
the normal to lateral spreading rates is, however, very sensitive to the approximation
made for the pressure–strain correlation. The version that, in other flows, has led to
the best agreement with experiments again comes closest in calculating the wall jet,
although the computed rate of spread is still some 50% greater than in most of the
measurements. Our subsequent calculations, using a forward-marching scheme show
that, because of the strong coupling between axial and secondary flow, the flow takes
much longer to reach its self-preserving state than in a two-dimensional wall jet. Thus,
it appears very probable that none of the experimental data are fully developed.
Two-dimensional viscous gravity currents flowing over a deep porous medium
Authors: ACTON JAMES M. , HUPPERT HERBERT E. , WORSTER M. GRAE
Published: July 2002

The spreading of a two-dimensional, viscous gravity current propagating over and
draining into a deep porous substrate is considered both theoretically and experimentally.
We first determine analytically the rate of drainage of a one-dimensional layer
of fluid into a porous bed and find that the theoretical predictions for the downward
rate of migration of the fluid front are in excellent agreement with our laboratory
experiments. The experiments suggest a rapid and simple technique for the determination
of the permeability of a porous medium. We then combine the relationships
for the drainage of liquid from the current through the underlying medium with a
formalism for its forward motion driven by the pressure gradient arising from the
slope of its free surface. For the situation in which the volume of fluid V fed to the
current increases at a rate proportional to t3, where t is the time since its initiation,
the shape of the current takes a self-similar form for all time and its length is proportional
to t2. When the volume increases less rapidly, in particular for a constant
volume, the front of the gravity current comes to rest in finite time as the effects of
fluid drainage into the underlying porous medium become dominant. In this case, the
runout length is independent of the coefficient of viscosity of the current, which sets
the time scale of the motion. We present numerical solutions of the governing partial
differential equations for the constant-volume case and find good agreement with our
experimental data obtained from the flow of glycerine over a deep layer of spherical
beads in air.
Organized motions in a jet in crossflow
Authors: RIVERO A. , FERRÉ J. A. , GIRALT FRANCESC
Published: July 2002

An experimental study to identify the structures present in a jet in crossflow has
been carried out at a jet-to-crossflow velocity ratio U/Ucf = 3.8
and Reynolds number Re = UcfD/v = 6600.
The hot-wire velocity data measured with a rake of eight X-wires at x/D = 5 and 15 and
flow visualizations using planar laser-induced
fluorescence (PLIF) confirm that the well-established pair of counter-rotating vortices
is a feature of the mean field and that the upright, tornado-like or Fric's vortices
that are shed to the leeward side of the jet are connected to the jet flow at the core.
The counter-rotating vortex pair is strongly modulated by a coherent velocity field
that, in fact, is as important as the mean velocity field. Three different structures –
folded vortex rings, horseshoe vortices and handle-type structures – contribute to this
coherent field. The new handle-like structures identified in the current study link the
boundary layer vorticity with the counter-rotating vortex pair through the upright
tornado-like vortices. They are responsible for the modulation and meandering of
the counter-rotating vortex pair observed both in video recordings of visualizations
and in the instantaneous velocity field. These results corroborate that the genesis
of the dominant counter-rotating vortex pair strongly depends on the high pressure
gradients that develop in the region near the jet exit, both inside and outside the
nozzle.
Stability of slender liquid bridges subjected to axial

flows
Authors: LOWRY BRIAN J. , STEEN PAUL H.
Published: July 2002

Experiments document the influence of flow on the

Plateau–Rayleigh (PR) instability of a near-cylindrical liquid

bridge. The slightly heavy bridge is subjected to a surrounding pipe

flow from bottom to top. Linear and nonlinear regimes of response are

reported. Islands of stability in flow rate are observed; that is,

there are bridges that are stable with flow but otherwise not.

Density imbalance and flow each, on its own, is destabilizing but

together they are stabilizing as recorded by a variety of measures.

This nonlinear stabilization is explained in terms of the

codimension-2 nature of the pitchfork bifurcation of the

‘perfect’ Plateau–Rayleigh instability.
The interaction of a point vortex with a

wall-bounded vortex layer
Authors: ATASSI OLIVER V. , BERNOFF ANDREW J. , LICHTER SETH
Published: July 2002

The interaction of a point vortex with a layer of constant

vorticity, bounded below by a wall and above by an irrotational flow, is

investigated as a model of vortex–boundary layer interaction.

This model calculates both the evolution of the interface

which separates the vortex layer from the irrotational flow and the trajectory
of

the vortex. In order to determine the conditions which lead to sustained
unsteady

interaction, three cases are investigated where the mutual interaction
between the

vortex and interface is initially assumed to be weak. (i)

When a weak point vortex lies

outside the layer, the vortex moves with a horizontal speed

that is small relative to the

long-wave phase speed of interfacial waves. A uniformly valid solution
is found for

the interface evolution. This solution shows that for long times

the interface and the

vortex approach an equilibrium state. (ii) When a weak vortex lies inside
the layer,

the vortex is convected by the mean flow and moves with a horizontal speed
which

matches the phase speed of an interfacial wave. This results in a strong
interaction

between the vortex and the interfacial wave. On the interface, a monochromatic

wavetrain forms upstream of the vortex and acts to attract or repel the
point vortex.

The displacement of the vortex due to the wavetrain results in the modulation
of the

amplitude and wavelength of the wavetrain. If the point vortex is attracted
toward

the interface the horizontal speed of the vortex slows and

disturbances directly above

the vortex focus and grow leading to the ejection of vorticity. (iii) When
the point

vortex lies close to the wall and it is sufficiently strong it propagates

downstream with

a large horizontal velocity. In this case, the amplitude of the

interfacial disturbance is

independent of the vortex strength. Again, the vortex and the interface
approach an

equilibrium state. The results of this paper indicate that when the horizontal
speed

of the vortex matches the phase speed of the interfacial disturbance,

it is necessary to

account for the vertical displacement of the vortex in order to predict
the behaviour

of vortex–boundary layer interactions.
Diffusion of a passive scalar from a no-slip boundary into a two-dimensional

chaotic advection field
Authors: GHOSH S. , LEONARD A. , WIGGINS S.
Published: July 2002

Using a time-periodic perturbation of a two-dimensional steady
separation bubble on
a plane no-slip boundary to generate chaotic particle trajectories in a
localized region
of an unbounded boundary layer flow, we study the impact of various geometrical

structures that arise naturally in chaotic advection fields on the transport
of a passive
scalar from a local ‘hot spot’ on the no-slip boundary. We
consider here the full
advection-diffusion problem, though attention is restricted to the case
of small scalar
diffusion, or large Péclet number. In this regime, a certain one-dimensional
unstable
manifold is shown to be the dominant organizing structure in the distribution
of the
passive scalar. In general, it is found that the chaotic structures in
the flow strongly
influence the scalar distribution while, in contrast, the flux of passive
scalar from the
localized active no-slip surface is, to dominant order, independent of
the overlying
chaotic advection. Increasing the intensity of the chaotic advection by
perturbing the
velocity field further away from integrability results in more non-uniform
scalar
distributions, unlike the case in bounded flows where the chaotic advection
leads to rapid
homogenization of diffusive tracer. In the region of chaotic particle motion
the scalar
distribution attains an asymptotic state which is time-periodic, with the
period the
same as that of the time-dependent advection field. Some of these results
are understood
by using the shadowing property from dynamical systems theory. The shadowing

property allows us to relate the advection-diffusion solution at large
Péclet numbers
to a fictitious zero-diffusivity or frozen-field solution, corresponding
to infinitely large
Péclet number. The zero-diffusivity solution is an unphysical quantity,
but is found
to be a powerful heuristic tool in understanding the role of small scalar
diffusion. A
novel feature in this problem is that the chaotic advection field is adjacent
to a no-slip
boundary. The interaction between the necessarily non-hyperbolic particle
dynamics in
a thin near-wall region and the strongly hyperbolic dynamics in the overlying
chaotic
advection field is found to have important consequences on the scalar distribution;

that this is indeed the case is shown using shadowing. Comparisons are
made throughout
with the flux and the distributions of the passive scalar for the advection-diffusion

problem corresponding to the steady, unperturbed, integrable advection
field.