Characterization of lime mortar additivated with crystallization modifiers

Additivating mortars with crystallization modifiers is a novel approach to mitigate salt crystallization damage in historic masonry. Once verified the effectiveness of crystallization modifiers in bulk solution, the next step consists in verifying whether: (i) modifiers are still effective when mixed in mortar and going through the carbonation process and (ii) modifiers alter any mortar properties which might limit their application. This research addresses these issues for sodium ferrocyanide and borax, modifiers for sodium chloride, and sodium sulfate, respectively. Several experimental techniques have been applied to elucidate these questions. The results show that the selected modifiers are still able to alter the salt crystallization after going through the carbonation process of the mortar. Besides, no major effects of the modifiers on the fresh and hardened mortar properties were observed. It can therefore be concluded that there are no restraints for the future use of these crystallization modifiers in restoration mortars.     

Glass and glass production in the Oman peninsula in antiquity reconsidered – chemical and mineralogical investigation of sands

A batch of green‐ and amber‐coloured glass chunks and unguentaria dating from the first century CE was found in 2007 at Dibba al Hisn, a site on the Arabian Sea coast of the United Arab Emirates (UAE). Its elemental and isotopic composition revealed the glass to be of a previously unknown plant ash glass type, different from known contemporary Roman, Mesopotamian, and Indian glass. The Sr isotopic composition of the glass corresponds to locally available plants, pointing to the possible existence of a first‐century CE local glass production centre. To explore this possibility, sands from around the UAE were analysed to establish their suitability for glass making and correspondence with the Dibba finds. This paper presents the results of the elemental analysis of fourteen sands. The analysis, performed using inductively coupled plasma optical emission spectroscopy (ICP‐OES), revealed all sands to be rich in lime and alumina. X‐ray diffraction revealed the presence of calcite and other carbonate minerals, as well as antigorite and quartz. Comparison of the sand compositions to average first‐century CE non‐Roman glass found at Dibba showed them to be unsuitable as raw material for producing the glass of Dibba. The evidence thus identifies this glass batch as imported, contrary to what was suggested before. This paper also reviews the occurrence of thick‐walled unguentaria in the region.     

Evaluating the Environmental Effects of Agricultural Policy

The fact that agricultural policy decisions can have important environmental consequences has become common knowledge among policy scholars and policy practitioners. This relationship is reflected in the increasingly prominent soil conservation and environmental protection components of the 1985 and 1990 Farm Bills. In debating the value of continuing these provisions in the upcoming reauthorization of this legislation, scholars and politicians alike focus almost exclusively on their water quality benefits. However, the soil conservation components of agricultural policy also may affect air quality significantly. Using multivariate transfer function analysis, we find that implementation of the 1985 Farm Bill's Conservation Reserve Program has improved air quality significantly in that area of the country most plagued by agricultural air pollution.     

The Paradox of Narrowing Wage Differentials and Widening Wage Inequality in Mexico

This article examines the parallel phenomena of narrowing wage differentials among major groups of workers and widening wage inequality in general in Mexico during the 1980s and 1990s. In trying to understand this paradox, it finds that a human-capital model cannot explain wage determination in the 1990s. Although employees with higher skills and education have enjoyed increasingly higher relative returns to their human capital, much of the variance in wages is not attributable to differences in human capital or rates of return. Discriminatory wage policies have combined with policies of trade liberalization to markedly widen the wage gap between lower-paid and higher-paid workers.     

RELIGIOUS LEADERS AS POLICY ADVOCATES: THE YOUNGSTOWN STEEL MILL CLOSING

Religious organizations have always played a major role in the formulations of public policy. In the case of plant closings and mass unemployment, religious organizations have always assumed a leadership role in comforting and caring for workers and families under distress from job loss. Recently, religious organizations have broken from this traditional role to become advocates and actors in the politics of plant closings, economic development, and worker ownership. In this article, the efforts of religious organizations spawned by the closing of Youngstown Sheet and Tube are examined.     

PUBLIC POLICIES FOR COMMUNITIES IN ECONOMIC CRISIS

The 1980's very likely will see a major restructuring of the nation's and the world economy. In the process industries and communities that were the growth centers of previous decades will experience economic crisis. This restructuring—presaged in this country by the decaying productivity of certain basic manufacturing industries—will mean that a number of places can no longer provide sufficient income or Jobs for their people nor maintain the quality of existing public amenities. As this process of disinvestment goes forward, these communities face the challenge of finding new economic and social roles, reducing the impacts of job losses, and maintaining the quality of life within severe fiscal limits.