bluuebunny/crossref_metadata_2025 huggingface dataset:
Deriving Gridded Hourly Rainfall on O‘ahu by Combining Gauge and Radar Rainfall
Authors: Huang Yu-Fen , Tsang Yinphan , Nugent Alison D.
Published: August 2023

High temporal and spatial resolution precipitation datasets are essential for hydrological and flood modeling to assist water resource management and emergency responses, particularly for small watersheds, such as those in Hawai‘i in the United States. Unfortunately, fine temporal (subdaily) and spatial (<1 km) resolutions of rainfall datasets are not always readily available for applications. Radar provides indirect measurements of the rain rate over a large spatial extent with a reasonable temporal resolution, while rain gauges provide “ground truth.” There are potential advantages to combining the two, which have not been fully explored in tropical islands. In this study, we applied kriging with external drift (KED) to integrate hourly gauge and radar rainfall into a 250 m × 250 m gridded dataset for the tropical island of O‘ahu. The results were validated with leave-one-out cross validation for 18 severe storm events, including five different storm types (e.g., tropical cyclone, cold front, upper-level trough, kona low, and a mix of upper-level trough and kona low), and different rainfall structures (e.g., stratiform and convective). KED-merged rainfall estimates outperformed both the radar-only and gauge-only datasets by 1) reducing the error from radar rainfall and 2) improving the underestimation issues from gauge rainfall, especially during convective rainfall. We confirmed the KED method can be used to merge radar with gauge data to generate reliable rainfall estimates, particularly for storm events, on mountainous tropical islands. In addition, KED rainfall estimates were consistently more accurate in depicting spatial distribution and maximum rainfall value within various storm types and rainfall structures.

Significance Statement

The results of this study show the effectiveness of utilizing kriging with external drift (KED) in merging gauge and radar rainfall data to produce highly accurate, reliable rainfall estimates in mountainous tropical regions, such as O‘ahu. The validated KED dataset, with its high temporal and spatial resolutions, offers a valuable resource for various types of rainfall-related research, particularly for extreme weather response and rainfall intensity analyses in Hawai’i. Our findings improve the accuracy of rainfall estimates and contribute to a deeper understanding of the performance of various rainfall estimation methods under different storm types and rainfall structures in a mountainous tropical setting.
Structural Change and Post-Socialist Stratification: Labor Market Transitions in Contemporary Russia
Authors: Gerber Theodore P.
Published: August 2023

In Russia, market transition has led to sweeping structural changes: a long recession, growth of the private sector, expansion of certain branches of the economy and contraction of others, a decrease in average firm size, and regional differentiation in economic performance. These structural changes had important consequences for stratification through their effects on individual labor market outcomes. Analyses of nine types of individual labor market transitions in Russia using 1991–1997 work-history data show that structural location has strong effects. Human capital and membership in the Communist Party of the Soviet Union also influence labor market prospects, but not in ways consistent with general theories about how market transition affects stratification processes. Structural change plays a key role in determining the impact of market reforms on stratification. But market transition produces variable patterns of structural change in different countries and in different regions within a single country. The structural perspective demonstrates why market transition has variable consequences for stratification: Different prior conditions and reform policies produce different patterns of structural change.
Confessional Protest: The Religious Birth of U.S. National Social Movements
Authors: Young Michael P.
Published: August 2023

Western forms of protest were fundamentally altered in the early nineteenth century. Scholars from a “contentious politics” perspective have identified this rupture in protest forms with the emergence of the “national social movement” and explain the rupture as the result of interactions with national states. Scholars from a “life politics” perspective argue that the paradigmatic movements of today have moved beyond the political struggles of the nineteenth century and toward a new form of protest that unfolds within civil society and fuses matters of personal and social change. Protests in the United States in the 1830s, however, raise serious doubts about both of these claims. The first U.S. national social movements were not a heritage of the state and they engaged in a form of life politics. The temperance and antislavery movements emerged in interaction with religious institutions—not state institutions—and pursued goals that mixed personal and social transformation. A cultural mechanism combining the evangelical schemas of public confession and the special sins of the nation launched sustained and interregional protests. The intensive and extensive power of these confessional protests called individual and nation to repent and reform, and mobilized actors and resources within a national infrastructure of religious institutions to challenge drinking and slavery.
How the Civil Rights Movement REVITALIZED LABOR MILITANCY
Authors: Isaac Larry , Christiansen Lars
Published: August 2023

Can newly ascendant social movements revitalize the militant culture of older, institutionalized movements? Recent studies have focused on relations between new ascendant social movements like the civil rights, women's, and peace movements that emerged during the postwar cycle of protest, and therefore have been unable to address this question. Focusing on revitalization as a qualitatively different form of intermovement relation, the authors examine the possibility that civil rights movement insurgencies and organizations revitalized workplace labor militancy during the postwar decades. Time-series models show that the civil rights movement fueled an expanded militant worker culture that challenged management and sometimes union leadership. However, this revitalization of labor militancy was contingent on institutional context (stronger in the public sector than the private sector) and form of insurgent action (protests, riots, organizations) differentially embedded in historical phases (civil rights versus Black Power) of movement development. Theoretical implications for the study of social movements, industrial relations, and class conflict are discussed.
Identifying the Unprecedented: Hannah Arendt, Totalitarianism, and the Critique of Sociology
Authors: Baehr Peter
Published: August 2023

How does one identify a phenomenon as radically new or “unprecedented”? Do, in fact, “unprecedented” phenomena exist at all, as presumably some degree of continuity marks every state of affairs? If, however, the idea of continuity is taken too far, are we not at risk of domesticating a radical tendency by conceptually transmuting it into something that is already known? These questions are of pressing importance since September 11th, as commentators warn that America and its allies face radically new enemies in the guise of “rogue” states, movements, and terrorist organizations. Yet sociology has had to grapple with similar issues before. In the 1930s and 1940s, the consolidation of fascist and Nazi movements also taxed sociological understanding and competence to the maximum. This article describes aspects of American sociology's response to that earlier challenge, contrasting it with the approach of Hannah Arendt, who condemned the discipline for systematically failing to appreciate the uniqueness, enormity, and gravity of the events that assailed the epoch. Arendt's critique of sociological methods is followed by a case study—Theodore Abel's investigation into National Socialism—that lends some credence to her misgivings. The work of other sociologists of this period—notably, Talcott Parsons's—is also briefly considered. The concluding section of the paper examines the theoretical problems involved in seeking to conceptualize an “unprecedented” event (movement, institution).
The Use of Standardized Solutions Instead of Individualized Prescriptions for Parenteral Nutrition on the Neonatal Intensive Care Unit in UZ Brussel: A Feasibility Study
Authors: Batteux Melanie , Meers Garmt , Fien Bockstal , Cortoos Pieter-Jan , Cools Filip
Published: August 2023

For parenteral nutrition (PN) of newborns, the European Society for Paediatric Gastroenterology Hepatology and Nutrition (ESPGHAN) 2018 guidelines recommend standardized solutions over individual PN (IPN) solutions for most patients. This retrospective study assessed if a shift from IPN to standardized PN was feasible at the UZ Brussel. Using prescription data of 145 neonates, we calculated the nutrient provision for IPN and for standardized PN of the same volumes. We compared the macronutrient intakes with ESPGHAN 2018 recommendations to assess the feasibility. For neonates of a gestational age (GA) <32 or >36 weeks, standardized PN reached recommendations as least as fast as IPN. For neonates with a GA of 32 to 36 weeks, the administration protocol requires further adjustments as amino acid provision was lacking compared to IPN. Overall, the results support the feasibility of a shift from IPN to standardized PN at the UZ Brussel.
What is to be Done? How Radical Leftists Help to Solve the Problem of Personalist Party-Building in Latin America
Authors: Resmini Fabio , Abbott Jared
Published: August 2023

Political leaders around the world increasingly rely on personalist parties to win elections and govern. While existing scholarship assumes that personalist parties do not build territorial organization, in fact they vary substantially in terms of organizational strength. In this paper, we move beyond existing structural explanations of party-building and focus on the role of party elites’ preferences to explain the source of this variation. Through a mixed-method approach combining process-tracing of the case studies of Venezuela’s MVR/PSUV and Ecuador’s Alianza PAIS and statistical analysis of Latin American parties, we find that party elites’ past political experiences shape whether personalist parties successfully invest in party organization. Party officials who were socialized in radical-left parties are more likely to advocate for party-building and their presence within party cadres is associated with stronger party organization.
Farewell to genre: Plot, meaning, and eudaemonic paths in social narratives
Authors: Madigan Todd
Published: August 2023

Narratives, it has been argued, serve to represent, explain, transform, and even constitute the social world. However, efforts to apply narrative theory to the social world have become mired in conceptual ambiguity. The culprit of much of this confusion is the notion of genre, which, as a formal property of social narratives, has become hopelessly confused. Instead, when the study of the social world turns to the formal elements of plot structure, I argue that the analysis of how a protagonist’s state of well-being is emplotted is a far more helpful analytic frame. To this end, I delineate a typology of narratives based on what I call their eudaemonic path (the Greek term eudaemonia capturing the concept of ‘well-being’ more fully than the term happiness) and conclude that eudaemonic paths provide explanatory insight regarding the content that is selected for and omitted from particular social narratives. And it is on this more certain foundation – rather than the slippery footing of so-called genre – that the formal elements of narrative can be said to influence social action and cultural change.
ISMP Medication Error Report Analysis
Authors: Cohen Michael R.
Published: August 2023

These medication errors have occurred in health care facilities at least once. They will happen again—perhaps where you work. Through education and alertness of personnel and procedural safeguards, they can be avoided. You should consider publishing accounts of errors in your newsletters and/or presenting them in your inservice training programs.

Your assistance is required to continue this feature. The reports described here were received through the USP Medication Errors Reporting Program (MERP), which is presented in cooperation with the Institute for Safe Medication Practices. If you have encountered medication errors and would like to report them, you may call USP toll-free, 24 hours a day, at 800-233-7767 (800-23-ERROR).

Any reports published by ISMP will be anonymous. Comments are also invited; the writers’ names will be published if desired. ISMP may be contacted at the address shown below.

Errors, close calls, or hazardous conditions may be reported through the ISMP ( www.ismp.org ) or USP ( www.usp.org ) Web sites or communicated directly to ISMP by calling 800-FAIL-SAFE or via E-mail at ismpinfo@ismp.org . ISMP guarantees the confidentiality and security of the information received and respects reporters’ wishes as to the level of detail included in publications.
Cancer Chemotherapy Update
Authors: Waddell J. Aubrey , Solimando Dominic A.
Published: August 2023

The increasing complexity of cancer chemotherapy heightens the requirement that pharmacists be familiar with these highly toxic agents. This column will review various issues related to preparation, dispensing, and administration of cancer chemotherapy. It will also serve as a review of various agents, both commercially available and investigational, used to treat malignant diseases. Questions or suggestions for topics should be addressed to Dominic A. Solimando, Jr., President, Oncology Pharmacy Services, Inc., 4201 Wilson Boulevard #110-545, Arlington, VA 22203, E-mail: OncRxSvc@aol.com ; or J. Aubrey Waddell, Associate Professor, University of Tennessee College of Pharmacy; Oncology Pharmacist, Pharmacy Department, Blount Memorial Hospital, 907 East Lamar Alexander Parkway, Maryville, TN 37804; E-mail: waddfour@charter.net .
Safety Issues: Use of Continuous Subcutaneous Insulin Infusion (CSM) Pumps in Hospitalized Patients
Authors: Dalton Mazie F. , Klipfel Laurie , Carmicbael Kim
Published: August 2023

— The use of continuous subcutaneous insulin infusion (CSII) pump therapy is increasing. Patients on CSII at admission whose current admission diagnosis is not expected to affect their blood sugar, who are competent to manage their pumps, and who are in good control of their diabetes at the time of hospital admission may benefit from the good control of continued use of CSII during their stay. However, as with any insulin therapy, CSII can be dangerous if not managed appropriately.

Hospitals should be prepared to safely manage these patients by having protocols in place to carefully select those suitable to continue their pumps and to discontinue CSII when criteria are no longer met. All caregivers of the patient, including physicians, nurses, pharmacists, operating room and emergency staffs, and radiology technicians, must have an appropriate level of education on CSII. Hospitals not prepared to manage these patients may need to consider disconnection of the pump at admission.

There are few publications addressing management of CSII in the hospital setting. We review published reports and describe our approach to the management of CSII during hospitalization that includes: a case analysis of our experiences; the development of a policy and procedure, standardized physician order form, standardized pharmacy order entry, and educational programs for medical, nursing, radiology, and pharmacy staff; and physician credentialing.
Effects of Value-Belief-Norm Theory, ESG, and AI on Space Tourist Behavior for Sustainability With Three Types of Space Tourism
Authors: Kim Myung Ja , Hall C. Michael , Kwon Ohbyung , Sohn Kwonsang
Published: August 2023

Since reusable launch vehicles have revolutionized access to space, space tourism has received enormous policy and research attention. However, such growth is occurring within a wider context of concerns over climate change, emissions, and space debris. Although the space industries have enormous environmental impacts, few studies have been undertaken on the sustainability of space tourism. Therefore, we aim to create and assess an extended value-beliefs-norms theory with environmental, social, and governance (ESG) factors, trust in artificial intelligence (AI), and the benefits of AI, in comparing three types of space tourism (Earth, suborbital, and orbital). To achieve the goals, multi-method analyses of 1,000 respondents were applied, including partial least squares-structural equation modeling, multi-group analysis, fuzzy-set Qualitative Comparative Analysis, and deep learning. Results revealed that the extended value-belief-norm model well explains space tourist behavior, ESG also has significant roles on the research model, and the three types have unique characteristics.
Promoting Innovation or Exacerbating Inequality? Laboratory Federalism and Australian Age Discrimination Law
Authors: Blackham Alysia
Published: August 2023

According to laboratory federalism, federal systems can promote governmental innovation and experimentation, while containing the risks of innovation to only one jurisdiction. However, it is unclear whether these benefits are realised in practice and whether states are actually effective ‘laboratories’. This article evaluates the extent to which laboratory federalism is occurring in practice, focusing on a case study of age discrimination law in Australia. Drawing on related ideas of democratic experimentalism; legal doctrinal analysis of age discrimination law in the Australian states and territories, and at the federal level; and qualitative expert interviews with 66 Australian respondents, I map the potential and limits of laboratory federalism in advancing age equality. I argue that, in this particular context, the benefits of experimentation may be outweighed by the resulting difficulties of enforcing age discrimination law, exacerbating inequality in practice. The federal structure has led to a confused and confusing patchwork of legal regulation. There is therefore a need for stronger federal structures to facilitate mutual learning and better realise the benefits of laboratory federalism.
Adverse childhood experiences and early initiation of substance use: A survival analysis
Authors: Meadows Amy L , Strickland Justin C , Hyder S Maela , Basconi Rita C , Stull Margaret E , Wagner Frances P , Nguyen Mai N , Rayapati Abner O , Rush Craig R
Published: August 2023

Objective

Early adversity, such as adverse childhood experiences (ACEs), is a risk factor for the development of substance use disorder (SUD). ACEs are associated with earlier initiation of substance use. This study examined the relationship between ACEs and age of initiation of substance use using survival analysis. It is hypothesized that individuals with higher ACEs will have an earlier age of initiation.

Method

Participants were recruited from the University of Kentucky's Laboratory for Human Behavioral Pharmacology. Participants were 18 years or older, English speaking, and actively engaged in substance use. Participants were not in substance abuse treatment nor were they seeking treatment. ACE scores were calculated, and age of substance use initiation was recorded. A Cox proportional hazard model was used to examine the effect of ACE score on age of substance use initiation.

Results

A total of 107 participants completed the study. An average number of 2.3 ACEs (SD = 2.2) were endorsed with 24% of participants reporting 4 or more ACEs. Higher ACE scores were associated with cigarette smoking and non-medical prescription opioid use onset ( hazard ratio (HR) = 1.14, 95% CI=1.02–1.28, p = 0.02, and HR=1.19, 95% CI = 1.04–1.37, p = 0.01, respectively.

Conclusions

A significant association was found between higher ACE scores and earlier initiation of cigarette and non-medical prescription opioid use, consistent with prior research. Primary prevention of ACEs, screening for ACEs during childhood, and interventions for ACEs if detected, may help to reduce the risk of substance use/SUD in adulthood.
Improvement master–slave robustly synchronous criteria of uncertain chaotic Lur’e systems via an augmented Lyapunov–Krasovskii functional
Authors: Zhang Chunfu , Sun Yanyan , Duan Wenyong
Published: August 2023

The robust synchronization of uncertain master–slave Lur’e systems based on time-delayed feedback control is further investigated. A less conservative synchronization stability criterion and a less conservative robust synchronization stability criterion than some recent published references are proposed via Lyapunov stability theory. First, an augmented delay-dependent Lyapunov–Krasovskii functional (LKF) is constructed, where some single integral terms are augmented to the integrand component of a single-integral subfunction. This not only increases some coupling information on some system variables but also increases the coupling information on some necessary variables contained in the inequality lemmas, which can make full use of the inequality lemmas and reduce the conservatism of the synchronization stability criterion. Second, to overcome the nonlinear phenomena in the synchronization criterion, the novel negative definite inequality equivalent transformation lemma is used to transform the nonlinear inequalities to the linear matrix inequalities (LMIs) equivalently, which can be easily solved by the MATLAB LMI-Toolbox. Finally, some common numerical examples are presented to show the effectiveness of the proposed approach.
Robust dynamic output feedback predictive control for discrete uncertain systems with time-varying delays
Authors: Wang Shiqi , Li Hui , Li Hua , Shi Huiyuan , Sun Qiubai , Li Ping
Published: August 2023

A robust dynamic output feedback predictive control approach is developed for a discrete system with time-varying delays, unknown external disturbances, and unmeasurable states. First, the discrete system is transformed into an incremental state deviation model. Based on this model, a novel tracking deviation feedback model is established by extending the output tracking error. Then, a robust predictive control law, possessing more degrees of freedom, is designed. The closed-loop model is further given in conjunction with the feedback model. Second, by using the linear matrix inequality (LMI) method, relaxation technique, and variable transformation method, a less conservative stability condition is given in LMI form, which allows the controller to tolerate a greater range of time-varying delays. The gains of the control law are acquired by solving the stability condition, and the control performance can be significantly enhanced. Finally, by utilizing the TTS20 water tank as a simulation case, the viability and effectiveness of the proposed method are demonstrated.
Students with disabilities' perceptions of school climate: A systematic review
Authors: Hunt Steven M. , Radliff Kisha M. , Acton Christopher , Bible Alenna , Joseph Laurice M.
Published: August 2023

School climate has been identified as a critical systemic variable associated with many desirable academic and social-emotional outcomes. However, little research has been conducted regarding the students with disabilities’ perceptions of school climate. This review aimed to investigate and synthesize the existing research on this topic to identify trends in the literature, guide future research, and inform intervention and reform. Following a systematic search of four major databases, 12 studies were determined to meet the inclusion criteria. Generally, students with disabilities reported more negative perceptions of school climate in comparison to peers without disabilities. However, when an intersectional lens was applied to discern this population's perspectives, a more nuanced understanding of school climate was able to be identified. This approach suggests evaluating school climate data in a disaggregated form may better inform decision-making in schools. Future research regarding students with disabilities’ perceptions of school climate and related outcomes is needed. This should include both a wider and more specified sample of students, what school climate subdomains are impacted and how, how these variables relate to school-related outcomes, and how school climate interventions specifically impact students with disabilities.
A Critical Examination of Language Ideologies and Policies in an International School in Colombia
Authors: Bettney Heidt Esther
Published: August 2023

Background:

In recent years, scholars and educators have criticized exclusionary language ideologies and policies within international schools. International schools often emphasize proficiency in English as a language of power instead of valuing students’ and teachers’ dynamic multilingual practices.

Focus of Study:

Although oppressive language ideologies and policies in international schools are a central concern for critical education scholars, relatively little is known about international schools that are negotiating a shift toward more inclusive and equitable approaches. To understand the role of language ideologies and policies within an international school context, I examined the following research question: What language ideologies influence language policy creation and appropriation at Colegio Colombiano (CC)?

Research Design:

To answer this question and further understand the complex and shifting roles of language ideologies and policies within international schools, I conducted a case study at CC, an international school in Colombia.

Data Collection:

Through collaborative research with nine teachers, I examined how teachers engaged with more equitable approaches to multilingual education. I collected and analyzed various types of data, including school language policies, lesson and unit plans, classroom observations, teacher and student interviews, and a teacher questionnaire.

Findings:

Through analyzing the collected data, I found a spectrum of language ideologies and language policies, as many faculty demonstrated a significant shift away from oppressive and exclusionary language ideologies and language policies through an increasing recognition of Spanish. On the other hand, although explicit messages about English as superior were no longer officially promoted, colonialistic ideologies and policies persisted that valorized English, denigrated Spanish, and ignored other societal and home languages. To analyze these findings further, I critically examined the described spectrum of language ideologies and policies through Pennycook’s (2000) framework of language ideologies.

Conclusions:

I conclude with key considerations for educators and researchers across diverse contexts as they critically reconsider and decolonize current approaches to multilingual education.
Network Analysis for Formative Evaluation of Collaborative, Team Science Research Partnerships
Authors: Liu Grace M. , Meadows Meredith L. , Wiley Katherine T. , Jurinsky Jordan , Anglemyer Andrew A. , Wang Lucy L. , Schneider Joseph T. , Suiter Sarah V.
Published: August 2023

Cancer health disparities persist across the cancer care continuum despite decades of effort to eliminate them. Among the strategies currently used to address these disparities are multi-institution research initiatives that engage multiple stakeholders and change efforts. Endemic to the theory of change of such programs is the idea that collaboration—across institutions, research disciplines, and academic ranks—is necessary to improve outcomes. Despite this emphasis on collaboration, however, it is not often a focus of evaluation for these programs and others like them. In this paper we describe a method for evaluating collaboration within the Meharry-Vanderbilt-Tennessee State University Cancer Partnership using network analysis. Specifically, we used network analysis of co-authorship on academic publications to visualize the growth and patterns of scientific collaboration across partnership institutions, research disciplines, and academic ranks over time. We presented the results of the network analysis to internal and external advisory groups, creating the opportunity to discuss partnership collaboration, celebrate successes, and identify opportunities for improvement. We propose that basic network analysis of existing data along with network visualizations can foster conversation and feedback and are simple and effective ways to evaluate collaboration initiatives.
Polyurethane Foams as Solid Sorbents in Separation Science: Recent Advances
Authors: Braun T.
Published: August 2023

During the last decade resilient polyurethane foams and rigid polyurethane microspheres have become established as solid sorbents. This paper presents the basic data on these new sorbents and summarises in tabular form the recent advances published during the last few years.
British Tests and Controls to Limit the Fire Risks of the Contents of Buildings
Authors: Paul K.T.
Published: August 2023

The past decade has seen the rapid development within the UK of tests and performance specifications to determine and/or control the ignition and burning behaviour of upholstered furniture, mattresses and bed assemblies in domestic, public and institutional premises. The test procedures were based on considerable research including full-scale fire tests and field reports. The resultant tests were almost invariably based on composite specimens except where single material tests were sometimes used for quality control work. Early tests were relatively crude ad hoc procedures, but have been progressively refined and developed. British Standard ignition tests for upholstered seating have been published (BS 5852, Parts 1 and 2) and ignition tests for mattresses and bed assemblies, and burning tests for upholstered furniture, mattresses and bed assemblies are being used within industry and government areas. The rapid development of these tests and their application has led to some overlapping, while many tests are currently being revised or replaced. This paper attempts to outline the current ‘state of the art’ within the UK for fire tests for upholstered furniture, mattresses and bed assemblies.
The Contribution of Upholstered Furniture to Residential Fire Risks
Authors: Prager F. H. , Darr W. C. , Wood J. F.
Published: August 2023

The effect of different-intensity ignition sources on the possible contribution of flexible polyurethane foam to the fire risk potential of upholstered furniture is considered. The influence of the filling material, the outer covering, the use of interlayers and the design of the furniture on ignition and burning in laboratory and large-scale tests is studied. From the various upholstery combinations tested the dominating effect of outer coverings and interlayers is demonstrated. The importance of the type and combination of upholstery material to the risk of smoldering ignition and flame spread is also shown. Some of the problems in evaluating smoke and toxicity of the combustion products are discussed. Proposals are made for producing improved material combinations which are more resistant to ignition sources of low and medium intensity.
Rehabilitation of UF-Foamed Plastics
Authors: Baumann Heinz
Published: August 2023

One of the oldest marketable foamed plastics is urea-formaldehyde-foam (UF-foam). It has been argued that the formaldehyde liberated during the curing stage should be reduced. Formaldehyde emission during the solidification of aminoplast precondensates is a common effect and airborne concentrations well above the odour threshold are irritating to the mucosa. Therefore an improved foam formulation was compared with a present standard foam for formaldehyde emission in laboratory experiments, and also in the field. It proved to be feasible to reduce the emission potential such that there was no noticeable ambient concentration.
Effect of Chain Extenders/Crosslinkers on the Compression Behaviour of PU RIM Materials
Authors: Korodi T. , Marcu N. , Tirnaveanu Al.
Published: August 2023

The influence of ethylene glycol, triethanolamine and of a rigid polyol on the compression behaviour of a microcellular elastomer used in RIM technology, has been studied using multiple linear regression analysis. The importance of the above parameters has been established using the statistical Student's test. It has been found that ethylene glycol has the major influence on compression resistance, hysteresis loss and elastomeric softening, while triethanolamine has a less important or negligible influence on these properties.
Cellular Polymers for Medical Use: The Vital Role of Porosity and Permeability
Authors: Boretos John W.
Published: August 2023

Cellular polymers have played a significant role in the development of a base of knowledge for the safe and efficacious use of surgically implantable biomaterials. Inherent compatibility and properties of porosity and permeability are vital attributes for the ingrowth of soft and rigid tissues into select indwelling devices. Such characteristics are necessary for long-term physiological acceptability of vascular grafts and for permanent bone attachment of dental and orthopedic appliances, and for controlled drug release implants. Early experience with sponges of polyvinyl alcohol denatured gelatin collagen and silicone rubber has aided in the establishment of criteria for pore size which have carried over to more recently used foams of polyurethane, polytetrafluoroethylene and polyethylene. Cellular polymers and their composites promise to play an even larger role in health care delivery of the future.
Foams based on Phenolic and Urea-Formaldehyde Resins Mixtures and their Applications for Heat Insulation of Pipelines. 3. Investigation of Physico-Mechanical Properties
Authors: Shutov F.A. , Ivanov V.V.
Published: August 2023

The strength properties of a foam based on a mixture of phenolic and urea-formaldehyde resins are described. The relationship between compressive strength, tensile strength, crack stability, shrinkage, impact strength, water absorption, heat conductivity, dielectric properties and other properties versus apparent density and moisture content, and external temperature are presented. A discussion of actual technical characteristics of foam and the main requirements for heat insulation of metal underground pipes is presented.
Foams Based on Phenolic and Urea-Formaldehyde Resins Mixtures and their Applications for Heat Insulation of Pipelines. 5. Investigation of Ageing of Phenolic Foams during Long-term Exposure to High Temperature
Authors: Shutov F.A. , Ivanov V.V.
Published: August 2023

The specificity of long-term ageing of phenolic foam in the heat insulation of pipe lines is discussed. Apparent density distribution of foam across the thickness of the foam layer affected the service time of foam insulation in real conditions of application. After long-term exposure (up to 4000 h at 100–200° C) compressive strength of foams was studied. Assuming that the time-temperature dependences of foams follow the Arrhenius law, the duration of foam was predicted and compared with experimental data. Thermogravimetric analysis was applied, and kinetic constants of long-term ageing were calculated. Other properties, i.e. electrical properties and water sorption, were also studied.
Foams based on Phenolic and Urea-Formaldehyde Resins Mixtures and their Applications for Heat Insulation of Pipelines. 6. Full-scale Tests and Technico-economic Analysis
Authors: Shutov F.A. , Ivanov V.V.
Published: August 2023

The thermal conductivity and heat flux of phenolic foams applied for insulation of metal pipes were measured, and effectivity of the insulation was estimated at the model conditions. Examinations of real pipelines after many years of application in channelless heat lines were undertaken. It was shown that the developed phenolic foam demonstrated, after six years of application, good stability. Technico-economic analysis of the use of the foam is presented, and comparison with other types of pipe insulation materials is made. The perspectives of developed foams for heat insulation of pipelines are outlined, and further research and applied problems for phenolic foams are formulated and discussed.
Are Foams a Fire Hazard?
Authors: Woolley W.D.
Published: August 2023

Over the last decade growing concern has been voiced about the fire hazards of cellular polymers used in building and transport applications. Some of this concern is justified as illustrated by recent fires and experimental simulations where rapid fire development has occurred with potential for death or injury from the spread of combustion products within very short periods of time.

Many technical difficulties have arisen in the use of synthetic foams. Their introduction has presented problems since the test methods used traditionally to assess performance have been somewhat inadequate to cope effectively with the new properties of polymers and polymer composites.

Major progress is being made in understanding the fire behaviour of cellular polymers. This involves studies of ignitability, flame spread, heat release, and the production of smoke and toxic gases. In parallel to this, important technical advances have been made by industry in the development of new formulations of cellular materials and composites with improved fire behaviour.

It is now time to bring together the current knowledge of all aspects of cellular polymers in fire so that further applications of these materials can continue safely allowing full use of their potential for improving the comfort and efficiency of our lives.

This paper examines the basic problems which have occurred during the use of cellular polymers with regard to fire. Recent fire scenarios which have attracted attention to cellular materials and the ways the hazard is being addressed and mitigated are discussed. To aid this the paper also examines the basic mechanisms of burning of the polymers and the associated hazard to life.

Finally it should be emphasised that much of this paper is directed, intentionally, to understanding circumstances where untoward events may occur to place life in jeopardy. This approach is necessary for the elimination of potentially hazardous situations and to enable the continuing use of cellular polymers in a safe way.
How do Foams Perform under Fire Conditions?
Authors: Troitzsch J. H.
Published: August 2023

The fire performance of foams does not, as often stated, solely depend on the chemical and physical properties of the type of material used. On the contrary, it is determined by many other factors including its form, any interactions with other materials used and the design of the finished product.

In order to obtain a realistic assessment of their fire hazard, it is of prime importance to test the fire performance of finished foam systems under normal operating conditions. Thus, several examples of large-scale fire tests for different foams as parts of roof coverings, external walls and as packaging materials are given. The results show that systems containing these foams do not present an unacceptable fire hazard.
Fire Behaviour of Rigid Foam Insulation Boards
Authors: Briggs P. J.
Published: August 2023

Low density cellular polymers have established a significant share of the market for insulating materials in the building industry due to their unique combination of low density and low thermal conductivity. Manufacturers of rigid foam insulation boards have had to satisfy fire performance criteria required by national standards and by insurance organisations. Since cellular polymers are usually installed behind inorganic or metallic facings, small-scale fire tests are only relevant for development and quality control purposes. The characteristics of the fire behaviour of different rigid foams (i.e. PS, PUR, PIR and PF) are discussed.

Assessment of the potential fire hazard of an insulation board in use requires large-scale testing facilities. Evaluations of roofboard in the Factory Mutual Calorimeter and lining board in Corner Tests, including the FOC Wall and Ceiling Lining Test, are described. By careful material selection and composite engineering, the fire hazard of rigid foam insulation boards in building applications has been significantly reduced.
Shock Mitigation Foams – The Basic Parameters
Authors: Richardson M. O. W. , Nandra D. S.
Published: August 2023

The development of shock absorbing polymer foams requires an appreciation of the complex phenomena involved. Isolation of the main parameters controlling shock mitigating potential is the essential prerequisite to any programme of research, and this paper outlines some of the problems involved. Comment is made on the matrix and structure of foam materials along with a brief survey of the mechanisms of energy dissipation that can operate during impact conditions. Methods of testing are discussed and essential differences between swinging pendulum, free fall and load/compression tests outlined. The role of density/property relationships is highlighted and emphasis given to the importance of incorporating appropriate material factors controlling stiffness, strain dependence and strain rate dependence into any equations used to predict depth of penetration and maximum deceleration of an impacting object.
Load-Deflection Analyses of Shock Mitigating Polyurethane–Silicone Foams
Authors: Richardson M. O. W. , Nandra D. S.
Published: August 2023

Three types of polyurethane-silicone foam are analysed in terms of their compression load-deflection, static load-deflection, recovery time and matrix transition temperature characteristics. The information produced is used to discuss their suitability as shock mitigating helmet liner materials. The rate of deflection during mechanical testing is shown to be highly significant at values <400% min-1 and the compression-deflection ‘plateau’ characteristics analysed in terms of a 10% load differential. Foam type 1085–47 is demonstrated to be of potential use in single impact shock absorption contexts and types 101–38 and 1085–41 of use where repeated impacts are anticipated and there is limited time available for recovery.
Dual Hardness Seating Cushions from a Single Head
Authors: Evans B. E.
Published: August 2023

Dual hardness flexible polyurethane foam cushions are of increasing interest to automotive designers as a means of improving safety and comfort.

Advances in process technology with the use of double or triple mixing heads dispensing foams of differing hardness into a suitably designed mould have led to the production of dual hardness cushions in one operation. ICFs all MDI (diisocyanato diphenylmethane) cold cure foam technology which offers many advantages over TDI/MDI systems (TDI, toluene diisocyanate), is already being used in Europe to produce seats by this method.

More recent developments in this technology and in dispensing equipment designed by Cannon have resulted in the ability to produce dual hardness front seat cushions from a single mixing head dispenser purely by changing isocyanate index.
Halogenated Polyetherpolyol IXOL for Rigid Cellular PUR Materials with Improved Flame Retardancy
Authors: Walch P.
Published: August 2023

The use of rigid PUR foams as insulating materials is becoming more and more accepted in building, transport and industrial fields because of the advantages they have over other materials. However, poly-urethane foams are organic materials and will therefore burn. Use of halogenated polyols like IXOL in lieu of classical polyols in PUR formulations improves the fine properties of these foams.

Results on different fire tests are presented. Trials have been made in realistic configurations, for example full-scale corner tests in order to have a better idea of the flame retardation obtained with IXOL based foams.
Effect of Process Variables on the Foaming of Phenolic Resins
Authors: Vázquez Analía , Williams Roberto J. J.
Published: August 2023

Resols prepared with a formaldehyde/phenol molar ratio equal to 1·5, and different reaction agents, were foamed with the addition of a chlorofluorocarbon blowing agent (R 113), a commercial surfactant, and a mixture of phosphoric and sulphuric acids. The curing of the resol followed second-order kinetics as determined with the adiabatic temperature rise method. Temperature evolution and the expansion rate during the foaming process were predicted by using a thermal energy balance together with constitutive equations for the crosslinking kinetics and the blowing agent solubility. Both the blowing agent and formaldehyde contribute to the foam expansion. Fixing the resol type and the initial temperature (or acid catalyst amount), an optimum amount of acid catalyst (or initial temperature), related to the maximum foaming extent, was found. The structure of the resulting foams was examined with scanning electron microscopy.
Advance of Flexible Polyurethane Foam Technology
Authors: Creyf H. , Fishbein J.
Published: August 2023

The polyurethane industry presents a whole range of flexible polyurethane foams which, when selected properly for its application, offer an adequate fire behaviour. Different PU foams exist which resist a whole range of ignition sources, from lighted cigarettes to sources up to 7 kg of wood. In order to appreciate the costs involved, a risk analysis is required, taking into account the composite behaviour and the influences of the environment.
Isocyanurate Crosslinking as a Means of Producing Thermally Stable Polyurethane Elastomers
Authors: Barikani Mehdi , Hepburn Claude
Published: August 2023

Castable polyurethane solid elastomers (PUS) based on the poly-caprolactone ( CAPA 225) and the cycloaliphatic diisocyanate trans 1,4–cyclohexane diisocyanate (CHDI) were synthesised to form two series of PUS: in one series the initially prepared prepolymer was chain extended with 1,4–butane diol (BDO) whilst in the second series a mixed chain extender system was used. The first PU elastomer series synthesised had the following composition CAPA 225/CHDI/BDO and covered the molar ratio range 1/2/1 to 1/3/1; the second series CAPA 225/CHDI/BDO + CHDM covered the molar range 1/3/2 to 1/4·5/2. In each series a controlled excess of diisocyanate was allowed to remain in the initially formed PUS: within a particular series each polymer differed from its immediate analogue by 5% excess NCO and the series covered the range 0–50% of excess NCO in a series of 5% steps.

It was discovered that elastomers containing a molar excess of iso-cyanate which had been cast and initially cured at 120°C for 16 h were apparently free from reactive NCO groups and did not emit hazardous fumes when subjected to post-curing or rearrangement by heating to 130°C. When, after conditioning for I week, these PUS are post-cured at a higher temperature (16 h at 130°C) then a second crosslinking system is formed in situ in the PU which considerably enhances its thermal deformation and heat resistance properties. The conventional PU system possessing typically 0–0·2% of free NCO has a maximum service temperature of approximately 120°C; this is raised to 210–240°C by the use of this excess isocyanate technique.

It is considered that the second in situ crosslinking system consists of isocyanurate type crosslinks. Tensile properties at elevated temperatures and dynamic mechanical thermal analysis (DMTA) were used to measure thermal stability and strength retention.

An important feature of these CHDI based PUS is the remarkable independence of storage modulus to temperature changes. For example, over the temperature range 23–180°C for the BDO series and 23–200°C for the BDO + CHDM series no change is observed. Storage modulus E is defined as dynamic storage modulus with units Nm-2 measured at 10% tensile strain.