bluuebunny/crossref_metadata_2025 huggingface dataset:
Inhibitory activity of Indian spice plant Cinnamomum zeylanicum extracts against Alternaria solani and Curvularia lunata, the pathogenic dematiaceous moulds
Authors: Mishra Ajay K , Mishra Amita , Kehri HK , Sharma Bechan , Pandey Abhay K
Published: March 2009

Background

Dematiaceous moulds are pathogenic microorganisms and act as etiological agents of mycoses with different degrees of severity in humans and animals. These moulds also cause loss of food crops and storage food products. The information regarding antimicrobial efficacy of the plant preparations on these moulds is scanty. The present study reveals phytochemical characterization and the effect of bark and leaf extracts of Indian spice plant, Cinnamomum zeylanicum (Cz), against the growth of two species of dematiaceous moulds, Alternaria solani and Curvularia lunata.

Methods

Cz bark and leaf samples were sequentially extracted in different solvents using Soxhlet apparatus. Phytochemical analyses of extracts were done as per standard protocols. The antifungal bioassay of extracts was done by hanging drop technique. The inhibition of fungal spore germination was monitored under influence of three different concentrations of extracts.

Results

The lowest test concentration (50 μg/ml) of extracts of Cz bark prepared into acetone and that of Cz leaf into petroleum ether and ethanol exhibited complete inhibition (100%) of spore germination in both the moulds. At 100 μg/ml concentration all the extracts showed about 50 to 100% inhibition. However, the treatment of the spores of the two fungal species with highest concentration (500 μg/ml) of bark and leaf extracts in all the solvents showed 100% fungicidal activity as it completely arrested the germination of spores. Relatively lower activity of aqueous extracts at 50 and 100 μg/ml concentrations suggests that the antifungal ingredients present in Cz bark and leaf are more soluble in organic solvents than water.

Conclusion

The results demonstrated that the Cz bark and leaves contain certain fungicidal constituents exhibiting potential antimould activity against A. solani and C. lunata.
Intravenous flurbiprofen axetil can increase analgesic effect in refractory cancer pain
Authors: Wu Hongyang , Chen Zhendong , Sun Guoping , Gu Kangsheng , Pan Yueyin , Hao Jiqing , Du Yingying , Ning Jie
Published: March 2009

Background

The aim of this study was to investigate the analgesic effects of intravenous flurbiprofen axetil for the refractory pain in cancer patients.

Methods

2109 patients were screened from the department of medical oncology, the first affiliated hospital of Anhui medical university in China between October of 2007 and October of 2008. Thirty-seven cases of cancer patients who had bad effect from anaesthetic drugs were received administration of intravenous flurbiprofen axetil with dose of 50 mg/5 ml/day. The pain score was evaluated for pre- and post- treatment by Pain Faces Scale criteria, and the side effects were also observed.

Results

Intravenous flurbiprofen axetil increased the analgesic effects. The total effective rate was 92%. The side effects, such as abdominal pain, alimentary tract bleeding which were found in using NSAIDs or constipation, nausea, vomit, sleepiness which were found in using opioid drugs did not be found.

Conclusion

Intravenous flurbiprofen axetil could provide better analgesia effects and few side effects to patients with refractory cancer pain. It could also increase analgesia effects when combining with anesthetic drugs in treatment of moderate or severe pain, especially breakthrough pain, and suit to patients who can not take oral drugs for the reason of constipation and psychosomatic symptoms.
Glycolytic control of adjuvant-induced macrophage survival: role of PI3K, MEK1/2, and Bcl-2
Authors: Chang Margaret , Hamilton John A , Scholz Glen M , Elsegood Caryn L
Published: March 2009

Uptake by macrophages forms an important part of the mode of action of particulate adjuvants such as oil-in-water emulsions and alum. We have found previously that such adjuvants promote macrophage survival and suggested that this response may contribute to their efficacy. To explore this adjuvant activity further, we have investigated whether oil-in-water emulsion stimulates glucose uptake in macrophages and whether such uptake is relevant to the promotion of survival. We found that oil-in-water emulsion stimulated glucose uptake in a biphasic manner. The first acute phase was independent of mRNA and protein synthesis but appeared to require PI3K activity. In contrast, the second chronic phase was dependent on mRNA and protein synthesis. Importantly, the second phase of glucose uptake required MEK1/2 as well as PI3K activity, indicating that the MEK1/2 pathway can also contribute to cellular glucose uptake. The increased glucose transporter 1 expression during the second phase and long-term survival also appeared to be dependent on PI3K and MEK1/2 signaling pathways. Metabolism of the glucose was required for the emulsion-stimulated survival as well as the increase of prosurvival Bcl-2 transcript levels and maintenance of Bcl-2 protein expression. As transgenic overexpression of Bcl-2 enhances the survival of macrophages in the absence of growth factor, the glycolytic control of Bcl-2 levels may play a central role in emulsion-stimulated macrophage survival. Enhanced glucose uptake by macrophages may therefore be critical to the action of particulate adjuvants.
“What Does Death Represent to the Individual?” Psychoanalysis and Wartime
Authors: Stonebridge Lyndsey
Published: March 2009

Why is it that we respond to the deaths of others in wartime with an apparent indifference? What is it about our desire that so readily accommodates the representation of the death of others? This article addresses these questions through a reading of Freud's 1915 essay on war and Klein's 1940s writing on mourning and the fear of death. Between them, Freud and Klein produce a compelling narrative about what it means to live in fear not only of death, which is where Freud begins his critique of the normalizing pathologies of war at the beginning of the century, but also of one's own violence, which is where Klein takes that critique fifteen years later. What starts as a question for Freud about how it is that war legitimizes a murderous representation of the other becomes, in Klein, a question about the morality of mourning. In wartime, this morality becomes political, as Klein's pressing therapeutic question—how might one mourn without violence?—is yoked to a more immediately historical imperative: how is it possible to live in terror without reproducing an annihilating denial of the other?
The Red Line: Pressure and Persuasion in Greek Diplomatic Strategies on Cyprus, 1945 to 2004
Authors: Hatzivassilou Evanthis
Published: March 2009

The negotiating position of an international player is strengthened when it can persuade third parties that it has reached the limits of its concessions. However, from 1945 to 2004 the Greek side (both Athens and Nicosia) managed convincingly to convey this message to the international community only twice: in 1958, prior to the conclusion of the agreements for Cypriot independence, and in 2004, when the Annan Plan was rejected by the Greek-Cypriot community. This failure of the Greek side should be attributed to a combination of maximalism, lack of accurate assessments of the interests and objectives of other actors, and lack of consistency in Greek discourse.
The Soft Power of the Ecumenical Patriarchate
Authors: Yannas Prodromos
Published: March 2009

The Ecumenical Patriarchate is considered first among equals of all the Orthodox churches and presides over 200 million Christians. The ecumenical mission of the patriarchate is seriously contested by the official stance of the Turkish government and by ultranationalists who fear that the patriarchate might gain extraterritorial privileges and become a Vatican. At present, the Ecumenical Patriarchate is an institution with a global reach, but one that lacks a legal personality. The essay presents the two contrasting perspectives regarding the ecumenical status of the patriarchate and documents how the sources of the patriarchate's soft power marshal support in favor of its ecumenical mission.
Interface Modification of Dye-sensitized Solar Cells with Pivalic Acid to Enhance the Open-circuit Voltage
Authors: Li Xin , Lin Hong , Zakeeruddin Shaik M , Grätzel Michael , Li Jianbao
Published: March 2009

Pivalic acid (PVA) was used as a new coadsorbent to dye-sensitized solar cells (DSCs) to modify the interface between the TiO2 films and electrolyte. The addition of PVA improved the light-to-electricity conversion efficiency of devices by 8% by enhancing the open-circuit voltage.
Optimal Policies and Approximations for a Bayesian Linear Regression Inventory Model
Authors: Azoury Katy S. , Miyaoka Julia
Published: March 2009

In this paper, we consider a periodic review inventory problem where demand in each period is modeled by linear regression. We use a Bayesian formulation to update the regression parameters as new information becomes available. We find that a state-dependent base-stock policy is optimal and we give structural results. One interesting finding is that our structural results are not analogous to classical results in Bayesian inventory research. This departure from classical results is due to the role that the independent variables play in the Bayesian regression formulation. Because of the computational complexity of the optimal policy, we propose a combination of two heuristics that simplifies the Bayesian inventory problem. Through analytical and numerical evaluation, we find that the heuristics provide near-optimal results.
A Generalized Approach to Portfolio Optimization: Improving Performance by Constraining Portfolio Norms
Authors: DeMiguel Victor , Garlappi Lorenzo , Nogales Francisco J. , Uppal Raman
Published: March 2009

We provide a general framework for finding portfolios that perform well out-of-sample in the presence of estimation error. This framework relies on solving the traditional minimum-variance problem but subject to the additional constraint that the norm of the portfolio-weight vector be smaller than a given threshold. We show that our framework nests as special cases the shrinkage approaches of Jagannathan and Ma (Jagannathan, R., T. Ma. 2003. Risk reduction in large portfolios: Why imposing the wrong constraints helps. J. Finance 58 1651–1684) and Ledoit and Wolf (Ledoit, O., M. Wolf. 2003. Improved estimation of the covariance matrix of stock returns with an application to portfolio selection. J. Empirical Finance 10 603–621, and Ledoit, O., M. Wolf. 2004. A well-conditioned estimator for large-dimensional covariance matrices. J. Multivariate Anal. 88 365–411) and the 1/N portfolio studied in DeMiguel et al. (DeMiguel, V., L. Garlappi, R. Uppal. 2009. Optimal versus naive diversification: How inefficient is the 1/N portfolio strategy? Rev. Financial Stud. 22 1915–1953). We also use our framework to propose several new portfolio strategies. For the proposed portfolios, we provide a moment-shrinkage interpretation and a Bayesian interpretation where the investor has a prior belief on portfolio weights rather than on moments of asset returns. Finally, we compare empirically the out-of-sample performance of the new portfolios we propose to 10 strategies in the literature across five data sets. We find that the norm-constrained portfolios often have a higher Sharpe ratio than the portfolio strategies in Jagannathan and Ma (2003), Ledoit and Wolf (2003, 2004), the 1/N portfolio, and other strategies in the literature, such as factor portfolios.
On the Value of Commitment and Availability Guarantees When Selling to Strategic Consumers
Authors: Su Xuanming , Zhang Fuqiang
Published: March 2009

This paper studies the role of product availability in attracting consumer demand. We start with a newsvendor model, but additionally assume that stockouts are costly to consumers. The seller sets an observable price and an unobservable stocking quantity. Consumers anticipate the likelihood of stockouts and determine whether to visit the seller. We characterize the rational expectations equilibrium in this game. We propose two strategies that the seller can use to improve profits: (i) commitment (i.e., the seller, ex ante, commits to a particular quantity) and (ii) availability guarantees (i.e., the seller promises to compensate consumers, ex post, if the product is out of stock). Interestingly, the seller has an incentive to overcompensate consumers during stockouts, relative to the first-best benchmark under which social welfare is maximized. We find that first-best outcomes do not arise in equilibrium, but can be supported when the seller uses a combination of commitment and availability guarantees. Finally, we examine the robustness of these conclusions by extending our analysis to incorporate dynamic learning, multiple products, and consumer heterogeneity.
Certifications and Reputation: Determining the Standard of Desirability Amidst Uncertainty
Authors: Graffin Scott D. , Ward Andrew J.
Published: March 2009

We develop a theory that examines how a particular type of third-party quality signal, certifications, influences an actor's long-term reputation by addressing two different types of uncertainty. The first type deals with the degree to which the capabilities of an actor can be inferred over time based on known performance dimensions. We label this technical uncertainty. The second type deals with assessing whether the perceived capabilities of the actor meet the standard of desirability, which we call performance standard uncertainty. We propose and test that certifications will positively influence the long-term reputation of actors in situations that involve minimal technical uncertainty, and that, across levels of technical performance, certifications will have an inverted U-shaped relationship with assessments of actors such that certifications will have the greatest impact on assessments of actors who are close to the uncertain standard of desirability. We test our hypotheses in the context of the voting for Major League Baseball's Hall of Fame, an environment where comprehensive technical performance measures leave little technical uncertainty. Our results support our hypotheses and suggest that certifications can influence an actor's reputation by reducing performance standard uncertainty rather than just technical uncertainty, as previously presumed.
Capabilities Unveiled: The Role of Ordinary Activities in the Evolution of Product Development Processes
Authors: Salvato Carlo
Published: March 2009

In contrast to the prevailing interpretation of capabilities as collectives, this inductive study of product development in a leading design firm highlights the centrality of the myriad ordinary activities that may shape the evolution of capabilities. A detailed comparison of 90 diverse product development processes over a 15-year period shows, first, that mindful microactivities carried out by individuals in and around the organization and at all levels of the organizational hierarchy are central in shaping the content of the product development capability and its dynamic adaptation. Understanding organizational renewal and competitive advantage may hence require a partial shift in focus from capabilities as aggregate entities, to the practical realities of core organizational processes. Second, this more fine-grained perspective leads to a set of insights on how organizational renewal may be partially shaped by timely managerial interventions aimed at encoding successful experiments into higher-level organizational capabilities. Third, higher-level capabilities resulting from the conversion of heterogeneous experiences display higher process homogeneity and a permanent increase in performance, because of stabilization of managerial attention. My findings contribute to unveiling the concept of capabilities, extending prior research on dynamic capabilities and organizational renewal and providing a lens for research on the microfoundations of capability evolution and organizational advantage.
Technology, Identity, and Inertia Through the Lens of “The Digital Photography Company”
Authors: Tripsas Mary
Published: March 2009

Organizations often experience difficulty when pursuing new technology. Large bodies of research have examined the behavioral, social, and cognitive forces that underlie this phenomenon; however, the role of an organization's identity remains relatively unexplored. Identity comprises insider and outsider perceptions of what is core about an organization. An identity has associated with it a set of norms that represent shared beliefs about legitimate behavior for an organization with that identity. In this paper, technologies that deviate from the expectations associated with an organization's identity are labeled identity-challenging technologies. Based on a comprehensive field-based case study of the entire life history of a company, identity-challenging technologies are found to be difficult to capitalize on for two reasons. First, identity serves as a filter, such that organizational members notice and interpret external stimuli in a manner consistent with the identity. As a result, identity-challenging technological opportunities may be missed. Second, because identity becomes intertwined in the routines, procedures, and beliefs of both organizational and external constituents, explicit efforts to shift identity in order to accommodate identity-challenging technology are difficult. Given the disruptive nature of identity shifts, understanding whether technology is identity challenging is a critical consideration for managers pursuing new technology.
Innovation and Strategic Renewal in Mature Markets: A Study of the Tennis Racket Industry
Authors: Kim Hann Earl , Pennings Johannes M.
Published: March 2009

This paper presents a study of successive new product introductions in the mature tennis racket industry. The inquiry examines novel design's important role in strategic renewal, under the assumption that innovation includes not only the development, production, and launch of new products, but also communication between firms and market. We explore this industry's transformation through the strategic actions of innovative firms and subsequent competitive contagion. A tennis racket innovation triggers competitors' imitative reactions and sways the market toward a new de facto standard when the new product launch includes marketing such as product endorsement by high-profile professional players and advertising. Our results indicate that innovators should actively manage various industry participants as an integral part of their strategic renewal efforts, especially when facing rivalry with “me-too” peers. We suggest the interface between firms and consumers as a next focus for research on strategic renewal.
Integrating Acquired Capabilities: When Structural Integration Is (Un)necessary
Authors: Puranam Phanish , Singh Harbir , Chaudhuri Saikat
Published: March 2009

Acquirers who buy small technology-based firms for their technological capabilities often discover that postmerger integration can destroy the very innovative capabilities that made the acquired organization attractive in the first place. Viewing structural integration as a mechanism to achieve coordination between acquirer and target organizations helps explain why structural integration may be necessary in technology acquisitions despite the costs of disruption this imposes, as well as the conditions under which it becomes less (or un-) necessary. We show that interdependence motivates structural integration but that preexisting common ground offers acquirers an alternate path to achieving coordination, which may be less disruptive than structural integration.
Strategic Renewal of Organizations
Authors: Agarwal Rajshree , Helfat Constance E.
Published: March 2009

Strategic renewal, although critical for the sustained success of organizations, has received relatively little attention as distinct from the more general phenomenon of strategic change. Like all strategic issues, strategic renewal presents both opportunities and challenges for organizations. In this article, we first define the term “strategic renewal” and elaborate on important characteristics of this phenomenon. We also bring to bear evidence that suggests that strategic renewal has a critical impact not only on individual firms and industries but also on entire economies. We then provide an in-depth example of a company that has successfully renewed itself more than once, namely, IBM. Finally, we examine several different avenues for strategic renewal, involving both content and process, and identify common themes among them.
Reduced Activation Materials for Fusion Reactors
Authors: Klueh RL , Gelles DS , Okada M , Packan NH
Published: March 2009

Description

Material for future reactors is the focus of this new publication from ASTM. Eighteen papers anticipate safety and waste disposal problems from induced radioactivity in the reactor materials. Papers presented in three sections:

• Austenitic Stainless Steels

• Ferritic Steels

• Vanadium Alloys
Bioprocessing Safety: Worker and Community Safety and Health Considerations
Authors: Hyer WC
Published: March 2009

Description

Presents basic concepts in the safe and responsible integration of the bioprocess facility into the local community for decision makers who have no formal training in biosafety issues.
Fatigue and Fracture Testing of Weldments
Authors: Potter JM , McHenry HI
Published: March 2009

Description

Presents 15 authoritative papers on the structural integrity of weldments not available from other sources. This comprehensive text covers low and high cycle fatigue, fatigue crack growth, corrosion fatigue, fracture toughness testing, and wide-plate testing.
Petrography Applied to Concrete and Concrete Aggregates
Authors: Erlin B , Stark D
Published: March 2009

Description

14 peer-viewed papers cover approaches, examination, and specimen preparation of concrete and aggregates for petrographic studies; petrographic examination of aggregate problems; and petrography applied to solving varieties of concrete problems. Provides helpful information both to those who conduct petrographic investigations and to those who use petrographic information to fulfill their analysis needs. For petrographers, geologists, concrete technologists, engineers, and research and development organization involved with Portland cement, concrete, aggregates, and admixtures for concrete.
Acoustic Emission: Current Practice and Future Directions
Authors: Sachse W , Yamaguchi K , Roget J
Published: March 2009

Description

Topics addressed include: sensors and AE systems; fundamental aspects of AE acousto-ultrasonics; new AE signal processing techniques; structural monitoring applications; material deformation studies; novel applications of AE measurement; geotechnical applications; and the use of AE to monitor failure processes in composite materials.
Pesticide Formulations and Application Systems: 10th Volume
Authors: Bode LE , Hazen JL , Chasin DG
Published: March 2009

Description

Provides the most up-to-date information on pesticide formulations and techniques for applying pesticides. 21 papers are organized into 3 categories:

• Perspectives on Pesticide Risks

• Formulation Technology and Characteristics of Uptake

• Application Systems
Slips, Stumbles, and Falls: Pedestrian Footwear and Surfaces
Authors: Gray BE
Published: March 2009

Description

The purpose of ASTM sponsored F13 Committee Symposium titled "Slips, Stumbles, and Falls: Pedestrian Footwear and Surfaces" was the presentation of new ideas relating to pedestrian walking related accidents.
Tribological Modeling for Mechanical Designers
Authors: Ludema K , Bayer RG
Published: March 2009

Description

13 papers written by research tribologists are presented in chapters on:

• What Mechanical Designers Need in Tribological Modeling

• What is Available in Tribological Models

• Data Base and Simulation issues for Tribiological Modeling

• Simulation of Model Making and Use
Modern Instrumental Methods of Elemental Analysis of Petroleum Products and Lubricants
Authors: Nadkarni RA
Published: March 2009

Description

Informs analysts and marketers of state-of-the-art methodology for the elemental analysis of petroleum products and lubricants. The first two papers are comprehensive reviews describing the occurrence and significance of trace metals in petroleum-related materials.
Pesticide Formulations and Application Systems: Eleventh Volume
Authors: Bode LE , Chasin DG
Published: March 2009

Description

Brings together ideas and data from chemists and engineers who are working to improve the efficiency of pesticide use. 22 papers cover:

• Safety and Environmental Impacts

• Characteristics of Formulations and Adjuvants

• Application Techniques and Pest Control
Insulation Materials: Testing and Applications, 2nd Volume
Authors: Graves RS , Wysocki DC
Published: March 2009

Description

Brings together the latest research data on thermal insulation materials. 38 papers cover:

• Reflective/Radiant Barriers/Radiation Control Coating

• Economics and Energy impact

• Long-Term Thermal Performance of Foams

• Assessments and Properties of Foams

• Convection in Fibrous Insulation

• Tests and Models

• Performance Factors

• Innovative Insulations

• Test Methods and Comparisons
Pavement Management Implementation
Authors: Holt FB , Gramling WL
Published: March 2009

Description

STP 1121 will help you assess, design, and implement pavement management systems. Includes 31 peer-reviewed papers in two sections:

• Overview (history of pavement management, requirements of pavement management systems, problems of implementing a system, and how to evaluate pavement management systems)

• Experience (20 papers detailing the experience of users).
Damage Detection in Composite Materials
Authors: Masters JE
Published: March 2009

Description

Designing, building, certifying, and maintaining a composite structure requires the coordinated efforts of the material scientist, the stress analyst, and the NDE specialist. The interaction of these disciplines is the theme of this new volume from ASTM.

16 peer-reviewed papers are presented in two categories: Advanced Imaging and Measurement Techniques and Manufacturing and Service-Induced Damage.

For composite material users; stress analysts, design engineers, structural engineers, inspection (NDE) engineers. Also for researchers at universities and government laboratories.
Acoustic Emission Testing of Aerial Devices and Associated Equipment Used in the Utility Industries
Authors: Bingham AH , Ek CW , Tanner JR
Published: March 2009

Description

STP 1139 presents case histories and the benefits realized by utilities that have used acoustic emission testing of aerial equipment. These 15 papers, representing 15 years of experience, can greatly enhance your testing programs.
Composite Materials: Fatigue and Fracture, Fourth Volume
Authors: Stinchcomb W , Ashbaugh N
Published: March 2009

Description

Addresses current issues related to fatigue and fracture of composites and practical insights on new developments in damage and failure analysis and test methods. Provides new directions for emerging technology areas, such as micro mechanics and interfacial analysis, which are applicable to fatigue and fracture of composites. The materials addressed are thermo-composites, metal matrix composites, and ceramic matrix composites, as well as a specialty laminate.
Vehicle, Tire, Pavement Interface
Authors: Henry JJ , Wambold JC
Published: March 2009

Description

Vehicle and tire meet the pavement at the vehicle-tire-pavement interface. Representatives of the vehicle, tire, and pavement fields take a look at mutual problems in this new publication from ASTM.
Thermomechanical Fatigue Behavior of Materials
Authors: Sehitoglu H
Published: March 2009

Description

Topics covered:

• the dramatic contribution of oxidation on fatigue crack growth in thermomechanical fatigue by comparing preoxidized and virgin samples

• dynamic strain aging and dynamic recovery effects in austenitic stainless steels under thermomechanical fatigue

• thermomechanic fatigue of IN-738 and proposed life model incorporating time, temperature, and stain effects

• analysis of local stresses and strains for same class of materials

• characterization of crack growth through temperature and stress gradients.
Fracture Mechanics: Twenty-Third Symposium
Authors: Chona R
Published: March 2009

Description

45 peer-reviewed papers in 7 sections:

• Elastic-Plastic Fracture Mechanics--Analyses and Constraint Issues

• Elastic-Plastic Fracture Mechanics--Applications

• Linear-Elastic Fracture mechanics--Analyses

• Linear-Elastic Fracture Mechanics--Applications

• Fatigue and Nondestructive Evaluation

• Composites and Nonmetals

• Probabilistic and Dynamic Issues
Modeling of Indoor Air Quality and Exposure
Authors: Nagda NL
Published: March 2009

Description

Provides you with both the underlying theory and examples of practical applications of models. 20 peer-reviewed papers discuss:

• interactions between sources and sinks of indoor air pollution

• problem areas related to model validation and their solutions

• application of models to evaluate ventilation performance and indoor air quality implications of proposed indoor space designs

• design and assessment of natural ventilation strategies and prediction of smoke movement

• use of models to predict formaldehyde and radon concentrations

• development and use of models to predict human exposures to toxic contaminants such as benzene.

In three sections: modeling and measuring sources and sinks; model validation and application; and modeling of exposures.
Fracture Mechanics: Twenty-Fourth Volume
Authors: Landes JD , McCabe DE , Boulet JAM
Published: March 2009

Description

Contains significant insight on the latest international developments in fracture mechanics. Central thermes are constraint issues and nonlinear fracture mechanics. Several papers also deal with the industry's most active topic of study, the two-parameter fracture mechanics approach to constraint and its impact on transition fracture toughness.

9 sections cover:

• Progress in Fracture Mechanics Research

• Constraint Issues

• Ductile to Brittle Transition

• Elastic-Plastic Fracture

• High Temperature Effects

• K Analysis

• Applications

• Fatigue

• Nonmetallic Materials
Computerized Chemical Data Standards: Databases, Data Interchange, and Information Systems
Authors: Lysakowski R , Gragg CE
Published: March 2009

Description

To remain competitive, industries most computerize as much of their chemical data as possible. Manufacturers dependent on chemical data need access to rapid, on-line information, and yet few formal standards exist for database storage, the exchange of chemical structure data, analytical chemistry data, or for presentation of chemical information to end users. STP 1214 presents 13 peer-reviewed papers written by leaders in the field of chemical data computerization. The papers cover:

• molecular structure information

• analytical (testing) laboratory information

• and presentation and publication of chemical data.

This handy reference provides you with examples on how to standardize data interchange; explanations on techniques such as abstract data modeling, object-oriented analysis, design, and implementation; and requirements for current and future standards in chemistry, including systems modeling and abstract data modeling.
Analysis of Soils Contaminated with Petroleum Constituents
Authors: Hoddinott K , O'Shay T
Published: March 2009

Description

Presents the latest research on analytical procedures for soil contaminated with petroleum hydrocarbons, and the behavior of hydrocarbons, and the behavior of hydrocarbon contaminated soils.

9 peer-reviewed papers cover:

• Differences and difficulties in recovering oil from a soil sample

• Attributes of the fuel isolation, identification, and quantitation method

• Applicability of Supercritical Fluid Extraction (SFE) to the preparation of oil contaminated soil samples

• A tiered analytical protocol for characterizing heavy oil residues in soil

• Three methods for measuring petroleum hydrocarbons in soil

• Petroleum hydrocarbon analytical techniques and their limitations

• Effects of crude oil contamination on compaction, stress deformation, compressibility, shear strength, and permeability characteristics of sand.

• Experimental and modeling approaches to understand the behaviors of oil in soils.
Rationale for the Design and Use of Pure Titanium Internal Fixation Plates
Authors: Baumgart FW , Perren SM
Published: March 2009

Commercially pure titanium is standardized by ISO 5832-2 and has better fatigue strength than stainless steel. Its other mechanical properties are comparable to the properties of stainless steel.

Bone plates need contouring in most cases of application. A retrospective evaluation of more than 500 clinical cases showed that the initiated strain by contouring is on average about 1.6% below the elongation at fracture for cp titanium. Therefore, contouring of titanium plates having equivalent design to stainless steel plates is not critical.

The most important properties of pure titanium are its excellent biocompatibility and its corrosion resistance. The metal is protected by a very thin and tough layer of titanium oxide. Anodizing gives the titanium oxide layer a certain color.

No allergic reactions to cp titanium are known so far. The debris of titanium caused by relative movement of implant parts which are in contact consists of titanium oxide and has a dark color. This may be sometimes undesirable for cosmetic reasons but the particles do not contain any toxic element.

Pure Titanium is an appropriate material for bone plates and screws used for internal fixation.
The Concept of Biological Internal Fixation Using Limited Contact Plates
Authors: Baumgart FW , Perren SM
Published: March 2009

The internal fixation of bone fractures aims at early, complete and lasting recovery of limb function. for many years, emphasis was placed on precise reduction and interfragmentary compression as a means of keeping the fragment surfaces from moving. In cases of multifragmentary fractures, this procedure involves extensive surgical intervention and causes additional damage to the circulation of bone. The idea of biological fixation based on the work of Ganz and Mast aims to achieve a sufficiently stable fixation with minimal encroachment on the intact tissue.

A common phenomenon observed in relation to internal fixation using bone plates is that of temporary porosis beneath the plate. Bone remodelling occurred and infection was liable to cause the formation of a sequestrum. This porosis was initially explained in mechanical terms as the result of the stress protection function of the plate. Later the work of Gunst, Gautier, Rahn, and Perren et al. demonstrated that the disturbance of blood flow due to compression of the periosteum was the important factor. This has lead to the development of the limited contact dynamic compression plate (LC-DCP). The LC-DCP has proved its worth as an implant which complies with the concept of biological fixation and which has improved the quality of treatment in general.
Scale Effects on the Transverse Tensile Strength of Graphite/Epoxy Composites
Authors: O'Brien TK , Salpekar SA
Published: March 2009

The influence of material volume on the transverse tensile strength of AS4/3501-6 graphite/epoxy composites was investigated. Tension tests of 90° laminates with three different widths and five different thicknesses were conducted. A finite element analysis was performed to determine the influence of the grip on the stress distribution in the coupons and explain the tendency for the distribution of failure locations to be skewed toward the grip. Specimens were instrumented with strain gages and extensometers to ensure good alignment and to measure failure strains. Data indicated that matrix dominated strength properties varied with the volume of material that was stressed, with the strength decreasing as volume increased. Transverse strength data were used in a volumetric scaling law based on Weibull statistics to predict the strength of 90° laminates loaded in three-point bending. Comparisons were also made between transverse strength measurements and out-of-plane interlaminar tensile strength measurements from curved beam bending tests. The significance of observed scale effects on the use of tests for material screening, quality assurance, and design allowables is discussed.
Evaluation of Compression Specimens and Fixtures for Testing Unidirectional Composite Laminates
Authors: Daniels JA , Sandhu RS
Published: March 2009

This two-part study consisting of analysis and experimentation was used to evaluate six fixtures and the corresponding specimens. The stress state in each specimen was determined using the finite element technique. In the experimental portion of this study, specimens corresponding to each of the six fixtures were cut from [0°]16 panels fabricated from a graphite/epoxy (AS4/3501-6) material system and tested. The results of this analytical/experimental study indicate that the test techniques that incorporate side support plates to prevent buckling of end-loaded specimens provide an inaccurate measure of compressive strength and their use should be discontinued. Among the shear loaded specimens, the performance of the IITRI fixture was determined to be inadequate due to a nonuniform state of stress in the test section and it was improved significantly by the use of Sendeckyj-Rolfes specimen. The Celanese fixture yielded good results except that the specimen was so narrow that it was difficult to instrument and test. It was determined that in terms of average compressive failure strength and uniformity of stress in the test section, the Rolfes fixture using the Sendeckyj-Rolfes specimen outperformed the other five fixtures/specimens tested.
The Effect of Mixed-Mode Loading on Delamination Fracture Toughness
Authors: Sriram P , Khourchid Y , Hooper SJ
Published: March 2009

Interlaminar fracture (delamination) is the dominant failure mechanism in most advanced composite materials. The resistance of a material system to delamination failure is generally quantified in terms of the interlaminar fracture toughness, Gc. The recently developed Mixed-Mode Bending (MMB) test is unique in that it facilitates measurement of the fracture toughness Gc under any combination of mixed-mode loading from pure Mode I to pure Mode II. This makes it a very attractive technique for developing interlaminar fracture failure criteria. This paper reports on an application of the MMB test to fatigue loading for the generation of Gc versus-curves and identification of the threshold value, Gth. Fatigue results from unidirectional IM7/5260 graphite/bismaleimide and IM7/8320 graphite/thermoplastic specimens are presented for a GI/GII ratio of 0.25. Static test results are also presented for both materials with the mode mix varying from pure Mode I to pure Mode II. The static results indicate different mixed mode failure laws for the two materials. All tests were conducted using displacement controlled loading under room temperature, dry conditions.
A Summary of Ono's Method for Cement Quality Control with Emphasis on Belite Color
Authors: Campbell DH
Published: March 2009

The use of Ono's Method for cement quality control is standard in plants of the Onoda Cement Company and other producers in Asia. Widespread use of the technique is found in cement plants of North and Central America. Alite birefringence, alite size, belite size, and belite color are reported to correlate with kiln conditions and hydraulic activity. The present paper is a preliminary evaluation of belite color, particularly as it relates to 28-day mortar-cube strength. Thirty samples of portland cement clinker or cement have been examined microscopically to determine the color of belite after extraction of the matrix phases (aluminate and ferrite) with a potassium hydroxide-sugar solution. A positively sloping regression line was found with a plot of percentages of clear plus pale yellow belite crystals (single and nested) and 28-day mortar cube strength; negatively sloping lines were found with plots of percentages of single and nested yellow and amber crystals, plus crystals with abundant dotlike impurities. Both single and nested crystals exhibit these relationships with 28-day strength.
The Microstructural Approach to Solving Clinker-Related Problems
Authors: Sarkar SL , Samet B
Published: March 2009

The paper discusses in detail the principles underlying today's common microstructural investigative techniques and their capabilities in diagnosing problems associated with clinker manufacture and their properties.

Several characterization techniques are available to the cement scientist/technologist. These can be divided into two broad categories, namely direct observation techniques: optical microscopy and scanning electron microscopy (SEM). An additional tool used in conjunction with SEM is the energy dispersive X-ray analyzer (EDXA) unit which enables chemical analysis to be performed simultaneously. Indirect interpretative technique mainly comprises X-ray diffraction (XRD).

While all these techniques offer useful information and some definite answers concerning raw materials, thermal history of clinkerization, and resulting clinker properties, sample preparation method is of prime importance in order to derive accurate data. Each technique requires a specific sample preparation process. These are described at some length.

A number of case histories of microstructural and microanalytical characterization of clinkers are also presented in order to highlight their importance in solving clinker-related problems.
Petrographic Examination of Reinforced Concrete from Cathodically Protected Structures
Authors: Lankard DR , Scaglione NJ , Bennett JE
Published: March 2009

Core samples were obtained from eleven 18-year to 32-year old reinforced concrete bridge and parking structures that have been under cathodic protection for 2 to 10 years. Characterization studies were conducted on the cores to assess the effects of the sustained cathodic protection current on the anode, the anode/concrete component, and the cathode/concrete component of the cathodic protection system. Characterization techniques included (1) conventional optical petrographie techniques, (2) SEM/EDS techniques, and (3) chloride ion content measurements. The 11 structures represent 8 different CP systems.

Data are also presented on cores taken from 3 ft. x 4 ft. x 6 in. (0.94 m x 1.22 m x 152 mm) reinforced concrete slabs powered for 30 months at 10 mA/ft2, 20 mA/ft2, and 40 mA/ft2 (111 mA/m2, 222 mA/m2, and 444 mA/m2) under laboratory conditions using four different CP anodes.

The investigation has provided new insights into the factors controlling the performance and longevity of the various cathodic protection systems.
A Critical Review of Analytical Approaches for Petroleum Contaminated Soil
Authors: Fan C-Y , Krishnamurthy S , Chen CT
Published: March 2009

The clean up of soils contaminated with petroleum products is associated with several challenges, especially of analytical methodologies and data interpretation.

Petroleum products comprise a vast continuum of hydrocarbons from short chain aliphatic and simple aromatic hydrocarbons in gasoline to kerosene, diesel, and heavy oils and to lubricating oils or vaseline, each gradation with increasing carbon chains and complexity. Gasoline alone may contain over twelve hundred compounds. Properties of these vary and this will be of analytical concern. Treatment technology and site remediation progress will lean heavily on analytical techniques that are accurate, reproducible and of real time value.

This paper examines the various analytical techniques available along with their special features. Some new methods currently under development are also discussed. These include: (1) High Resolution Chromatograph Method which can reveal the detail composition of the contaminants; (2) Supercritical Fluid Extraction which can save time for the analysis; and (3) Fingerprinting which can be used to determine the responsible party for the spill. In addition, the interference due to weathering is also examined.
Physical Properties and Chemical Resistance of Selected Resins for Cured-in-Place Pipe Rehabilitation
Authors: Kleweno DG
Published: March 2009

This report is a summary of the basic chemistry, physical properties, and chemical resistance of six commercially available resins (i.e. vinyl ester, polyester, and epoxy) used for making cured-in-place pipe (CIPP). Flexural and tensile properties are included and chemical resistance from a one year study for each resin-system as a CIPP resin/felt composite in acids, bases, and oxidizing agents currently found or introduced into municipal sanitary sewer systems [1,2,3,4].

Conclusions drawn from this report indicate the three different types of resin had measurably different flexural and tensile properties that ranged the from stiff, brittle behavior to very flexible. Among the test group the two polyesters were relatively stiff, the two epoxy vinyl esters had a balance of high stiffness and strength, one epoxy system was extremely flexible, while the other was similar to the epoxy vinyl esters. The one year chemical resistance also clearly distinguished the performance of the three types of resins. Overall, the two polyester resins performed at an intermediate level, the two epoxy vinyl ester resins demonstrated superior broad range chemical resistance, and the epoxy performance ranged from poor to excellent depending on the type of curing agent used.
Laboratory Test of Buried Pipe in Hoop Compression
Authors: Selig ET , DiFrancesco LC , McGrath TJ
Published: March 2009

A new test has been developed to study the behavior of buried pipe under hoop compression loading. The apparatus consists of a cylindrical steel vessel lined with an inflatable bladder. A length of pipe is installed at the center of the vessel and the annulus between the pipe and the bladder is filled with tamped sand. The test is conducted by incrementally increasing the bladder pressure while monitoring the pipe performance. Radial pressures of 380 kPa (55 psi) and diametral displacement of 37 mm (1.5 in.) have been obtained with corrugated pipes of 610 mm (24 in.) diameter. The technique is believed applicable to any size pipe with any pressure level. The test has demonstrated the significant circumferential shortening that can occur for plastic pipe sections with corrugated cross-sections. This produces beneficial positive arching in service. The test also provides a basis for determining plastic pipe wall design limits in compression.
Rapid Crack Propagation Along Pressurised Plastic Pipe
Authors: Leevers PS , Venizelos GP , Morgan RE
Published: March 2009

Rapid Crack Propagation (RCP) is a rare but dangerous failure mode in gas and water pipelines. Although relatively low RCP resistance may be endemic to plastics, extruded polyethylene pipe varies widely in the critical pressure below which the arrest of RCP is ensured at each temperature. The proposed International Standard ‘S4’ pipe test for RCP, and the prediction of S4 and full-scale test critical pressures from basic material data, are discussed. A more effective quality index may the temperature above which and the wall thickness below which RCP becomes impossible at any sustainable pressure. This brittle-tough transition in polyethylene also appears in dynamic fracture resistance tests as a minimum stable crack velocity. Although the well known Irwin-Corten expression can be used to predict critical pressures for notched, water pressurised pipe, the proximity of this transition velocity to that at which the crack driving force in gas-pressurised pipe is a maximum may preclude a similar approach. Charpy-type tests, on sharp-notched specimens of the base resin at varying temperatures and thicknesses, can be used to locate the transition sufficiently closely to index resins. Predicting the RCP performance of pipe extruded from these resins, however, remains uncertain.