bluuebunny/crossref_metadata_2025 huggingface dataset:
Models of Mutual Solubility Increasing under the Pulse Loading
Authors: Koval'chuk Andriy O. , Gertsriken D.S. , Gusak Andriy , Mazanko V.F.
Published: March 2009

Since 1975 a so-called anomalous mass-transfer in metals and alloys under pulse loading
is being investigated in the Institute of Metal Physics. This phenomenon remains to be a challenge
to theoreticians. Besides, one more phenomenon (observed at the same systems) was discovered –
formation of metastable alloys (solutions, and, sometimes, ordered phases), with solubility limits far
exceeding the equilibrium values and depending on the deformation rate. Since formation of nonequilibrium
phases is also typical for alloys under irradiation, it seemed natural for us to use some
of concepts and models invented in the “materials under irradiation” community. We propose 3
types of models for description of metastable solid solution formation in diffusion couple under
pulse loading: 1) flux balance for both components at the interface with account of non-equilibrium
defects generated during pulse loading; 2) “ballistic jump” concept, which had been invented by
George Martin et al. for materials under irradiation or ball-milling, combined with another Martin’s
kinetic model (1994) of diffusion; 3) modification of such a concept for the case of non-equilibrium
interstitial defects. Non-equilibrium phase diagrams obtained by all 3 models are built and
compared with experimental data which reflect a qualitative correspondence to one another.
Defect Investigation of Plastically Deformed Al 5454 Wrought Alloy Using PADBS and Electrical Measurements
Authors: Abdel-Rahman M. , Kamel N.A. , Lotfy Yahia A. , Badawi Emad A. , Abdel-Rahman M.A.
Published: March 2009

Positron Annihilation Doppler Broadening Spectroscopy (PADPS) is a nondestructive
technique used in materials science. Electrical measurements are one of
the oldest techniques also used in materials science. This paper aims to discuss the
availability of using both PADPS and electrical measurements as diagnostic
techniques to detect defects in a set of plastically deformed 5454 wrought aluminum
alloys. The results of the positron annihilation measurements and the electrical
measurements were analyzed in terms of the two-state trapping model. This model
can be used to investigate both the defect and dislocation densities of the samples
under investigation. Results obtained by both nuclear and electrical techniques have
been reported.
Mercury-Telluride Nanocrystalline Thin Films: A Unique Photoluminescence in the Visible Regime
Authors: Rath S. , Sahu S.N.
Published: March 2009

Stoichiometric mercury-telluride (HgTe) nanocrystals, free from any foreign impurities, have been prepared by an electrochemical technique. Transmission electron microscopy and selected area diffraction studies confirm that the size of HgTe nanocrystals with cubic phase range from 4 – 7 nm and are preferentially oriented. Optical absorption studies indicate that the band gap of HgTe nanocrystals is 2.14 eV. Room temperature photoluminescence measurements show band edge and trap dominated luminescence in the visible regime. Micro-Raman scattering analysis of the HgTe nanocrystals sample reveals the 1LO Raman vibrational mode is at 142.5 cm-1suggesting a shift of 6 cm-1 from it’s bulk value and confirms the crystalline size to be small.
Fabrication of High-Density Nanostructured Alumina by the Combined Processes of Magnetic Pulsed Compaction (MPC) and Spark Plasma Sintering (SPS)
Authors: Lee Jong Keuk , Hong Soon Jik , Lee Min Ku , Rhee Chang Kyu
Published: March 2009

In this study the nanostructured α-Al2O3 ceramics has been fabricated by the combined
application of magnetic pulsed compaction (MPC) and spark plasma sintering (SPS), and their
density and hardness properties were investigated. The α-Al2O3 prepared by the combined
processes showed an increase of 8.4 % in density, approaching a value close to the theoretical
density, a enhancement by 210∼400 Hv in hardness, compared to those for the ones by the MPC or
static compaction method followed by a sintering treatment. Its grain size was almost equivalent to
or slightly higher than the size of the starting Al2O3 powder, suggesting that the grain growth was
remarkably reduced during the MPC and SPS processes.
Application of Statistical Moment Method to Thermodynamic Properties and Phase Transformations of Metals and Alloys
Authors: Masuda-Jindo K. , Van Hung Vu , Turchi P.E.A.
Published: March 2009

The thermodynamic properties and phase transformations of metals and alloys are studied using the statistical moment method, going beyond the quasi-harmonic approximations. Including the power moments of the atomic displacements up to the fourth order, the Helmholtz free energies and the related thermodynamic quantities are derived explicitly in closed analytic forms. The thermodynamic quantities, like thermal lattice expansion coefficients, specific heats, Grüneisen constants, elastic constants calculated by using the SMM are compared with those of other theoretical schemes and the experimental results. The hcp-bcc structural phase transformations observed for IVB elements, Ti, Zr and Hf, are discussed in terms of the anharmonicity of thermal lattice vibrations. The equilibrium phase diagrams are calculated for the refractory Ta-W and Mo-Ta bcc alloys. In addition, the temperature dependence of the elastic moduli C11, C12 and C14 and those of the ideal tensile and shear strengths of the bcc elements Mo, Ta and W are studied: We also discuss the melting transitions of metals and alloys within the framework of the SMM and estimate the melting temperatures through the limiting temperature of the crystalline stability.
Spill Prevention Through Utilization of Preplanning and Inspection Programs
Authors: Fisher Candice , Smith Ken
Published: March 2009

Preplanning activities combined with periodic facility inspections can helpprevent scenarios that result in oil spills, injuries to personnel, or propertydamage. Tools such as preventive maintenance schedules, environmental andsafety audit checklists, response training, and data tracking throughutilization of electronic databases can assist operators towards the ultimategoal of zero incidents. These mechanisms in association with the progressiveprograms espoused by the U.S. Coast Guard, "Prevention Through People", and the Minerals Management Service, "Safety and Environmental Management Program", are key elements in this prevention effort.

Introduction

Planning and preventive maintenance are philosophies that can be applied tomany things in our daily lives. Our vehicles, our homes and even our bodiesrequire preplanning and preventive maintenance measures to help keep themrunning in top condition. The philosophy behind emergency preplanning andpreventive inspection programs for the offshore oil industry is no different. Oil and gas companies who apply preplanning and prevention programs to theirfacilities are proving to be more successful at avoiding pollution and keepingtheir employees safe and healthy. Now more than ever, government agencies likethe Minerals Management Service and the United States Coast Guard areencouraging proactive programs that allow the individual operator considerableleeway in how they utilize their resources to meet regulatory objectives. Somemay ask: Why should lessees or operators spend money to plan for, or preventaccidents or spills that might never happen? If peace of mind is not reasonenough, the following narrative will attempt to explain how these activitiescan help save lives, property, time, and the environment.

Minerals Management Service Pollution Prevention Programs

Minerals Management Service's (MMS) Mission Statement says it strives: "Tomanage mineral resources on the Outer Continental Shelf in an environmentallysound and safe manner." It is a brief statement for a big job that continues togrow in scope as the impetus shifts toward environmental awareness andpersonnel health and safety as they relate to offshore operations. The movetoward operator accountability in the preplanning and prevention arenas hasplaced MMS in an increasingly coach-like role.
Utilization of an Oil Spill Cooperative To Meet Worst Case Discharge Requirements
Authors: Eisterhold James F. , Armstrong R.W.
Published: March 2009

There are over 25 industry-funded major oil spill response organizations(co-ops) in the United States. Each co-op decides the type and quantity ofequipment necessary to not only respond effectively to a spill, but to alsomeet regulatory requirements for worst case discharge scenario planning. Clean Gulf Associates (CGA), a co-op organized by Gulf of Mexico oil and gasproducers was founded in 1972. The initial inventory consisted ofself-contained skimming systems designed for deployment from vessels ofopportunity, a skimming barge converted from a deck cargo barge, shallow waterskimmers and near shore boom. In selecting equipment, the co-op benefited fromexperience gained during major spill events in Main Pass and Bay Marchand. The Participation Area was offshore Louisiana.

CGA contracted with a large service company to purchase, store and maintainthe desired equipment. In the event of a spill, the member utilized CGAequipment and contracted directly with third parties for personnel to operatethe equipment.

The Participation Area has since expanded to include the entire Gulf of Mexico. The spill response inventory now consists of four models of the Fast Response (Skimming) System, a large, purpose-built skimming barge, two designsof shallow water skimmers, three types of containment boom, two ready-to-deployskimming boats, and a large inventory of dispersant. Retainers have beennegotiated with third parties to provide members with aerial dispersantcapability and computer software programs to determine the trajectory of oilspills. In 1997, CGA obtained ownership of the inventory and contracted with anot-for-profit spill response organization to operate, store, and maintain theequipment stockpile.

Since inception, CGA has continued to enhance the response time to spillevents. The Identified Boat program initially consisted of small skimmingpackages installed on members' field boats stationed at offshore facilities. This program has been essentially replaced by a more efficient approachutilizing the two fast, ready-to-deploy skimming boats.

The co-op's working committees continually study ways to improve spillresponse and reduce costs to the membership.
Using Geographic Response Plans and GIS Data Effectively in Incident Management Systems
Authors: Morris David , Barrett Roy
Published: March 2009

Geographic Response Plans (GRP's) are under development by both industry andagencies. The more generic version of these plans is becoming more common inthe Area Contingency Plans. These GRP's often serve as the base for developingmore detailed tactical plans for emergency response and regulatory compliance. These detailed GRP's can effectively identify human and environmental resourcesthreatened by a potential release, as well as displaying what can be done tocontain or mitigate the release. Such plans are being developed by the pipelineindustry, refineries, terminals, and exploration/production operations. Whenthese plans are developed in a Geographic Information System (GIS), they can becombined with newer software tools to become powerful additions to an Incident Management System. The GIS data from these plans can be quickly incorporatedinto an electronic Incident Action Plan and combined with output from newtrajectory models (such as NOAA's GNOME software). The combination createseffective tools to use in response to actual events. Although GIS data andsoftware will not clean up a spill, pre-planning in the proper format can speedup the initial response and greatly improve information flow during anincident.

Introduction

Rapid and effective response is essential to minimize the damage from an oilspill or hazardous substance release. When a spill or release occurs, responders must quickly determine:what resources are threatened;what are the response priorities, or objectives;which plans will best achieve those objectives;what resources are needed to implement those plans; andwhere to get those resources.

This requires that the tedious portion ofdefining detailed response strategies be done in advance of an incident. Thepre-defined strategies must be specific to each geographic area, or sensitivityto be protected (thus the term, Geographic Response Plan). When these areadequately defined in advance, responders can simply choose which strategies toimplement (or modify) based on the conditions present during that incident.

With the proper combination of planning, data, and software, these steps canquickly result in an effective initial response, as well as a good Incident Action Plan for the next response period.
Minerals Management Service Unannounced Drill Program Lessons Learned
Authors: Wright Harold R.
Published: March 2009

In June 1989, the Minerals Management Service (MMS) initiated the Unannounced Drill Program. The regulation is 30 CFR 254.42, Exercises for Your Response Personnel and Equipment (g) The Regional Supervisor periodically willinitiate unannounced drills to test the spill response preparedness of ownersand operators.

The Unannounced Drill Program

July 1989 Through December 1999 75 Drills - 16 - Mobilization, - 1 At Night, 1 Saturday 59 - Tabletop

These drills have been evaluated in comparison with the National Program for Response Preparedness (PREP) guidelines.

Drill Evaluation Categories:Organizational Design ObjectivesOperational Response ObjectivesResponse Support Objectives

This paper will analyze the "Lessons Learned" over the past 10 yearsregarding how the drills evolved and how the response has improved.

Introduction

In the United States, MMS manages the nation's natural gas, oil and othermineral resources on the outer continental shelf, collects, accounts for anddisburses approximately $4 billion to 6 billion yearly in revenue from offshorefederal mineral leases and from onshore mineral leases on Federal and Indianlands.

The MMS Oil Spill Program conducts all unannounced oil spill drills for the Gulf Of Mexico Region. They develop the spill scenario, establish anobservation plan, prepare and disseminate the final technical analysis of thedrill.

When the program began, the industry's spill management teams wereunorganized and ineffective in managing oil spills. Now, with the help of the MMS's program, the spill response teams are more effective in spill response. The data shows a steady improvement, in the response and also in the MMSevaluations.

This information will improve oil spill response around the world becausethe world looks to the MMS for guidance, and leadership in conducting safe, andenvironmentally sound, oil and gas exploration.
Norwegian Deepwater Program: Damping of Vortex-Induced Vibrations
Authors: Vikestad Kyrre , Larsen Carl M. , Vandiver J. Kim
Published: March 2009

Vortex-induced vibration (VIV) of a long riser in sheared current is oftenconsidered as an energy balance problem: Excitation forces in the power-inregion add an equal amount of energy to the system as is dissipated by dampingforces outside this region and by structural damping. A riser may havedifferent excitation and damping regions depending on the actual oscillationfrequency, cross-section properties and local flow velocity. A damping modelmust hence be able to handle higher and lower flow velocities than theexcitation velocity range. In this paper the fluid damping models proposed by Venugopal [1] are compared with the experiments conducted by Gopalkrishnan [2]and Vikestad [3]. The results show that the models are conservative at high andlow reduced velocities.

Introduction

VIV is dependent on many factors such as the Reynolds number, flow velocity andturbulence of the incident current, surface roughness, cross-section shape, inclination, motion of the structure, etc. No solutions or models exist whichcan account for all these factors.

The solution has therefore been to simplify the interaction problem as muchas possible hopefully without loosing the information important for theprediction of the resulting VIV and fatigue life of the riser. One suchsimplification is to assume that each cross-section along the riser isoscillating harmonically in the cross-flow direction only and that the incidentflow is constant in time. Then the fluid forces can be split into two parts; the inertia part in phase with the acceleration and the excitation/damping partin phase with the velocity of the cross-section. If the force in phase withvelocity has the same sign as the velocity it is excitation, if it has oppositesign it is damping.

In this paper we compare the damping model presented by Venugopal [1] toother experiments. The model predicts the damping force for oscillations instill water, at velocities lower than the excitation velocity range, and athigher. The Venugopal model was based on published empirical damping data fromsub-critical flow experiments. In this paper the Venugopal model is furthertested against the experimental data gathered by Vikestad [3]. The model wasfound to be slightly conservative in that it tends to underestimate thedamping, but not overly so.
Environmental chemical study of the Murucupi river – Barcarena, PA, Brazil impacted area for the aluminum production
Authors: Pereira Simone Pinheiro , Lima Maurício Araújo , Freitas K'Ellen Heloizy , Mescouto Cleide Samara , Saraiva Augusto Fonseca
Published: March 2009

The present work evaluate the chemical conditions of the Murucupi river with relationship to the physical-chemical parameters and the presence of chemical elements in the water and correlations. The Murucupi river is located in the amazon region close the aluminum production area. Were analyzed the major, minor and trace elements (Ca, Mg, Na, K, Fe, Al, Ba, Mn, Sr, Zn, Ni, Pb e Cu), and physical-chemical parameters, acidity, total alkalinity, organic matter, pH, turbidity, temperature, conductivity, dissolved oxygen (OD) and total hardness. 13 collection points were selected along this river. In relation to the physical-chemical parameters the pH and OD only presented values in non conformity with the strip of values established by the resolution 357/05 of CONAMA. In relation to the chemical elements were found only the aluminum (Al: 356.04µg/L) and the iron (Fe: 1080.80µg/L), were in non conformity with the legislation. This results shows the anthropogenic influence in the contamination of the Amazon rivers from the production of aluminum reject.
Isolation of Dense Core Secretory Vesicles from Pancreatic Endocrine Cells by Differential and Density Gradient Centrifugation
Authors: Hutton John C. , Wong Randall , Davidson Howard W.
Published: March 2009

Methods are presented for the separation of dense core secretory vesicles from insulin‐secreting tissues (insulin granules) based on a combination of differential and density gradient centrifugation on various media. Emphasis is given to the use of transplantable tumors, tissue culture cell lines, and pancreatic islets as a tissue source. Curr. Protoc. Cell Biol. 42:3.32.1‐3.32.20. © 2009 by John Wiley & Sons, Inc.
Risk Communication
Authors: Turner Monique Mitchell , Turner Shawn S.
Published: March 2009

The ability to develop, execute, and assess effective risk communication strategies is a vital responsibility for organizations engaged in helping consumers become and stay informed about homeland security issues. Incomplete, conflicting, or complex information can lead to uncertainty, anxiety, and altered perceptions of the realities surrounding risk‐laden events. In order to explicate the challenges associated with effective risk communication, strategies used to relay information to the public about avian bird flu are examined. Best practices for effective risk communication are forwarded and future directions are suggested.
Cyber‐Security
Authors: Cukier Michel , Panjwani Susmit
Published: March 2009

The threat against the nation's critical infrastructure has evolved from a pure physical threat to a combination of physical and cyber‐security threat. The proliferation of networked information infrastructures and the Internet have changed the way critical infrastructures are assessed, managed, and utilized, exposing the nation's critical infrastructure to a new type of threat, namely a cyber‐security threat. The federal government has acknowledged the gravity of the threat leading to the need for risk‐based approaches to measure and alleviate the cyber‐security threat. The core of a risk‐based approach lies in the ability to form and evaluate hypotheses about security. In this article, we describe how empirical data can be utilized to quantify hypotheses about security. We first focus on the link between port scans and attacks and empirically quantify the assumption that scans are precursors to attacks. We divide the data set into malicious traffic originating inside of the organization (calledinternal traffic) and malicious traffic originating from outside of the organization (calledexternal traffic). The first study confirms that just using the number of malicious connections is insufficient for obtaining detailed information on the malicious activity. Then we focus on the most frequently targeted ports. Since the type of malicious activity is linked to the targeted port, we illustrate that internal malicious traffic differs greatly from external malicious traffic.
Developing Medical Countermeasures to Emerging Biothreats
Authors: Gronvall Gigi Kwik
Published: March 2009

This article describes the challenges to development of medical countermeasures posed by emerging biothreat agents. If medical countermeasures—vaccines, therapeutics, or diagnostic tests—are available, they could potentially save lives after a biological weapons attack or during a natural disease outbreak. Currently, however, the costs, technical challenges, and time required to develop and produce countermeasures would leave most potential countermeasures unavailable in a public health emergency. This article describes the current US government strategy for developing medical countermeasures for emerging health threats and biodefense in spite of these hurdles, as well as the strategy for a “flexible defense” to both broaden countermeasure availability and speed development.
Vulnerability Assessment Methodologies for Interdependent Systems
Authors: Townsend Wade R.
Published: March 2009

Vulnerability assessments are crucial in identifying and mitigating risks at a facility, community, state, regional, or national level. Traditional vulnerability assessment methodologies generally focused solely on physical security. The US Department of Energy, Office of Energy Assurance (DOE/OEA) and the US Department of Homeland Security, Office of Infrastructure Protection (DHS/IP) have developed vulnerability assessment methodologies that integrate physical security, operational security, cyber security, and interdependencies element areas together. The interdependencies element considers infrastructure dependencies, interdependencies (modeling a system of systems), and systems' effects (e.g. upstream and downstream system operations, supply chain analysis). For this article, the term interdependencies take on a more holistic and broader definition and perspective. By including the interdependencies element area, vulnerability assessments provide a broader and crosscutting perspective to assist in evaluating risk. Specific interdependencies questions are identified to help assessment teams conduct assessments. The interdependencies questions developed are also applicable to other analysis areas that benefit from broadening scope through interdependencies considerations.
Developing Risk Metrics to Estimate Risks of Catastrophic Biological and Bioterrorist Events: Applications to the Food Industry
Authors: Mohtadi Hamid
Published: March 2009

If the food sector is attacked, the likely agents will be chemical, biological or radionuclear (CBRN). This article provides an overview of ongoing research on international terrorist/criminal activity involving such agents. The issue is the ability to calculate the likelihood of rare but catastrophic risks and in this case, the risk of a catastrophic terrorist attack. The analysis is based on using a statistical method known as
extreme value statistics
to estimate this risk. The article argues that such a method is an appropriate tool for studying high impact, low frequency events. The pronounced nonstationary patterns within the data suggest that the “reoccurrence period” for such attacks is decreasing every year. Similarly disturbing trends are evident in a broader dataset which is nonspecific as to the methods or means of attack.
Cyber Security Standards
Authors: Scarfone Karen , Benigni Dan , Grance Tim
Published: March 2009

The goal of cyber security standards is to improve the security of information technology (IT) systems, networks, and critical infrastructures. A cyber security standard defines both functional and assurance requirements within a product, system, process, or technology environment. Well‐developed cyber security standards enable consistency among product developers and serve as a reliable metric for purchasing security products. Cyber security standards cover a broad range of granularity, from the mathematical definition of a cryptographic algorithm to the specification of security features in a web browser, and are typically implementation independent. A standard must address user needs, but must also be practical since cost and technological limitations must be considered in building products to meet the standard. Additionally, a standard's requirements must be verifiable; otherwise, users cannot assess security even when products are tested against the standard.
Security of Distributed, Ubiquitous, and Embedded Computing Platforms
Authors: Wood Anthony D. , Stankovic John A.
Published: March 2009

As embedded computer systems continue to explode in number and capability, security and privacy challenges abound. We review desirable security properties and the design constraints posed by these systems that make security difficult. We summarize current research by focusing on solutions for ad hoc networks, wireless sensor networks, and RFID tags as representative of the design space. State‐of‐the‐art protocols and approaches for defeating or mitigating attacks at the physical, network and middleware layers are presented. Critical application areas and research needs are identified, as are possible funding sources.
Radioactive Materials Sensors
Authors: Mayo R. M. , Stephens D. L.
Published: March 2009

Providing technical means to detect, prevent, and reverse the threat of potential illicit use of radiological or nuclear materials is among the greatest challenges facing contemporary science and technology. In this short article, we provide a brief description and overview of the State‐of‐the‐art in sensor development for the detection of radioactive materials, as well as an identification of the technical needs and challenges faced by the detection community. We begin with a discussion on γ ray and neutron detectors and spectrometers, followed by a description of imaging sensors, active interrogation, and radiation detection materials' development, before closing with a brief discussion on the unique challenges posed in fielding sensor systems.
Sensing Dispersal of Chemical and Biological Agents in Urban Environments Article
Authors: Ervin Angela M. , Hultgren Anne E. , Rhyne Edward P. , Ward Keith B.
Published: March 2009

The technologies, performance characteristics, and concepts for operational architectures for both chemical and biological agent detection sensors designed to be used in urban environments are discussed. The sensor technologies are categorized by the responses that would be initiated as a result of a positive signal from the sensors, which range from low consequence actions, such as changing building airflows, to high consequence actions, such as the quarantine of areas and distribution of medical countermeasures. Also discussed are the needs for future sensor development efforts. The description of particular technology solutions or detection architectures in this article does not imply the official endorsement of those specific approaches by the Department of Homeland Security.
Dynamic Load Balancing for Robust Distributed Computing in the Presence of Topological Impairments
Authors: Hayat Majeed M. , Pezoa Jorge E. , Dietz David , Dhakal Sagar
Published: March 2009

The purpose of any distributed computing system (DCS) is to offer a flexible, reliable, and powerful computing platform. With the advances in mobile computing, wireless communications and sensor networks, DCSs have emerged in new applications such as wireless sensor networks (WSNs), military battlefield awareness, surveillance and threat detection, to name a few. These new application areas introduce new challenges to DCSs when operated or deployed in harsh or threat‐prone environments. For instance, in WSNs deployed in a military battlefield, the computing elements (CEs) of a DSC join and leave the DCS at any time in a stochastic fashion. More generally, factors such as limited or intermittent communication resources and power constraints or long‐term physical damage of the CEs, can result in random topological changes in the DCS, which, in turn, can severely degrade their performance and reliability. Many of these factors can be attributable to physical attacks on our information infrastructure, of which weapons of mass destruction (WMD) is an important example. This observation has triggered government agencies, such as the Defense Threat Reduction Agency, to launch research initiatives in network science to understand the extent of damage that can be inflicted upon networks in the event of attacks and also to develop strategies to increase the robustness of networks when a threat is present. In this article, we review modern dynamic load balancing (DLB) techniques and their mathematical stochastic models that can be exploited by DCS developers to increase the DCS's robustness to random topological changes, and at the same time, to use the available computing resources of the system efficiently, in the presence of communication uncertainty and CE dysfunction. Two scenarios are considered: one where CEs can fail and recover at random instants and another where CEs can fail permanently. Under the first scenario, we look for minimizing the average response time of a given application. In the second scenario, the goal is to maximize the probability of running an entire application successfully. DLB policies are tested using a small‐scale DCS environment and compared to theoretical predictions as well as results from Monte Carlo simulations. The mathematical probabilistic model presented here for network performance is general and can be applied to a broad class of networks and applications.
Highly Selective Palladium‐Catalyzed Oxidative Csp2Csp3 Cross‐Coupling of Arylzinc and Alkylindium Reagents through Double Transmetallation
Authors: Jin Liqun , Zhao Yingsheng , Zhu Lizheng , Zhang Heng , Lei Aiwen
Published: March 2009

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Using desyl chloride (2‐chloro‐1,2‐diphenylethanone) as the oxidant, the palladium‐catalyzed reaction of arylzinc with alkylindium reagents occurred smoothly in a highly selective manner to afford the products in 57–90% yields. Preliminary kinetic data indicated that alkylindium reagents were highly favored for transmetallation with the alkoxy‐palladium moiety.
The first two Japanese cases of severe type I congenital plasminogen deficiency with ligneous conjunctivitis: Successful treatment with direct thrombin inhibitor and fresh plasma
Authors: Suzuki Takashi , Ikewaki Junko , Iwata Hiroki , Ohashi Yuichi , Ichinose Akitada
Published: March 2009

A 71‐year‐old woman and her elder sister developed ligneous conjunctivitis after ocular surgery. Laboratory tests demonstrated that the proband and her sister had 6.6% and 8.1% of plasminogen activity, and 1.2 and 1.4 mg/dl of antigen, respectively. Thus, they were diagnosed as having severe type I plasminogen deficiency, for the first time, in Japan. DNA sequencing and PCR‐RFLP analyses revealed that these two cases are homozygotes of a novel A‐to‐G mutation at the obligatory splicing acceptor site in intron‐C. Both cases were satisfactorily treated with a direct thrombin inhibitor, topical Argatroban, and topical plasma obtained from their healthy family members. Am. J. Hematol. 2009. © 2009 Wiley‐Liss, Inc.
Effect of occupation and smoking on respiratory symptoms in working children
Authors: Cakir Erkan , Uyan Zeynep S. , Varol Nezih , Ay Pinar , Ozen Ahmet , Karadag Bulent , Ersu Refika , Karakoc Fazilet , Dagli Elif
Published: March 2009

Objectives

To compare the respiratory symptoms and the lung function of children who work in different occupational groups.

Methods

The study was performed among children attending vocational training centers. The participants were evaluated in six different occupation groups. Chronic cough, wheezing and shortness of breath were evaluated by questionnaire. The association of independent variables with the respiratory symptoms was investigated through both univariate and multivariate methods.

Results

Among 642 children, 534 were males; the mean age was 17.7 ± 1.0 years. Using an internal reference group, the odds ratios of chronic cough were significantly higher in the lathe (OR: 2.0, 95%CI: 1.07–3.74), coiffure (OR: 1.94. 95%CI: 1.01–3.70), and electricity‐construction (OR: 2.63, 95%CI: 1.06–6.54) groups after adjustment for smoking, age, gender, and work characteristics. There were no significant differences in spirometric values between occupational groups in either smoking or non‐smoking males. In non‐smoking females, median values of FEV1 (P: 0.046), PEF (P: 0.005) and FEF25–75% (P: 0.019) were lower in the textile compared to the coiffure group. There was no significant association between the total working time and spirometric values. There was no statistically significant relationship between the work‐related factors and the smoking status.

Conclusions

The prevalence of chronic cough was higher in the lathe, coiffure, and electricity‐construction groups and pulmonary function tests were lower in the non‐smoking textile female group. Working children should be screened for respiratory symptoms and disease. Am. J. Ind. Med. 52:471–478, 2009. © 2009 Wiley‐Liss, Inc.
Allelic heterogeneity in inbred populations: The Saudi experience with Alström syndrome as an illustrative example
Authors: Aldahmesh Mohamed A. , Abu‐Safieh Leen , Khan Arif O. , Al‐Hassnan Zuhair N. , Shaheen Ranad , Rajab Mohammed , Monies Dorota , Meyer Brian F. , Alkuraya Fowzan S.
Published: March 2009

The increased frequency of rare autosomal recessive conditions in genetically isolated populations is a well‐established phenomenon. This genetic isolation is invoked as an explanation when one particular mutation is the sole or most frequent mutation observed in a given population and is referred to as the founder effect. This trend of allelic homogeneity is contrasted by an opposite trend when the consanguinity factor is in play. Independent of endogamy at the population level, a consanguineous union is sufficient to render homozygous a percentage of the genome that is directly correlated with the degree of consanguinity. Assuming the gene in question has a normal mutation rate, the resulting homozygosity will inevitably include different defective alleles of that gene. By reporting four novel alleles, we use Alström disease to exemplify the interesting observation of allelic heterogeneity for a very rare autosomal recessive disorder in a highly inbred population. While we frequently assume founder effect in inbred populations, this report should serve to remind us of the powerful effect of the consanguinity factor, a common confounding variable among some of those populations. © 2009 Wiley‐Liss, Inc.
A Mechanism of Efficient G6PD Inhibition by a Molecular Clip
Authors: Kirsch Michael , Talbiersky Peter , Polkowska Jolanta , Bastkowski Frank , Schaller Torsten , de Groot Herbert , Klärner Frank‐Gerrit , Schrader Thomas
Published: March 2009

In die Zange genommen: Eine synthetische molekulare Klammer bindet Nicotinamidadenindinucleotidphosphat (NADP+) (siehe Bild) und besetzt zudem sowohl die Cofaktor‐ als auch die Substratbindestelle in Glucose‐6‐phosphat(G6P)‐Dehydrogenase. Diese Kombination zweier Inhibitionsmechanismen macht die Klammer hoch effektiv und selektiv für dieses Enzym gegenüber anderen Dehydrogenasen.

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Rational Construction of 2D and 3D Borromean Arrayed Organic Crystals by Hydrogen‐Bond‐Directed Self‐Assembly
Authors: Men Yong‐Biao , Sun Junliang , Huang Zhi‐Tang , Zheng Qi‐Yu
Published: March 2009

Borromäische organische Gitter: Das starre trigonal‐pyramidale Molekül 1,3,5‐Tris(4‐carboxyphenyl)adamantan (TCA) bildet über Wasserstoffbrücken ein borromäisch verknüpftes 2D‐Gitter. Verschiedene Linker (Methanol, Phenazin, 4,4′‐Bipyridin und 4,4′‐Azopyridin) führen zu komplexeren Borromäischen Gittern oder gar zu einem polycatenierten 3D‐Gitter.

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Die Gestalt zukünftiger Germaniumcluster
Authors: Korber Nikolaus
Published: March 2009

Aus der Reihe getanzt: Die Existenz endohedraler Germaniumcluster ist schon früher durch Gasphasenexperimente vorausgesagt worden. Das nun synthetisierte [Co@Ge10]3− überrascht, weil es die lange Reihe der zuvor gefundenen, ausschließlich deltaedrischen Strukturen abreißen lässt. Es hat vielmehr eine regelmäßige pentagonal‐prismatische Struktur (siehe Bild; grau Co, rot Ge).

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Gold Nanorod/Fe3O4 Nanoparticle “Nano‐Pearl‐Necklaces” for Simultaneous Targeting, Dual‐Mode Imaging, and Photothermal Ablation of Cancer Cells
Authors: Wang Chungang , Chen Jiji , Talavage Tom , Irudayaraj Joseph
Published: March 2009

Gold and pearls: Multifunctional nanoparticles, each composed of a single, amine‐modified gold nanorod, decorated with multiple “pearls” of Fe3O4 nanoparticles capped with carboxy groups, are prepared. Their effectiveness in simultaneous targeting, dual‐mode imaging, and photothermal ablation of breast cancer cells is demonstrated.

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Thiostannate Tin–Tin Bond Formation in Solution: In Situ Generation of the Mixed‐Valent, Functionalized Complex [{(RSnIV)2(μ‐S)2}3SnIII2S6]
Authors: Hassanzadeh Fard Zohreh , Müller Christian , Harmening Thomas , Pöttgen Rainer , Dehnen Stefanie
Published: March 2009

In broad daylight: The double‐decker thiostannate [(RSnIV)4S6] (1, R=CMe2CH2COMe) condenses to form [{(RSnIV)2(μ‐S)2}3SnIII2S6] (2; see picture). This mixed‐valent complex, which formally contains both SnIII and SnIV atoms as confirmed by Mössbauer spectroscopy and DFT calculations, forms by a complicated, concerted mechanism. Additionally, 2 provides six carbonyl groups for further derivatization.

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Undulated Multicompartment Cylinders by the Controlled and Directed Stacking of Polymer Micelles with a Compartmentalized Corona
Authors: Fang Bing , Walther Andreas , Wolf Andrea , Xu Youyong , Yuan Jiayin , Müller Axel H. E.
Published: March 2009

Like a bamboo rod: Long, bamboo‐like undulated cylinders with distinct branch points and end groups (see picture) were obtained by the stacking of block terpolymer micelles that contain a fluorinated polybutadiene core and a compartmentalized corona of poly(4‐tert‐butoxystyrene) and poly(tert‐butyl methacrylate). Stacking of the polymer micelles, which can be reversed, occurred when the solvent was changed from dioxane to ethanol.

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Rational Construction of 2D and 3D Borromean Arrayed Organic Crystals by Hydrogen‐Bond‐Directed Self‐Assembly
Authors: Men Yong‐Biao , Sun Junliang , Huang Zhi‐Tang , Zheng Qi‐Yu
Published: March 2009

Borromean organic networks: The rigid and trigonal pyramidal molecule, 1,3,5‐tris(4‐carboxyphenyl)adamantane (TCA), self‐assembles into a 2D Borromean linked network by hydrogen bonds. Different linkers (methanol, phenazine, 4,4′‐bipyridine, and 4,4′‐azopyridine) result in more complex Borromean networks or a 3D polycatenation network.

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Bismaleimide‐modified methyl‐di(phenylethynyl)silane blends and composites: Cure characteristics, thermal stability, and mechanical property
Authors: Zhou Quan , Ni LiZhong
Published: March 2009

Reactive blends of organic‐inorganic hybrid monomer, methyl‐di(phenylethynyl)silane (MDPES) and a modified bismaleimide resin (BMI/DBA) have been prepared. The thermal and oxidative stabilities of MDPES‐BMI/DBA blends were characterized by thermogravimetric analysis, derivative thermogravimetry, differential thermal analysis, dynamic mechanical analysis, and flexural strength retention at 240°C. Scanning electron microscopy was employed to study the surface morphology of MDPES‐BMI/DBA composite after thermal oxidative treatment. With the increase of concentration of BMI/DBA, flexural strength of composites increased from 78 to 331 MPa. The results showed that MDPES‐BMI/DBA blends exhibited excellent thermal and thermal oxidative properties, and the interface between MDPES and glass fiber was improved by the incorporation of BMI/DBA. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Synthesis and properties of sulfonated poly(siloxane imide)s bearing dimethyl siloxane oligomers for fuel cell applications
Authors: Chen Xinbing , Chen Pei , Okamoto Ken‐Ichi
Published: March 2009

A series of sulfonated poly(siloxane imide)s (SPSIs) were synthesized from 4,4′‐ketone dinaphthalene 1,1′,8,8′‐tetracarboxylic dianhydride (KDNTDA), a dimethyl siloxane oligomer‐based diamine, and a sulfonated diamine. The reduced viscosities ranged from 1.0 to 3.5 dL/g at 35°C in the triethylamine (TEA) salt form. The SPSIs showed anisotropic membrane swelling with larger swelling in thickness than in plane. They displayed reasonably high proton conductivity, thermal stability and good mechanical properties. The KDNTDA‐based SPSIs showed good solubility in common aprotic solvents not only in TEA salt form but also in proton form. The 1H‐NMR results indicated that the molar content of the dimethyl siloxane oligomer in the SPSIs was 50–80% of that in the feed. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Using organic montormollontrite to reinforce the structure and flexural property of denture base nanocomposites
Authors: Li Zhi‐An , Liu Lijian , Xiao Qun
Published: March 2009

The denture bases nanocomposites were prepared by adding organic montormollontrite(OMMT) into poly(methyl methacrylate) matrix. The resulting composites were characterized by XRD, TEM, and ISTRON 3365 flexural strength testing systems. One‐way analysis of variance and Tukey's test were used to compare the difference in flexural strength and flexural modulus. The results showed the formation of exfoliated‐intercalated and intercalated denture base nanocmposite when the content of OMMT was 3 wt % and 5 wt % in the powder of denture base resin, respectively. The maximum ultimate flexural strength was observed in denture base nanocomposite containing 3 wt % of OMMT and flexural strength decreased with further increases of OMMT content. The flexural modulus of denture base nanocomposite increased continually with OMMT content increasing from 1 wt % to 10 wt %. Significant difference in both flexural strength and flexural modulus was observed between the nanocomposites with 3 wt % OMMT and controls (n = 5, P < 0.05). © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Surface modification of polypropylene microporous membrane by grafting acrylic acid using physisorbed initiators method
Authors: Wang Hui , Yin Yanhong , Yang Shuting , Li Chengbin
Published: March 2009

Surface modification of microporous polypropylene (PP) membrane was performed by graft polymerization of acrylic acid using physisorbed initiators method. The factors effecting on the grafting degree such as monomer concentration, reaction temperature and initiator density were determined. The morphological and microstructure changes of the membrane were characterized by scanning electron microscopy (SEM), atomic force microscopy (AFM), and Fourier transform infrared spectroscopy (FTIR). The pure water contact angle, protein adsorbed amount, water flux, and antifouling property of the grafted membrane were investigated. The results indicated that the pore size and porosity of the grafted membrane were reduced and the static contact angle of pure water on the grafted membrane decreased from 108° to 40° with the increase of grafting degree. The amount of protein adsorbed on the grafted membrane decreased about 30% compared to the virgin polypropylene membrane when the grafting degree was 18.71%. Though the water flux reduced, the flux recovery of the grafted membrane increased 82.66% with the grafting degree 16.0%. The hydrophilic and antifouling property of the grafted membrane also were improved. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Predicting the properties of needlepunched nonwovens using artificial neural network
Authors: Rawal Amit , Majumdar Abhijit , Anand Subhash , Shah Tahir
Published: March 2009

Needlepunching is a well‐known nonwoven process of converting fibrous webs into self‐locking or coherent structures using barbed needles. In this study, Artificial Neural Network (ANN) modeling technique has been used to predict the bulk density and tensile properties of needlepunched nonwoven structures by relating them with the main process parameters, namely, web area density, punch density, and depth of needle penetration. The simultaneous effect of more than one parameter on bulk density and tensile properties of needlepunched nonwoven structures have been investigated based upon the results of trained ANN models. A comparison is also made between the experimental and predicted values of fabric bulk density and tensile strength in the machine and crossmachine directions in unseen or test data sets. It has been inferred that the ANN models have achieved good level of generalization that is further ascertained by the acceptable level of mean absolute error obtained between predicted and experimental results. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Expanded graphite–epoxy composites with high dielectric constant
Authors: Xie Yun‐Chuan , Yu De‐Mei , Min Chao , Guo Xiu‐Sheng , Wan Wei‐Tao , Zhang Jing , Liang Hong‐Lu
Published: March 2009

Composites of an expanded graphite/diglycidyl ether of bisphenol A (DGEBA) were prepared by a simple melt blending method, and their dielectric and mechanical properties were investigated. During observations of fractured surfaces of the composites, the graphite sheets were seen to be homogeneously dispersed in the epoxy matrix. Moreover, the composites presented an enhanced dielectric constant (∼ 180) and a low loss factor (∼ 0.05) at 50 Hz, suggesting their potential suitability for embedded dielectric applications. The enhanced dielectric constant can be explained by the percolation theory and the relatively low loss factor was attributed to strong interfacial interactions between the polymer molecules and the OH/COOH groups of the expanded graphite, which constrained the orientational polarization of the polarons. Furthermore, dynamic mechanical analysis of the composites showed a restricted macromolecular relaxation and improved mechanical properties. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Synthesis and application of a silica nanocomposite filler using water glass and a resole‐type phenol resin
Authors: Matsuzawa Takashi , Mase Katsushi , Inoue Shin‐ichi
Published: March 2009

Composite plastics in which silica was dispersed homogeneously were prepared from a resole‐type phenol resin and a silica‐sol using water glass. The silica (10–50 nm) was dispersed into resin particles of 2–20 μm in size. The powder that was obtained (nanocomposite filler) and a curing reagent were then mixed, and the resulting mixture was processed by using heat and pressure to yield plastics containing nanocomposite fillers. The coefficients of friction factor of the resulting plastics composites decreased by half and the amount of wear that they suffered decreased to just one tenth of that of the unfilled material, while their wear‐resistance was greatly improved. The new plastics displayed good sliding properties, while also maintaining good fluidity. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009