bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Influence of Particle Size Distribution on the Performance of Ceramic Particulate Suspensions
Authors: Rasteiro Maria da Graça , Jorge Albano 
Published: June 2007

AbstractDuring the preparation of ceramic glaze suspensions it is necessary to guarantee that the suspension possesses the required properties, with several parameters having to be rigorously controlled, e.g., particle size and solids concentration, composition of the suspension and ionic charge of the liquid. This study focuses attention on the influence of particle size distribution on three important properties of glaze suspensions: rheological behavior, opacity and reflectance characteristics and tendency to dissolve. In this paper, results are presented for two glaze formulations prepared with two different commercial frits of distinct composition. The glazes were prepared in a laboratory ball mill and the grinding time was adjusted for each formulation, in order to obtain suspensions with different particle size (at least three different grinding times). The rheological behavior is strongly dependent on the particle size and also on changes in the interactions between the particles, caused by modifications in the cationic content of the suspending medium, as a result of frit dissolution, which is also influenced by the size of the particles.
Bioaerosol Analysis by Single Particle Mass Spectrometry
Authors: Kleefsman Ineke , Stowers Michael A. , Verheijen Peter J. T. , Wuijckhuijse Arjan L. van , Kientz Charles E. , Marijnissen Jan C. M. 
Published: June 2007

AbstractThe performance and improvements of an aerosol mass spectrometer for the real time analysis of bioaerosol particles is described. The instrument can preselect the biological aerosol particles from non‐biological particles, by recording the emitted fluorescence when the particles are irradiated with 266 nm laser light. The fluorescing particles are further investigated by mass spectrometry. With the current performance of the mass spectrometer the produced mass spectra have high resolution and cover a mass range up to 85 kDalton. The capability of the aerosol mass spectrometer to produce good quality spectra of bacteria particles is shown with a mass spectrum of Erwinia herbicola. For the application of the aerosol mass spectrometer the possible interference of (background) soot particles onto the preselection is investigated and a minor interference is determined.
Dry Grinding of Mefenamic Acid Particles for Enhancement of its Water Dissolution Rate
Authors: Iwasaki Tomohiro , Takahara Maiko , Sonoda Ryoichi , Watano Satoru 
Published: June 2007

AbstractThis paper details an investigation into the enhancement of the water dissolution rate of mefenamic acid (MA) by means of a dry grinding treatment. The physico‐chemical properties of the ground MA particles were analyzed by measurements of specific surface area, powder X‐ray diffraction patterns, differential scanning calorimetry thermograms and infrared spectra, and the effects of the change in the physico‐chemical properties (especially, crystalline structure) on the dissolution rate were studied. The polymorphic transition from Form I (original) to II and the change of the molecular structure of MA did not occur in the grinding treatments. However, the specific surface area of the MA particles increased, and the crystallinity decreased (i.e., the amorphization level increased) as the grinding progressed. Hydrogen bonds formed between the carboxyl groups of the opposed asymmetric MA molecules were broken gradually after the grinding limit was attained in the grinding system, resulting in an effective improvement of the initial dissolution rate.
Dynamics on the Group Manifold and Path Integral
Authors: Marinov M. S. , Terentyev M. V. 
Published: July 2007

AbstractClassical and quantal dynamics on the compact simple Lie group and on a sphere of arbitrary dimensionality are considered. The accuracy of the semiclassical approximation for Green's functions is discussed. Various path integral representations of Green's functions are presented. The special features of these representations due to the compactness and curvature are analysed. Basic results of the theory of Lie algebras and Lie groups used in the main text are presented in the Appendix.
Gatekeeping procedures with clinical trial applications
Authors: Dmitrienko Alex , Tamhane Ajit C. 
Published: June 2007

AbstractThe objective of this paper is to give an overview of a relatively new area of multiplicity research that deals with the analysis of hierarchically ordered multiple objectives. Testing procedures for this problem are known as gatekeeping procedures and have found a variety of applications in clinical trials. This paper reviews main classes of these procedures, including serial and parallel gatekeeping procedures, and tree gatekeeping procedures that account for logical restrictions among multiple objectives. We focus on procedures based on marginal p‐values; extensions to procedures that exploit the joint distribution of the p‐values are also noted. Clinical trial examples are used to illustrate the procedures and their important properties. Copyright © 2007 John Wiley & Sons, Ltd.
Sample size estimation for non‐inferiority trials of time‐to‐event data
Authors: Crisp Adam , Curtis Paula 
Published: June 2007

AbstractWe consider the problem of sample size calculation for non‐inferiority based on the hazard ratio in time‐to‐event trials where overall study duration is fixed and subject enrolment is staggered with variable follow‐up. An adaptation of previously developed formulae for the superiority framework is presented that specifically allows for effect reversal under the non‐inferiority setting, and its consequent effect on variance. Empirical performance is assessed through a small simulation study, and an example based on an ongoing trial is presented. The formulae are straightforward to program and may prove a useful tool in planning trials of this type. Copyright © 2007 John Wiley & Sons, Ltd.
Simulation, a tool for designing‐in reliability
Authors: Brombacher Aarnout , Van Geest Erik , Arendsen Robert , Van Steenwijk Anne , Herrmann Otto 
Published: July 2007

AbstractThis paper describes a new method for the analysis and optimization of reliability as an integrated part of the design process of electronic circuits. It bases itself on the analysis of the susceptibility of failure mechanisms in components as a function of the combinations of external stress factors (stressor‐sets). The paper describes the backgrounds of stressor‐susceptibility analysis, the need for this analysis and the way this method is used for high‐level design and optimization of electronic circuits.
The impact of electronic components on the reliability of cars
Authors: Kumpfmüller Hans‐Georg 
Published: July 2007

AbstractElectronic control units in automotive applications must meet most demanding quality and reliability requirements. Tomorrow's quality and reliability targets for complete electronic system units are at the same level as those for today's complex components in these units.The analysis of the present situation reveals the essential deficiencies. The required improvements must be based on early partnership of the component supplier and the system manufacturer at the design phase of components and systems, on matured and controlled processes at component and system manufacturing and on correct application of both components and systems.
On the use of DC measurements for ESD‐related process monitoring
Authors: Luchies Jan Marc , Kuper Fred , Verweij Jan 
Published: July 2007

AbstractDC measurements and transmission line method measurements have been carried out on field oxide NMOSTs made in a 0‐8 μm CMOS process. Analysis shows that DC measurements can be applied for fast ESD related feedback to submicron process development.
Analysis of ESD protection networks for DMOS power transistors by means of static and time‐resolved emission microscopy
Authors: Bonati Bruno , Canclini Athos , Cavone Marianna , Novarini Enrico , Pavan Paolo , Rivoir Roberto , Stucchi Michele , Zanoni Enrico 
Published: July 2007

AbstractDifferent ESD input/output protection networks, based on Zener diodes and lateral npn transistors have been implemented with the aim of characterizing their effectiveness in protecting vertical DMOS power transistors. Failure mechanisms have been identified by means of static emission microscopy. Gated emission microscopy, in synchronism with a voltage pulse emulating the ESD event, enables the dynamic behaviour of protection structures to be analysed, identifying lateral current crowding effects which explain the observed failure mechanisms.
Two‐dimensional modelling and characterization of gate‐to‐drain overlap contribution on the leakage current of a MOSFET, used as a GCD
Authors: Ciantar E. , Burgniard S. , Jérisian R. , Oualid J. 
Published: July 2007

AbstractWe have studied the contribution of the gate‐to‐drain overlap on the hot‐carrier induced leakage current of an NMOSFET used as gate‐controlled diode (GCD) after stress. The experimental GCD characteristic is compared to the model obtained by a home‐modified version of MINIMOS. We have introduced an arbitrary or calculated profile of interface states and charges created by hot electrons (models given by C. Hu and P. Roblin, respectively) in order to calculate by fitting their spatial distributions. We have studied also the influence of stress conditions on simulated GCD characteristics.
Enhanced anaerobic bioremediation of a TCE source at the Tarheel Army Missile Plant using EOS
Authors: Borden Robert C. , Beckwith Walter J. , Lieberman M. Tony , Akladiss Naji , Hill Steve R. 
Published: June 2007

AbstractEOS, or emulsified oil substrate, was used to stimulate anaerobic biodegradation of trichloroethene (TCE) and tetrachloroethene (PCE) at a former Army‐owned manufacturing facility located in the Piedmont area of North Carolina. Previous use of chlorinated solvents at the facility resulted in soil and groundwater impacts. Ten years of active remediation utilizing soil vacuum extraction and air sparging (SVE/AS) were largely ineffective in reducing the TCE/PCE plume. In 2002, the Army authorized preparation of an amended Remedial Action Plan (RAP) to evaluate in situ bioremediation methods to remediate TCE in groundwater. The RAP evaluated eight groundwater remediation technologies and recommended EOS as the preferred bioremediation alternative for the site. Eight wells were drilled within the 100 × 100 feet area believed to be the primary source area for the TCE plume. In a first injection phase, dilute EOS emulsion was injected into half of the wells. Distribution of the carbon substrate through the treatment zone was enhanced by pumping the four wells that were not injected and recirculating the extracted water through the injection wells. The process was repeated in a second phase that reversed the injection/extraction well pairs. Overall, 18,480 pounds of EOS were injected and 163,000 gallons of water were recirculated through the source area. Anaerobic groundwater conditions were observed shortly after injection with a corresponding decrease in both PCE and TCE concentrations. Dissolved oxygen, oxidation‐reduction potential, and sulfate concentrations also decreased after injection, while TCE‐degradation products, ferrous iron, and methane concentrations increased. The reduction in TCE allowed the Army to meet the groundwater remediation goals for the site. Approximately 18 months after injection, eight wells were innoculated with a commercially prepared dechlorinating culture (KB‐1) in an attempt to address lingering cis‐1,2‐dichloroethene (cis‐DCE) and vinyl chloride (VC) that continued to be observed in some wells. Dehalococcoides populations increased slightly post‐bioaugmentation. Both cis‐DCE and VC continue to slowly decrease. © 2007 Wiley Periodicals, Inc.
Remediation with cyclodextrin: Recovery of the remedial agent by membrane filtration
Authors: Boving Thomas B. , Barnett Stanley M. , Perez Gustavo , Blanford William J. , McCray John E. 
Published: June 2007

AbstractCyclodextrin‐enhanced flushing of contaminants from the subsurface is a promising innovative remediation technology. It will become more economically viable at more sites if methods can be developed to recover and reconcentrate the cyclodextrin solution after it has been flushed through an aquifer. The goal of this study was to determine if membrane technology is capable of meeting that need. Five membranes with different material properties were tested for this purpose in the laboratory. The results of these tests indicate that there are large differences both in the efficiency of these membranes to extract hydroxpropyl‐β‐cyclodextrin (HPCD) and their stability when exposed to trichloroethylene (TCE) at concentrations near aqueous solubility. Not only does the molecular weigh cutoff (MWCO) of a membrane determine if HPCD can be retained, but crucial selection criteria are the membrane's resistance and compatibility with TCE. Of the five membrane materials tested, only two (polymer composite membrane and polysulfone) met both these requirements. The polymer composite membrane (MPF‐44) showed reliable and stable HPCD recoveries (>95 percent) even when exposed to high TCE concentrations. The polysulfone membrane showed high HPCD recoveries, 88.5 ± 0.4 percent to 97 percent ±1 percent for ultrafiltration and nanofiltration membranes, respectively. However, membrane swelling and deterioration became a problem at high TCE concentrations (>1,000 mg/L). These problems diminished when the TCE concentration was less than 1 mg/L. Field tests demonstrated that batch mode treatment by ultrafiltration doubled the cyclodextrin concentration from 5 to 10 percent within three hours at a constant operating pressure of 13 psi. Under continuous single‐pass treatment conditions, cyclodextrin concentration also increased, although the rate of increase was much smaller than in batch mode. Overall, these tests showed that cyclodextrin recovery is possible under field conditions. © 2007 Wiley Periodicals, Inc.
Remediation process optimization: A status report
Authors: Madabhushi Sriram , O'Neill Tom 
Published: June 2007

AbstractThere are hundreds of contaminated sites with remediation systems that require evaluation and modification to accomplish cleanup goals. These systems are operating well past projected cleanup schedules, cost more than projected to operate, and may not be as protective of human health and the environment as planned. Remediation process optimization (RPO) is an effective method to assess the progress of a system toward achieving cleanup goals within desired time frames and to make the necessary changes in order to reach those goals. Eight main components to the RPO process are evaluated during a review and an implementation plan of recommended changes to the system is developed. Follow‐up and tracking are essential to successful RPO programs. In this article, the authors present a summary of a recent Technical and Regulatory (TechReg) Guidance Document (Interstate Technology and Regulatory Council [ITRC], 2004) and related Technology Overview Series on Advanced Topics in RPO (ITRC, 2006) in a distilled form. © 2007 Wiley Periodicals, Inc.
Evaluation of soil solid amendments for TCE biodegradation in a biobarrier system
Authors: Katsenovich Yelena , Öztürk Zuhal , Allen Marshall , Wein Gary 
Published: June 2007

AbstractPermeable biobarrier systems (PBSs) are being recognized as low‐cost passive bioremediation technologies for chlorinated organic contamination. This innovative technology can play a crucial and effective role in site restorations. Laboratory‐scale experiments were conducted to investigate the biodegradation of trichloroethylene (TCE) to ethylene in shallow groundwater through the use of a PBS enhanced by bioaugmentation at the U.S. Department of Energy's Savannah River Site (SRS). Two composts and two plant amendments, eucalyptus mulch (EM) and corncobs (CC), were examined for their effectiveness at creating and maintaining conditions suitable for TCE anaerobic dechlorination. These materials were evaluated for their (1) nutrient and organic carbon content, (2) TCE sorption characteristics, and (3) longevity of release of nutrients and soluble carbon in groundwater to support TCE dechlorination. Native bacteria in the columns had the ability to convert TCE to dichloroethenes (DCEs); however, the inoculation with the TCE‐degrading culture greatly increased the rate of biodegradation. This caused a significant increase in by‐product concentration, mostly in the form of DCEs and vinyl chloride (VC) followed by a slow degradation to ethylene. Of the tested amendments, eucalyptus mulch was the most effective at supporting the reductive dechlorination of TCE. Corncobs created a very acidic condition in the column that inhibited dechlorination. © 2007 Wiley Periodicals, Inc.
The ART In‐Well Technology test at a chlorinated solvent site in central Iowa
Authors: Donnerberg Cynthia R. , Cleary John P. , Odah Marco M. 
Published: June 2007

AbstractAn Accelerated Remediation Technologies (ART) In‐Well Technology pilot test was performed to evaluate the removal of chlorinated volatile organic compounds (VOCs) from groundwater. The ART In‐Well Technology was installed in one well located in the source area where dense nonaqueous‐phase liquid has been identified and VOC concentrations exceed 140,000 μg/L. Monitoring wells at the site were positioned between 10 and 170 feet from the ART test well. Overall, VOC concentrations from samples collected from the groundwater monitoring wells and in the vapors extracted for discharge from the ART treatment well were analyzed over the testing period. Monitoring results showed that concentrations of perchloroethylene were reduced in the closest monitoring well to nondetectable concentrations within 90 days. The cumulative removal of chlorinated VOCs from the ART test well over the six‐month pilot test period exceeded 9,500 pounds based on air monitoring data. The ART technology proved effective and cost‐efficient in reducing contaminant concentrations and removing a large mass of contamination from the subsurface in a short period of time. The radius of influence of the ART technology at the site was estimated to range between 65 and 170 feet. © 2007 Wiley Periodicals, Inc.
Monitored natural attenuation forum: The use of carbon isotope analysis at MNA sites
Authors: Paul Philp R. , Pirkle Robert J. , McLoughlin Patrick W. , Peacock Aaron D. , Yang Xiaomin 
Published: June 2007

AbstractStable carbon isotopes have been used in various applications for approximately 50 years, in many applications including the fields of medicine, criminology, and biology and recently has been used in the remediation field to track the degradation of various organic compounds. It is a commercially available investigation technology that is gaining in popularity and has unique applications related to monitored natural attenuation (MNA). To further discuss this technology and how it is used at MNA sites, we presented the following question to five guest panel members. © 2007 Wiley Periodicals, Inc.
Effects of bottom sediment restoration on interstitial habitat characteristics and benthic macroinvertebrate assemblages in a headwater stream
Authors: Sarriquet P. E. , Bordenave P. , Marmonier P. 
Published: June 2007

AbstractThe restoration of in‐stream habitats by structural improvement of stream beds is more and more frequent, but the ecological consequences of such works are still little known. We have examined the influence of the deposit of a 15 cm gravel layer over the stream bottom on the chemical characteristics of the interstitial water, the sediment grain size and the composition of the benthic assemblages. We have compared a restored reach to an upstream control over three years and at three seasons each year. Dissolved oxygen, ammonium, nitrite and nitrate contents were measured in both surface and interstitial (−15 cm deep) waters, together with the depth of anoxia estimated using wooden stakes and fine sediment content at the surface. During the same period and seasons, benthic invertebrates were sampled at five points in each reach. The restoration induced an increase in vertical exchanges of water between surface and interstitial habitats, with an increase in the depth of hypoxia. Changes were observed in the composition of invertebrate communities, but not in the density or in the taxonomic richness of assemblages. These changes in assemblages were fragile: a local disturbance (such as a drying period) diminished the beneficial effect of the restoration with the disappearance of several organisms. The viability of such restoration works may be associated with catchment management designed to reduce fine sediment inputs to the river. Copyright © 2007 John Wiley & Sons, Ltd.
A parallel optimization algorithm for minimum execution‐time multiprocessor scheduling problem
Authors: Kasahara Hironori , Itoh Atsusi , Tanaka Hisamitsu , Itoh Keisuke 
Published: July 2007

AbstractThis paper proposes a parallel optimization algorithm PDF/IHS for the minimum execution‐time multiprocessor scheduling problem which is a strong NP‐hard optimization problem. PDF/IHS is a parallelization and efficient implementation of the only practical optimization algorithm DF/IHS among those which have been proposed for this scheduling problem. In PDF/IHS, processors perform depth‐first search in parallel on a heuristically generated search tree in such a way that it is searched hierarchically from the left‐ and right‐hand sides.The effectiveness of PDF/IHS has been verified by simulation and practical parallel processing on Alliant FX4. As a result, it has been recognized that most of the problems which required a long time by DF/IHS can be solved approximately in time 1/m by PDF/IHS using m processors. Moreover, even for a problem which required a very long time or could not be solved in a practical time by DF/IHS, it has been verified that PDF/IHS can give solutions in time less than 1/m.
Nanostructuring with a Crosslinkable Discotic Material
Authors: Kastler Marcel , Pisula Wojciech , Davies Richard J. , Gorelik Tatiana , Kolb Ute , Müllen Klaus 
Published: June 2007

AbstractA high‐yielding synthesis afforded a hexa‐peri‐hexabenzocoronene carrying acrylate units at the end of six attached alkyl spacers. The polymerization of these acrylate moieties could be initiated with thermal energy and through direct photoactivation without the addition of a photoinitiator. This allowed the organization of the liquid‐crystalline material to be fixed in either the crystalline state or the mesophase, which preserved the organization in the respective phase. The use of a focused synchrotron beam permitted selected regions of a thin film to be rendered insoluble. After “developing” the film in this lithographic process by dissolving the soluble, unpolymerized material, defined nano‐objects remained on the substrate. In addition, the pronounced aromatic π stacking of the novel material allows an organization in mesoporous membranes that could be fixed by thermal crosslinking. After the removal of the inorganic template, mechanically stable nanotubes were obtained, which were characterized by different microscopy techniques.