bluuebunny/crossref_metadata_2025 huggingface dataset:
Effects of injection location, flow ratio and geometry on kenics mixer performance
Authors: Hobbs D. M. , Muzzio F. J.
Published: June 2004

The performance of the Kenics static mixer for mixing small streams of passive tracer into the bulk flow is investigated as a function of injection location and flow ratio. Flow ratios of 1/99 and 10/90 are simulated at nine different injection locations, and two alternative geometries are considered in addition to the standard Kenics mixer. Mixing is evaluated qualitatively by examining the spread of the tracer on cross‐sectional slices from the mixer and quantitatively by computing the variation coefficient as a function of axial position. For the standard Kenics geometry, injection location strongly affects the extent of mixing only for the first few elements, after which the mixing rate is independent of injection location. In a sufficiently long mixer, material injected at any location spreads to the entire flow, but the least effective injection locations require up to four elements more than the most effective locations to achieve the same variation coefficient. A faster rate of decrease in variation coefficient is observed for a flow ratio of 1/99 us. 10/90. An alternative geometry in which the elements have 120° of twist instead of the standard 180° of twist shows a similar dependence on injection location and flow ratio, but is more energy‐efficient than the standard Kenics geometry. In another alternative geometry in which all elements have the same direction of twist, segregated islands exist in the flow. For injection locations inside the segregated islands, virtually no mixing takes place; for injection locations outside of the segregated islands, the tracer spreads to the remaining flow but does not penetrate the islands.
Plantwide control design procedure
Authors: Luyben Michael L. , Tyreus Bjorn D. , Luyben William L.
Published: June 2004

Plantwide control involves the systems and strategies required to control an entire chemical plant consisting of many interconnected unit operations. A general heuristic design procedure is presented that generates an effective plantwide control structure for an entire complex process flowsheet and not simply individual units. The nine steps of the proposed procedure center around the fundamental principles of plantwide control: energy management; production rate; product quality; operational, environmental and safety constraints; liquid‐level and gas‐pressure inventories; makeup of reactants; component balances; and economic or process optimization. Application of the procedure is illustrated with three industrial examples: the vinyl acetate monomer process, the Eastman plantwide‐control process, and the HDA process.
Fundamental continuous‐pulp‐digester model for simulation and control
Authors: Wisnewski Philip A. , Doyle Francis J. , Kayihan Ferhan
Published: June 2004

A model of a continuous digester was developed as an extension of the well‐known Purdue model. A lumped‐parameter approximation is used to describe the flow transport mechanism of the digester, and a model based on the fundamental principles of mass and energy is derived. Mass bases and volume fractions are defined to allow fewer simplifying assumptions in the model derivation than in previous model versions. The steady‐state profiles and dynamic responses of the digester model are compared with a previous version of the Purdue model, and the significant differences between the two models are highlighted. The digester model is also compared to the Weyerhaeuser benchmark digester model, and a parametric sensitivity analysis to several model parameters is performed. Physical explanations are given for the demonstrated model behaviors. Model implementation is straightforward, making it useful for process control, optimization and design studies.
New autosomal recessive syndrome with short stature and facio–auriculo–thoracic malformations
Authors: Mégarbané André , Daou Linda , Mégarbané Hala , Cave Hélène , Chouery Eliane , Verloes Alain
Published: June 2004

Two sibs, a boy and a girl, from a Lebanese consanguineous family presented with short stature, microcephaly, ptosis, small, dysplastic, low set ears, short neck, and pectum excavatum and carinatum. In addition, the boy had a high arched palate, a cardiac malformation, and at the X‐rays an absence of fusion of the posterior hemi‐arches of C7 and a fusion between L5 and S1 with a sagittal‐cleft vertebral body of L5, while his sister had a cleft lip/palate and at the X‐rays an abnormal odontoid peg and a malformation of the articular facets between C1 and C2, and bilateral cervical ribs. Other laboratory and radiological investigations were normal. Sequencing of PTPN11 exons 2, 3, 4, 7, 8, 12, and 13 did not reveal any variations. Two other sibs presented almost the same dysmorphic features; one girl died at age 6¼ years after an acute episode of renal insufficiency, and one boy died at 40 days of age. Differential diagnosis is discussed and the possibility of the report of a new autosomal recessive syndrome with variable expressivity is raised. © 2004 Wiley‐Liss, Inc.
Effect of the inclusion of PEG on the solid‐state properties and drug release from polylactic acid films and microcapsules
Authors: Jonnalagadda Sriramakamal , Robinson Dennis H.
Published: June 2004

The use of poly(lactic acid) (PLA) for controlled drug delivery applications was limited by unfavorable physical properties such as hydrophobicity, high intrinsic crystallinity, low permeability, and high glass transition temperatures. This research used polyethylene glycols (PEGs) of varying molecular weights (300–18,500 g/mol) and concentrations (0–50% w/w) to modify the permeability, intrinsic crystallinity, glass transition temperature, residual solvent levels, and release of a model drug, 5‐flurouracil (5FU), from monolithic films and microcapsules fabricated with PLA. The films were fabricated by solvent casting from methylene chloride. The microcapsules were formed by a coacervation method by using a methylene chloride/hexane solvent/nonsolvent system. Compared to PLA films, all PLA : PEG films showed the following: (1) a glass transition temperature between 40 and 55°C, (2) 5–8% lower residual solvent levels, and (3) enhanced permeability to 5FU. These results suggested that the incorporation of PEG improves the physical properties of PLA films to enable fabrication of controlled release delivery systems. Similar to the films, incorporation of PEG also enhanced the permeability of PLA microcapsules to 5FU. However, high intrinsic crystallinity, dual endothermal character for PLA melting, and significant burst release of 5FU in PLA : PEG microcapsules may limit their development for controlled drug delivery applications. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 93: 2025–2030, 2004
Reactive microspheres as active fillers for epoxy resins
Authors: Carfagna C. , Ambrogi V. , Cicala G. , Pollicino A. , Recca A. , Costa G.
Published: June 2004

Physical properties of epoxy resins filled with microparticles are presented and discussed. Microparticles were synthesized in the form of micron‐sized, crosslinked spherical particles, with an excess of reactive amino groups on their outer surface, and subsequently blended with EPON828‐3,3′DDS in different weight percents (10 and 20 wt %). Differential scanning calorimetry and scanning electronic microscopy were applied to investigate microsphere properties such as morphology, shape, size, and size distribution. Electron spectroscopy for chemical analysis was applied on particles to relate surface composition and reactivity of microspheres. Rheological, dynamic–mechanical, and mechanical properties of the cured blends were analyzed and related to the pure resin and to the same resin modified with PES180. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 93: 2031–2044, 2004
Chemiluminescence detection of Escherichia coli in fresh produce obtained from different sources
Authors: Mathew Finny P. , Alagesan Deepa , Alocilja Evangelyn C.
Published: June 2004

A chemiluminescence‐based assay is developed for the rapid detection of Escherichia coli in fresh produce. The assay was based on the reaction of β‐galactosidase enzyme from E. coli with a phenylgalactosidase‐substituted dioxetane substrate. Light emitted from the reaction was measured in a luminometer and data correlated with counts of E. coli enumerated on sorbitol–MacConkey agar plates. A strain of E. coli O157:H7 was used to inoculate samples of fresh produce to differentiate the inoculum from the natural E. coli potentially present on the produce. Fresh market samples were tested for generic E. coli and E. coli O157:H7. Signiﬁcant differences in light emission were found in samples with high initial E. coli counts when market samples were compared to respective heat‐treated samples. The assay was able to detect E. coli in all produce tested, particularly at higher contamination or inoculation levels. The sensitivity of the assay ranged between 102–105 CFU within 30 min. The chemiluminescence assay provides a simple and rapid method for detection of viable E. coli, an important step towards enhancing food safety. Copyright © 2004 John Wiley & Sons, Ltd.
Damage control in the abdomen and beyond
Authors: Loveland J A , Boffard K D
Published: June 2004

Background

Damage control is not a modern concept, but the application of this approach represents a new paradigm in surgery, borne out of a need to care for patients sustaining multiple high-energy injuries.

Methods

A Medline search was performed to locate English language articles relating to damage control procedures in trauma patients. The retrieved articles were manually cross-referenced, and additional academic and historical articles were identified.

Results and conclusion

Damage control surgery, sometimes known as ‘damage limitation surgery’ or ‘abbreviated laparotomy’, is best defined as creating a stable anatomical environment to prevent the patient from progressing to an unsalvageable metabolic state. Patients are more likely to die from metabolic failure than from failure to complete organ repairs. It is with this awareness that damage control surgery is performed, enabling the patient to maintain a sustainable physiological envelope.
Simultaneous determination of some active ingredients in anti‐viral preparations of traditional Chinese medicine by micellar electrokinetic chromatography
Authors: Chen Xiaofeng , Zhang Jiyou , Xue Chunxia , Chen Xingguo , Hu Zhide
Published: June 2004

A simple and rapid micellar electrokinetic chromatography method was developed for the simultaneous determination of quercetin, gentiopicrin, forsythin, chlorogenic acid and caffeic acid in anti‐viral preparations of traditional Chinese medicine (apTCM). In this method, the effects of buffer pH, concentration of the borax and SDS, organic modiﬁers, applied voltage and temperature on the separation were tested and discussed. The results showed that the ﬁve analytes could be well separated within 11 min under conditions of 40 mm borax (pH 9.65) containing 20 mm SDS, 20 kV, at 25°C. In the tested concentration range, regression equations revealed good linear relationships (correlation coefﬁcients 0.9920–0.9991) between the peak areas and corresponding concentrations. In addition, a multiple linear regression QSPR model was constructed to predict the migration times of the analytes and the results were satisfactory. The method was validated by analysis of the ﬁve compounds in three representative apTCM samples with recoveries ranging from 89.2 to 106.6%. Copyright © 2004 John Wiley & Sons, Ltd.
Physiological and intravascular ultrasound assessment of an ambiguous left main coronary artery stenosis
Authors: Leesar Massoud A. , Masden Ronald , Jasti Venu
Published: June 2004

The angiographic assessment of an ambiguous left main coronary artery (LMCA) stenosis is often difficult and not reliable. Intravascular ultrasound (IVUS) and fractional flow reserve (FFR) have improved the diagnostic utility of an ambiguous LMCA stenosis. The combined role of FFR and IVUS in patients with an ambiguous LMCA stenosis is discussed. Catheter Cardiovasc Interv 2004;62:349–357. © 2004 Wiley‐Liss, Inc.
Elective sirolimus‐eluting stent implantation for left main coronary artery disease: Six‐month angiographic follow‐up and 1‐year clinical outcome
Authors: Arampatzis Chourmouzios A. , Lemos Pedro A. , Hoye Angela , Saia Francesco , Tanabe Kengo , van der Giessen Willem J. , Smits Pieter C. , McFadden Eugene , de Feyter Pim , Serruys Patrick W.
Published: June 2004

The effectiveness of sirolimus‐eluting stent (SES) implantation in patients treated electively for left main (LM) stenoses has not been yet ascertained. The present study reports on the clinical and angiographic outcome of 16 consecutive patients treated electively for de novo stenoses in the LM. The impact of SES implantation on major adverse cardiac events was evaluated. Mean age was 65 ± 11 years. Unprotected LM was present in nine (56%), and eight patients (50%) received stents extending into both the left anterior descending and circumflex arteries for stenoses of the distal left main bifurcation. In‐house mortality and reintervention rate was zero. One patient developed a non‐Q‐wave myocardial infarction related to the index procedure. At 1‐year clinical follow‐up, there were no deaths or further myocardial infarctions; one (6%) patient required target lesion revascularization. A total of 12 patients (75%) underwent 6‐month angiographic follow‐up with a late lumen loss of 0.04 ± 0.65 mm and one focal restenosis (8% of patients). Elective SES implantation for LM disease was associated with zero mortality and a very low incidence of additional major adverse events at 1 year. Catheter Cardiovasc Interv 2004; 62:292–296. 2004 Wiley‐Liss, Inc.
Slide‐based cytometry and predictive medicine: The 8th Leipziger workshop and the 1st international workshop on slide‐based cytometry
Authors: Sack Ulrich , Bocsi Jozsef , Tárnok Attila
Published: June 2004

Slide‐based cytometry (SBC) and related techniques offer unique tools to perform complex diagnostic procedures at very early disease stages. Multicolor or polychromatic analysis of cells by SBC is of special importance, not only as a cytomics technology platform, but for patients with low blood volume such as neonates. The exact knowledge of the location of each cell on the slide allows the specimen to be restained and subsequently reanalyzed. These separate measurements can be fused to one data file (merging), increasing the information obtained per cell. Relocalization and optical evaluation of the cells, a typical feature of SBC, can be of integral importance for cytometric analysis. Predictive medicine is aimed at the detection of changes in the patient's state prior to the manifestation of deterioration or improvement. Such instances are concerned with multiorgan failure in sepsis or noninfectious posttraumatic shock in intensive care patients, or the pretherapeutic identification of high risk patients in cancer cytostatic therapy. Early anti‐infectious or anti‐shock therapy, as well as curative chemotherapy in combination with stem cell transplantation, may provide better survival chances for the patient as well as concomitant cost containment. Predictive medicine–guided, individualized, early reduction or cessation of therapy may lower or abrogate potential therapeutic side effects (individualized medicine). With the 8th Leipziger Workshop and the 1st International Workshop on Slide‐Based Cytometry, cytomics technologies moved to more practical applications in the clinics and the clinical laboratory. This development will be continued in 2004, at the upcoming Leipziger Workshop and the International Workshop on Slide‐Based Cytometry. © 2004 Wiley‐Liss, Inc.
Quantitative trait loci (QTL) analysis reveals a close linkage between the hinge region and trimeric IgA dominancy in a high IgA strain (HIGA) of ddY mice
Authors: Oida Emi , Nogaki Fumiaki , Kobayashi Ikei , Kamata Tadashi , Ono Takahiko , Miyawaki Shigeki , Serikawa Tadao , Yoshida Haruyoshi , Kita Toru , Muso Eri
Published: June 2004

Polymerization of IgA has been suggested as one of the causes of mesangial deposition in IgA nephropathy. HIGA mice are an inbred model of IgA nephropathy, established by selective mating of ddY mice. This strain is characterized by a unique profile of the IgA molecule that is dominantly polymeric and has high serum levels with intense IgA deposition on the mesangium. We carried out quantitative trait loci (QTL) analysis, using F2 generations by crossing HIGA with BALB/c mice. Significant linkage of polymeric IgA in serum samples was identified around D12Mit263, which is close to the gene of the immunoglobulin heavy chain on chromosome 12. The amino acid sequence of the α heavy chain revealed marked differences between BALB/c and HIGA mice. Furthermore, most differences were focussed on the hinge region. The DBA/2J strain, which has the same amino acid sequence in the hinge region as the HIGA strain, also showed polymeric IgA dominance but low IgA levels in sera. Size fraction analysis revealed that these polymeric IgA showed trimer dominance in both DBA/2J and HIGA mice. In conclusion, the hinge region plays a key role in trimeric IgA formation in HIGA mice.
Characterization of HLA‐DR‐ and TCR‐binding residues of an immunodominant and genetically permissive peptide of the 16‐kDa protein of Mycobacterium tuberculosis
Authors: Caccamo Nadia , Meraviglia Serena , La Mendola Carmela , Bosze Szylvia , Hudecz Ferencz , Ivanyi Juraj , Dieli Francesco , Salerno Alfredo
Published: June 2004

The16‐kDa protein of Mycobacterium tuberculosis represents an important antigenic target during bacillary latency and, consequently, should be considered as candidate subunit vaccine component. In this study, we have used CD4 T cell clones that recognize the peptide p91–110, an immunodominant and genetically permissive epitope, in the context of five different HLA‐DR molecules and truncated and substituted variants of this peptide, to identify the minimal binding sequence (HLA‐DR‐binding core) and the minimal stimulatory sequence (TCR‐binding core), as well as the residuesthat contact HLA‐DR molecules and the TCR. We have found a common 9‐mer sequence, spanning amino acids 93–101, as the binding core for HLA‐DR1, ‐DR11, ‐DR13 and ‐DR7, but a longer (13‐mer) sequencespanning amino acids 92–104 was required for binding to the HLA‐DR15 molecules. F93 was required for binding to all the tested HLA‐DR molecules, hence allowing us to identify it as the N‐terminal primary anchor residue (P1). Additionally, the binding requirements for other residues varied considerably between the tested alleles: A94 for HLA‐DR15, V99 for HLA‐DR1, ‐DR15, ‐DR11 and ‐DR7, R100 for HLA‐DR11 and ‐DR13, and L104 for HLA‐DR15. Concerning the residues of p91–110 peptide required for binding to the TCR, the pepscan analysis results would support the contention that P(–1) E92, P6 F98 would be important TCR contact sites because their substitutions led to full loss of T cell activation. Moreover, P8 R100 is found to be critical residue in binding to HLA‐DR11‐ and ‐DR13‐restricted T cell clones, without influencing binding to the relevant HLA‐DR molecule. Our results could be useful to design peptides with altered HLA anchor residues or TCR interaction sites to achieve remarkable increase in activity and to study their vaccine potential.
Synthesis, Structures and Catalytic Properties of Bis(2‐pyridylimino)‐ isoindolatopalladium Complexes
Authors: Siggelkow Bettina , Meder Markus B. , Galka Christian H. , Gade Lutz H.
Published: June 2004

Reaction of the bis(2‐pyridylimino)isoindole derivatives (10‐Me)‐BPI (1a), (11‐Me)‐BPI (1b), (11‐Br)‐BPI (1c), (4‐Me)‐BPI (1d) and 4‐Me‐10‐tBuBPI (1e) with [PdCl2(PhCN)2] and triethylamine in benzene gave the square‐planar palladium(II) complexes [PdCl{(10‐Me)‐BPI}] (2a), [PdCl{(11‐Me)‐BPI}] (2b), [PdCl{(11‐Br)‐BPI}] (2c), [PdCl(4‐MeBPI)] (2d) and [PdCl(4‐Me‐10‐tBuBPI)] (2e), respectively. Extraction of the crude product 2b with aqueous sodium carbonate solution led to the formation of the dinuclear carbonato‐bridged complex [{(11‐Me‐BPI)Pd}2(μ‐CO3)] (3) which was characterized by an X‐ray structure analysis. Reaction of 11‐Br‐BPI (1c) with a large excess (6 equiv.) of the acetylenes Me3SiCCH, Ph3SiCCH and PhCCH under Sonogashira conditions gave the alkynylated derivatives 11‐(Me3SiCC)‐BPI (4a), 11‐(Ph3SiCC)‐BPI (4b) and 11‐(PhCC)‐BPI (4c), which were metallated with bis(benzonitrile)dichloropalladium(II) to yield the PdII complexes [PdCl{11‐(Me3SiCC)‐BPI}] (5a), [PdCl{11‐(Ph3SiCC)‐BPI}] (5b) and [PdCl{11‐(PhCC)‐BPI}] (5c), respectively. The activity of 2b in the catalytic hydrogenation of C=C double bonds was tested for the reaction with styrene, 1‐octene and cyclohexene. The stability of the palladium complex, the reproducibility of the reaction kinetics, the different behaviour towards the three olefins chosen as substrates, as well as the possibility of isolating the non‐decomposed catalyst after several catalytic runs, provides circumstantial evidence for molecular catalysis with the BPI‐palladium complexes. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)
Cover Picture: Cobalt‐Mediated Cyclooligomerization Reactions of Borylacetylenes (Eur. J. Inorg. Chem. 13/2004)
Authors: Goswami Avijit , Maier Claus‐Jürgen , Pritzkow Hans , Siebert Walter
Published: June 2004

The cover picture shows the molecular structure of a (1,3‐diboryl‐2,4‐diphenylcyclobutadiene)(cyclopentadienyl)cobalt complex obtained in an attempt to trimerize 1‐(dithiocatecholboryl)‐2‐phenylacetylene with CpCo(CO)2. Details are discussed in the article by W. Siebert et al. on p. 2635 ff.
A 4‐year epidemiological study of typical and atypical eating disorders: preliminary evidence for subgroups of atypical eating disorders with different natural outcomes
Authors: Cotrufo P. , Monteleone P. , Castaldo E. , Maj M.
Published: June 2004

Backgrounds

We designed a two‐step prospective study aiming to detect cases with full and atypical eating disorders (EDs) in a population of female high‐school students (first step) and to assess their natural outcome after a 4‐year time period (second step).

Methods

In the first step, we screened female students in their first year of high school by means of the EDI‐2 and GHQ‐28 questionnaires. Those students identified as being at risk for an ED underwent a psychiatric interview. In the second step, 4 years later, we tested schoolgirls in their last year of high school by adopting the same procedure as the first step.

Results

140 subjects participated in both steps. In the first step, we identified one subject with full‐blown bulimia nervosa (BN), one with partial‐syndrome BN, two with subclinical BN and eight with subclinical anorexia nervosa (AN). At the reassessment 4 years later, none of the girls had received any form of help. The full‐blown BN case, the partial‐syndrome BN case and one of the subclinical AN cases persisted unchanged; one of the subclinical BN cases shifted to subclinical AN; the remaining subclinical cases remitted spontaneously. Moreover, we identified 12 new cases of EDs.

Conclusions

Present findings provide the first evidence that subclinical AN and subclinical BN represent unstable states that can spontaneously remit over time. Copyright © 2004 John Wiley & Sons, Ltd and Eating Disorders Association.
Anorectic symptomatology as a prodrome of schizophrenia: four case reports
Authors: Kelly Lisa , Kamali Moayyad , Brennan Thomas
Published: June 2004

We describe four patients who originally presented with a diagnosis of adolescent anorexia nervosa and were subsequently diagnosed with schizophrenia. Overt positive symptoms of schizophrenia emerged during the course of treatment for the eating disorder. Symptoms such as social withdrawal and reduced work or academic performance, which had previously been attributed to the eating disorder, we considered to be negative symptoms of schizophrenia. We hypothesize that anorectic symptomatology may have represented prodromal features of schizophrenia in these patients. The clinical implications are discussed. Copyright © 2004 John Wiley & Sons, Ltd and Eating Disorders Association.
Enhanced inhibitive effects of combination of rofecoxib and octreotide on the growth of human gastric cancer
Authors: Tang Chengwei , Liu Chunlun , Zhou Xuchun , Wang Chunhui
Published: June 2004

Our previous studies indicated that cyclooxygenase‐2 inhibitor or octreotide could suppress the proliferation of gastric adenocarcinoma in vitro or in vivo. The present study was aimed to find whether rofecoxib combined with octreotide could enhance the inhibitive effects on the growth of gastric cancer. The effect of rofecoxib or octreotide on proliferation of gastric cancer cell line was determined by 3H‐thymidine ribotide incorporation. The TdT‐mediated dUTP nick end‐labeling assay was used to detect the apopotosis. To determine their synergic antineoplastic effects, the interaction between rofecoxib and octreotide on SGC‐7901 cell was evaluated by the median effect plot. After orthotopical implantion of xenografts of human gastric cancer in stomach, nude mice were given rofecoxib plus octreotide for 8 weeks. Cyclooxygenase‐2 in gastric cancer tissues was measured by immunohistochemistry. Combination of rofecoxib and octreotide presented synergistic effect (combination index < 1) in the majority of responses. The inhibitory rate for xenografts in nude mice was 89.7% in rofecoxib group. Combination of rofecoxib and octreotide enhanced inhibitory rate to 98.8%. The combination greatly increased the apoptotic index (78.20% ± 6.45%) of the xenografts as compared with that of using rofecoxib alone (46.60% ± 3.42%); the difference was very significant (p < 0.001). Rofecoxib could inhibit the activity of cyclooxygenase‐2 in the tissue of gastric adenocarcinomas of nude mice. Our results indicate that combination of rofecoxib and octreotide significantly enhances the antiproliferative effect in gastric adenocarcinoma, which might have potential therapeutic value. © 2004 Wiley‐Liss, Inc.
Multiple mechanisms of action of ZR2002 in human breast cancer cells: A novel combi‐molecule designed to block signaling mediated by the ERB family of oncogenes and to damage genomic DNA
Authors: Brahimi Fouad , Rachid Zakaria , Qiu Qiyu , McNamee James P. , Li Yu‐Jiang , Tari Ana M. , Jean‐Claude Bertrand J.
Published: June 2004

The mechanism of action of ZR2002, a chimeric amino quinazoline designed to possess mixed EGFR tyrosine kinase (TK) inhibitory and DNA targeting properties, was compared to those of ZR01, a reversible inhibitor of the same class and PD168393, a known irreversible inhibitor of EGFR. ZR2002 exhibited 4‐fold stronger EGFR TK inhibitory activity than its structural homologue ZR01 but was approximately 3‐fold less active than the 6‐acrylamidoquinazoline PD168393. It preferentially blocked EGF and TGFα‐induced cell growth over PDGF and serum. It also inhibited signal transduction in heregulin‐stimulated breast tumour cells, indicating that it does not only block EGFR but also its closely related erbB2 gene product. In contrast to its structural homologues, ZR2002 was capable of inducing significant levels of DNA strand breaks in MDA‐MB‐468 cells after a short 2 hr drug exposure at a concentration as low as 10 μM. Reversibility studies using whole cell autophosphorylation and growth assays in human breast cell lines showed that in contrast to its reversible inhibitor counterpart ZR01, ZR2002 induced irreversible inhibition of EGF‐stimulated autophosphorylation in MDA‐MB‐468 cells and irreversible inhibition of cell growth. Moreover despite possessing a weaker binding affinity than PD168393, it induced a significantly more sustained antiproliferative effect than the latter after a pulse 2 hr exposure. More importantly, in contrast to ZR01 and PD168393, ZR2002 was capable of inducing significant levels of cell death by apoptosis in MDA‐MB‐468 cells. The results in toto suggest that the superior antiproliferative potency of ZR2002 may be due to its ability to induce a protracted blockade of receptor tyrosine kinase‐mediated signaling while damaging cellular DNA, a combination of events that may trigger cell‐killing by apoptosis. © 2004 Wiley‐Liss, Inc.
Synthesis of low‐shrinkage polymerizable liquid‐crystal monomers
Authors: Satsangi Neera , Rawls H. Ralph , Norling Barry K.
Published: June 2004

Polymerization shrinkage remains a major barrier to the universal use of resin restorative in large posterior cavity preparations. A new bifunctional liquid crystal (LC) monomer, 2‐(t‐butyl), 1,4‐bis‐[4‐(6‐acryloxy‐hexane‐1‐oxy)‐benzoyloxy] benzene, with exceptionally low polymerization shrinkage, has recently been discovered. The purpose of this communication is to report a new, easy, high‐yield synthetic route to synthesize this compound in comfortable larger batches. Synthetic and isolation details, chemical characteristics, and the polymerizable properties of a new structurally related by‐product monomer, namely, 2‐(t‐butyl),1‐[4‐(6‐acryloxy‐hexane‐1‐oxy)‐benzoyloxy], 4‐[4‐{6‐(3‐acryl oxy‐propionoxy)‐hexane‐1‐oxy}‐benzoyloxy]‐benzene, is also reported. The structural confirmation of this by‐product indicates that it resulted from the Michael‐type addition of acrylate ion on one of the terminal acryloxy groups of 2‐(t‐butyl), 1,4‐bis‐[4‐(6‐acryloxy‐hexane‐1‐oxy)‐benzoyloxy] benzene. The by‐product itself, as well as the natural blend of the aforesaid both products as formed in the reaction mixture, also polymerized at room temperature with lesser volume shrinkage as compared to the conventional control (GTE) at similar degrees of conversion. © 2004 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 71B: 153–158, 2004
Denitrification in aqueous FeEDTA solutions
Authors: van der Maas Peter , Harmsen Loes , Weelink Sander , Klapwijk Bram , Lens Piet
Published: June 2004

The biological reduction of nitric oxide (NO) in aqueous solutions of FeEDTA is an important key reaction within the BioDeNOx process, a combined physico‐chemical and biological technique for the removal of NOx from industrial flue gasses. To explore the reduction of nitrogen oxide analogues, this study investigated the full denitrification pathway in aqueous FeEDTA solutions, ie the reduction of NO3−, NO2−, NO via N2O to N2 in this unusual medium. This was done in batch experiments at 30 °C with 25 mmol dm−3 FeEDTA solutions (pH 7.2 ± 0.2). Also Ca2+ (2 and 10 mmol dm−3) and Mg2+ (2 mmol dm−3) were added in excess to prevent free, uncomplexed EDTA. Nitrate reduction in aqueous solutions of Fe(III)EDTA is accompanied by the biological reduction of Fe(III) to Fe(II), for which ethanol, methanol and also acetate are suitable electron donors. Fe(II)EDTA can serve as electron donor for the biological reduction of nitrate to nitrite, with the concomitant oxidation of Fe(II)EDTA to Fe(III)EDTA. Moreover, Fe(II)EDTA can also serve as electron donor for the chemical reduction of nitrite to NO, with the concomitant formation of the nitrosyl‐complex Fe(II)EDTA–NO. The reduction of NO in Fe(II)EDTA was found to be catalysed biologically and occurred about three times faster at 55 °C than NO reduction at 30 °C. This study showed that the nitrogen and iron cycles are strongly coupled and that FeEDTA has an electron‐mediating role during the subsequent reduction of nitrate, nitrite, nitric oxide and nitrous oxide to dinitrogen gas. Copyright © 2004 Society of Chemical Industry
Reliable production of highly concentrated bioethanol by a conjunction of pervaporation using a silicone rubber sheet‐covered silicalite membrane with adsorption process
Authors: Ikegami Toru , Kitamoto Dai , Negishi Hideyuki , Iwakabe Koichi , Imura Tomohiro , Sano Tsuneji , Haraya Kenji , Yanagishita Hiroshi
Published: June 2004

For the production of highly concentrated bioethanol by pervaporation using an ethanol‐permselective silicalite membrane, pervaporation performance was investigated using a silicalite membrane entirely covered with a silicone rubber sheet to prevent direct contact with acidic compounds. By using a resistance model for membrane permeation, the separation factor of the covered silicalite membrane towards ethanol can be estimated from the individual pervaporation performances of the silicalite membrane and the silicone rubber sheet. No decrease in the ethanol concentration through the silicone rubber sheet‐covered membrane was caused when ethanol solutions containing succinic acid were supplied. By directly passing the permeate‐enriched ethanol vapor mixed with water vapor through a dehydration column packed with a molecular sieve of pore size 0.3 nm, highly concentrated bioethanol up to 97% (w/w), greater than the azeotropic point in the ethanol/water binary systems, can be obtained from 9% (w/w) fermentation broth. Copyright © 2004 Society of Chemical Industry
The probabilistic key‐group method
Authors: Yarahmadi Bafghi A. R. , Verdel T.
Published: June 2004

Key‐block approaches are widely used in the analysis of rock slopes. The key‐group method improves such analyses by taking into account groups of blocks instead of single blocks. Nevertheless, these stability analyses are usually carried out within a context where uncertainty may be a difficult problem to overcome. In the present paper, we propose introducing probabilistic approaches into the key‐group method in order to account for uncertainty in the mechanical parameters of the problem to be solved. Both the first‐order, second‐moment method (FOSM) and the advanced second‐moment method (ASMM) are considered herein and compared with Monte‐Carlo simulations through the use of five theoretical case studies. Lastly, the probabilistic key‐group method (PKGM) is qualified. Copyright © 2004 John Wiley & Sons, Ltd.
Modified modal methods for calculating eigenpair sensitivity of asymmetric damped system
Authors: Moon Yeong‐Jong , Kim Byoung‐Wan , Ko Man‐Gi , Lee In‐Won
Published: June 2004

Many real systems such as moving vehicles on roads, missiles following trajectories and ships in sea water have asymmetric mass, damping and stiffness matrices. Eigen‐sensitivity analysis methods for the symmetric damped system cannot be used in the asymmetric damped case. Therefore, a method for calculating eigenpair sensitivity of the asymmetric damped system is needed. To do this, a modal method employing a modal superposition idea was recently developed. Since the accuracy of the modal method is dependent on the number of modes used in calculation, the modal method needs higher eigenvectors to guarantee the accuracy. In large‐scale systems, however, only a few lower modes are generally considered for the dynamic analysis. Hence, if the modal method is used to obtain the eigen‐sensitivity of the large‐scale system, the significant errors could not be avoided due to the lack of the information of higher modes. In this paper, the modified modal methods for computing the sensitivities of the eigenpairs of asymmetric damped system using a few lowest sets of modes are proposed. Numerical example shows that the proposed methods achieve better calculating efficiency than the previous modal method. Copyright © 2004 John Wiley Sons, Ltd.
Polymerization of pyrrole by isopolymetallates of vanadium/molybdenum and preparation of a polypyrrole–molybdenum blues nanocomposite
Authors: Ballav Nirmalya , Biswas Mukul
Published: June 2004

Oxidative polymerization of pyrrole (PY) was achieved in high yield (>90 %) by adding the monomer directly to isopolyvanadate (IPV) and isopolymolybdate (IPMo) solutions at selected pH. In the case of the IPV solution instantaneous precipitation of a black mass was obtained while in the IPMo solution in situ precipitation of polypyrrole (PPY) onto molybdenum blues (MB) formed through reduction of IPMo by PY resulting in a PPY‐encapsulated MB nanocomposite (PPY–MB). Formation of PPY was confirmed from Fourier‐transform infrared (FTIR) and thermogravimetric (TG) analyses. Transmission electron microscope (TEM) photographs for the composite revealed the formation of spherical particles of average size ≈75 nm. Scanning electron microscope (SEM) analyses showed the distinctive morphological patterns for PPY and PPY–MB composite. The direct current conductivity values for PPY prepared by IPV, IPMo and PPY–MB were of the order of 10−2, 10−4 and 10−6 S cm−1, respectively. Copyright © 2004 Society of Chemical Industry
Synthesis and characterization of acetylated syndiotactic polystyrene
Authors: Gao Yong , Li Hua‐Ming
Published: June 2004

Acetylation of highly stereoregular syndiotactic polystyrene has been accomplished in a heterogeneous process by using carbon disulfide as the dispersing medium, and acetyl chloride and anhydrous aluminium chloride as acetylating agent and catalyst, respectively. The acetylation reaction can be well controlled and carried out to a high degree of acetylation. The resultant polymer was characterized by FTIR and NMR spectroscopy. The incorporation of acetyl groups into syndiotactic polystyrene was found to have an effect on the thermal properties of these new materials. The degree of crystallinity was decreased by the presence of acetyl groups, while the glass transition temperature increased. Copyright © 2004 Society of Chemical Industry
Homogeneous graft copolymerization of chitosan with methyl methacrylate by γ‐irradiation via a phthaloylchitosan intermediate
Authors: Liu Li , Li Yu , Zhang Wei‐an , Zhang Guoqing , Fang Yue‐e
Published: June 2004

The graft copolymerization of methyl methacrylate (MMA) onto chitosan was tried via a new protection‐graft‐deprotection procedure. Because the intermediate phthaloylchitosan was soluble in organic solvents, the graft copolymerization was carried out in a homogeneous system. Grafting was initiated by γ‐irradiation. The graft percentage extent was dependent on the irradiation dose and the concentration of MMA monomer, and copolymers with grafting above 100 % were readily prepared. The graft copolymers exhibited a high affinity not only for aqueous acid but also for some organic solvents. Differential scanning calorimetry measurements revealed the presence of a glass transition phenomenon, which could be ascribed to the poly(methyl methacrylate) side‐chains. Copyright © 2004 Society of Chemical Industry
Nanocomposites of polymer gel electrolyte based on poly(ethylene glycol diacrylate) and Mg–Al layered double hydroxides
Authors: Cho Mi Suk , Shin Bora , Nam Jae Do , Lee Youngkwan , Song Kigook
Published: June 2004

The present paper describes the synthesis and characterization of nanocomposite materials composed of the polymer gel electrolyte and a layered double hydroxide (LDH) inorganic filler. Mg–Al LDHs were prepared with various ratios of Mg/Al. It was observed that the layered structure of Mg–Al LDH was totally exfoliated by the PEGDA. The ionic conductivity and mechanical strength were highly improved in the nanocomposite systems. In the case of the composite films having 4.5 wt% of the Mg–Al LDH, the ionic conductivity reached 1.6 × 10−3 S cm−1 at room temperature. The incorporation of nanoparticles into the gel resulted in a two‐ or threefold increase in the tensile modulus. Copyright © 2004 Society of Chemical Industry
Epoxy/clay nanocomposites: further exfoliation of newly modified clay induced by shearing force of ball milling
Authors: Lu Hai‐jun , Liang Guo‐Zheng , Ma Xiao‐yan , Zhang Bao‐yan , Chen Xiang‐bao
Published: June 2004

To induce montmorillonite (MMT) to be further exfoliated and homogeneously dispersed in epoxy matrix (diglycidyl ether of bisphenol A) curing in the presence of diaminodiphenyl sulfone and obtain improved mechanical properties, a promising new method has been developed to prepare highly reinforced epoxy/MMT nanocomposites through exerting shearing force on epoxy/MMT solution by ball milling. Modifying agents, being combined with dodecylbenzyldimethylammonium chloride and meta‐xylylenediamine, were used to organically modify the clay (MMTII). Different resultant products were characterized by Fourier‐transform infrared spectroscopy, X‐ray diffraction, transmission electron microscopy, etc, and the fracture surface of the mechanically tested specimens was also observed by scanning electronic microscopy. Results show that the novel MMTII possess a reactive interaction surface with the epoxy matrix. Exfoliation of the retained sandwich structure (being intercalated) or large agglomerates (undispersed MMTII) can be promoted by external shearing force of ball milling, and homogeneously dispersed MMTII nano‐sheets in epoxy matrix nanocomposites are typically observed. Mechanical properties, especially impact toughness, can be increasingly enhanced by the newly structured MMTII and ball milling. Impact strength is increased up to 48.1 kJ m−2 from 32.1 kJ m−2 at 3 wt% MMTII content, which is about 50 % higher than that of pristine matrix, and the flexural strength can also be enhanced by about 8 % higher. Copyright © 2004 Society of Chemical Industry
Influence of lanthanide triflate compounds on formation of networks from DGEBA and γ‐butyrolactone
Authors: Mas Cristina , Mantecón Ana , Serra Angels , Ramis Xavier , Salla Josep Maria
Published: June 2004

Diglycidylether of bisphenol A (DGEBA) was cured with γ‐butyrolactone (γ‐BL) using different lanthanide triflates as catalysts. Fourier transform infrared spectroscopy was used to study the different evolutions of the four elemental processes that took place during curing with lanthanum and ytterbium triflates. The greatest differences among the lanthanides were in oxophilicity and Lewis acidity. Differences in the coordination ability of the metal to the monomers were shown and according to the Pearson theory, were related to their different characteristics. Differences in the reactivity of the systems were related to the differences in the Lewis acidity of the initiators. The evolution of the contraction during curing using different lanthanide triflates was monitored by thermomechanical analysis. All systems showed that contraction took place in two stages and that there was an intermediate region, associated with gelation, with no contraction. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 3782–3791, 2004
Surface grafting onto SiC nanoparticles with glycidyl methacrylate in emulsion
Authors: Luo Ying , Rong Min Zhi , Zhang Ming Qiu , Friedrich Klaus
Published: June 2004

To improve the tribological performance of nano‐SiC particles filled epoxy composites, surface modification of the fillers is necessary. By means of soapless emulsion polymerization method, graft polymerization of glycidyl methacrylate (GMA) onto the surface of alkyl nano‐SiC was carried out, resulting in composite particles with SiC core and polymeric shell in which polyglycidyl methacrylate (PGMA) is chemically attached to the nanoparticles by the double bonds introduced during the pretreatment with a coupling agent. By analyzing the reaction mechanism, the emulsion polymerization loci were found to be situated at the SiC surface. Also, the factors affecting the grafting yielding of PGMA on the particles were investigated, including monomer concentration, initiator consumption, reaction temperature, reaction time, etc. Accordingly, an optimum grafting reaction condition was determined. It was shown that the grafted nanoparticles exhibit greatly improved dispersibility in good solvent for the grafting polymer. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 3842–3852, 2004
Venting of gaseous explosions
Authors: Mercx W. P. M. , van Wingerden C. J. M. , Pasman H. J.
Published: June 2004

An experimental investigation has been performed into the venting of methane‐air explosions in heating plants. The investigation was performed on a realistic scale in a 38.5 m3 enclosure. The first part of the experimental program concerns the influence of the “usual” parameters such as the vent opening area, the vent opening pressure, the ignition location and the vent opening configuration. The second part of the investigation concerns the influence of factors related to heating plants. Thus the effect of introducing a large obstacle, that is the central heating apparatus, and the effect of venting through a dormer window (heating plants are often located in the cellar of a building allowing explosion venting via a dormer window only) are investigated.
The effect of oxygen on vinyl acetate and acrylic monomer stabilization
Authors: Levy Leon B.
Published: June 2004

Vinyl acetate monomer and acrylic acid and its esters are stabilized with phenolic polymerization inhibitors. Oxygen is needed for these stabilizers to work effectively in acrylic monomers, but is not necessary for vinyl acetate monomer, and actually destabilizes it at elevated temperatures.
Data summary of the national fire protection association's BLEVE tests
Authors: Melhem G. A. , Croce P. A. , Abraham H.
Published: June 2004

In conjunction with the production of a new film entitled BLEVE Update®2, the National Fire Protection Association (NFPA) sponsored a series of six Boiling Liquid Expanding Vapor Explosion (BLEVE) tests using 1.893 m3 propane tanks. The purpose of the experiments was to obtain film footage of BLEVEs and to compile test data and documentation that might help to better define failure mechanisms and other important physical processes involved. The experiments included tests with simulated pool fires and tests with liquid and gaseous flame jets. The fill level of each tank was varied for the six experiments. The tanks were instrumented with thermocouples and pressure transducers in both the liquid and vapor space. This paper describes the test setup and summarizes the data measurements obtained.
The determination of compatibility via thermal analysis and mathematical modeling
Authors: Hofelich T. C. , Frurip D. J. , Powers J. B.
Published: June 2004

New regulations in 1991 (HM‐183) have required that materials may not be coshipped in the same cargo tank motor vehicle if, as a result of their mixing “…an unsafe condition would occur, such as an explosion, fire, excessive increase of pressure or heat or the release of toxic vapors.”

In order to determine the potential hazards resulting from inadvertent mixing which would result in a hazardous condition, a technically sound evaluation procedure was needed which was reasonably accurate as well as time and cost effective. This required both thermodynamic (heat and/or pressure released) and kinetic parameters (is the energy released immediately or does it take a day, week, month etc.?). A model has been developed using the SimuSolv

A Trademark of the Dow Chemical Co.

computer program and Microsoft's EXCEL™ spreadsheet which combines the kinetics and thermodynamics for a reaction with the heat transfer parameters for a given tanker truck. Real heat loss data were then obtained for a typical compartmentalized tanker truck for use in the model. The rates and enthalpies for reaction input can be taken from ARC, DSC, or literature data. Since a very large number of binary combinations of potentiai mixtures are possible, materials were grouped according to chemical functionality. A model compound was chosen to represent each functional group. These materials were chosen to best represent the worst‐case reactivity of the group, unimpeded by steric or other factors. A single material/formulation could be classified into more than one grouping. Representative data were complied from experimental studies (Mixing calorimetry, ARC, DSC, etc.) and a wide variety of internal and external literature sources. Where outside sources described a potential incompatibility between groups, the data were gathered on model compounds and input into the model to determine pertinent compatibility. A compatibility chart was constructed for the resulting potential binary mixtures based upon these results.