bluuebunny/crossref_metadata_2025_split huggingface dataset:
Enzymatic hydrolysis of nylon 6 fiber using lipolytic enzyme
Authors: Kiumarsi Amir , Parvinzadeh Mazeyar 
Published: February 2010

AbstractThis study confirms the structural changes of nylon 6 fibers using lipase by measuring the dyeability, hydrophilicity, chemical changes, and fastness properties. For this purpose, nylon 6 fabrics were first treated separately with different concentrations of lipase enzyme. The dyeing process was then carried out on the treated fabrics with two disperse and acid dyes. A UV‐vis spectrophotometer was used for determination of dyebath exhaustion. Acid and disperse dyes showed higher dyebath exhaustion on the enzyme treated samples compared to raw material. The intensity of major peaks in FTIR spectra of the lipase treated samples are in favor of chemical changes of the polypeptide functional groups in fabric. Tensile strength of treated fabrics was decreased due to enzyme treatment. The results of color measurements in the CIELAB system showed that the darkness of the samples increased with an increase in the enzyme percentage in the solution. The results of moisture regain showed that treatment of nylon fabrics with lipolytic enzymes caused to increase the moisture absorbency. The wash and light fastness properties of samples were measured according to ISO 105‐CO5 and Daylight ISO 105‐BO1 and discussed. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Visualization of bubble dynamics in foam injection molding
Authors: Mahmoodi Mehdi , Behravesh Amir H. , Rezavand S. A. Mohammad , Pashaei Amir 
Published: February 2010

AbstractThis article presents a visualization study on nonisothermal bubble growth and collapse in the foam injection molding process (FIM). Observation study can give more insight to the bubble growth in foaming process, especially in the challenging injection foaming process. In this study, besides the growth of bubbles, collapse of the bubbles was also observed which could provide knowledge to the final foam morphology. Cell growth vs. time was recorded and analyzed using a software‐equipped high speed camera. To investigate the cell collapse, various holding pressure was exerted on the gas‐charged molten polymer. The amount of holding pressure had noticeable effect on the rate of bubble collapse. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Study of compatibility, morphology structure and mechanical properties of CPVC/ABS blends
Authors: Zhang Li‐Xin , Zhou Chao , Sun Shu‐Lin , Ren Liang , Ma Xiao‐Lin , Zhang Ming‐Yao , Zhang Hui‐Xuan 
Published: February 2010

AbstractCompatibility, morphology structure, and mechanical properties of CPVC/ABS (Chlorinated polyvinyl chloride/acrylonitrile‐butadiene‐styrene) blends were studied. The core‐shell ratios of ABS were set at 40/60 and 70/30. The interface interactions between ABS and CPVC were changed by modifying the acrylonitrile (AN) content of the shell. The compatibility of CPVC with the shell of ABS was studied by the blends of CPVC/SAN with different AN content in SAN. Dynamic mechanical analysis results of CPVC/SAN were in accordance with the morphological properties of CPVC/ABS. The mechanical properties of CPVC/ABS blends in which the polybutadiene content was set to 15 wt % were studied. Results showed, with the change of AN content, the impact strength followed different way for CPVC/ABS blends with different core‐shell ratios of ABS because of the influence of the compatibility. When the core‐shell ratio was 40/60, the CPVC/ABS blends were much ductile in more widely AN range than the blends, whereas the core‐shell ratio of ABS was 70/30. The differences also showed in the SEM micrographs by the investigation of toughening mechanism. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Effect of 3‐aminopropyltriethoxysilane and N,N‐ dimethyldodecylamine as modifiers of Na+‐montmorillonite on SBR/organoclay nanocomposites
Authors: Kim Wook‐Soo , Yi Juhui , Lee Dong‐Hyun , Kim Il‐Jin , Son Woo‐Jung , Bae Jong‐Woo , Kim Wonho 
Published: February 2010

AbstractIn this study, styrene butadiene rubber (SBR)/organoclay nanocomposites were manufactured using the latex method with 3‐aminopropyltriethoxysilane (APTES) and N,N‐dimethyldodecylamine (DDA) as modifiers. The layer‐to‐layer distance of the silicates was observed according to each manufacturing process for APTES as the modifier using the X‐ray diffraction (XRD) method. From the XRD results and the TEM images, the dispersion of the silicates impoved for both APTES‐MMT and DDA‐MMT, and the dispersion of the silicates with the DDA modifier improved more than the APTES modifier. The SBR/DDA‐MMT compound exhibited the fastest scorch time, optimal vulcanization time, and cure rate. The dynamic viscoelastic properties of the SBR/APTES‐MMT compound were measured according to the change in the strain amplitude in order determine if a covalent bond was formed between APTES and bis(triethoxysilyl‐propyl)tetrasulfide (TESPT). The mechanical properties of the SBR/DDA‐MMT nanocomposite improved more than the SBR/APTES‐MMT composite because the vulcanization effects of alkylamine and the dispersion of silicates within the rubber matrix were relatively good. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Preparation and characterization of PEGylated terlipressin
Authors: Wang Xiufang , Tian Yong , Lin Hansen , Zang Linquan 
Published: February 2010

AbstractTerlipressin was chemically modified by reaction with succinimidyl propionate‐ monomethoxy polyethylene glycol (mPEG‐SPA). To determine the PEGylated degree, the position and the optimized condition for PEGylated terlipressin, the reactions were monitored in different pH value buffers at different molar ratios by reversed‐phase high performance liquid chromatography (RP‐HPLC). Tryptic digestion and matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry (MALDI‐TOF MS) was used. The results showed that the amount of mono‐PEG‐terlipressin was higher at lower pH value and lower content of PEG. Meanwhile, the amount of di‐PEG‐terlipressin was higher at higher pH value and higher content of PEG under the conditions investigated. The position of PEGylated terlipressin was confirmed by tryptic digestion. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Microstructural studies of PMMA impregnated mortars
Authors: Nair Priya , Ku Du Hyun , Lee Chul Woo , Park Hun Young , Song Ha Young , Lee Sang Su , Lee Won Mook 
Published: February 2010

AbstractStudies on cement concrete microstructures are carried out to explain experimentally observed phenomenon and for modeling of concrete at the macroscopic level. In this article, the preparation of polymer impregnated mortar (PIC) is carried out by partially or fully replacing the pores in the cement mortars (OPC) by PMMA. The effect of this polymer impregnation on density and morphology of the cement matrix is studied. The microstructural changes in the mortar, on exposure of these specimens to hydrochloric acid and sea water for 7 and 28 days, are also investigated in this article. The above studies indicated that the polymer addition decreased the voids in the mortar thereby preventing leaching of water soluble salts present in the OPC. It was observed that the polymer also prevented the external chemical media from permeating into the cement matrix and undergoing interactions with it. It is concluded that the durability and chemical resistance properties of the PIC are better compared with OPC. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Toughening of recycled poly(ethylene terephthalate) with clay‐compatibilized rubber phase
Authors: Kelnar Ivan , Sukhanov Valentin , Rotrekl Jakub , Kaprálková Ludmila 
Published: February 2010

AbstractRecycled bottle‐grade PET (rPET) is a valuable low‐cost polymeric material. However, enhancement of its mechanical properties is necessary for many applications. This work is focused on clay‐reinforced/compatibilized rPET/elastomer system. Although the clay addition to various rPET/elastomer blends caused a remarkable refinement of structure, more pronounced for clay with less polar modification, both a gain or decrease in strength and toughness occurred, whereas an increase in modulus was found for all systems. This is a consequence of simultaneous complex affecting many parameters by clay and both antagonistic and synergistic combination of respective effects. Best results were found for low contents of EPR rubber and its preblending with clay. The presented results indicate that a suitable combination of nanosilicates with rubber can lead to rPET materials with fairly enhanced properties. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Design and development of temperature sensitive porous poly(NIPAAm‐AMPS) hydrogels for drug release of doxorubicin‐a cancer chemotherapy drug
Authors: Varaprasad K. , Ravindra S. , Reddy N. Narayana , Vimala K. , Raju K. Mohana 
Published: February 2010

AbstractTemperature sensitive polymer network porous hydrogels were developed with N‐Isopropylacrylamide (NIPAAm) and AMPS (2‐acrylamido‐2‐methyl‐1‐propanesulfonicacid), as well as with sucrose as porogen by crosslinking with hydrophilic crosslinker N,N1‐methylenebisacrylamide (MBA). The temperature responsive behaviour, the swelling/deswelling kinetics of the hydrogels were investigated. The structural and morphological characterizations of the developed hydrogels were obtained from FTIR spectroscopy and scanning electron microscopy (SEM). The increment in the lower critical solution temperature (LCST) of NIPAAm hydrogels can be done with the help of AMPS and it is confirmed with differential scanning calorimetry (DSC) as well as temperature dependent swelling curves. The model cancer chemotherapy drug Doxorubicin (Dox) was loaded into theses hydrogels and the release studies as well as the released profiles of the drug showed that more than 8–54% of the loaded drug was released in the first half‐an‐hour at a buffer solution of 7.4 and the rest of the drug was released slowly. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Bio‐hybrid nanocomposite coatings from sonicated chitosan and nanoclay
Authors: Vartiainen Jari , Tuominen Mikko , Nättinen Kalle 
Published: February 2010

AbstractNanocomposite films and coatings with improved properties were produced from ultrasonic dispersed chitosan and hydrophilic bentonite nanoclay. Bio‐hybrid coatings were applied onto argon–plasma‐activated LDPE coated paper. The intercalation of chitosan in the silicate layers was confirmed by the decrease of diffraction angles as the chitosan/nanoclay ratio increased. Nanocomposite films and multilayer coatings had improved barrier properties against oxygen, water vapor, grease, and UV‐light transmission. Oxygen transmission was significantly reduced under all humidity conditions. In dry conditions, over 99% reduction and at 80% relative humidity almost 75% reduction in oxygen transmission rates was obtained. Hydrophilic chitosan was lacking the capability of preventing water vapor transmission, thus total barrier effect of nanoclay containing films was not more than 15% as compared with pure chitosan. Because to very thin coatings (≤1 μm), nanoclay containing chitosan did not have antimicrobial activity against test strains. All coating raw materials were “generally recognized as safe” (GRAS) and the calculated total migration was in all cases ≤6 mg/dm2, thus the coatings met the requirements set by the packaging legislation. Processing of the developed bio‐hybrid nanocomposite coated materials was safe as the amounts of released particles under rubbing conditions were comparable with the particle concentrations in a normal office environment. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Biodegradable poly(ethylene succinate) blends and copolymers containing minor amounts of poly(butylene succinate)
Authors: Lu Hsin‐Ying , Chen Ming , Chen Chi He , Lu Jin‐Shan , Hoang Kim‐Chi , Tseng Min 
Published: February 2010

AbstractPoly(ethylene succinate) (PES), poly(butylene succinate) (PBS), and PES‐rich copolyesters were synthesized using an effective catalyst, titanium tetraisopropoxide. PES was blended with minor amounts of PBS for the comparison. The compositions of the copolyesters and the blends were determined from NMR spectra. Their thermal properties were studied using a differential scanning calorimeter (DSC), a temperature modulated DSC (TMDSC), and a thermogravimetric analyzer. No significant difference exists among the thermal stabilities of these polyesters and blends. For the blends, the reversible curves of TMDSC showed a distinct glass‐rubber transition temperature (Tg), however, the variation of the Tg values with the blend compositions was small. Isothermal crystallization kinetics and the melting behavior after crystallization were examined using DSC. Wide‐angle X‐ray diffractograms (WAXD) were obtained for the isothermally crystallized specimens. The results of DSC and WAXD indicate that the blends have a higher degree of crystallinity and a higher melting temperature than those of the corresponding copolymers. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Glycan profiling of anti–citrullinated protein antibodies isolated from human serum and synovial fluid
Authors: Scherer Hans U. , van der Woude Diane , Ioan‐Facsinay Andreea , el Bannoudi Hanane , Trouw Leendert A. , Wang Jun , Häupl Thomas , Burmester Gerd‐R. , Deelder André M. , Huizinga Tom W. J. , Wuhrer Manfred , Toes René E. M. 
Published: February 2010

AbstractObjectiveAnti–citrullinated protein antibodies (ACPA) exhibit unique specificity for rheumatoid arthritis. However, it is incompletely understood whether and how ACPA contribute to disease pathogenesis. The Fc part of human IgG carries 2 N‐linked glycan moieties that are crucial for the structural stability of the antibody and that modulate both its binding affinity to Fcγ receptors and its ability to activate complement. We undertook this study to analyze Fc glycosylation of IgG1 ACPA in serum and synovial fluid (SF) in order to further characterize the immune response to citrullinated antigens.MethodsACPA were isolated by affinity purification using cyclic citrullinated peptides as antigen. IgG1 Fc glycosylation was analyzed by mass spectrometry. ACPA IgG1 glycan profiles were compared with glycan profiles of total serum IgG1 obtained from 85 well‐characterized patients. Glycan profiles of paired SF and serum samples were available from 11 additional patients.ResultsCompared with the pool of serum IgG1, ACPA IgG1 lacked terminal sialic acid residues. In SF, ACPA were highly agalactosylated and lacked sialic acid residues, a feature that was not detected for total SF IgG1. Moreover, differential ACPA glycan profiles were detected in rheumatoid factor (RF)–positive and RF‐negative patients.ConclusionACPA IgG1 exhibit a specific Fc‐linked glycan profile that is distinct from that of total serum IgG1. Moreover, Fc glycosylation of ACPA differs markedly between SF and serum. Since Fc glycosylation directly affects the recruitment of Fc‐mediated effector mechanisms, these data could further our understanding of the contribution of ACPA to disease pathogenesis.
A comparison study of some Arabic root finding algorithms
Authors: Al‐Shawakfa Emad , Al‐Badarneh Amer , Shatnawi Safwan , Al‐Rabab'ah Khaleel , Bani‐Ismail Basel 
Published: February 2010

AbstractArabic has a complex structure, which makes it difficult to apply natural language processing (NLP). Much research on Arabic NLP (ANLP) does exist; however, it is not as mature as that of other languages. Finding Arabic roots is an important step toward conducting effective research on most of ANLP applications. The authors have studied and compared six root‐finding algorithms with success rates of over 90%. All algorithms of this study did not use the same testing corpus and/or benchmarking measures. They unified the testing process by implementing their own algorithm descriptions and building a corpus out of 3823 triliteral roots, applying 73 triliteral patterns, and with 18 affixes, producing around 27.6 million words. They tested the algorithms with the generated corpus and have obtained interesting results; they offer to share the corpus freely for benchmarking and ANLP research.
Redesigning of anti‐c‐Met single chain Fv antibody for the cytoplasmic folding and its structural analysis
Authors: Edwardraja Selvakumar , Neelamegam Rameshkumar , Ramadoss Vijayaraj , Venkatesan Subramanian , Lee Sun‐Gu 
Published: February 2010

AbstractTypically, single chain Fv antibodies are unable to fold properly under a reducing cytoplasm because of the reduction of disulfide bonds. The inability to fold limits both the production of the functional scFvs and their targeting against antigens, which are generally executed in a reducing cytoplasm. In this study, the target scFv CDR was grafted with stable human consensus framework sequences, which enabled the generation of a foldable scFv in a reducing cytoplasm of Escherichia coli. Additionally, the structural features affecting the folding efficiency of the engineered scFv were identified by analyzing the predicted structure. An anti‐c‐Met scFv, which was a cytoplasmic non‐foldable protein, was redesigned as the model system. This study confirmed that the engineered anti‐c‐Met scFv was folded into its native form in the cytoplasm of E. coli BL21(DE3) without a significant loss in the specific binding activity against c‐Met antigen. The structures of the wild‐type anti‐c‐Met scFv and the engineered scFv were predicted using homology modeling. A comparative analysis based on the sequence and structure showed that the hydrophobicity of 12 solvent exposed residues decreased, and two newly formed salt bridges might have improved the folding efficiency of the engineered scFv under the reducing condition. Biotechnol. Bioeng. 2010; 106: 367–375. © 2010 Wiley Periodicals, Inc.
Factors promoting emissions of nitrous oxide and nitric oxide from denitrifying sequencing batch reactors operated with methanol and ethanol as electron donors
Authors: Lu Huijie , Chandran Kartik 
Published: February 2010

AbstractThe emissions of nitrous oxide (N2O) and nitric oxide (NO) from biological nitrogen removal (BNR) operations via nitrification and denitrification is gaining increased prominence. While many factors relevant to the operation of denitrifying reactors can influence N2O and NO emissions from them, the role of different organic carbon sources on these emissions has not been systematically addressed or interpreted. The overall goal of this study was to evaluate the impact of three factors, organic carbon limitation, nitrite concentrations, and dissolved oxygen concentrations on gaseous N2O and NO emissions from two sequencing batch reactors (SBRs), operated, respectively, with methanol and ethanol as electron donors. During undisturbed ultimate‐state operation, emissions of both N2O and NO from either reactor were minimal and in the range of <0.2% of influent nitrate‐N load. Subsequently, the two reactors were challenged with transient organic carbon limitation and nitrite pulses, both of which had little impact on N2O or NO emissions for either electron donor. In contrast, transient exposure to oxygen led to increased production of N2O (up to 7.1% of influent nitrate‐N load) from ethanol grown cultures, owing to their higher kinetics and potentially lower susceptibility to oxygen inhibition. A similar increase in N2O production was not observed from methanol grown cultures. These results suggest that for dissolved oxygen, but not for carbon limitation or nitrite exposure, N2O emission from heterotrophic denitrification reactors can vary as a function of the electron donor used. Biotechnol. Bioeng. 2010; 106: 390–398. © 2010 Wiley Periodicals, Inc.
An integrated electrical drive control laboratory: Speed control of induction motors
Authors: Dandil Bes̨ir 
Published: February 2010

AbstractThis paper presents an integrated environment for speed control of vector controlled induction motor (IM) including simulation and experimental study. In the prepared integrated environment, students and researchers can realise the speed control of IM by selecting the classical controllers such as proportional + integral + derivative (PID) and integral + proportional (IP) or intelligent controllers such as fuzzy (FC), neural network (NNC) and neuro‐fuzzy (NFC). Users can perform simulation and experimental studies on‐line to evaluate performance of the control system under parameter and load variations in IM drive. The integrated environment allows users to compare simulation and experimental results and evaluate basic distinctions between classical and intelligent controllers. Furthermore, performance of the controller designed by the user can be tested on‐line. Important variables of drive system can be monitored as graphically or saved as digitally for further processing by using the designed graphical user interface (GUI). © 2010 Wiley Periodicals, Inc. Comput Appl Eng Educ 20: 410–418, 2012
Towards Preparative Scale Steroid Hydroxylation with Cytochrome P450 Monooxygenase CYP106A2
Authors: Zehentgruber Daniela , Hannemann Frank , Bleif Sabrina , Bernhardt Rita , Lütz Stephan 
Published: February 2010

AbstractCytochrome P450 monooxygenases are of outstanding interest for the synthesis of pharmaceuticals and fine chemicals, due to their ability to hydroxylate CH bonds mainly in a stereo‐ and regioselective manner. CYP106A2 from Bacillus megaterium ATCC 13368, one of only a few known bacterial steroid hydroxylases, enables the oxidation of 3‐keto‐4‐ene steroids mainly at position 15. We expressed this enzyme together with the electron‐transfer partners bovine adrenodoxin and adrenodoxin reductase in Escherichia coli. Additionally an enzyme‐coupled cofactor regeneration system was implemented by expressing alcohol dehydrogenase from Lactobacillus brevis. By studying the conversion of progesterone and testosterone, the bottlenecks of these P450‐catalyzed hydroxylations were identified. Substrate transport into the cell and substrate solubility turned out to be crucial for the overall performance. Based on these investigations we developed a new concept for CYP106A2‐catalyzed steroid hydroxylations by which the productivity of progesterone and testosterone conversion could be increased up to 18‐fold to yield an absolute productivity up to 5.5 g L−1 d−1. Product extraction with absorber resins allowed the recovery of quantitative amounts of 15β‐OH‐progesterone and 15β‐OH‐testosterone and also the reuse of the biocatalyst.
Next‐Generation Catalysis for Renewables: Combining Enzymatic with Inorganic Heterogeneous Catalysis for Bulk Chemical Production
Authors: Vennestrøm Peter N. R. , Christensen Claus H. , Pedersen Sven , Grunwaldt Jan‐Dierk , Woodley John M. 
Published: February 2010

AbstractNowadays, production of bulk and commodity chemicals from renewable feedstocks is widely debated and investigated as an alternative to the fossil platform. The conversion of biomass necessitates the development of a new generation of catalysts that enable new kinds of reactions from a different chemical platform under different conditions than those conventionally employed. Indeed, new process and catalyst concepts need to be established. Both enzymatic catalysis (biocatalysis) and heterogeneous inorganic catalysis are likely to play a major role and, potentially, be combined. One type of combination involves one‐pot cascade catalysis with active sites from bio‐ and inorganic catalysts. In this article the emphasis is placed specifically on oxidase systems involving the coproduction of hydrogen peroxide, which can be used to create new in situ collaborative oxidation reactions for bulk chemical production.