bluuebunny/crossref_metadata_2025 huggingface dataset:
Isolated Double-Chambered Right Ventricle: A Rare Congenital Heart Disease
Authors: Bezza Sofia , Rhoujjati Mohamed Imad , Eljamili Mohammed , Karimi Saloua El , Elhattaoui Mustapha
Published: January 2024

Double-chambered right ventricle (DCRV) is an uncommon congenital heart condition characterized by a progressive obstruction in the right ventricular outflow tract. This obstruction is caused by anomalous muscles or fibrous tissues that divide the right ventricle into two cavities: a proximal high-pressure chamber (anatomically lower) and a distal low-pressure chamber (anatomically higher). We present a case of a middle-aged man with a medical history of recurrent symptomatic dyspnea. Upon presentation, there were no signs of congestive cardiac failure. The diagnosis was confirmed using transthoracic two-dimensional (2-D) echocardiography and Transesophageal echocardiography (TEE) for more precise characterization. The primary objective of this case report is to highlight the rarity of this congenital heart disease, particularly in adults.
Processing Practices and Quality of Dairy Products in Burkina Faso
Authors: Bayili Geoffroy Romaric , Millogo Kalo Marcus , Dossou Philips , Bengaly Leila Portio Ardiata , Ouangraoua Abigail Naomi , Guel Salif , Coulibaly-Diakité Mariam
Published: January 2024

Dairy industry is playing an increasing role in food security and economics of West African countries. However there is a need for more information on the quality and history of the dairy products found on the local markets in order to guide necessary reformations in this sector. The objective of this study was to provide data on the quality and processing practices of dairy products, including some locally manufactured dairy products and imported powder milk commercialised in Burkina Faso. Specifically, a survey was carried out first, to identify the locally manufactured dairy products as well as the manufacturing practices, particularly the malpractices not yet reported in the literature. Then, locally manufactured dairy products (excluding the traditionally fermented milk lait caillé and pasteurised milk), imported powder milk from brands frequently used for processing milk products and fraudulent practices identified during the survey were evaluated through laboratory analyses. Physico-chemical parameters such as pH, acidity and moisture content were determined. In addition microbiological parameters such as aerobic mesophilic flora, yeast and mold, thermotolerant coliforms or enterobactria, were also determined. 

Results from the survey showed that good manufacturing practices were not strictly observed. In addition it was reported use of salt and a popular street medicine “toupaϊ” (supposedly an antibiotic) for delaying the spoilage/fermentation of the raw milk. Six types of locally manufactured milk products were identified while seven brands of powder milk were frequently used, after repackaging, for processing milk products. Most samples of locally manufactured products were unsatisfactory for fungal and thermotolerant coliforms loads. Powder milk samples showed absence of enterobacteria. Sensory analyses showed that locally manufactured products from powder milk were more appreciated than those made from raw milk. Attempts to reproduce the malpractices of using salt or “toupaϊ” did not lead to significant results compared to the control, suggesting that some respondents did not fully open up about the malpractices. These data are useful since they would give tools to policy makers for quality control and regulation in the sector of dairy products.
Effects of Herbicides and Nano Urea Mixture on Weeds, Yield Attributes and Yield of Wheat (Triticum aestivum)
Authors: Asif Mo , Poonia Todar Mal , Hooda Virender Singh , Pradhan Dharani Dhar , Bhavesh
Published: January 2024

Wheat (Triticum aestivum) is second most important staple crop in India after rice. Weeds have emerged as the major biotic stress in wheat. Post-emergence herbicidal combinations are used widely to control the complex weed flora in wheat crops. A field experiment was carried out to study the “Effects of herbicides and nano urea mixture on weeds, yield attributes and yield of wheat (Triticum aestivum)”. The experiment was performed in randomized blocked design with three replications and fourteen treatments in Rabi season 2022-23 at Agronomy Research Farm, CCS Haryana Agricultural University, Hisar. Significantly minimum weed count (1.52 m-2) and dry weight (1.49 g m-2) and maximum weed control efficiency (88.6%) of Phalaris minor and broadleaved weeds (87%) was recorded with application of clodinafop + metribuzin 60 + 210 g ha-1 with nano urea 3 ml L-1 followed by clodinafop + metribuzin 60 + 210 g ha-1 at 90 DAS. In case of yield attributes i.e. number of effective tillers per meter row length (92.5), spike length (11.4 cm), number of grains spike-1 (55.9) and 1000-grain weight (43.8) were higher with application of clodinafop + metribuzin 60 + 210 g ha-1 with nano urea 3 ml L-1 followed by clodinafop + metribuzin 60 + 210 g ha-1. Grain yield (5876 kg ha-1) and B:C (1.94) was recorded higher with application of clodinafop + metribuzin 60 + 210 g ha-1 with nano urea 3 ml L-1 followed by clodinafop + metribuzin 60 + 210 g ha-1 which was significantly higher than weedy check but at par with the weed free treatment.
Comparative Effect of Subhash Palekar’s Natural Farming, Organic and Inorganic Systems of Nutrition on Performance of Fodder Sorghum and Pearl Millet Hybrids
Authors: Kumari Priyanka , Kumar Naveen
Published: January 2024

Aims: To evaluate different nutrient management practices in fodder sorghum and pearl millet hybrids.

Study Design:  Randomized block design.

Place and Duration of Study: A field experiment was conducted at the research farm of Fodder Section, CSK HPKV, Palampur during Kharif seasons of 2018 and 2019

Methodology: Ten nutrient management practices i.e. absolute control (T1), 5% Jeevamrit (T2), 10% Jeevamrit (T3), seed treatment with Beejamrit + 5% Jeevamrit (T4), seed treatment with Beejamrit + 10% Jeevamrit (T5), 10 t/ha FYM + 5% Jeevamrit (T6), 10 t/ha FYM + 10% Jeevamrit (T7), 50% recommended N + 10 t/ha FYM + 5% Jeevamrit (T8), 50% recommended N + 10 t/ha FYM + 10% Jeevamrit (T9) and recommended NPK through inorganic sources (T10) were tested in randomized block design with three replications.

Results: The results indicated that integrated nutrient management i.e. 50 per cent recommended N + 10 t/ha FYM + 10% Jeevamrit and 50 per cent recommended N + 10 t/ha FYM + 5% Jeevamrit and recommended NPK through inorganic sources remaining at par resulted in better crop growth (plant height, shoot number, leaf stem ratio, percent proportion), higher fodder yield (green and dry fodder yields), NPK uptake and crude protein yield than rest of the organic (10 t/ha FYM + 10% Jeevamrit and 10 t/ha FYM + 5% Jeevamrit) and natural farming (Beejamrit + 5% Jeevamrit and Beejamrit + 10% Jeevamrit) nutrient management treatments. Application of recommended NPK resulted in highest net returns (79049 INR/ha) and net returns per rupee invested (2.09).

Conclusion: Integrated and inorganic nutrient management practices in fodder sorghum and pearl millet hybrids appeared best practices for realising higher yield than organic and natural farming nutrient management practices.
Effect of PGR and Chemicals on Shelf Life, Bunch and Berry Quality Parameters of Sudhakar Seedless Grapes (Vitis vinifera L.)
Authors: Bhagwat S. R. , Kalbhor J. N. , Gavali A. H.
Published: January 2024

The experiment was conducted on Sudhakar Seedless vines grafted on 110-R rootstock were selected for this study. The experiment was designed in randomized block design (RBD) having five treatments with four replications were carried out at MRDBS Nashik during 2020-2021. Pre-harvest application of treatments (Chitosan at 10 ppm, Naphthalene acetic acid at 100 ppm, activated Potassium salt @ 2.0 g/ liter, Salicylic acid at 2.0 ml/liter and Potassium Schoenite @ 2.0 g/liter along with untreated vines were applied at veraison stage of berry development. Application of Chitosan @ 10 ppm resulted in to the increase berry size and berry quality along with less Number of rotten berries in physiological loss in weight. Followed by the application of Naphthalene acetic acid at 100 ppm recorded less Number of rotten in this study. However, the lowest physiological loss of weight (%) were recorded with the application of Naphthalene acetic acid. The increasing dose of Naphthalene acetic acid resulted into decrease in pre- harvest berry drop. In grapevines, Application of salicylic acid significantly increase in berry weight, bunch weight, Total Soluble Solids /acidity ratio as compare to untreated vines. Biochemical composition of berries was influenced by the application of Activated potassium salt at different concentration. The application of Potassium schoenite in grapevines were found effective for increasing TSS of Sudhakar seedless grapes.
Recursive least‐squares and accelerated convergence in stochastic approximation schemes
Authors: Ljung Lennart
Published: August 2002

The so‐called accelerated convergence is an ingenuous idea to improve the asymptotic accuracy in stochastic approximation (gradient based) algorithms. The estimates obtained from the basic algorithm are subjected to a second round of averaging, which leads to optimal accuracy for estimates of time‐invariant parameters. In this contribution, some simple calculations are used to get some intuitive insight into these mechanisms. Of particular interest is to investigate the properties of accelerated convergence schemes in tracking situations. It is shown that a second round of averaging leads to the recursive least‐squares algorithm with a forgetting factor. This also means that in case the true parameters are changing as a random walk, accelerated convergence does not, typically, give optimal tracking properties. Copyright © 2001 John Wiley & Sons, Ltd.
Identification and adaptive control of some stochastic distributed parameter systems
Authors: Pasik‐Duncan B.
Published: August 2002

An important class of controlled linear stochastic distributed parameter systems is that with boundary or point control. A survey of some existing adaptive control problems with their solutions for the boundary or the point control of a partially known linear stochastic distributed parameter systems is presented. The distributed parameter system is described by an analytic semigroup with cylindrical white noise and a control that occurs only on the boundary or at discrete points. The unknown parameters in the model appear affinely in both the infinitesimal generator of the semigroup and the linear transformation of the control. The noise in the system is a cylindrical white Gaussian noise. Strong consistency is verified for a family of least‐squares estimates of the unknown parameters. For a quadratic cost functional of the state and the control, the certainty equivalence control is self‐optimizing, that is the family of average costs converges to the optimal ergodic cost. Copyright © 2001 John Wiley & Sons, Ltd.
Fetal hemoglobin elevation in Hb lepore heterozygotes and its correlation with β globin cluster linked determinants
Authors: Gonçalves Isabel , Henriques Ana , Raimundo Ana , Picanço Isabel , Reis Ana , Correia Jr. Esmeraldina , Santos Ester , Nogueira Paulo , Osório‐Almeida Leonor
Published: August 2002

We have analysed, at the hematological and molecular level, 51 Hb lepore heterozygotes and three compound heterozygotes for Hb Lepore and HbS (HbLep/HbS) in 26 unselected Portuguese families. The Lepore Boston variant was present in one family, in association with classical haplotype V. All of the other Lepore alleles present haplotype III in association with XmnI (+)5′ of Gγ gene, in tight linkage disequilibrium to the major mutation found in the Portuguese population, the Lepore Baltimore variant ( δ68Leu‐β84Thr). The three compound heterozygotes are the first HbLep/HbS individuals reported in the literature, with the Lepore Baltimore mutation linked to haplotype III. In agreement with other studies, these Lepore Baltimore heterozygotes have higher HbF (1.4–14.1% of total hemoglobin) than published cases of Lepore Boston (0.8–5.4%), which is associated with XmnI(–). Among the Lepore Baltimore heterozygotes, the (AT)xTy repeat region at –540 bp of the β globin gene in trans to the Lepore chromosome, can account for much of the variability in HbF level. The allele (AT)7T7 is associated with lower HbF, and (AT)9T5 is associated with higher HbF. As we previously reported for β thalassemic carriers, we observe in Lepore Baltimore carriers an effector in trans, linked to the (AT)xTy sequence, acting as an HPFH (Hereditary Persistence of Fetal Hemoglobin) determinant. Am. J. Hematol. 69:95–102, 2002. © 2002 Wiley‐Liss, Inc.
Expression and sequence analyses of p33ING1 gene in myeloid leukemia
Authors: Ito K. , Kinjo K. , Nakazato T. , Ikeda Y. , Kizaki M.
Published: August 2002

p33ING1 is a novel candidate tumor suppressor gene which is involved in the regulation of apoptosis. p33ING1 interacts with p53 signaling pathway and regulates cellular growth. It has reported that the expression of p33ING1 mRNA was decreased in lymphoid malignancies. We thus investigated the potential involvement of p33ING1 abnormalities in myeloid leukemias. However, the levels of p33ING1 transcript were almost equal in 3 AML cell lines and 10 fresh AML samples. In addition, neither point mutations nor deletions in p33ING1 gene were found in myeloid leukemias. These results suggest that p33ING1 may not be a major candidate tumor suppressor gene in myeloid leukemias. Am. J. Hematol. 69:141–143, 2002. © 2002 Wiley‐Liss, Inc.
Gelatinous transformation of bone marrow from a starch‐free diet
Authors: Wang Chen , Amato Dominick , Fernandes Bernard
Published: August 2002

Gelatinous marrow transformation is characterized by marrow hypoplasia, fat atrophy, and gelatinous material deposition, and usually develops as a hematologic complication of chronic wasting disorders. Most of the cases associated with severe nutritional deficiency were seen in anorexia nervosa due to a depletion of protein or fat. This report describes a case of gelatinous transformation attributed to a specific restriction of carbohydrates in diet. The hematologic deficiency was eventually recovered after the patient resumed a regular starch‐containing diet. This brief report illustrates the potential side effect of the compulsive dietary behavior on the hematologic system. Am. J. Hematol. 68:58–59, 2001. © 2001 Wiley‐Liss, Inc.
Psychopathology, GABA, and the Rubinstein‐Taybi syndrome: A review and case study
Authors: Hellings Jessica A. , Hossain Shaheena , Martin Judy K. , Baratang Ramil R.
Published: August 2002

An adult female with congenital Rubinstein‐Taybi syndrome (RTS) and severe mental retardation is described, who presented with symptoms of severe over‐activity, short attention span, mood lability, and aggressive outbursts in a cyclical pattern, suggestive of recurrent manic‐like episodes. These symptoms improved significantly with divalproex (Depakote) monotherapy. Review of the existing studies showed that 10–76% of persons with RTS may be identified with similar behavioral symptoms. We postulate other persons with RTS may respond to divalproex, and there may be some relationship between the chromosome 16p13.3 deletion and γ‐aminobutyric acid (GABA) receptor or neurotransmitter abnormalities. Recent molecular genetic studies suggest a linkage of this region to bipolar mood disorder and autism, both of which were diagnosed in this patient. Further prospective study is needed of RTS persons regarding behavioral problems, comorbid psychiatric diagnoses, and treatment responses, correlated with genetic abnormalities. © 2002 Wiley‐Liss, Inc.
Delineation of the dup5q phenotype by molecular cytogenetic analysis in a patient with dup5q/del 5p (cri du chat)
Authors: Levy Brynn , Dunn Teresa M. , Kern Jeffrey H. , Hirschhorn Kurt , Kardon Nataline B.
Published: August 2002

An infant girl presented with multiple congenital abnormalities and a distinctive mewing cry. Her karyotype was 46,XX,add5p. Chromosome analysis on the mother revealed an apparently balanced pericentric inversion of chromosome 5, with the precise position of the breakpoints not clearly discernable by GTG banding, 46,XX,inv(5)(p15.2/3?q35.1?). Fluorescence in situ hybridization (FISH) studies using a commercial cri du chat probe (D5S721,D5S23) revealed signals on both the normal and derivative chromosomes. Telomeric probes specific for 5p and 5q were used to confirm the pericentric inversion in the mother and demonstrated the loss of the terminal 5p region and a duplication of the terminal 5q region in the proband. The imbalance on chromosome 5 in the patient was further defined using comparative genomic hybridization (CGH), which revealed a loss of material from 5p15.3 → pter and a gain of 5q34 → qter. The presence of the cat‐like cry appears to be the only specific feature that can be linked to the loss of 5p material. The remaining dysmorphic features of this infant appear to be due specifically to the duplication of the 5q sequences. The combination of FISH, CGH, and cytogenetics has confirmed that the characteristic cry of the cri du chat syndrome is due to the deletion of the most distal part of the classic del 5p region. More importantly, our investigation has defined the duplication of 5q34 → qter as a distinct clinical phenotype. © 2002 Wiley‐Liss, Inc.
Affected sibling pair linkage analysis of qualitative and quantitative traits for schizophrenia on chromosome 22 in a Chinese population
Authors: Cai Guiqing , Li Tao , Deng Hong , Zhao Jinghua , Hu Xun , Murray Robin M. , Liu Xiehe , Sham Pak C. , Collier David A.
Published: August 2002

We performed nonparametric linkage analysis on 136 families with two or more siblings with schizophrenia from Sichuan, southwestern China. In addition to categorical diagnosis, we used quantitative trait information from the Positive and Negative Symptom Scale and the modified Overt Aggression Scale. Categorical analysis using the diagnosis of schizophrenia and a maximum likelihood identity‐by‐descent method produced scores of close to 0 throughout the whole region tested. Multipoint analysis allowed exclusion of most markers with a relative risk of > 2, but did not exclude the possibility of a relative risk of < 1.5 for four of the markers. Our results provide no significant evidence for a locus for schizophrenia on chromosome 22. Quantitative linkage analysis using the PANSS‐G scale score produced a maximum LOD score of ∼ 1.2 with the marker D22S310, using either the Haseman‐Elston method or maximum likelihood variance estimation with or without dominance. PANSS‐N produced a maximum LOD score of 1.2 at the D22S283 locus. LOD score of about 1 are easily produced by chance. Thus, we conclude that under quantitative trait we also find no evidence of linkage between schizophrenia and markers on chromosome 22 in our Chinese sibling pair sample. © 2001 Wiley‐Liss, Inc.
Variation in circulating and excreted estradiol associated with testicular activity in male marmosets
Authors: Nunes Scott , Brown Corrine , French Jeffrey A.
Published: August 2002

Concentrations of estradiol (E2) are high in the urine of male marmosets, and links between E2 and paternal behavior have been proposed in black tufted‐ear marmosets, Callithrix kuhlii. However, it is not clear whether urinary E2 in male marmosets: 1) represents production of E2 associated with testicular activity, 2) is associated with adrenal steroid production, or 3) merely reflects peripheral conversion of T to E2 prior to excretion. We tested the hypothesis that urinary E2 in male marmosets represents estrogen production‐associated activity in the hypothalamus‐pituitary‐gonad (HPG) axis. We treated adult male marmosets with gonadotropin‐releasing hormone (GnRH), and used saline‐treated males as controls. We collected blood and urine samples from males before and after treatment, and assayed them for testosterone (T), estradiol (E2), and cortisol (CORT). Treatment with GnRH increased circulating T and E2, and prevented decreases in levels of urinary T and E2. Moreover, changes in plasma and urinary E2 after treatment were positively correlated with post‐treatment changes in T. Thus, our data are consistent with both plasma and urinary E2 in male marmosets increasing as a result of testicular stimulation. However, treatment with GnRH did not affect plasma or urinary CORT concentrations of males, suggesting that the E2 excreted by males is not of adrenal origin. We also compared urinary T, E2, and CORT levels between intact and castrated male common marmosets (Callithrix jacchus). Urinary concentrations of T and E2, but not CORT, were significantly lower in castrated than in intact males, further suggesting that E2 in male marmosets varies with testicular activity. Am. J. Primatol. 56:27–42, 2002. © 2002 Wiley‐Liss, Inc.
Hominid cranium from Omo: Description and taxonomy of Omo‐323‐1976‐896
Authors: Alemseged Zeresenay , Coppens Yves , Geraads Denis
Published: August 2002

Omo‐323‐1976‐896, a partial hominid cranium dated to ca. 2.1 from the Member G, Unit G‐8 of the Shungura Formation, lower Omo Basin of Ethiopia, is described. It is suggested that the specimen is an adult male based on the well‐developed and completely fused sagittal crest; heavily worn teeth; relatively large canine; and size of the articular eminence. Omo‐323 consists of fragments of the frontal, both temporals, occipital, parietals, and the right maxilla, and is attributed to Australopithecus boisei, making it the oldest known cranium of this species. The specimen shares features with Australopithecus aethiopicus (KNM‐WT 17000), thus supporting the existence of an evolving East African robust lineage between ca. 2.6–1.2 Ma. The morphology of Omo‐323 increases our knowledge of the intraspecific variability of A.boisei. Am J Phys Anthropol 117:103–112, 2002. © 2002 Wiley‐Liss, Inc.
Genetic basis of human female pelvic morphology: A twin study
Authors: Sharma Krishan
Published: August 2002

To examine the relative role of genetic and environmental factors on pelvic morphology, data on 60 pairs of female twins (30 monozygotic (MZ) and 30 dizygotic (DZ)) were analyzed. Fourteen pelvic measurements were normally distributed, and two were not. Association of twin type with the mean value of a trait was found in only 1 out of 8 traits. Heterogeneity of variance between zygosities was observed in 4 pelvic traits (50%), invalidating within‐pair estimates of genetic variance for these traits. Evidence of stronger environmental covariance for MZ than DZ twins was observed for only one trait (sitting height iliocristale). A significant genetic component of variation was observed for age at menarche and in the pelvic area. In instances where inequality of variances between zygosities was demonstrated, total among‐pair and within‐pair mean squares were larger for dizygotic than for monozygotic twins. This is interpreted as evidence of greater environmental influence between zygosities. Environmental modification was not of the same magnitude in various pelvic traits. Bitrochanteric breadth had the highest magnitude of cultural heritability, indicating that cultural factors played an important role in determining hip breadth. Am J Phys Anthropol 117:327–333, 2002. © 2002 Wiley‐Liss, Inc.
Ionic interactions and transport mechanism in polyurethane electrolytes
Authors: Fang Bin , Wang Xinling , Tang Xiaozhen , Zhu Pinfang
Published: August 2002

Alternating current (AC) impedance, Fourier transform (FT)–Raman, and Fourier transform infrared (FTIR) have been conducted on solutions of poly(ethylene oxide)(MW=1000)–urethane electrolytes commingled with LiCF3SO3 as the function of temperature and salt concentration. From the analysis of the Vs(SO3) vibration, the ionic concentration of salt in various chemical environments can be calculated approximately. The spectroscopic evidence was found for the redissociated ion pairs, and ionic congeries increased with increasing temperature. AC impedance measurements is used to calculate the ionic diffusion coefficient (Di). Investigated the various concentrations (from O/Li = 4 ∼ 20) at the different temperature (40 ∼ 120°C), We found that the calculated values (Di) with the Nernst–Einstein equation are higher than the direct measurement. The discrepancy increases with the increase of temperature. A good correlation between the conductivity and the ionic redissociation is determined from the Vs(SO3) vibration band. The fraction of the “free” ion significantly corresponds to the revised Nernst–Einstein equation by using the Nernst–Einstein relation and compared with those direct measurement. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 785–790, 2002
Elongation flow studies of DNA as a function of temperature
Authors: Sasaki N. , Maki Y. , Nakata M.
Published: August 2002

The response of T4‐phage DNA molecules to an elongational flow field was monitored by flow‐induced birefringence as a function of temperature. The flow‐induced birefringence observed in this study was localized in the pure elongational flow area with a critical strain rate, indicating that the birefringence was attributed to a coil–stretch transition of DNA molecules. The slight decrease in the birefringence intensity with increases in temperature to 40°C was explained by a thermal‐activation process. At temperatures above 50°C, flow‐induced birefringence decreased remarkably, and no birefringence was observed at temperatures above 60°C. After the flow experiments, ambient temperature was reduced back to room temperature, and flow experiments at room temperature were performed again. Flow‐induced birefringence was recovered almost completely in samples for which the first flow measurements were made at temperatures below 53°C. Irreversible changes were observed for samples for which the first flow experiments were performed at temperatures above 55°C. The temperature dependence of UV‐absorption spectra revealed that the double‐strand DNA helix began to partially untwine at a temperature over 50°C, and duplexes became almost completely untwined at a temperature over 55°C. A comparison of electrophoresis patterns for untwined molecules showed that flow‐induced scission of DNA molecules occurred in a sample solution in flow experiments performed at 65°C, while no molecular weight reduction was observed in the sample solution at 55°C. In this article, this difference between the untwined DNA molecules is discussed on the basis of the thermally activated bond scission (TABS) model. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 1357–1365, 2002
Pervaporation of volatile organic compounds/water mixtures through poly(1H,1H,9H‐hexadecafluorononyl methacrylate)‐filled poly(1‐trimethylsilyl‐1‐propyne) membranes
Authors: Mishima S. , Nakagawa T.
Published: August 2002

Poly(1‐trimethylsilyl‐1‐propyne) (PMSP) is a glassy polymer that contains many microvoids. The permselectivity of the PMSP membrane is controlled by the microvoids, and its permeation behavior is different from rubbery polymer membranes. PMSP membrane was filled with poly(1H,1H,9H‐hexadecafluorononyl methacrylate) (PHDFNMA), and the solution‐diffusion mechanism during pervaporation was investigated. Separation performance was increased due to the introduced hydrophobic polymer, PHDFNMA, as compared to the PMSP membrane. For the 62 wt % PHDFNMA‐filled PMSP membrane, the permselectivity was significantly enhanced. The microvoids in the PMSP membrane play an important role in permselectivity. As the feed of ethyl butanoate (EBU) concentration increased and the EBU quantity sorbed into the PHDFNMA‐filled PMSP membrane increased, the diffusion of water was prevented; in turn, the water flux decreased. At a low feed concentration, the diffusivity of the EBU molecule was much lower than that of water due to the larger molecular size of EBU. As EBU was sufficiently sorbed into the membrane, the diffusion of water was prevented by the EBU molecules; in turn, the permselectivity of EBU significantly increased. At a high‐feed EBU concentration, the diffusion of water increased, and the diffusion of EBU decreased to a constant as the PHDFNMA‐filled PMSP membrane was plasticized. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 1054–1060, 2002
Structure and physical properties of cellulose acetate/poly(butylene succinate) blends containing a transition metal alkoxide
Authors: Uesaka Takahiro , Ogata Nobuo , Nakane Koji , Shimizu Katsuji , Ogihara Takashi
Published: August 2002

Two biodegradable polymers, that is, poly(butylene succinate) (BN) and cellulose acetate (CA), were solvent‐cast blended with chloroform. Homogeneous films were obtained from the blend by the addition of tetraisopropyl titanate (TP) as a compatibilizer. We measured the viscosity of the blend solution to investigate the function of TP during the blending process. From the measurement, we conclude that there are interactions among TP, BN, and CA. From optical observation and thermal measurements of the blend films, we found that the structure of blends is in a pseudostable state and that the addition of TP makes the structure units small. From thermogravimetric analyses, we found that the addition of TP decreases the thermal decomposition temperature of the BN/CA blends. From the measurements of mechanical properties of the blends, we found that changing the blend ratio can produce the materials with a wide range of mechanical properties. The hydrolysis of the blends was investigated. The molecular scission of BN/CA blends takes place uniformly not only from the outside but also from the inside of the films. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 1750–1758, 2002
Reactions of hydroxymethyl derivatives of uric acid with oxiranes. II. An analysis of reaction course and product structure
Authors: Cisek‐Cicirko Irmina , Lubczak Jacek
Published: August 2002

Polyetherols containing thermostable purine rings are obtained in reactions of hydroxymethyl derivatives of uric acid with an excess of ethylene oxide or propylene oxide. By using elementary analytical tools and 1H‐NMR spectroscopy, it was possible to follow the course of reaction at various molar ratios of reagents. A migration of formaldehyde molecules from N‐hydroxymethyl groups or from oligooxymethylene bridges to the end of oxyalkyl chains was observed. At the same time, the O‐hydroxymethyl groups are successively blocked by oxiranes. The most probable structure of polyetherols is proposed. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 1955–1962, 2002
Grafting of polystyrene branches to polyethylene and polypropylene
Authors: Park Eun‐Soo , Jin Hyoung‐Joon , Lee Ik‐Mo , Kim Mal‐Nam , Lee Han Sup , Yoon Jin‐San
Published: August 2002

Polyethylene (PE) and polypropylene (PP) were reacted with benzoyl peroxide (BPO) and 2,2,6,6‐tetramethyl‐1‐piperidinyloxy (TEMPO) to prepare PE‐TEMPO and PP‐TEMPO macroinitiators, respectively. Molecular weight of PP decreased, whereas that of PE increased during the reaction with the BPO/TEMPO system. Polystyrene (PS) branches were grafted to PE and PP backbone chains as a result of bulk polymerization of styrene with the PE‐TEMPO and PP‐TEMPO macroinitiators. A significant amount of PS homopolymer was produced as a byproduct. Weight of the resulting PE‐g‐PS and PP‐g‐PS increased with the polymerization time up to 20 h and then leveled off. Melting point of PE and PP domains in PE‐g‐PS and PP‐g‐PS, respectively, lowered as the content of PS in the copolymers increased. However, glass transition of the copolymers was almost identical with that of PS homopolymer, indicating that the constituents in the copolymers were all phase‐separated from each other. In scanning electron microscopy of the incompatible PE/PS, PP/PS, and PE/PP/PS compounded with PE‐g‐PS and PP‐g‐PS, any clear indication of enhanced adhesion between the phases was not observed. However, phase domains in the blends were, nevertheless, reduced significantly to raise mechanical properties such as maximum stress and elongation at break by 20–75%. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 1103–1111, 2002
Melting‐reactive dyes for mass coloration of nylon based on blend compatibilization: Perylene‐3,4,9,10‐tetracarboxylic acid dianhydride
Authors: Meng Qinghua , Huang Deyin , Chen Lin , Wei Shaohua
Published: August 2002

The mass coloration of nylon‐1010 with a melting‐reactive dye, an economically favorable and environmentally friendly method of coloration, is described. Perylene‐3,4,9,10‐tetracarboxylic acid dianhydride (PTAD) was used as a melting‐reactive dye for nylon‐1010, and it showed high thermal stability. A chain‐extending reaction was confirmed by an ultraviolet–visible spectroscopic analysis. The effect of the proportion of added PTAD on the intrinsic viscosity of the polymer was studied, and increased amounts resulted in increased intrinsic viscosity. The light fastness of the colored fibers was found to be 4. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 2164–2167, 2002
Study of the processing chemistry of polyimides with thermogravimetry/Fourier transform infrared/mass spectrometry techniques
Authors: Xie Wei , Heltsley Rebecca , Li Han‐Xu , Lee Charles , Pan Wei‐Ping
Published: August 2002

One of the fundamental aspects of the carbon fiber‐reinforced, high‐temperature polyimide composite AFR700B/T650‐35, namely, the curing chemistry involved in the polyimide formation, was studied in real time with thermogravimetry/Fourier transform infrared (FTIR)/mass spectrometry (MS) evolved‐gas analysis techniques. The off‐gas reaction products identified by FTIR and MS essentially confirmed the literature polyimide curing mechanisms. However, the FTIR/MS data obtained could also accommodate a reversed curing chemistry in which the elimination of water from amide ester formation occurred first and was followed by the release of methanol from subsequent imidization. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 2213–2224, 2002
Study of polyurethane/sulfonated dimethyl fumarate complex
Authors: Zhu Weihua , Tian Liying , Ren Tianbin , Wang Xinling , Tang Xiaozhen , Li Gang
Published: August 2002

In this study linear polyether polyurethanes (PU) and sulfonated dimethyl fumarate (SDMF) were successfully synthesized and a series of novel solid polymer electrolytes, based on the complexes of PU and SDMF, were prepared. Fourier transform–Raman spectroscopy (FT‐Raman), 1H‐NMR, differential scanning calorimetry (DSC), atomic force microscopy (AFM), and complex impedance analysis were utilized to investigate the chemical structure, microscale morphology, and ionic conductive property of this system. Results show that the ionic conductivity of the PU/SDMF series increases with increasing temperature. In the salt concentration range investigated, there is a maximum ionic conductivity for the PU/SDMF system. When the molar ratio of the ether oxygen and sodium cation is about 24, the optimum compatibility between the hard and soft segments is realized and the highest soft‐segment Tg is reached. A further increase in salt concentration causes the aggregation and precipitation of SDMF, and the decrease of the soft‐segment Tg. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 67–74, 2002; DOI 10.1002/app.10205
Photografting of methacrylic acid on polyethylene film: Effect of mixed solvents consisting of water and organic solvent
Authors: Irwan Ginting Suka , Kuroda Shin‐Ichi , Kubota Hitoshi , Kondo Takashi
Published: August 2002

Photografting of methacrylic acid (MAA) on linear low‐density polyethylene film (thickness = 30 μm) was investigated at 60°C in mixed solvents consisting of water and organic solvent with xanthone as the photoiniator. The organic solvents examined were acetone, methanol, tetrahydrofuran, and dioxane. A maximum percentage of grafting was observed at a certain concentration of organic solvent in the mixed solvent, depending on the nature of the organic solvent. Distribution of the grafted chains in the resultant MAA‐grafted film, which was examined by scanning electron microscopy and attenuated total‐reflection IR spectroscopy, was largely influenced by the use of the mixed solvent. The grafted samples swelled in the alkaline region and shrank in acidic medium, showing a pH‐responsive character. The extent of the pH‐responsive function was closely related to the location of grafted chains, which could be controlled by proper choice of the composition of organic solvent in the mixed solvent. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 2454–2461, 2002
Electrochemical synthesis of poly[2‐hydroxyethylmethacrylate] hydrogel: Kinetics and mechanism
Authors: Prashantha K. , Vasanta K. , Pai Kumar , Sherigara B. S.
Published: August 2002

2‐Hydroxyethylmethacrylate (HEMA) was polymerized in an aqueous sulfuric acid–N,N‐dimethylformamide (DMF) medium in a divided cell by an electrolytically generated mediator species titanium(III). Titanium(III)–hydroxylamine sulfate was used as the initiator redox system. The reaction was confined to the cathode compartment and was found to proceed via a free radical mechanism. Kinetics of polymerization were investigated for variation in initial monomer concentrations, acid concentrations, electrical currents, dielectric constants of the solvent medium, and electrode materials. Chain termination of the polymer was due to coupling of growing macroradicals; also, a fraction of the termination took place by a chain transfer mechanism involving the organic solvent molecules. A suitable mechanism for titanium(III)–hydroxylamine sulfate mediated indirect electropolymerization of HEMA has been proposed. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 983–992, 2002; DOI 10.1002/app.10299
Distribution and diffusion coefficients of NaCl in polyamide (nylon‐6,6 and polyxylyleneadipamide) membranes
Authors: Ohya H. , Semenova S. , Mizoguchi K. , Ogihara J. , Fukaya S. , Suzuki Y. , Aihara M. , Negishi Y.
Published: August 2002

Thin membranes of an aliphatic polyamide (nylon‐6,6) and an aromatic polyamide (polyxylyleneadipamide) (PXAP) were prepared, and their distribution (K) and overall diffusion (D) coefficients of sodium chloride were measured with the unsteady‐state and steady‐state dialysis method. The overall diffusion coefficients at a zero concentration [D(0)] of sodium chloride for nylon‐6,6 and PXAP were 1.3–0.8 μm2/s (from 2 min of interfacial polymerization to 4 min) and 0.078, respectively. D(0) for PXAP was about 3 times greater than that of a cellulose acetate (CA) membrane (0.024 μm2/s). The K values for nylon‐6,6 and PXAP were 0.7–0.5 from 2 to 4 min and 0.05, respectively. K for PXAP was almost the same as K for CA (0.06). A two‐part (dense and porous) model of the membrane structure was applied to obtain Dd (the diffusion coefficient in the dense part of the membrane) and Dp (the diffusion coefficient in the porous part of the membrane) for CA, PXAP, and nylon‐6,6 thin membranes. The values of Dd were almost the same for both nylon‐6,6 and PXAP (0.05–0.061 μm2/s) and about 10 times greater than the value for the CA membrane (5.6 × 10−3 μm2/s). Dp for PXAP was almost the same as Dp for CA. However, Dp for the nylon‐6,6 membrane was 10–16 times greater than Dp for the PXAP membrane. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 2605–2612, 2002
Polypropylene–intumescent flame‐retardant composites based on meleated polypropylene as a coupling agent
Authors: Ma Zhi‐Ling , Gao Jun‐Gang , Niu Hai‐Jun , Ding Hai‐Tao , Zhang Jie
Published: August 2002

The phosphoric acid‐pentaerythritol‐melamine copolymer, which is composed of three main components of intumescent flame retardant (IFR) and has optimal intumescent degree, was selected as IFR. The influence of meleated polypropylene (PP‐g‐MAH) on the properties and compatibility of IFR polypropylene (PP) composites were studied. The results obtained from mechanical tests, rheological behavior of composites, and scanning electron microscope showed that PP‐g‐MAH was a true coupling agent for IFR/PP blends and did not change the necessary flame retardancy. The cocrystallization between bulk PP and PP segments of PP‐g‐MAH was also proven by WAXD analysis. Flow test showed that the flow behaviors of composites in the melt are those of a pseudoplastic and it is very small for PP‐g‐MAH affecting rheological behavior of the PP/IFR composite. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 85: 257–262, 2002
Formation of micron‐sized cycloolefin copolymer from toluene solution using compressed HFC‐134a as antisolvent
Authors: Hsu Ren‐Yong , Tan Chung‐Sung , Chen Jen‐Min
Published: August 2002

A precipitation process employing 1,1,1,2‐tetrafluoroethane (HFC‐134a) as antisolvent was studied to see its feasibility for the separation of cycloolefin copolymer (COC) from toluene solution. The precipitation was carried out by spraying toluene solution containing 3 to 12 wt % of COC through a 0.4‐mm nozzle into a compressed HFC‐134a environment. More than 95% of COC could be precipitated under the conditions that both gas and liquid HFC‐134a phases were present in the precipitator. The effects of temperature, pressure, COC concentration, HFC‐134a flow rate, toluene solution flow rate, and liquid level in the precipitator on yield and morphology of the precipitated COC were systematically studied. Microspheres of COC with a narrow size distribution were exhibited for the COC concentration equal to or less than 5 wt %. The precipitation at these COC concentrations followed a nucleation and growth mechanism. Nucleation and solution breakup that affected morphology and size of the precipitated COC were allowed to occur in the gas space above the liquid. For the concentrations of 8, 10, and 12 wt %, fibers and films instead of microspheres were exhibited. The porosity of the precipitated COC was found to decrease with increasing the COC concentration, indicating that the precipitation was under a spinodal decomposition mechanism. The molecular weight and glass‐transition temperature of the precipitated COC were found to be sufficiently close to those of the virgin chips, indicating that HFC‐134a is an appropriate antisolvent to achieve separation of polymer from solution. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 1657–1668, 2002; DOI 10.1002/app.10543
Thermal degradation of the epoxy system BADGE n = 0/1,2‐DCH immersed in hydrochloric acid
Authors: Núñez M. R. , Núñez Lisardo , Villanueva M. , Rial B.
Published: August 2002

The thermal degradation of an epoxy system consisting of diglycidyl ether of bisphenol‐A and 1,2‐diamine cyclohexane (BADGE n = 0/1,2‐DCH), immersed in hydrochloric acid for 30 days, was studied by thermogravimetric analysis, to determine the reaction mechanism of the degradation process. The results were compared with experimental data corresponding to the same epoxy system without exposure to the acid. It was found that the kinetic reaction mechanism changed with the immersion in HCl. The average activation energy of the solid‐state process was determined by using the Flynn‐Wall‐Ozawa method, resulting in 81 ± 2 kJ/mol. Different integral and differential methods and different reaction mechanisms reported in the literature were used and compared to this value. Analysis of experimental results suggests that in the conversion range studied, 5–20%, the reaction mechanism is somewhere between the different types of phase boundary controlled reaction and random nucleation with one nucleus on the individual particle. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 85: 371–375, 2002
New optically active poly(ester‐imide)s derived from N,N′‐(4,4′‐carbonyldiphthaloyl)‐bis‐L‐phenylalanine diacid chloride
Authors: Mallakpour Shadpour E. , Hajipour Abdol‐Reza , Zamanlou Mohammad‐Reza
Published: August 2002

New optically active poly(ester‐imide)s containing benzophenone tetracarboxylic and L‐phenylalanine moieties were synthesized from N,N′(4,4′‐carbonyldiphthaloyl)‐Bis‐L‐phenylalanine diacid chloride (1) with several aromatic diols such as phenolphthalein (2a), hydroquinone (2b), 2,4‐dihydroxyacetophenone (2c), 1,8‐dihydroxyanthraquinone (2d), bisphenol‐A (2e), 1,5‐dihydroxynaphthalene (2f), 1,4‐dihydroxyanthraquinone (2g) and 4,4′‐dihydroxybiphenyl (2h) by low‐temperature solution polycondensation in CHCl3/Et3N solution. The polymerization reactions were started at 0°C and proceeded at room temperature, producing a series of optically active poly (ester‐imide)s with inherent viscosities of about 0.12–0.31 dL g−1. All of the above polymers are optically active and have been fully characterized by IR spectroscopy, elemental analyses, and specific rotation. Thermal properties of the poly(ester‐imide)s have been investigated using thermal gravimetric analysis. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 85: 315–320, 2002
Crosslinking in polyethylene films by oxidation on metals
Authors: Lin D. G. , Vorobieva E. V.
Published: August 2002

The kinetics of oxidative conversions, such as accumulation of carbonyl groups and crosslinks in polyethylene films that were subjected to oxidation on metallic substrates differing in activity (e.g., copper and aluminum), was investigated. It was learned that the rate and ultimate level of crosslinking in the polymer oxidized on copper were higher than those on aluminum. It is believed that this situation is related to the catalytic effect of the copper compounds transferred into the polymer volume at the regimes of contact oxidation. The amounts of transferred metal were approximately equal in both the soluble and the insoluble fractions of the polymer. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 2776–2783, 2002
Insolubilization of sodium chondroitin sulfate by forming a semi‐interpenetrating polymer network with acrylic acid: A potential carrier for colon‐specific drug delivery
Authors: Wang L. F. , Wang J. M. , Chiang Y. L.
Published: August 2002

To reduce the highly hydrophilic property of chondroitin sulfate (ChS), a semi‐interpenetrating polymer network (semi‐IPN) of chondroitin sulfate/polyacrylic acid (PAA) was prepared as a drug carrier by crosslinking acrylic acid with diethyleneglycol diacrylate. The swelling properties of the semi‐IPNs with different concentrations of crosslinking agent were correlated. The moisture sorption profiles were evaluated using differential thermal analysis. Ketoprofen was used as a drug probe to evaluate the performance of the drug released from the semi‐IPN matrices. The prepared semi‐IPNs demonstrated significant swelling reduction properties with both gastric and intestinal fluids compared with those of both the pure ChS and the ChSAA blend without the crosslinking agent. The amount of accumulated drug released from the semi‐IPNs was less than 30 wt % at pH 1.2 and up to 80 wt % at pH 7.4. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 85: 114–122, 2002
Effect of the pressure on the crystallization behavior of polyamide 66
Authors: Won J. C. , Fulchiron R. , Douillard A. , Chabert B. , Varlet J. , Chomier D.
Published: August 2002

The crystallization behavior of polyamide 66 under high pressure up to 2500 bar was investigated by the use of dilatometric and calorimetric techniques in nonisothermal and isothermal conditions. The solid–solid Brill transition is detected from the evolution of the specific volume in the PVT diagram. The variation of supercooling was examined under different pressures and temperatures. In nonisothermal conditions, when the same cooling rate is applied, the crystallization supercooling is not changed for different pressures. In isothermal conditions, for a given temperature, a pressure increase extends the crystallization supercooling. By the analysis of melting peaks of samples crystallized in different conditions of pressure and temperature, we can conclude that the increasing of the crystallization supercooling leads to a decrease of the lamellae thickness. Finally, the evolution of the thermodynamic equilibrium melting temperature according to pressure was examined. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 80: 1021–1029, 2001