bluuebunny/crossref_metadata_2025_split huggingface dataset:
Exploitation of the complex chemistry of hindered amine stabilizers in effective plastics stabilization
Authors: Pospíšil J. , Pilař J. , Nešpůrek S. 
Published: July 2007

AbstractHindered amine stabilizers (HAS) remain a prominent class of stabilizers having a fortunate development with continuous interest in shaping the future properties of plastics: increase in polymer durability, application extension, reaching new effects. Commercial tests provided much information. Insufficient mechanistic interpretations of the complex effects of environmental factors (harshness of testing, penetration of radiation and oxygen, superposition of temperature, atmospheric impurities) and those of the microenvironment (morphology of the polymer matrix, physical relations of HAS–polymer, interference between HAS and other additives) are a drawback. Model experiments complement commercial studies and explain some phenomena. A careful transfer of information from model experiments must be done to avoid misinterpretation of mechanisms, particularly of the HAS regenerative cycle. A critical analysis of primary steps of the HAS activity mechanism in the polymer matrix based on HAS‐related primary nitroxides, formation of their stationary concentration and concentration gradients influenced by polymer morphology, spatial competition between autoreactions, and oxidation of polymer‐developed alkyl radicals and their scavenging by nitroxides (the key process of HAS efficiency) is outlined. Cyclic regeneration of nitroxides affected by the structure of the amino moiety in the HAS molecule, influence of acid environment, atmospheric ozone or singlet oxygen, cooperative mixtures of HAS with UV absorbers, combinations with additives increasing the thermal stabilization effect and improving color retention, assessment of the heat stabilization performance of HAS by proper testing, and influence of the molecular weight of HAS are mentioned together with examples of the chemical consumption of HAS in the final phases of their lifetime. lifetime. J. VINYL ADDIT. TECHNOL., 13:119–132, 2007. © 2007 Society of Plastics Engineers
Considerations affecting landfill biodegradability of PVC
Authors: Grossman Richard F. , Schleicher John E. , D'Alessio Lorna 
Published: July 2007

AbstractThe combination of tin carboxylate heat stabilizer and a dimethylaminopropyl methacrylamide‐titanate adduct enables anaerobic landfill decomposition of plasticized poly(vinyl chloride) (PVC). Through a mechanism as yet not understood, the above combination directs decomposition under anaerobic conditions to chain scission, thus lowering molecular weight to the point of vulnerability to microorganisms. J. VINYL ADDIT. TECHNOL., 13:133–135, 2007. © 2007 Society of Plastics Engineers
Development of resistance to biocides used in vinyl
Authors: Grossman Richard F. 
Published: July 2007

AbstractThe opportunistic bacterium Pseudomonas fluorescens and the predatory fungus Trichoderma viride can develop heritable resistance to the common broad spectrum biocide Captan. Another biocide commonly used in vinyl compositions to replace organic arsenic compounds, zinc pyrithione, appears more difficult to mutate against. J. VINYL ADDIT. TECHNOL., 13:136–137, 2007. © 2007 Society of Plastics Engineers
Vinyl meeting today's and tomorrow's indoor air quality requirements
Authors: Borrelli Frank E. 
Published: July 2007

AbstractThe growth of the “green” building market has raised new questions about the indoor air performance of building products. Indoor air pollution can consist of chemical, biological, and particulate irritants. Vinyl products have been shown to be well suited with respect to indoor air criteria as defined in current standards and “green” building guidelines. People spend more that 80% of their time indoors. Measurements have shown that levels of some indoor air contaminants can be many times higher than those outdoors. Known sources and factors for poor indoor air quality include tobacco smoke, radon, microbial contamination, dust, pet dander, fibers, and particulates. But they seem to be secondary to public concern for chemical emissions from products. Concerns of health effects from certain chemical air pollutants at even very low concentrations (parts per billion) in the workplace and the home have driven suppliers to test their products for emissions in order to assess the impact of those products on indoor air quality. Technology and methods to evaluate the indoor air performance of products have advanced over the past decade. State, federal, and green building rating guidelines with health‐based exposure limits have evolved both domestically and globally. At the same time, the use of vinyl as a replacement for traditional materials and products in the building and construction sector continues to grow. New uses such as vinyl decking and rail, vinyl moldings and trims, along with new flooring and wall covering designs, have increased the use of vinyl in both exteriors and interiors of buildings. Product manufacturers' attention to impacts of products on indoor air quality has resulted in the development of new innovative vinyl compounds and new installation methods. Taken together, these improvements allow vinyl products to meet and exceed even the evolving target for product performance from an indoor air quality perspective. Many of these products require less maintenance and cleaning, thus resulting in lowering of indoor pollutants. Although technical successes have evolved, commercial success will depend on a conscientious consumer. J. VINYL ADDIT. TECHNOL., 13:138–142, 2007. © 2007 Society of Plastics Engineers
Polypropylene/polysulfone compatibilized blends
Authors: Lawal S. , Flaris V. 
Published: July 2007

AbstractPolypropylene and polysulfone have not been previously blended because of viscosity and processing temperature differences. These blends, which showed structure‐property improvements with the addition of functional polyolefins, were made into environmentally friendly membranes. J. VINYL ADDIT. TECHNOL., 13:143–146, 2007. © 2007 Society of Plastics Engineers
Effect of filler partitioning on the mechanical properties of TPO/nanosilica composites
Authors: Liu Yiqun , Kontopoulou Marianna 
Published: July 2007

AbstractNanosilica (SiO2) is used as a reinforcing filler in PP/elastomer thermoplastic polyolefin (TPO) blends containing ethylene‐octene polyolefin elastomer (POE), ethylene‐propylene rubber (EPR), and maleated EPR. The localization and dispersion of the filler are controlled by adding maleated derivatives to the matrix or the dispersed phase. A separated morphology, consisting of SiO2 residing in the PP matrix, is necessary to achieve improvements in modulus. Filled TPOs containing POE have the best performance and exhibit improved moduli while retaining high values of elongation. J. VINYL ADDIT. TECHNOL., 13:147–150, 2007. © 2007 Society of Plastics Engineers
The chemistry of polymerized oils. II. Dehydro‐polymers of methyl linoleate and methyl stearate
Authors: Clingman A. L. , Sutton Donald A. 
Published: July 2007

Summary

Reaction of methyl linoleate with di‐tert.‐butyl peroxide yields tert.‐butyl alcohol and dehydro‐polymers of methyl linoleate as the main products.

The dehydro‐dimers and higher dehydro‐polymers of methyl linoleate contain conjugated diene unsaturation, thus indicating the involvement of the pentadiene system −CH=CH−CH2−CH=CH− in the reaction.

Methyl stearate yields dehydro‐polymers on reaction with di‐tert.‐butyl peroxide, thus indicating that reaction can occur at points in the fatty acid chains not activated by the proximity of olefinic double bonds.
The solvent extraction of cottonseed
Authors: Hutchins R. P. 
Published: July 2007

SummaryThere are three commercially proven methods of solvent‐extracting cottonseed. They are: pre‐press and extract, extract raw cottonseed flakes, and extract cooked cottonseed meats. Each of these methods of processing has advantages and disadvantages compared to the others. A comparison of installation costs, operating costs, extraction efficiency, and product quality has been made. The conclusion is drawn that the best method of extraction for an individual mill depends upon what equipment is available.Plants which have existing mechanical screw presses or expellers available should probably stick to the pre‐pressing and extraction method. Mills with cookers and hydraulic presses should consider the direct extraction of cooked or raw cottonseed. If a mill wishes to process soybeans as a secondary crop, the extraction of raw cottonseed flakes is relatively more advantageous than for mills who have no intention of processing soybean. If peanuts are a secondary crop, the pre‐press‐extraction combination is best.
Displacement of the double bonds during hydrogenation of unsaturated fatty acid methyl esters
Authors: Boelhouwer C. , Gerckens J. , Lie Ong Tian , Waterman H. I. 
Published: July 2007

SummaryThe displacement of the double bond of several unsaturated fatty acid methyl esters during hydrogenation with a nickel‐kieselguhr catalyst at 180°C. was investigated. The analysis of the dicarboxylic acids (obtained by oxidation of the reaction products with KMnO4 in acetic acid solution) by means of partition chromatography enabled a reliable semiquantitative determination of the position isomers formed.During hydrogenation of methyl esters of oleic, elaidic, petroselinic, and linoleic acid formation of large amounts of position isomers was proved to occur. Migration of the double bonds in both directions took place but was in all cases strongly pronounced in a direction opposite the ester group. The place and configuration (cis or trans) of the double bonds in the starting material apparently were of little importance in this respect. It follows that hydrogenation of fatty acid esters leads to products which are far more complicated, as is generally known. This is especially of importance with respect to the application of hydrogenated fatty oils in the food industries.
Low‐temperature solvent fractionation of animal fats. Part I. Evaluation of anhydrous solvents for crystallization of white grease
Authors: Cording James , Willard Miles J. , Edwards Paul W. , Eskew Roderick K. 
Published: July 2007

Summary and ConclusionsThe work thus far completed establishes some of the conditions required for fractionation of white grease by crystallization from five selected solvents. It has been shown that satisfactory fractionation is possible with any of these solvents by controlled crystallization from solutions containing one part of white grease to five parts of solvent by weight. For each solvent the effect of crystallization temperature on the yield and quality of the liquid fraction (as indicated by titer, pour point, and iodine value) has been determined. Preliminary information has been obtained regarding the effects of wash solvent volume, wash solvent temperature, and holding‐time at crystallization temperature. These data apply only to water‐free solvents. The presence of relatively small amounts of water in acetone, of the order of 2%, reduces its solubility for white grease to such an extent that the grease is separated from the solution as a liquid phase at temperatures above the point where fractionation occurs. The other solvents, methyl ethyl ketone, methyl isobutyl ketone, isopropyl acetate, and ethyl acetate, offer the advantage of separating water in excess of about 2 to 10% while retaining the grease in solution.Before a choice of solvent can be made for pilot‐plant investigation, it is evident that additional research will be required. It is planned to extend the present work in the prepilot‐size crystallizer to evaluate the fractionating efficiency, in the white grease process, of these solvents saturated with water. Operations on a larger continuous pilot‐plant scale will be required subsequently to determine the final choice of solvent, to obtain data for cost estimates and design, and to prepare quantities of various liquid fractions for commercial evaluation.
Preliminary studies on the application of certain chlorinated solvents to soybean oil extraction
Authors: Arnold Lionel K. , Carvey Robert M. 
Published: July 2007

SummaryData for specific‐gravity concentration curves were determined for soybean oil miscellas, using methyl chloroform, ethylene dichloride, and propylene dichloride as solvents. Extraction rates of five solvents extracting soybean oil were found to increase in the following order: 1,2,3‐trichloropropane, methyl chloroform, ethylene dichloride, propylene dichloride, and trichloroethylene. As the result of pilot plant runs on ethylene and propylene dichlorides and consideration of other data the preliminary conclusion was reached that propylene dichloride could be used at a higher temperature where it would be more satisfactory than ethylene dichloride but less so than trichloroethylene.
Loss of oil in hulling tung fruit in the field and at the mill
Authors: McKinney R. S. , Holmes R. L. , Minor J. C. , Potter G. F. 
Published: July 2007

SummaryMethods for analyzing commercial tung hulls for oil have been developed. Samples of tung hulls from mill and field hulling operations have been collected and analyzed. The loss of oil when the fruit are hulled was found to vary from 0.6% to 7.3% with an average loss of 2.7% based on the total amount of oil in the fruit. The difference in the loss of oil between grove and mill hulling was not significant. With a loss of 2.7% of the oil in hulling, a recovery of 87.9% oil on the hulled nuts would be equivalent to a recovery of 85.5% oil on the whole fruit.
Note on the use of calcium hydroxide in the preparation of peanut protein
Authors: Pominski Joseph , Gordon W. O. 
Published: July 2007

SummaryIt was shown in laboratory peptizations that between the pH range of 7.2 and 9.5, nitrogen solubility obtained with calcium hydroxide solution was a constant and was practically equal to the value obtained with use of sodium hydroxide solution at pH 7.5. Pilot‐plant yields of protein and settling rates of protein curds from calcium hydroxide‐peptized solution with the use of sulfur dioxide to lower the pH were equal to those obtained previously from sodium hydroxide‐peptized solution. This information may be of interest in any instance in which it is advantageous to use the lower‐priced peptizing material.
Minimally Invasive Video‐Assisted Thyroidectomy for Small Follicular Thyroid Nodules
Authors: Hegazy Mohamed A. F. , Khater Ashraf A. , Setit Ahmed E. , Amin Mahmoud A. , Kotb Sherif Z. , Shafei Mohamed A. El , Yousef Tamer F. , Hussein Osama , Shabana Yousef K. , Dayem Ola T. Abdel 
Published: July 2007

AbstractMinimal access surgery in the thyroid compartment has evolved considerably over the past 10 years and now takes many forms. This study examined the feasibility and reliability of minimally invasive thyroid surgery for the management of small benign thyroid lesions. A total of 68 patients with small thyroid nodules admitted to the Oncology Center of Mansoura University, Egypt, were enrolled in this prospective randomized trial. Patients were allotted to one of two procedures: minimally invasive video‐assisted thyroidectomy (MIVAT) or minimally invasive open thyroidectomy using the Sofferman technique of strap muscle transection. Exclusion criteria were nodules > 4 cm, presence of thyroiditis, and thyroid gland volume > 20 ml. Preoperative diagnosis, operating time, blood loss, postoperative pain, complications, and cosmetic outcome were all evaluated. The MIVAT group included 35 patients, and the Sofferman group included 33 patients. The main preoperative pathology was a benign follicular lesion (70.5%), and the main postoperative final pathology was follicular adenoma (54.4%). The two groups were comparable regarding age, sex, and extent of thyroid surgery. Operating time was significantly longer in the MIVAT group (115.4 ± 33.5 minutes) compared to the Sofferman group (65.6 ± 23.7 minutes). The postoperative course was significantly less painful in the MIVAT group (p < 0.05). Although patients in the MIVAT group had smaller incisions (p < 0.05), the cosmetic outcome in the two groups was comparable. No long‐term complication was encountered in either group. Two distinct approaches of minimally invasive thyroidectomy are now available and can be performed safely in selected patients. Despite some MIVAT advantages of less postoperative pain and slightly better cosmesis, minimally invasive open thyroidectomy offers an advantage of less operating time with comparable cosmetic results.
Variation in juvenile growth rates among and within latitudinal populations of the medaka
Authors: Yamahira Kazunori , Takeshi Kenichi 
Published: July 2007

AbstractIn ectotherms, lower temperatures at high latitudes would theoretically reduce annual growth rates of individuals. If slower growth and resulting smaller body size reduce fitness, individuals at high latitudes may evolve compensatory growth. This study compares individual growth rates among and within 12 latitudinal populations of the medaka (Oryzias latipes). Growth rates during juvenile stage were measured in a common, temperature‐controlled (28°C) environment. The results revealed that juvenile growth rates differed significantly among the populations. Growth rates were, moreover, significantly correlated with latitudes of source populations, such that higher‐latitude individuals grew faster. Significant variation in growth rates among full‐sib families within populations was also demonstrated. The results strongly suggest that higher‐latitude O. latipes have acquired a greater capacity for growth as an adaptation to shorter growing seasons (which would reduce annual growth rates), thus refuting probability processes, i.e., genetic drift, founder, or bottleneck effects, as a cause of the among‐population variation.
A variational treatment for general elliptic equations of the flame propagation type: regularity of the free boundary
Authors: Teixeira Eduardo V. 
Published: July 2007

We develop a variational theory to study the free boundary regularity problem for elliptic operators:

Lu = D_{j}(a_{ij}(x)D_{i}u) + b_{i}u_{i} + c(x)u = 0

in

\{u > 0\}

,

〈a_{ij}(x)\mathrm{∇}u,\mathrm{∇}u〉 = 2

on

\partial \{u > 0\}

. We use a singular perturbation framework to approximate this free boundary problem by regularizing ones of the form:

Lu_{ɛ} = \beta _{ɛ}(u_{ɛ})

, where

\beta _{ɛ}

is a suitable approximation of Dirac delta function

\delta _{0}

. A useful variational characterization to solutions of the above approximating problem is established and used to obtain important geometric properties that enable regularity of the free boundary. This theory has been developed in connection to a very recent line of research as an effort to study existence and regularity theory for free boundary problems with gradient dependence upon the penalization.

Résumé

Nous développons une théorie variationnelle pour l'étude du problème de la régularité de la frontière libre pour des opérateurs elliptiques :

Lu = D_{j}(a_{ij}(x)D_{i}u) + b_{i}u_{i} + c(x)u = 0

en

\{u > 0\}

,

〈a_{ij}(x)\mathrm{∇}u,\mathrm{∇}u〉 = 2

en

\partial \{u > 0\}

. Nous régularisons et approximons la frontière libre par une méthode de perturbation singulière de la forme :

Lu_{ɛ} = \beta _{ɛ}(u_{ɛ})

, où

\beta _{ɛ}

est une approximation adaptée de la fonction delta de Dirac

\delta _{0}

. Une caractérisation variationnelle des solutions du problème d'approximation ci-dessus est établie et employée pour obtenir les propriétés géométriques importantes qui impliquent la régularité de la frontière libre. Cette théorie a été développée en connection avec une ligne très récente de recherche comme effort pour étudier la théorie d'existence et de régularité pour des problèmes de la frontière libre avec la dépendance de gradient sur la pénalisation.
Total or subtotal hysterectomy for benign uterine diseases? A meta‐analysis
Authors: GIMBEL HELGA 
Published: July 2007

AbstractBackground. Total and subtotal abdominal hysterectomy for benign indications have been compared in randomized clinical trials and observational studies. A meta‐analysis is performed to summarize the evidence. Methods. Thirty‐four randomized clinical trials and observational studies comparing total and subtotal abdominal hysterectomy for benign indications were included. Endpoints were self‐reported urinary incontinence, postoperative complications, operation time, quality of life, constipation, prolapse, sexual functioning, pelvic pain, and cervical stump problems after subtotal hysterectomy. Odds ratios and tests for heterogeneity and overall effect were calculated. Results. Urinary incontinence and prolapse showed a significant difference favoring the total hysterectomy. Some of the women having a subtotal hysterectomy had cervical stump problems (bleeding and abnormal smear). Operation time and peroperative bleeding are postoperative complications were significantly in favor of the subtotal hysterectomy. Lower urinary tract symptoms other than incontinence, quality of life, constipation, pelvic pain, and sexual life were not in favor of either of the hysterectomy methods. Conclusion. Less women suffered from urinary incontinence and prolapse and cervical stump problems after total than after subtotal hysterectomy. However, subtotal hysterectomy is faster to perform, has less peroperative bleeding, and seems to have less intra‐ and postoperative complications.
Effect of passive uterine straightening during embryo transfer: a systematic review and meta‐analysis
Authors: ABOU‐SETTA AHMED M. 
Published: July 2007

AbstractBackground. Part of the success of ultrasound‐guided embryo transfer has been associated with the beneficial effect of uterine straightening by passive bladder distention. Even so, this has not been properly analysed in the literature. Methods. This is a systematic review and meta‐analysis of prospective, randomised, controlled trials, comparing embryo transfer with a full versus empty bladder. Electronic (e.g. PubMed, EMBASE, Cochrane Library) and hand searches were performed to locate trials. Primary outcomes were live‐birth, ongoing and clinical pregnancy rates. Secondary outcomes were rates of implantation, miscarriage, multiple and ectopic pregnancies, and retained embryos. Also, the ease of transfer, need for instrumental assistance, and presence of blood on the catheter tip were evaluated. Four studies were identified, of which 1 study was excluded. Meta‐analysis was conducted with the Mantel–Haenszel method, utilising the fixed‐effect model. Results. For the primary outcome measures, no data was available for the LBR rate. There was a significantly higher chance of an ongoing pregnancy [OR = 1.44 (95% CI = 1.04–2.04)] and clinical pregnancy [OR = 1.55 (95% CI = 1.16–2.08)] with a full bladder. For the secondary outcomes, there was a significantly greater incidence of difficulty, or need for instrumental assistance, with an empty bladder. Other outcome measures were not significantly different. Conclusion. There is evidence in the literature advising to fill the bladder prior to embryo transfer.