bluuebunny/crossref_metadata_2025_split huggingface dataset:
Chloroform Extract of Reclaimed Rubber
Authors: Palmer Henry F. , Kilbourne F. L. 
Published: February 2011

Abstract
1. For any given reclaim, increased chloroform extract means greater softness and plasticity, but different types of reclaim with equivalent chloroform extracts may have widely different plasticities, or with the same workability may have widely different chloroform extracts. 2. While longer time of heat treatment at a given temperature increases the chloroform extract, increased temperature raises it decidedly. At elevated temperature (263° C) there is a transformation of chloroform-soluble into acetone-soluble material. 3. Within practical operating temperature limits, the milling and straining operations do not affect the chloroform extract. Increased number of passes through a refiner increases the chloroform extract. This fact is of importance in the chloroform determination. Cool refining gives a product with higher chloroform extract than hot refining. 4. The chloroform extract is unaffected by slow or rapid cooling of finished reclaim slabs. The slow-cooled reclaim, however, is somewhat drier and nervier. 5. Reclaimed rubber has a lower chloroform extract after natural aging than when freshly made. The aging process is also accompanied by an increase in the nerve and a decrease in the tackiness of the reclaim. 6. The use of oils as plasticizers in preference to excessive heat plasticization is not detrimental to reclaim quality, but is often desirable in producing many types of reclaimed rubber. 7. The percentage of chloroform extract present in typical commercial reclaims usually lies between 30 and 40 per cent, based on the rubber content. Values below 20 per cent indicate a low degree of devulcanization. Values above 50 per cent are rare but, when they do occur, indicate an excessive devulcanization. The amount of chloroform extract is an insensitive criterion of workability. Since a high chloroform extract does not indicate improved quality, a performance test must be used.
Production of Decorative and Ornamental Rubber Products
Authors: Griffiths J. P. , Pinnell C. R. 
Published: February 2011

Abstract
It is proposed to deal with the production of rubber goods which can lay claim to being decorative and ornamental, not according to their classification in a sales catalog, but according to the machines which produce them. CALENDERING One of the difficulties in a works handling rubber qualities ranging from pure gum stocks to the more heavily compounded variety, such as flooring, is to obtain sheets of the same thickness across the width. The wider the sheet the more difficult this becomes. With perfectly cylindrical rolls, the pressure of the rubber bank at the nip will cause the roll to bend, so that a sheet of rubber coming from between such rolls will be thicker in the middle. This variation is overcome by making the rolls a little thicker in the middle by only a few thousandths. However, the amount of bending depends on the type of stock being calendered, so that one calender cannot produce sheet of even thickness from all types of mixings. The greater thickness of the rolls in the middle compared with the ends is referred to as the camber. When the machine is under load, the camber corrects the bending so that the effect is equivalent to using perfectly cylindrical rolls that do not bend. Unless a firm has more than one calender for different types of stock, there is always one class of mix which cannot be the correct thickness right across the sheet. For many classes of goods this variation is not important, but for sheets of rubber intended for flooring to be cut to tiles and pure gum sheet to be cut to thread, it is obvious how important the question of uniform thickness becomes. One cannot expect mechanical pressure during vulcanization to correct this fault or, if it does, other effects are spoilt. For example, the marble pattern on flooring may be spoilt by a sideways flow of rubber under a powerful press, especially where considerable variation was present in the thickness of the calendered sheet. A recent method of correcting camber is to swing the top bowl of, say, a three-bowl calender, so that the axis of one bowl is at an angle to the one immediately underneath. The rollers are, of course, perfectly cylindrical, and only have to be swung through a few degrees.
Vulcanization of Rubber Compounds
Authors: Booth E. W. , Beaver D. J. 
Published: February 2011

Abstract
1. Rubber dissolves approximately one per cent of hydrogen sulfide when saturated at room temperature. 2. All types of commercial accelerators are retarded in rate of vulcanization as a result of treatment with hydrogen sulfide, and the retardation is directly proportional to the hydrogen sulfide content. 3. The physical properties of mercaptobenzothiazole types of accelerators and diphenylguanidine are not permanently affected by hydrogen sulfide, but dithiocarbamates, thiuram sulfides, aldehydeamines and litharge are permanently affected. 4. Rubber compounds containing mercaptobenzothiazole types of accelerators or diphenylguanidine, which have been treated with hydrogen sulfide and then degassed in a vacuum oven, show normal rate of vulcanization. Compounds containing aldehydeamines, litharge or carbon black show permanent retarding, even after degassing. 5. Increased zinc oxide or sulfur has no appreciable effect on the retardation. 6. Little or no zinc sulfide is formed as a result of treatment with hydrogen sulfide. 7. Hydrogen sulfide treatment of rubber compounds retards the rate of combination of sulfur with rubber. 8. In no case did hydrogen sulfide treatment improve the physical properties of the vulcanizate.
Studies in the Sterol Group. Part XLIII. The Unsaponifiable Portion of the Acetone Extract of Plantation Rubber
Authors: Heilbron I. M. , Jones E. R. H. , Roberts K. C. , Wilkinson P. A. 
Published: February 2011

Abstract
In previous studies of this material, the isolation and identification of a sterol, C27H46O, and octadecyl alcohol have been described. It is now shown that the former is a mixture of isomeric sterols, which include β-sitosterol and probably a 24,28-dehydrostigmastanol, and that the aliphatic alcohol is eicosyl alcohol. No other pure component has yet been isolated in sufficient quantity for investigation, since the remainder of the neutral action undergoes extensive pyrolysis on distillation, even in a high vacuum. Evidence has, however, been obtained that a portion of the unsaponifiable substances becomes increasingly intractable as rubber ages, and it is possible that the present failure to obtain the ketone C15H24O and the socalled liquid sterols, C27H42O3 and C20H30O, reported by Bruson, Sebrell, and Vogt, may be due to this cause.
Rubber, Polyisoprenes, and Allied Compounds. IV. The Relative Tendencies towards Substitutive and Additive Reaction during Chlorination
Authors: Bloomfield George F. 
Published: February 2011

Abstract
Although the established mode of reaction of chlorine with unsaturated systems is primarily additive, it has recently been shown by Groll and his collaborators that, under suitable conditions, substitutive reaction may not only occur but may become the major reaction, to the exclusion of addition. According to these authors, high temperatures in the range of 300–600° seemed generally to be necessary if substitutive reaction is to predominate, but subsequently it was shown by Rust and Vaughan that a considerable degree of substitutive reaction can be realized at temperatures in the range 130–200°, provided certain catalysts which produce free radicals in contact with the halogen are present. The polyisoprene system has been found to be particularly susceptible to substitutive attack by oxygen, and it has long been known that, judged by the quantity of hydrogen chloride liberated, the chlorination of rubber proceeds largely by substitution in the earlier stages of reaction. The character of the products thus produced and the influence of the experimental conditions on the course of reaction were not, however, studied in any detail by McGavack.
Determination of Total Sulfur in Rubber
Authors: Luke C. L. 
Published: February 2011

Abstract
With the recent increase in research on natural and synthetic rubber, there has arisen a need for a rapid method for the determination of total sulfur in rubber samples where only a semimicrosample can be spared for analysis. The usual methods in which the rubber is oxidized by digestion with acid, followed in some cases by fusion to complete oxidation, and the sulfur is precipitated and weighed as barium sulfate, yield good results on semimicro-samples, but are time-consuming, because quantitative precipitation of the sulfate cannot be attained unless the solution is allowed to stand overnight before filtration. Several volumetric methods, most of which depend on the precipitation of sulfur as barium sulfate, have been described, but none is very satisfactory in the determination of small amounts of sulfur. St. Lorant has proposed a volumetric method for the determination of microsamples of sulfate, in which the sulfate is reduced to sulfide with hydriodic acid, and the hydrogen sulfide is distilled off and determined colorimetrically. The author has recently developed a modification of this method which has proved to be very satisfactory for the analysis of sulfur in small samples of rubber. The procedure consists essentially of oxidation of the rubber in the usual manner, reduction of the sulfate to sulfide, separation of the hydrogen sulfide by distillation, and titration of the latter iodometrically. The new method is very rapid (20 to 25 minutes for the distillation and titration), and is not subject to the errors of adsorption, occlusion, and solubility encountered in the gravimetric barium sulfate method, or to difficulties in detection of the end-point encountered in some volumetric methods. It possesses the distinct advantage over some of the gravimetric methods that it is applicable to the analysis of rubber containing barium, lead, and calcium. The only serious objections to the method from the standpoint of general use are that hydriodic acid is expensive and that the applicability of the method is somewhat limited because of the fact that no more than about 5 mg. of sulfur can be handled conveniently. This means that the sample size must be small when analyzing rubber high in sulfur; and when small samples are used there is always the danger of error due to unequal distribution of sulfur in the sample.
The Mechanism of the Action of Mercapto-Benzothiazole and of Its Derivatives in the Vulcanization Process
Authors: Petrov K. D. 
Published: February 2011

Abstract
In our work we confirmed that, in the process of vulcanization of rubber, the normal zinc salt of mercaptobenzothiazole changes into mercaptobenzo-thiazole. Based on this and on other facts described earlier, a probable mechanism of the action of mercaptobenzothiazole and its derivatives in the vulcanization of rubber is suggested.
The Effects of Milling on the Softness of Rubber. I. Temperature and Friction
Authors: Haehl A. , le Bras Jean 
Published: February 2011

Abstract
Although the process of softening rubber by mastication has been the subject of repeated investigation, the literature contains no references to systematic experiments in this field. It is with a view to making up for this lack of information that the work described in the present paper was undertaken. A survey of the literature shows several papers of interest in connection with the work to be described in the present paper, particularly the papers of Grundy and Schidrowitz, Griffiths, The Goodyear Tire and Rubber Company, Shoaff, Bachmann, Behre and Blankenstein, and Busse and Cunningham. Grundy and Schidrowitz attempted to establish a relation between plasticity and work expended in milling. Griffiths studied the influence of the size of batch, temperature, etc., on plasticity. The Goodyear Tire and Rubber Company Laboratories investigated the influence of the temperature during milling on mastication. Shoaff determined the energy expended in mastication. Bachmann, Behre and Blankenstein made a study of the dependence of the mastication on the spacing of the mill rolls, on the speed of the rolls, and on other factors. Finally Busse and Cunningham investigated the dependence of plasticity on the temperature of mastication and on atmospheric oxygen.
Effect of Temperature on the Mechanical Properties of Rubberlike Materials
Authors: Fletcher W. P. 
Published: February 2011

Abstract
In the course of investigations into the mechanical properties of natural and synthetic rubbers intended for use in antivibration devices, variations of a large order were encountered. As these variations seemed to be largely dependent on temperature, a preliminary detailed examination in the region of 5° to 40° C was made. With the aid of a mechanical vibrator somewhat similar to that employed by Gehman, and working at 20–60 c.p.s., measurements of dynamic elastic compression modulus and associated resilience were made by the well known resonance method. A detailed description of the apparatus, method, and results is to be published later; for the present time, it may be said that the test-pieces were in the form of cylindrical rubber blocks, 0.875 inch in diameter and 0.875 inch high, bonded at each end to steel screws by the conventional brass-plate method.
Recent Advances in the Physics and Chemistry of Rubber. I. The Size and Shape of the Rubber Molecule
Authors: Gee Geoffrey 
Published: February 2011

Abstract
During the last decade, enormous strides have been made in the scientific study of rubber and related polymers. The main factors combining to make this possible have been the realization that the physical behavior of these materials depends on their long chain character, while their chemical properties are essentially those of a low molecular substance of similar structure. Contrary to earlier belief, neither the physics nor the chemistry of rubber involves any mysterious new forces or reactivities unknown among smaller molecules. Since such importance attaches to the size and shape of the rubber molecule, we begin by reviewing briefly the evidence on which our present theories are based. Methods of determining molecular weights may be divided into “counting” methods and “weighing” methods. The former include the determination of any of the “colligative” properties of a solution; the latter depends on the use of an ultracentrifuge.
A Modified Method for the Direct Estimation of the Absorption of Oxygen by Rubber
Authors: Van Amerongen G. J. 
Published: February 2011

Abstract
A modification of Dufraisse's oxygen absorption apparatus is described, with which it is possible to carry out the determination under constant pressure. As a result the oxygen absorption of rubber can be read directly in absolute terms, a secondary advantage being that the determination proceeds roughly four times as quickly as by the manometric method. Some results are given which show clearly, among other things, how considerable is the effect of preliminary exposure of the rubber to light on the oxidation.
Diode Laser Cyclophotocoagulation versus Cyclocryotherapy in the Treatment of Refractory Glaucoma
Authors: Tzamalis Argyhos , Pham Duy-Thoai , Wirbelauer Christopher 
Published: February 2011

Purpose The aim of the present study was to evaluate the efficacy of diode laser cyclophotocoagulation (DCPC) and cyclocryotherapy (CCT) in the treatment of refractory glaucoma and compare the postoperative complications and discomfort rates. Methods In a prospective, randomized, controlled clinical study, 40 eyes of 40 patients with refractory glaucoma were randomly assigned in 2 groups of 20 eyes each to receive either DCPC or CCT. Patients underwent follow-up examinations on the first 3 days and then 1 week and 1, 3, 6, and 12 months after initial treatment. Complications and discomfort after treatment using a visual pain analogue scale were recorded. Results In the DCPC group, the mean intraocular pressure (IOP) decreased (p<0.05) from 44.3±16.4 mmHg preoperatively to 24.1±7.6 mmHg, 22.8±5.6 mmHg, and 22.5±5.1 mmHg 3, 6, and 12 months posttreatment, respectively. Regarding the CCT group, the mean IOP was reduced (p<0.05) from 46.5±10.4 mmHg to 26.6±12.2 mmHg, 21.2±7.7 mmHg, and 20.6±5 mmHg at the same time intervals. In the DCPC group, the mean IOP reduction was strongly correlated with the number of laser effects (r=0.65; p<0.01), but 35% needed retreatments. The mean postoperative pain was 5.6±2.9 (DCPC) vs 5.7±2.3 (CCT) (p=0.91). No severe complications were observed. Conclusions Both DCPC and CCT proved to be safe and effective IOP-lowering methods in patients with refractory glaucoma. Diode laser cyclophotocoagulation should be considered as the primary treatment option in refractory glaucoma using an individual treatment dosage.
Relationship Between Erythropoietin Responsiveness, Insulin Resistance, and Malnutrition-Inflammation-Atherosclerosis (Mia) Syndrome in Hemodialysis Patients with Diabetes
Authors: Abe Masanori , Okada Kazuyoshi , Maruyama Takashi , Maruyama Noriaki , Matsumoto Koichi , Soma Masayoshi 
Published: February 2011

Background This study aimed to explore the relationship between recombinant human erythropoietin (EPO) responsiveness, insulin resistance, and malnutrition-inflammation-atherosclerosis (MIA) syndrome in hemodialysis patients. Methods This was an observational cohort study in hemodialysis patients. Adipokines, inflammatory cytokines, and required EPO dosage were measured in diabetes (DM; n=58) and non-diabetes (non-DM; n=58) groups over 48 weeks. Furthermore, the EPO responsiveness index (required EPO dosage divided by hemoglobin) was evaluated with or without MIA syndrome in both groups. Results The DM group had significantly higher plasma leptin, interleukin-6 (IL-6), and high sensitivity C-reactive protein (hs-CRP) levels but lower plasma high molecular weight (HMW) adiponectin levels compared to the non-DM group. Although hemoglobin levels were not significantly different, required EPO dosage was significantly higher in the DM group than in the non-DM group, particularly in the presence of MIA syndrome. The DM group with MIA syndrome had significantly higher plasma leptin, IL-6, and hs-CRP levels but lower plasma HMW adiponectin levels compared to the non-DM group with MIA syndrome. There was also a significant association between EPO dosage and homeostasis model assessment for insulin resistance (HOMA-IR), hs-CRP, IL-6, tumor necrosis factor α, leptin, and HMW adiponectin levels in DM patients with MIA syndrome. Conclusion Diabetic hemodialysis patients with MIA syndrome have a lower response to EPO and a higher resistance to insulin. This fact may explain the poor outcome of these patients and demonstrate the importance of diagnosis and therapeutic management.
Synthesis of Spiroborate Esters from 1,2‐Aminoalcohols, Ethylene Glycol and Triisopropyl Borate: Preparation of (S)‐1‐(1,3,2‐Dioxaborolan‐2‐yloxy)‐3‐Methyl‐1,1‐Diphenylbutan‐2‐Amine
Authors: Stepanenko Viatcheslav , Huang Kun , Ortiz‐Marciales Margarita 
Published: February 2011

Abstract(2S)‐2‐Amino‐3‐methyl‐1,1‐diphenylbutanolBromobenzeneL‐Valine methyl ester hydrochloridePhenylmagnesium chlorideEthylene glycolTriisopropyl borate(‐)‐(S)‐1‐(1,3,2‐Dioxaborolan‐2‐yloxy)3‐methyl‐1,1‐diphenylbutan‐2‐amine
New, Convenient Route for Trifluoromethylation of Steroidal Molecules
Authors: Fei Xiang‐Shu , Tian Wei‐Sheng , Ding Kai , Wang Yun , Chen Qing‐Yun 
Published: February 2011

Abstract

Androst‐4‐ene‐3,17‐dione

Oxirane, 2‐methyl

Bromine

Androst‐4‐ene‐3,17‐dione, 4‐bromo

Acetic acid, 2,2‐difluoro‐2‐(fluorosulfonyl‐methyl ester
Lithium Amides as Homochiral Ammonia Equivalents for Conjugate Additions to α,β‐Unsaturated Esters: Asymmetric Synthesis of (

S

)‐β‐Leucine
Authors: Davies Stephen G. , Fletcher Ai M. , Roberts Paul M. 
Published: February 2011

Abstract

t
‐Butyl diethylphosphonacetate

Methylmagnesium bromide

Isobutyraldehyde

t
‐Butyl (
E
)‐4‐methylbut‐2‐enoate

R
‐alpha‐Methylbenzylamine

R‐N
‐Benzyl‐
N
‐(a‐methylbenzyl)amine

Butyllithium

t
‐Butyl 3[
N‐
benzyl‐N‐(a‐methylbenzyl)amine]‐4‐methylpentanoate

Palladium hydroxide on carbon

t
‐Butyl‐3‐amino‐4‐methylpentanoate

Trifluoracetic acid

(
S
)‐3‐Amino‐4‐methylpentanoic acid

(
S
)‐3‐[
N
‐(
p
‐Toluenesulfonyl)amino}‐4‐methylpentanoic acid
Organocatalytic α‐Methylenation of Aldehydes: Preparation of 3,7‐Dimethyl‐2‐Methylene‐6‐Octenal
Authors: Benohoud Meryem , Erkkilä Anniina , Pihko Petri M. 
Published: February 2011

Abstract

4‐(Dimethylamino)benzoic acid

Pyrrolidine

Citronellal

3,7‐Dimethyl‐2‐methylene‐6‐octenal

Formaldehdye, aqueous
Direct Fluorination of the Carbonyl Group of Benzophenones Using Deoxo‐Fluor®: Preparation of Bis(4‐Fluorophenyl)Difluoromethane
Authors: Chang Ying , Lee Hyelee , Bae Chulsung 
Published: February 2011

Abstract

Dextro‐Fluor

Bis(2‐methoxyethyl)aminosulfur trifluoride

Benzophenone

Bis(4‐fluorophenyl)ketone
Isolation and Expansion of Cardiosphere‐Derived Stem Cells
Authors: Tan Jun‐Jie , Carr Carolyn A. , Stuckey Daniel J. , Ellison Georgina M. , Messina Elisa , Giacomello Alessandro , Clarke Kieran 
Published: February 2011

AbstractThe isolation and in vitro expansion of stem cells from the adult heart may provide a cell therapy for regenerating damaged myocardium. Cardiac stem cells can be isolated via magnetic or fluorescent cell sorting using specific cell‐surface markers, including c‐kit, Sca‐1, and Isl‐1. Because these isolation methods yield relatively few cells, substantial in vitro expansion is required to generate sufficient cell numbers for therapy. An alternative method uses cells spontaneously shed from cultured heart explants, which are harvested, induced to form cardiospheres, and expanded as a monolayer for several passages. This method for generating therapeutically relevant numbers of cells in a shorter time period than cell surface marker–based isolations is ideally suited for autologous cardiac stem cell therapy after myocardial infarction. Curr. Protoc. Stem Cell Biol. 16:2C.3.1‐2C.3.12. © 2011 by John Wiley & Sons, Inc.
Imaging of Endogenous RNA Using Genetically Encoded Probes
Authors: Ozawa Takeaki , Umezawa Yoshio 
Published: February 2011

AbstractImaging of RNAs in single cells revealed their localized transcription and specific function. Such information cannot be obtained from bulk measurements. This unit contains a protocol of an imaging method capable of visualizing endogenous RNAs bound to genetically encoded fluorescent probes in single living cells. The protocol includes methods of design and construction of the probes, their characterization, and imaging a target RNA in living cells. The methods for RNA imaging are generally applicable to many kinds of RNAs and may allow for elucidating novel functions of localized RNAs and understanding their dynamics in living cells. Curr. Protoc. Chem. Biol. 3:27‐37 © 2011 by John Wiley & Sons, Inc.
Preparing DNA Libraries for Multiplexed Paired‐End Deep Sequencing for Illumina GA Sequencers
Authors: Son Mike S. , Taylor Ronald K. 
Published: February 2011

ABSTRACTWhole‐genome sequencing, also known as deep sequencing, is becoming a more affordable and efficient way to identify SNP mutations, deletions, and insertions in DNA sequences across several different strains. Two major obstacles preventing the widespread use of deep sequencers are the costs involved in services used to prepare DNA libraries for sequencing and the overall accuracy of the sequencing data. This unit describes the preparation of DNA libraries for multiplexed paired‐end sequencing using the Illumina GA series sequencer. Self‐preparation of DNA libraries can help reduce overall expenses, especially if optimization is required for the different samples, and use of the Illumina GA Sequencer can improve the quality of the data.