STUDIES ON REACTIONS RELATING TO CARBOHYDRATES AND POLYSACCHARIDES: LII. THE PREPARATION, SEPARATION AND IDENTIFICATION OF THE ISOMERIC PROPYLIDENE, ISOBUTYLIDENE, t-AMYLIDENE AND DIBROMOETHYLIDENE GLYCEROLS AND THE GENERAL PROPERTIES OF GLYCEROL CYCLIC ACETALS

1936 ◽  
Vol 14b (12) ◽  
pp. 415-426 ◽  
Author(s):  
Saul M. Trister ◽  
Harold Hibbert
Keyword(s):  
Physical Properties ◽  
Sulphuric Acid ◽  
Direct Synthesis ◽  
Marked Influence ◽  
Cyclic Acetals ◽  
General Properties ◽  
The Difference ◽  
Acetal Condensation

The condensation of propionaldehyde, isobutyraldehyde, trimethylacetaldehyde and dibromoacetaldehyde with glycerol has been carried out in the presence of a catalyst (40% sulphuric acid) at 90 °C., and the resulting products have been shown to consist in each case of a mixture of the five- and six-membered cyclic acetals. The separation of these isomers from the acetal mixture was rendered possible by the difference in the physical properties of their benzoates. The structure of the latter was proved by saponification, methylation, hydrolysis and isolation of the resulting glycerol α- and glycerol β-methyl ethers respectively.With the isomers from dibromoacetaldehyde this method could not be used, owing to the labile character of the bromine atoms in presence of alkali. Their structures were proved by direct synthesis of the five-membered acetal benzoate from glycerol α-benzoate and dibromoacetaldehyde.The data obtained provide additional evidence of the marked influence exerted by the polar character of the aldehyde on the extent and character of acetal condensation. Increase in the electronegative character increases the amount formed of the five-membered acetal and decreases that of the six-membered. Trimethylacetaldehyde condensed readily with glycerol in absence of a catalyst. Lowering of temperature, in presence of the catalyst, favored the formation of the six-membered acetals, in agreement with the earlier work of van Roon. The results further confirm the Hibbert-Michael Ring Partition Principle.A general comparison is made of the physical properties of the ethylidene–, propylidene–, isobutylidene–, t–amylidene–, bromoethylidene–, and dibromoethylidene glycerol acetals.By substituting diphenylamine for aniline in the synthesis of trimethylacetaldehyde from trimethylpyruvic acid the yield is increased from 25 to 40%.

Physical properties of biaxially oriented PA6 film for simultaneous stretching and sequential processing

2011 ◽  
Vol 31 (1) ◽  
Author(s):  
Masao Takashige ◽  
Toshitaka Kanai
Keyword(s):  
Impact Strength ◽  
Physical Properties ◽  
Physical Property ◽  
High Impact ◽  
Thermal Shrinkage ◽  
Double Bubble ◽  
Biaxial Stretching ◽  
High Impact Strength ◽  
The Difference ◽  
Stretching Process

Abstract There are two different stretching processes that produce the biaxially oriented film, namely the tenter process and double bubble tubular film process. Furthermore, there are two tenter processes, i.e., the sequential biaxial stretching process and simultaneous biaxial stretching process. There is no report describing the difference among film physical properties of the three different processes. The biaxially oriented polyamide film using the double bubble tubular process has good balanced physical property and high impact strength, thus it is used for proper applications utilizing their advantage properties. In this report, the influence of each biaxial stretching process on film physical properties of polyamide, which has hydrogen bond, was studied in detail. As a result, the tentering process film has anisotropic tensile properties between machine direction (MD) and transverse direction (TD). This result was influenced by a later stretching process, namely TD stretching. On the contrary, the double bubble tubular film has good balanced properties, especially thermal shrinkage and impact strength. Tentering simultaneous stretching film has much larger shrinkage in MD than in TD. The sequential stretching film has larger shrinkage in TD than in MD. The double bubble tubular film has high impact strength, because it corresponds to the balanced molecular orientation.

scholarly journals The Secrets of Beautiful Hair: Why is it Flexible and Elastic?

Cosmetics ◽  
2019 ◽  
Vol 6 (3) ◽  
pp. 40 ◽  
Author(s):  
Mikako Ezure ◽  
Noriyuki Tanji ◽  
Yukari Nishita ◽  
Takashi Mizooku ◽  
Shinobu Nagase ◽  
...  
Keyword(s):  
Physical Properties ◽  
Layered Structure ◽  
Outer Layer ◽  
New Technology ◽  
Selective Reduction ◽  
Cell Distribution ◽  
Cortical Cells ◽  
The Difference ◽  
The Relationship ◽  
Hair Surface

Beautiful hair, so called “SHINAYAKA” hair in Japanese, has a good appearance not only when stationary but also when in motion, and it is a highly desirable hair condition for Japanese consumers. We investigated such SHINAYAKA hair, which was selected by sensory evaluation, for the relationship between physical properties, such as flexibility and elasticity, and hair structure. It has already been reported that human hair cortical cells have two types, similar to wool: the ortho-like cortex and the para-like cortex. Microscopic observation revealed that the ortho-like cortex is distributed in the outer layer of the hair (near the hair surface) and the para-like cortex exists in the inner layer (near the center of the fiber). This cell distribution, a concentric double-layered structure, was deemed to be a characteristic of SHINAYAKA hair. Furthermore, analysis of physical properties showed the difference between the elasticity of the outer layer and inner layer, and that this difference was bigger in SHINAYAKA hair compared to other hair. This phenomenon was observed not only in Japanese hair, but also in Caucasian hair. In addition, we have developed a new technology for creating “SHINAYAKA” hair by treatment with succinic acid. Inflexible and inelastic hair can be changed by this treatment, and its flexibility and elasticity improve by selective reduction of stiffness of the outer layer.

A study of the relationships of interactions between Asp-201, Na+ or K+, and galactosyl C6 hydroxyl and their effects on binding and reactivity of β-galactosidase

2004 ◽  
Vol 82 (2) ◽  
pp. 275-284 ◽  
Author(s):  
Julia Xu ◽  
Mary A.A McRae ◽  
Scott Harron ◽  
Beatrice Rob ◽  
Reuben E Huber
Keyword(s):  
Physical Properties ◽  
Negative Charge ◽  
Binding Pocket ◽  
Side Chain ◽  
Wild Type ◽  
Sodium Potassium ◽  
The Difference ◽  
Potassium Binding ◽  
Covalent Intermediate ◽  
Catalytic Effects

The interactions between Na+ (and K+) and Asp-201 of β-galactosidase were studied. Analysis of the changes in Km and Vmax showed that the Kd for Na+ of wild type β-galactosidase (0.36 ± 0.09 mM) was about 10× lower than for K+ (3.9 ± 0.6 mM). The difference is probably because of the size and other physical properties of the ions and the binding pocket. Decreases of Km as functions of Na+ and K+ for oNPG and pNPG and decreases of the Ki of both shallow and deep mode inhibitors were similar, whereas the Km and Ki of substrates and inhibitors without C6 hydroxyls remained constant. Thus, Na+ and K+ are important for binding galactosyl moieties via the C6 hydroxyl throughout catalysis. Na+ and K+ had lesser effects on the Vmax. The Vmax of pNPF and pNPA (substrates that lack a C6 hydroxyl) did not change upon addition of Na+ or K+, showing that the catalytic effects are also mediated via the C6 hydroxyl. Arrhenius plots indicated that Na+, but not K+, caused k3 (degalactosylation) to increase. Na+ also caused the k2 (galactosylation) with oNPG, but not with pNPG, to increase. In contrast, K+ caused the k2 values with both oNPG and pNPG to increase. Na+ and K+ mainly altered the entropies of activation of k2 and k3 with only small effects on the enthalpies of activation. This strongly suggests that only the positioning of the substrate, transition states, and covalent intermediate are altered by Na+ and K+. Further evidence that positioning is important was that substitution of Asp-201 with a Glu caused the Km and Ki values to increase significantly. In addition, the Kd values for Na+ or K+ were 5 to 8 fold higher. The negative charge of Asp-201 was shown to be vital for Na+ and K+ binding. Large amounts of Na+ or K+ had no effect on the very large Km and Ki values of D201N-β-galactosidase and the Vmax values changed minimally and in a linear rather than hyperbolic way. D201F-β-galactosidase, with a very bulky hydrophobic side chain in place of Asp, essentially obliterated all binding and catalysis.Key words: β-galactosidase, sodium, potassium, binding, aspartic acid.

Acoustic Cavitation Behavior in Isopropyl Alcohol Added Cleaning Solution

2012 ◽  
Vol 195 ◽  
pp. 169-172
Author(s):  
Bong Kyun Kang ◽  
Ji Hyun Jeong ◽  
Min Su Kim ◽  
Hong Seong Sohn ◽  
Ahmed A. Busnaina ◽  
...  
Keyword(s):  
Growth Rate ◽  
Physical Properties ◽  
Bubble Growth ◽  
Bubble Collapse ◽  
Particle Removal ◽  
Factors Affecting ◽  
Ultrasound Field ◽  
Cavitation Threshold ◽  
The Difference ◽  
Cavitation Behavior

As the semiconductor manufacturing technology for ultra-high integration devices continue to shrink beyond 32 nm, stringent measures have to be taken to get damage free patterns during the cleaning process. The patterns are no longer cleaned with the megasonic (MS) irradiation in the advanced device node because of severe pattern damages caused by cleaning. Recently, several investigations are carried out to control the cavitation effects of megasonic to reduce the pattern damages. The mechanism of damage caused by an unstable acoustic bubble motion was mainly attributed to the high sound pressure associated with violent bubble collapse [1]. In order to characterize the dominant factors affecting the cavitation, MS cleaning was conducted with various dissolved gas concentrations in water. It was reported that the cavitation phenomena relating to particle removal efficiency (PRE) and pattern damage were considerably changed with the addition of a specific gas [2]. This changing behavior may be due to the difference in the physical properties of dissolved gases associated with acoustic bubble growth rate as a function of their concentration. In particular, cavitation effects induced during MS cleaning was controlled by adjusting the acoustic bubble growth rate. Also the change of bubble growth rate is well explained by both rectified diffusion for single bubble and bubble coalescence for multi-bubble, respectively. Similarly, it is well-known that surface active solute (SAS) in the ultrasound field plays an important role in controlling the cavitation effects. A detailed explanation of the acoustic bubble growth rate, cavitation threshold and their relationship with various types of SAS and concentration of biomedical and chemical reactions perspective have been reported elsewhere [3,4]. Their studies demonstrated that the change of cavitation effects depends not only on the chain length of alcohol in the solution but also on the physical properties such as surface tension and viscosity of SAS solutions.

scholarly journals Effect of Transition Metal Substitution on the Charge-Transfer Phase Transition and Ferromagnetism of Dithiooxalato-Bridged Hetero Metal Complexes, (n-C3H7)4N[FeII1−xMnIIxFeIII(dto)3]

Crystals ◽  
2018 ◽  
Vol 8 (12) ◽  
pp. 446 ◽  
Author(s):  
Masaya Enomoto ◽  
Hiromichi Ida ◽  
Atsushi Okazawa ◽  
Norimichi Kojima
Keyword(s):  
Phase Transition ◽  
Charge Transfer ◽  
Physical Properties ◽  
Mixed Valence ◽  
Ferromagnetic Phase ◽  
Ferromagnetic Transition ◽  
Transfer Phase ◽  
Spin Configuration ◽  
Ion Radius ◽  
The Difference

The dithiooxalato-bridged iron mixed-valence complex (n-C3H7)4N[FeIIFeIII(dto)3] (dto = dithiooxalato) undergoes a novel charge-transfer phase transition (CTPT) accompanied by electron transfer between adjacent FeII and FeIII sites. The CTPT influences the ferromagnetic transition temperature according to the change of spin configuration on the iron sites. To reveal the mechanism of the CTPT, we have synthesized the series of metal-substituted complexes (n-C3H7)4N[FeII1-xMnIIxFeIII(dto)3] (x = 0–1) and investigated their physical properties by means of magnetic susceptibility and dielectric constant measurements. With increasing MnII concentration, x, MnII-substituted complexes show the disappearance of CTPT above x = 0.04, while the ferromagnetic phase remains in the whole range of x. These results are quite different from the physical properties of the ZnII-substituted complex, (n-C3H7)4N[FeII1-xZnIIxFeIII(dto)3], which is attributed to the difference of ion radius as well as the spin states of MnII and ZnII.

Mixed Polymers and Vulcanizable Plasticizers. Relation to the Vulcanization of Rubber

1941 ◽  
Vol 14 (4) ◽  
pp. 826-834
Author(s):  
B. S. Garvey ◽  
C. H. Alexander ◽  
F. E. Küng ◽  
D. E. Henderson
Keyword(s):  
Physical Properties ◽  
Vital Role ◽  
Mixed Composition ◽  
Manufacturing Operations ◽  
Vulcanized Rubber ◽  
Hydrocarbon Solvents ◽  
Original Shape ◽  
Before And After ◽  
The Difference

Abstract The vital role played by rubber in modern civilization is due in part to the physical properties displayed by soft vulcanized rubber in service and in part to the characteristics of unvulcanized milled rubber which make it amenable to manufacturing operations. Vulcanization of rubber is a change in condition usually induced by heating it with sulfur, and is best defined by contrasting the difference in physical properties: To illustrate, compare a mill-mixed composition before and after vulcanization. Before vulcanization it is easily pulled apart and, if considerably extended, shows little tendency to retract, although, under impact, the recovery or rebound is considerable. If heated it becomes even softer and more plastic, and can easily be formed into any desired shape. If cooled to 0° C or somewhat lower, it becomes stiff and boardy. It is readily soluble in hydrocarbon solvents. When two fresh surfaces are pressed together, they coalesce and become practically integral. This tack, as it is called, is valuable in manufacturing operations. After vulcanization, rubber is tough and strong and, after even a slow distortion, returns rapidly to its original shape. It has little tendency to flow and is devoid of tack. It swells but does not dissolve in hydrocarbon solvents. These characteristics change very little from −40° to well above 100° C.

Platelet Mechanosensing: Adhesion and Spreading On Immobilized Fibrinogen Depends On Substrate Stiffness

Blood ◽  
2012 ◽  
Vol 120 (21) ◽  
pp. 384-384
Author(s):  
Yongzhi Qiu ◽  
Ashley C Brown ◽  
Woo Jin Jung ◽  
Yumiko Sakurai ◽  
Robert Mannino ◽  
...  
Keyword(s):  
Physical Properties ◽  
Platelet Adhesion ◽  
The Body ◽  
Substrate Stiffness ◽  
Fibrinogen Concentration ◽  
Spreading Area ◽  
Significant Difference ◽  
The Difference ◽  
Underlying Substrate ◽  
Covalently Bound

Abstract Abstract 384 Background: Whereas surface-immobilized fibrinogen readily causes platelet adhesion and spreading, soluble fibrinogen, on the other hand, does not lead to platelet activation without the presence of other hemostatic/thrombotic signals. This dramatically different response of platelets to fibrinogen may be due to biochemical difference in fibrinogen unfolding (Agnihotri, et al., Langmuir, 2004), but may also be due to the difference in how platelets directly react to the physical properties of the substrate underneath the fibrinogen. Similarly, recent studies have shown that many types of adherent eukaryotic cells respond differently to substrates of different physical properties. In particular, cells are able to mechanosense the stiffness of their underlying substrate, and to change their spreading, re-organize their cytoskeleton, and even alter gene expression responding to the sensed stiffness (Discher, et al., Science, 2005). More specific to platelets, our group has recently shown that the contraction of single platelets on fibrinogen surfaces increases with increasing substrate stiffness (Lam, et al., Nat Mater, 2011). Therefore, we hypothesize that substrate stiffness can also affect platelet adhesion and spreading on fibrinogen. In this study, we synthesized polyacrylamide (PAA) gels, which can be tuned to different stiffnesses and easily modified with covalently-bound fibrinogen on the surface. This assay enables independent control of substrate stiffness while maintaining constant biochemical composition and fibrinogen density, and we applied this system to quantitatively investigate the role of substrate stiffness in platelet adhesion and spreading on fibrinogen. Results and Discussions: 3 μg/ml fibrinogen was covalently bound to the surface of PAA gels of different stiffnesses (0.25, 0.5, 2.5, 5, 50 and 100 kilopascals (KPa)) (Figure 1A). This applied range of substrate stiffness mimics the stiffness of different tissues in the body (Engler, et al., Cell, 2006). Moreover, glass (with a stiffness of ∼65–70 × 103 KPa) adsorbed with 3 μg/ml fibrinogen was also used for comparison. During 2 hour incubations, washed human platelets differently adhered to and spread on the surface of PAA gels. By simply varying the stiffness of the fibrinogen-bound PAA gels, we observed dramatic differences in the number of adherent platelets and their morphology (Figure 1B). The number of adherent platelets increased with increasing stiffness, reaching a plateau at 2.5 KPa, with adherence similar to that of fibrinogen-adsorbed glass (Figure 1C). While platelets did not spread on 2.5 KPa and softer gels, approximately 30–40% adherent platelets spread on 5KPa and stiffer gels, resulting in a significantly higher average spreading area of adherent platelets (Figure 1D and E). However, compared to all the gels, mostly all platelets adhered on glass surface spread (area > 35 μm2) and showed a significantly higher spreading area (Figure 1D and E). Moreover, no significant difference in fibrinogen concentration was detected among fibrinogen-bound PAA gels of different stiffnesses and fibrinogen-adsorbed glass (Data not shown), which indicated that the difference we observed could be independently due to the substrate stiffness. Conclusions and Ongoing Efforts: Our data suggest that platelets sense the mechanical properties of the underlying substrate to fine-tune the degree of adhesion and spreading on fibrinogen. Thus, fibrinogen on soft substrates appears to activate platelets to a lesser degree than the same concentration of fibrinogen on stiffer substrates. We are currently investigating how substrate stiffness triggers mechanotransduction in platelets and affects their outside-in activation and signaling. Our study also provides potential insights for preventing clot formation on implanted biomaterials and medical devices. Disclosures: No relevant conflicts of interest to declare.

Effects of Different Thermal Treatment Methods on Preparation and Physical Properties of High Amylose Maize Starch Based Films

2018 ◽  
Vol 14 (4) ◽  
Author(s):  
Yuyue Zhong ◽  
Xu Li ◽  
Tianru Lan ◽  
Yibo Li ◽  
Linsan Liu ◽  
...  
Keyword(s):  
Thermal Treatment ◽  
Physical Properties ◽  
Raw Material ◽  
Maize Starch ◽  
Solubility In Water ◽  
Treatment Methods ◽  
Starch Films ◽  
The Difference ◽  
High Amylose ◽  
Water Holding

AbstractBecause of its biodegradable trait, starch has been widely used as the raw material for packaging. Effects of different thermal treatment methods (high temperature-high pressure heating (HH), microwave heating (MH) and alkali heating (AH) with and without glycerol on physical properties of high amylose maize starch films (HASFs) were investigated in this study. HASFs under HH had highest elongation at break (E%), and lowest tensile strength (TS), modulus of elasticity (EM) and opacity (OC). HASFs under MH had highest TS, water holding capacity (WHC) and OC, and lowest thickness (TN), E%, solubility in water (SW) and solubility in oil (SO), while HASFs under AH had highest TN, EM, SW and SO, and lowest WHC. Compared with water, plasticized HASFs with glycerol had higher TN，E%, WHC, SW and OC, and lower TS, EM and SO. XRD results revealed the V-type polymorph and the difference in intensity of diffraction peaks of HASFs under three methods. This study would be helpful to design and prepare HASFs.

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