Publications

1995
S. Ezrahi A. Aserin and N. Garti. 1995. Water-In-Oil-Microemulsion. United Kingdom 95/012 .
1994
N Garti, Aserin, A, and Ezrahi, S. 1994. An Attempt To Develop A New Fire-Resistant Hydraulic Fluid Based On Water-In-Oil Microemulsions.. Southern Brazilian Journal Of Chemistry, 2, 2, Pp. 83–104.
The strategy for the development of microemulsion-based fire-resistant hydraulic fluids was expounded. Phase diagrams were constructed for mixts. of water, oil and nonionic surfactants with and without cosurfactants. From these phase diagrams the boundaries of the monophasic area were outlined. After the major components had thus been detd., several preliminary formulations were developed by incorporating suitable additives into the oleic ingredient of the hydraulic fluid. The resulting microemulsion-based compns. complied with most of the requirements set for fire-resistant hydraulic fluids. Model systems pertinent to such formulations were utilized to investigate structural factors, which induce enhanced water solubilization. The role played by alcs. in this context was elucidated in terms of an empirical equation. Scattering and NMR methods have demonstrated the variations in the microstructure of a high water content model system. Sub-zero differential scanning calorimetry (DSC) techniques have revealed the existence of two types of water (free and bound) and detd. their relative concns. [on SciFinder(R)]
Nissim Garti, Kraus, David Joseph , Neidleman, Saul L, Pinthus, Eliezer J, and Pokora, Alexander R. 1994. Baking Improver/Dough Conditioner.. United States of America 297498 .
A dough conditioner is described wherein the dough conditioner is soybean peroxidase or an aq. ext. of soybean hulls. [on SciFinder(R)]
Shaw-Tao Lin, Wharry, Donald L, Yates, Robert L, Garti, Nissim , Pranata, Julianto , Siegel, Samuel , and Skrabal, Peter. . 1994. Catalytic Hydrogenation Of [2.2]Paracyclophane. Unsaturated Intermediates.. Journal Of Organic Chemistry, 59, 23, Pp. 7056–7060. doi:10.1021/jo00102a034.
The catalytic hydrogenation of [2.2]paracyclophane (1) was repeated to det. whether the claim that 1 yields an octahydro[2.2]paracyclophane (2) which contains a 1,4-cyclohexadienic structural unit can be substantiated. Decahydro[2.2]paracyclophane and three isomeric dienes as well as perhydroparacyclophane are isolated. The NMR spectra (1H and 13C) of the dienes are inconsistent with the earlier proposal, and the failure of the dienes to be aromatized by treatment with DDQ indicates that the trisubstituted double bonds reside in different six-membered rings. Computations of conformational energies aid the assignment of structures to the dienes. [on SciFinder(R)]
Y Feldman and Garti, N. 1994. Dielectric-Relaxation Phenomena Study By Time-Domain Dielectric-Spectroscopy. Abstracts Of Papers Of The American Chemical Society, 207, 2, Pp. 153–PMSE.
N Garti, Aserin, A, and Cohen, Y. 1994. Mechanistic Considerations On The Release Of Electrolytes From Multiple Emulsions Stabilized By Bsa And Nonionic Surfactants.. Journal Of Controlled Release, 29, 1-2, Pp. 41–51.
The stability of w/o/w emulsions has been significantly improved by using a blend of nonionic surfactant (Span 80) and bovine serum albumin (BSA) as an interfacial complex in the inner phase. Improved stability was obtained by replacing the common nonionic hydrophilic monomeric emulsifier by BSA in the outer phase. Optimum stability and droplet size of double emulsion was achieved with 0.2 wt% BSA + 10 wt% Span 80 as emulsifier I and 5.0 wt% Span 80-Tween 80 (2:3) or 0.1 wt% BSA as emulsifier II. Significant slow release of NaCl was obtained. The results were examd. in view of Higuchi mechanism and it was found that one can account for the thickness of the inner interfacial complex from the plot of B (diffusion parameter correlated to the fraction of electrolyte release) vs. time. It can be clearly seen that in the inner phase the surfactant and the BSA act synergistically (active interfacial complex), and enhance stability and reduce release. In the outer phase BSA has mainly a stabilizing effect with a limited release retardation effect. Effective diffusion coeffs. for each BSA concn. in the inner and outer phase have been calcd. and evaluated in a view of the diffusion controlled mechanism and the thickness of the viscoelastic film which is formed. [on SciFinder(R)]
Y SELA, MAGDASSI, S, and Garti, N. 1994. Newly Designed Polysiloxane-Graft-Poly (Oxyethylene) Copolymeric Surfactants: Preparation, Surface Activity And Emulsification Properties.. Colloid And Polymer Science, 272, 6, Pp. 684–691. doi:10.1007/BF00659282.
Two sets of comb-grafted polymeric surfactants based on poly(methylhydrogen siloxane) (PHMS) and/or poly(dimethylsiloxane) (PHMS-PDMS) were prepd. by silylation of the active Si-H group with an active $ømega$-vinyl group of specially designed undecenoic-polyethylene glycol esters (UPEG) to formation "newly-designed" polysiloxane-grafted-polyethylene glycol comb-copolymeric surfactants. The hydrophilic moieties are hooked to the hydrophobic backbone through a "spacer" (undecenoic acid). The variation in the surfactants' structures were in the length and d. of the grafted hydrophilic moieties, the chain length (DP) and nature of the hydrophobic backbone. The first 12 different polymeric surfactants (set 1), termed PHMS-UPEG, were ineffective emulsifiers with limited ability to stabilize oil-in-water emulsions. The second set of surfactants, named PHMS-PDMS-UPEG comb-grafted copolymers, significantly reduced the oil-water interfacial tension and efficiently stabilized several types of oil-in-water emulsions. The best emulsifier of this set (PHMS-PDMS-52-UPEG-45), seems to be one whose anchor backbone (PHMS-PDMS) dissolves (rather than spreads) in the oil phase, and whose stabilizing moieties are sufficiently long (45 EO units) and "hooked" to the silicone backbone at high d. (52% substitution). [on SciFinder(R)]
N. Garti and Smith, R. J. . 1994. Non-Stick Polymer-Coated Articles Of Manufacture, And Process And Coatings For The Production Thereof. United States of America 735-038 . doi:10.1533/9781845694210.1.107.
Y SELA, MAGDASSI, S, and Garti, N. 1994. Polymeric Surfactants Based On Polysiloxanes-Graft-Poly(Oxyethylene) For Stabilization Of Multiple Emulsions.. Colloids And Surfaces, A: Physicochemical And Engineering Aspects, 83, 2, Pp. 143–150. doi:10.1016/0927-7757(94)80097-9.
Attempts have been made to produce and use new polymeric surfactants based on polysiloxane-graft-poly(oxyethylene) for stabilization of water-in-oil-in-water (W/O/W) multiple emulsions. Hydrophobic comb-grafted copolymers have been used at the inner interface to obtain stable small droplet size water-in-oil emulsions. Hydrophilic comb-grafted copolymers with similar structures but with high d. grafting and long poly(oxyethylene) chains have been used to stabilize the outer interface of the W/O/W emulsion. Stable multiple emulsion formulations with very slow release rates can be obtained when using the two types of silicone emulsifier. [on SciFinder(R)]
Nissim Garti and Milhofer, Helga. . 1994. A Process For The Preparation Of Guar Derivatives. Israel 109983.
Nissim. Garti. 1994. Removal Of Cholesterol From Edibles. United States of America PCT/US 94/08814 .
S. Ezrahi A. Aserin and N. Garti. 1994. Water-In-Oil-Microemulsion. Israel 109893 .
N. Garti and Füredi-Milhofer, H.. 1994. Aspartame And Process For The Preparation Thereof. Israel 108907.
Helga Fueredi-Milhofer, Tunik, Leonid , Bloch, Raphael , and Garti, Nissim. . 1994. The Influence Of Surfactants On The Crystallization Of Calcium Oxalate Hydrates.. Molecular Crystals And Liquid Crystals Science And Technology, Section A: Molecular Crystals And Liquid Crystals, 248, Pp. 707–714.
The influence of SDS and octaethylene glycol mono-n-hexadecyl ether (I) on the crystn. of Ca oxalate from 0.3 M NaCl solns. is discussed. Under the given exptl. conditions the thermodynamically stable monohydrate (II) was the predominant crystal form. SDS inhibited growth and aggregation of II and, by preferential adsorption at different crystal faces, induced different habit modifications. In addn, micellar solns. of SDS promoted crystn. of the metastable calcium oxalate dihydrate. I stimulated nucleation and/or initial crystal growth of II, most probably by providing active centers for heterogeneous nucleation. [on SciFinder(R)]
H FurediMilhofer, Tunik, L, BLOCH, R, and Garti, N. 1994. The Influence Of Surfactants On The Crystallization Of Calcium-Oxalate Hydrates. Molecular Crystals And Liquid Crystals Science And Technology Section A-Molecular Crystals And Liquid Crystals, 248, Pp. 199–206. doi:10.1080/10587259408027180.
The influence of sodium dodecyl sulphate, SDS, dodecyl ammonium chloride, DDACl and octaethylene glycol mono-n-hexadecyl ether, C(16)EO(8), On the crystallization of calcium oxalate from 0.3 molar sodium chloride solutions is discussed. Under the given experimental conditions the thermodynamically stable monohydrate, COM was the predominant crystal form. Both ionic surfactants inhibited growth and aggregation of COM and, by preferential adsorption at different crystal faces, induced different habit modifications. In addition, micellar solutions of SDS promoted crystallization of the metastable calcium oxalate dihydrate, GOD. The nonionic surfactant, C(16)EO(8), Stimulated nucleation and/or initial crystal growth of COM, most probably by providing active centers for heterogeneous nucleation.
Nissim Garti and Reichman, Dov. . 1994. Surface Properties And Emulsification Activity Of Galactomannans.. Food Hydrocolloids, 8, 2, Pp. 155–173. doi:10.1016/S0268-005X(09)80041-6.
Galactomannans are considered to be predominantly hydrophilic carbohydrate polymers (gums) with a rigid backbone. The gums are not expected to have significant surface activity nor to form primary absorbed layers on oil-water interfaces. However, it was found that com., native BLG and guar gum reduce surface tension of water to ∼55 mN/m, and absorb/ppt. on oil-water interfaces, reducing their interfacial tensions. The surface activity of purified guar, where levels of proteins were reduced to a min. of 0.8% wt. was not inferior to that of the crude gum, unlike gum arabic. Oil-in-water emulsions of various oils with LBG or guar were prepd. The oil droplets were covered with pptd. gum layers exhibiting strong birefringency, indicating formation of organized gum layers on the interface. The adsorption capacity and surface load were evaluated. Coalescence and flocculation were minimized by establishing the best gum/oil ratios for full droplets coverage. [on SciFinder(R)]
I Nir, Feldman, Y, Aserin, A, and Garti, N. 1994. Surface Properties And Emulsification Behavior Of Denatured Soy Proteins.. Journal Of Food Science, 59, 3, Pp. 606–610. doi:10.1111/j.1365-2621.1994.tb05573.x.
Soy protein isolate was phys. (heat pretreatment) and chem. (urea, guanidine-HCl, and cleavage of SS bonds) modified in order to dissoc. subunits, unfold the protein, and improve surface properties: hydrophobicity, emulsification capability, and stability. Heat pretreatment as well as chem. treatment with urea or guanidine-HCl or redn. of disulfide bonds, will improve emulsification performance in comparison to native soy protein isolate. Significant differences in redn. of surface tension of water in the presence of native and modified proteins were obsd. (45 and 35 dynes/cm, resp.). Measurements of fluorescence indicated that the relative hydrophobicity of the soy protein was also improved (from 600 to 1360) after heat pretreatment or contacting the soy protein with an 8M urea soln. [on SciFinder(R)]
Yuri Feldman, Kozlovich, Nikolay , Nir, Ido , Aserin, Abraham , Ezrahi, Shmaryahu , and Garti, Nissim. . 1994. Time Domain Dielectric Study Of Non-Ionic Microemulsions.. Journal Of Non-Crystalline Solids, 172-174, Pt. 2, Pp. 1109–1116. doi:10.1016/0022-3093(94)90630-0.
The dielec. behavior of a microemulsion prepd. from dodecane, butanol, H2O and polyoxyethylene (10) oleyl alc. (Brij 97) was studied by time domain dielec. spectroscopy over the frequency range 105-1010 Hz for temps. between 10 and 40° with varying H2O content. Several dielec. dispersion regions with the typical characteristic relaxation times of the order of nanoseconds and tens of picoseconds are obsd. They are analyzed in time domain in terms of macroscopic dipole correlation functions and are attributed to the relaxation mechanisms of the different chem. compds. within the microemulsion. The appearance and intensity of the peaks for the relaxation processes depend on the H2O content. The types of motion of different kinetic units that can be manifested as local relaxation processes are proposed. The dielec. properties of microemulsions depend on the underlying phase behavior and on the consequent morphol. in these systems. The results suggest that changes in the microstructure of polarization and relaxation mechanisms occur in the H2O fraction content intervals of 5-10, 10-35, and 35%. [on SciFinder(R)]
1993
Yuri Feldman and Garti, Nissim. . 1993. Dielectric Relaxation Phenomena Study By Time Domain Dielectric Spectroscopy.. Polymeric Materials Science And Engineering, 70, Pp. 285–286.
The basic principles and promising potential of time domain dielec. spectroscopy in the investigation of inner and intermol. dynamics in macromol. systems are discussed. [on SciFinder(R)]
Nissim Garti, Rosano, Anat , and Avni, Yair. . 1993. Graft Copolymers As Emulsifiers. Part I. Grafted Polyethylene Glycol On Poly(Methyl Methacrylate).. Journal Of Dispersion Science And Technology, 14, 1, Pp. 47–70. doi:10.1080/01932699308943387.
Polymeric surfactants, based on grafted poly (ethylene glycol) (I) with different chain lengths on PMMA are prepd. and studied. The graft copolymer is prepd. by a transesterification reaction on the -OCOCH3 groups of the PMMA. The amphiphilic polymers reduce only slightly the H2O/air surface tension. However, interfacial tension of oil phases such as toluene are significantly reduced. The best polymeric surfactant, reducing interfacial tension practically to zero, is PMMA of mol. wt. 130,000 grafted with 6.5 wt% I consisting of 22 ethylene oxide units. Spontaneous emulsification is achieved with very low polymer concn. (\textless1.0%). Flocculation is obsd. in emulsion in which excess emulsifier is used or in systems contg. free ungrafted I. [on SciFinder(R)]

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