ChemInform Abstract: SYNTHESIS OF NEW PHOSPHORUS-CONTAINING HETEROCYCLES (REACTION OF BIFUNCTIONAL COMPOUNDS WITH DITHIOPHOSPHONIC ACID ANHYDRIDES)

1981 ◽  
Vol 12 (19) ◽  
Author(s):  
G. SALBECK
Keyword(s):  
Bifunctional Compounds ◽  
Phosphorus Containing ◽  
Acid Anhydrides ◽  
Dithiophosphonic Acid

Novel epoxy/anhydride alternatives for biological electron microscopy: Physical and performance characteristis of embed 812 and LX 112 in combination with NSA/NMA/DMAE

1989 ◽  
Vol 47 ◽  
pp. 1000-1001
Author(s):  
Joe A. Mascorro ◽  
Gerald S. Kirby
Keyword(s):  
Electron Microscopy ◽  
Flow Rate ◽  
Succinic Anhydride ◽  
Volume Flow Rate ◽  
Mass Density ◽  
Uranyl Acetate ◽  
Volume Flow ◽  
Base Resin ◽  
And Performance ◽  
Acid Anhydrides

Embedding media based upon an epoxy resin of choice and the acid anhydrides dodecenyl succinic anhydride (DDSA), nadic methyl anhydride (NMA), and catalyzed by the tertiary amine 2,4,6-Tri(dimethylaminomethyl) phenol (DMP-30) are widely used in biological electron microscopy. These media possess a viscosity character that can impair tissue infiltration, particularly if original Epon 812 is utilized as the base resin. Other resins that are considerably less viscous than Epon 812 now are available as replacements. Likewise, nonenyl succinic anhydride (NSA) and dimethylaminoethanol (DMAE) are more fluid than their counterparts DDSA and DMP- 30 commonly used in earlier formulations. This work utilizes novel epoxy and anhydride combinations in order to produce embedding media with desirable flow rate and viscosity parameters that, in turn, would allow the medium to optimally infiltrate tissues. Specifically, embeding media based on EmBed 812 or LX 112 with NSA (in place of DDSA) and DMAE (replacing DMP-30), with NMA remaining constant, are formulated and offered as alternatives for routine biological work.Individual epoxy resins (Table I) or complete embedding media (Tables II-III) were tested for flow rate and viscosity. The novel media were further examined for their ability to infilftrate tissues, polymerize, sectioning and staining character, as well as strength and stability to the electron beam and column vacuum. For physical comparisons, a volume (9 ml) of either resin or media was aspirated into a capillary viscocimeter oriented vertically. The material was then allowed to flow out freely under the influence of gravity and the flow time necessary for the volume to exit was recored (Col B,C; Tables). In addition, the volume flow rate (ml flowing/second; Col D, Tables) was measured. Viscosity (n) could then be determined by using the Hagen-Poiseville relation for laminar flow, n = c.p/Q, where c = a geometric constant from an instrument calibration with water, p = mass density, and Q = volume flow rate. Mass weight and density of the materials were determined as well (Col F,G; Tables). Infiltration schedules utilized were short (1/2 hr 1:1, 3 hrs full resin), intermediate (1/2 hr 1:1, 6 hrs full resin) , or long (1/2 hr 1:1, 6 hrs full resin) in total time. Polymerization schedules ranging from 15 hrs (overnight) through 24, 36, or 48 hrs were tested. Sections demonstrating gold interference colors were collected on unsupported 200- 300 mesh grids and stained sequentially with uranyl acetate and lead citrate.

MACHINERY OPERATIONAL PROPERTY CONTROL DURING DIAMOND-ABRASIVE FINISHING USING ACTIVE SOTS

2020 ◽  
Vol 2020 (9) ◽  
pp. 13-17
Author(s):  
Yuriy Ryzhov ◽  
Svetlana Abramova
Keyword(s):  
Corrosion Inhibitors ◽  
Tribological Behavior ◽  
Surface Layers ◽  
Physical Chemical ◽  
Abrasive Finishing ◽  
Alloying Additives ◽  
Phosphorus Containing ◽  
Micro Emulsion ◽  
Property Control ◽  
Diamond Abrasive

There is carried out a number of experiments with the purpose of analyzing SOTS impact upon both finishing productivity, and physical-chemical state and tribological behavior of surfaces machined, and also a possibility for creation according to the results of the investigations carried out a relatively universal micro-emulsion SOTS based on existing in the Ukraine the line of oils, PAV, corrosion inhibitors, alloying additives etc. As SOTS samples there were used both well-known compouds, for example, Camix, Nope Right (USA), and carbamide having in its structure boron, boron-phosphorus-containing additive, water-solvable phosphate, tributyl phosphate (oil-solvable), concentrate SOTS tribol, having in its structure compounds of boron, nitrogen and phosphorous; ethylic ether of fatty acids; methyl ether of colza oil; Sarkozyl-O having in its structure easily-decomposable chlorine compounds. From the results obtained it is possible to draw a conclusion that during finishing in the environment of water-compatible SOTS an important role in the formation of the properties of the surface worked is played by hydrocarbon components and additives which contribute to the formation of the thinnest surface layers modified with carbon and oxygen.

Validation of a Generation 4 Phosphorus-Containing Polycationic Dendrimer for Gene Delivery Against HIV-1

2012 ◽  
Vol 19 (29) ◽  
pp. 5044-5051 ◽  
Author(s):  
V. Briz ◽  
M.J. Serramia ◽  
R. Madrid ◽  
A. Hameau ◽  
Anne-Marie Caminade ◽  
...  
Keyword(s):  
Gene Delivery ◽  
Phosphorus Containing ◽  
Hiv 1

A Review on Current Synthetic Strategies of Oxazines

2018 ◽  
Vol 16 (1) ◽  
pp. 43-58 ◽  
Author(s):  
Santosh L. Gaonkar ◽  
Vignesh U. Nagaraj ◽  
Swarnagowri Nayak
Keyword(s):  
Biological Properties ◽  
The Past ◽  
Bifunctional Compounds ◽  
Synthetic Approaches ◽  
Oxazine Derivatives

In the past three decades, the heterocyclic oxazine cores have been intensely concerned. Oxazine derivatives are promising vital heterocyclic motifs. They are eminent for their synthetic potential and extensive biological properties. Oxazines are versatile intermediates for the synthesis of a variety of heterocycles and bifunctional compounds. Researchers have reported several synthetic approaches for the preparation of oxazines. This review emphasises the recent approaches for the synthesis of oxazine derivatives.

scholarly journals The Preparation, Thermal Properties, and Fire Property of a Phosphorus-Containing Flame-Retardant Styrene Copolymer

Materials ◽  
2019 ◽  
Vol 13 (1) ◽  
pp. 127 ◽  
Author(s):  
Yu Sun ◽  
Yazhen Wang ◽  
Li Liu ◽  
Tianyuan Xiao
Keyword(s):  
Thermal Properties ◽  
Thermogravimetric Analysis ◽  
Flame Retardant ◽  
Oxygen Index ◽  
Limiting Oxygen Index ◽  
Chemical Structures ◽  
1H Nuclear Magnetic Resonance ◽  
Phosphorus Containing ◽  
Ft Ir ◽  
Ft Ir Spectroscopy

A 9,10-dihydro-9-oxa-10-phosphaphenanthrene 10-oxide (DOPO) acrylate, (6-oxidodibenzo [c,e][1,2] oxaphosphinin-6-yl) methyl acrylate (DOPOAA), has been prepared. Copolymers of styrene (St) and DOPOAA were prepared by emulsion polymerization. The chemical structures of copolymers containing levels of DOPOAA were verified using Fourier transform infrared (FT-IR) spectroscopy and 1H nuclear magnetic resonance (1H-NMR) spectroscopy. The thermal properties and flame-retardant behaviors of DOPO-containing monomers and copolymers were observed using thermogravimetric analysis and micro calorimetry tests. From thermogravimetric analysis (TGA), it was found out that the T5% for decomposition of the copolymer was lower than that of polystyrene (PS), but the residue at 700 °C was higher than that of PS. The results from micro calorimetry (MCC) tests indicated that the rate for the heat release of the copolymer combustion was lower than that for PS. The limiting oxygen index (LOI) for combustion of the copolymer rose with increasing levels of DOPOAA. These data indicate that copolymerization of the phosphorus-containing flame-retardant monomer, DOPOAA, into a PS segment can effectively improve the thermal stability and flame retardancy of the copolymer.

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