STUDIES IN THE POLYOXYPHENOL SERIES: V. PREPARATION FROM PYROGALLOL OF THE ISOMERIC CYCLOHEXANE-1,2,3-TRIOLS AND -1,2-DIOLS, AND OF SEVERAL ISOPROPYLIDENE AND MONOMETHYL DERIVATIVES

1951 ◽  
Vol 29 (11) ◽  
pp. 911-925 ◽  
Author(s):  
W. R. Christian ◽  
C. J. Gogek ◽  
C. B. Purves
Keyword(s):  
High Pressure ◽  
Hydrogen Chloride ◽  
Chromium Oxide ◽  
Palladium Catalysts ◽  
Minor Amount ◽  
Trans Form ◽  
Primary Products ◽  
Nickel Copper ◽  
First Time ◽  
Oil Formation

A study of the high pressure hydrogenation of pyrogallol over nickel, copper – chromium oxide, and palladium catalysts showed that yields of 35% to about 60% of cis-cis-cis-cyclohexane-l,2,3-triol were attainable, but that the cis-cis-trans and cis-trans-cis isomers were formed only in minor amount. Partial hydrogenolysis of these primary products incidentally yielded some cis-cyclohexane-l,2-diol, a smaller amount of the trans form, but none of the 1,3-diols. The following derivatives were prepared apparently for the first time: cis-cis-isopropylidene-cis-cyclohexane-l,2,3-triol, an oil, and its monobenzoate, m.p. 103 °C.; cis-cis-isopropylidene-trans-cyclohexane-l,2,3-triol, m.p. 51°C., and its monobenzoate, m.p. 72° to 76°C.; cis-monomethyl-cis-cis-cyclohexanetriol, m.p. 71°C., and its bis-3,5-dinitrobenzoate, m.p. 190°C.; trans-monomethyl-cis-cis-cyclohexane-l,2,3-triol, m.p. 37°C.;and isopropylidene-trans-cyclohexane-1,2-diol, an oil. Formation of the latter compound occurred when p-toluene-sulphonic acid, and not the customary hydrogen chloride, was used as catalyst in the condensation of the trans diol with acetone.

Fouling Is the Beginning: Upcycling Biopolymer-Fouled Substrates for Fabricating High-Permeance Thin-Film Composite Polyamide Membranes

2020 ◽  
Author(s):  
Ruobin Dai ◽  
Hongyi Han ◽  
Tianlin Wang ◽  
Jiayi Li ◽  
Chuyang Y. Tang ◽  
...  
Keyword(s):  
Thin Film ◽  
High Pressure ◽  
End Of Life ◽  
Water Purification ◽  
Low Pressure ◽  
Polymeric Membranes ◽  
Membrane Recycling ◽  
Film Composite ◽  
Thin Film Composite ◽  
First Time

Commercial polymeric membranes are generally recognized to have low sustainability as membranes need to be replaced and abandoned after reaching the end of their life. At present, only techniques for downcycling end-of-life high-pressure membranes are available. For the first time, this study paves the way for upcycling fouled/end-of-life low-pressure membranes to fabricate new high-pressure membranes for water purification, forming a closed eco-loop of membrane recycling with significantly improved sustainability.

scholarly journals Induction of Promoter DNA Methylation Upon High-Pressure Spraying of Double-Stranded RNA in Plants

Agronomy ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 789
Author(s):  
Athanasios Dalakouras ◽  
Ioannis Ganopoulos
Keyword(s):  
High Pressure ◽  
De Novo ◽  
Epigenetic Changes ◽  
Double Stranded Rna ◽  
Rna Molecules ◽  
Promoter Sequences ◽  
Promoter Dna Methylation ◽  
Promoter Dna ◽  
First Time ◽  
De Novo Methylation

Exogenous application of RNA molecules is a potent method to trigger RNA interference (RNAi) in plants in a transgene-free manner. So far, all exogenous RNAi (exo-RNAi) applications have aimed to trigger mRNA degradation of a given target. However, the issue of concomitant epigenetic changes was never addressed. Here, we report for the first time that high-pressure spraying of dsRNAs can trigger de novo methylation of promoter sequences in plants.

scholarly journals Influence of High Pressure on the Dimerization of ToxR, a Protein Involved in Bacterial Signal Transduction

2008 ◽  
Vol 74 (24) ◽  
pp. 7821-7823 ◽  
Author(s):  
Kai Linke ◽  
Nagarajan Periasamy ◽  
Matthias Ehrmann ◽  
Roland Winter ◽  
Rudi F. Vogel
Keyword(s):  
Escherichia Coli ◽  
Signal Transduction ◽  
High Pressure ◽  
Structure And Function ◽  
Transmembrane Segments ◽  
Bacterial Signal Transduction ◽  
Reporter Strains ◽  
And Function ◽  
First Time

ABSTRACT High hydrostatic pressure (HHP) is suggested to influence the structure and function of membranes and/or integrated proteins. We demonstrate for the first time HHP-induced dimer dissociation of membrane proteins in vivo with Vibrio cholerae ToxR variants in Escherichia coli reporter strains carrying ctx::lacZ fusions. Dimerization ceased at 20 to 50 MPa depending on the nature of the transmembrane segments rather than on changes in the ToxR lipid bilayer environment.

Research on Number of High-Pressure Grouting of Hierarchical Multiple for Slope Based on Reliability Analysis

2014 ◽  
Vol 716-717 ◽  
pp. 363-369
Author(s):  
Zhen Hua Xie ◽  
Dong Yang ◽  
Sha Sha Liang ◽  
Zhi Yun Jia
Keyword(s):  
High Pressure ◽  
Rock Mass ◽  
System Analysis ◽  
Rock Surface ◽  
Rock Permeability ◽  
Iron Mine ◽  
Probability Calculation ◽  
Before And After ◽  
Pressure Grouting ◽  
First Time

The technology of hierarchical multiple high-pressure grouting is an effective approach to manage high and steep slope of broken rock mass. The number of grouting is one of the key parameters of this technology. By the analysis of mechanics and grouting theory, the anchoring effect mainly is affected by anchor slurry vein and the contact area with rock mass. Based on the system analysis of slurry vein development for first time and many times high-pressure grouting, the process flow for hierarchical multiple high-pressure grouting is put forward. Serve the rock permeability changes before and after grouting as an indicator measuring slurry and rock surface area, the method of determining grouting number based on the reliable probability is got. Combined with the engineering example of Shouyun Iron Mine, this paper puts forward the reliability criteria of working state of hierarchical multiple high-pressure grouting. Through the probability calculation, the best number of grouting is 4 times. The tests of permeability of rock mass and drawing force verify the accuracy of this determination method.

High-pressure and high-temperature sintering of nanostructured bulk NiAl materials

2009 ◽  
Vol 24 (6) ◽  
pp. 2089-2096 ◽  
Author(s):  
Shanmin Wang ◽  
Duanwei He ◽  
Yongtao Zou ◽  
Jianjun Wei ◽  
Li Lei ◽  
...  
Keyword(s):  
High Pressure ◽  
Indentation Hardness ◽  
X Ray Diffraction ◽  
Temperature Dependent ◽  
High Pressure And Temperature ◽  
X Ray ◽  
High Pressure Sintering ◽  
Tentative Interpretation ◽  
Surface Shell ◽  
First Time

Nanostructured bulk NiAl materials were prepared at high pressure and temperature (0–5.0 GPa and 600–1500 °C, respectively). The sintered samples were characterized by x-ray diffraction, scanning electron microscope, density, and indentation hardness measurements. The results show that NiAl nanoparticles may have a compressed surface shell, which may be the reason why NiAl nanomaterials were difficult to densify sintering using conventional methods and why high-pressure sintering was an effective approach. We also observed that B2-structured NiAl could undergo a temperature-dependent phase transition and could be transformed into Al0.9Ni4.22 below 1000 °C for the first time. It is interesting to note that Vickers hardness decreased as grain size decreased below ∼30 nm, indicating that the inverse Hall-Petch effect may be observed in nano-polycrystalline NiAl (n-NiAl) samples. Moreover, a tentative interpretation was developed for high-pressure nanosintering, based on the shell-core model of nanoparticles.

Ternary Bio-Nanostructured Systems Prepared under High Pressure Conditions

2007 ◽  
Vol 361-363 ◽  
pp. 539-542 ◽  
Author(s):  
Roxana M. Piticescu ◽  
Viorica Trandafir ◽  
V. Danciu ◽  
Z. Vuluga ◽  
Eugeniu Vasile ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
High Pressure ◽  
Synthesis Method ◽  
Initial Mixture ◽  
Bone Defects ◽  
Metal Implants ◽  
Nanostructured Systems ◽  
Biological Performance ◽  
First Time ◽  
Hydroxyl Apatite

Many researchers have assumed that a combination of hydroxyl apatite (HAP) and collagen (COL) may be the best solution for bone replacement and have prepared their composites by several techniques [1]. However, such HAP/COL composite had no nanostructure similar to bone, and consequently indicated no bone-like mechanical properties. These results demonstrate that the chemical composition similar to bone only is insufficient for bone metabolism and mechanical properties. Mechanical and biological performance of this type of materials could be improved by adding TiO2 within the initial mixture of nanostructured composites [2]. Ternary nanostructured systems consisting of hydroxyl apatite, TiO2 aerogel and collagen were prepared for the first time by hydrothermal procedure in high pressure conditions. Among many advantages, the synthesis method proposed in this paper could lead to formation of chemically bonded compounds as a consequence of high pressure conditions. The resulted material could find applications in bone tissue regenerative medicine, either in powder form for bone defects treatment, or in matrix form as osteoconductive coating for metal implants. Further studies are necessary to evaluate the osteoconductive properties.

Some unusual complexes of iron with 1,10-phenanthroline and 2,2'-bipyridyl

1967 ◽  
Vol 20 (7) ◽  
pp. 1375 ◽  
Author(s):  
R Driver ◽  
WR Walker
Keyword(s):  
Trans Form ◽  
First Time ◽  
Derivatives Of ◽  
Red Form

The following hydroxy-bridged iron(III) complexes have been isolated for the first time : [phen2 Fe(OH)2Fe phen2](SO4)2,7H2O, [phen2 Fe(OH)2Fe phen2]Br4,2H2O, [bipy2 Fe(OH)2Fe bipy2](SO4)2,9H2O. Attempts to prepare thiocyanate derivatives of these complexes resulted unexpectedly in the synthesis of the compounds Fe(SCN)2 phen2,H2O and [FeSCN phen2]ClO4 which were investigated in the light of the well-known complexes of the type FeX2 chelate2. The compound [Fe phen3][Fe(CN)4 phen],5H2O which, except for water, has the same stoicheiometry as Fe(CN)4 phen2, is also described for the first time. The claim by Madeja (Chemicke Zvesti, 1965, 19, 186) that the compound Fe(SCN)2 bipy2 exists both as a red trans form (μeff 3.0 B.M.) and a violet cis form (μeff 5.2 B.M.) is not justified according to this work. It seems that the red form may be a mixture of the paramagnetic bis- and the diamagnetic tris-compounds.

scholarly journals Phosphorylation of the Oncofetal Variant of the Human Bile Salt-dependent Lipase

2001 ◽  
Vol 276 (15) ◽  
pp. 12356-12361 ◽  
Author(s):  
Alain Verine ◽  
Josette Le Petit-Thevenin ◽  
Laurence Panicot-Dubois ◽  
Annick Valette ◽  
Dominique Lombardo
Keyword(s):  
High Pressure ◽  
Bile Salt ◽  
Cho Cells ◽  
Phosphorylation Site ◽  
Chinese Hamster ◽  
Human Bile ◽  
Site Specific ◽  
Phosphorylation Motif ◽  
Extracellular Compartment ◽  
First Time

In this paper, we report, for the first time, the localization of the phosphorylation site of the fetoacinar pancreatic protein (FAPP), which is an oncofetal variant of the pancreatic bile salt-dependent lipase. Using Chinese hamster ovary (CHO) cells transfected with the cDNA encoding FAPP, we radiolabeled the enzyme with32P, and then the protein was purified by affinity chromatography on cholate-immobilized Sepharose column and submitted to a CNBr hydrolysis. Analysis of peptides by high pressure liquid chromatography, associated with the radioactivity profile, revealed that the phosphorylation site is located at threonine 340. Site-specific mutagenesis experiments, in which the threonine was replaced by an alanine residue, were used to invalidate the phosphorylation of FAPP and to study the influence of the modification on the activity and secretion of the enzyme. These studies showed that CHO cells, transfected with the mutated cDNA of FAPP, kept all of their ability to synthesize the protein, but the loss of the phosphorylation motif prevented the release of the protein in the extracellular compartment. However, the mutated enzyme, which was sequestrated in the transfected CHO cells, remains active on bile salt-dependent lipase substrates.

scholarly journals Interactions of Oxygen at High Pressure and Radiation in Drosophila

1966 ◽  
Vol 49 (3) ◽  
pp. 537-549 ◽  
Author(s):  
J.J. Thomas ◽  
R.C. Baxter ◽  
W.O. Fenn
Keyword(s):  
High Pressure ◽  
Life Span ◽  
Young Male ◽  
Fruit Fly ◽  
Young Female ◽  
Acute Effects ◽  
Irreversible Effects ◽  
X Irradiation ◽  
Effects Of Radiation ◽  
First Time

Oxygen at high pressure (OHP) and X-irradiation can interact in the fruit fly Drosophila melanogaster to potentiate toxic actions characteristic of one agent alone. 1000 kvp X-irradiation in doses of 30, 60, and 75 kr accelerated the acute immobilization of young male Drosophila by oxygen at 7.8 atm, up to rates twice that observed with such oxygen pressure alone. X-irradiation alone in these dosages did not acutely immobilize the Drosophila. X-irradiation during exposure to 7.8 atm pO2 was more effective and consistent in producing this potentiation than was X-irradiation that preceded exposure to OHP. Acute OHP toxicity in young female Drosophila was not potentiated by 75 kr of X-irradiation. On the other hand, shortening of the life span of young male Drosophila by the above doses of X-irradiation was augmented significantly by a concurrent 40 min exposure to OHP (which alone did not significantly decrease life span). This shows, for the first time, that oxygen can affect not only the acute effects of radiation, but also the residual irreversible effects indicated by the life span shortening.

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