Anion recognition in water by a rotaxane containing a secondary rim functionalised cyclodextrin stoppered axle

2015 ◽  
Vol 51 (21) ◽  
pp. 4499-4502 ◽  
Author(s):  
Michal Řezanka ◽  
Matthew J. Langton ◽  
Paul D. Beer
Keyword(s):  
Pure Water ◽  
Anion Recognition ◽  
Water Soluble ◽  
Cyclodextrin Derivatives ◽  
Halide Anions

The synthesis of a water soluble [2]rotaxane is reported using hydrophilic secondary rim functionalised permethylated β-cyclodextrin derivatives as the axle stopper groups. The rotaxane recognises halide anions in pure water with impressive selectivity over sulfate.

scholarly journals Photo-transformation of aqueous nitroguanidine and 3-nitro-1,2,4-triazol-5-one : emerging munitions compounds

2021 ◽  
Author(s):  
Julie Becher ◽  
Samuel Beal ◽  
Susan Taylor ◽  
Katerina Dontsova ◽  
Dean Wilcox
Keyword(s):  
Aqueous Solutions ◽  
Degradation Products ◽  
Pure Water ◽  
Transformation Products ◽  
Water Soluble ◽  
Uv Exposure ◽  
Degradation Pathways ◽  
Solution Ph ◽  
Photo Degradation ◽  
Degradation Rates

Two major components of insensitive munition formulations, nitroguanidine (NQ) and 3-nitro-1,2,4-triazol-5-one (NTO), are highly water soluble and therefore likely to photo-transform while in solution in the environment. The ecotoxicities of NQ and NTO solutions are known to increase with UV exposure, but a detailed accounting of aqueous degradation rates, products, and pathways under different exposure wavelengths is currently lacking. We irradiated aqueous solutions of NQ and NTO over a 32-h period at three ultraviolet wavelengths and analyzed their degradation rates and transformation products. NQ was completely degraded by 30 min at 254 nm and by 4 h at 300 nm, but it was only 10% degraded after 32 h at 350 nm. Mass recoveries of NQ and its transformation products were >80% for all three wavelengths. NTO degradation was greatest at 300 nm with 3% remaining after 32 h, followed by 254 nm (7% remaining) and 350 nm (20% remaining). Mass recoveries of NTO and its transformation products were high for the first 8 h but decreased to 22–48% by 32 h. Environmental half-lives of NQ and NTO in pure water were estimated as 4 and 6 days, respectively. We propose photo-degradation pathways for NQ and NTO supported by observed and quantified degradation products and changes in solution pH.

scholarly journals Cyclopentadienone Iron Tricarbonyl Complexes-Catalyzed Hydrogen Transfer in Water

Molecules ◽  
2020 ◽  
Vol 25 (2) ◽  
pp. 421 ◽  
Author(s):  
Daouda Ndiaye ◽  
Sébastien Coufourier ◽  
Mbaye Diagne Mbaye ◽  
Sylvain Gaillard ◽  
Jean-Luc Renaud
Keyword(s):  
Metal Complexes ◽  
Hydrogen Transfer ◽  
Low Cost ◽  
Pure Water ◽  
Free Water ◽  
Water Soluble ◽  
Tricarbonyl Complex ◽  
Reaction Conditions ◽  
Catalytic Systems ◽  
Iron Tricarbonyl

The development of efficient and low-cost catalytic systems is important for the replacement of robust noble metal complexes. The synthesis and application of a stable, phosphine-free, water-soluble cyclopentadienone iron tricarbonyl complex in the reduction of polarized double bonds in pure water is reported. In the presence of cationic bifunctional iron complexes, a variety of alcohols and amines were prepared in good yields under mild reaction conditions.

scholarly journals Photochemical upconversion in water

2017 ◽  
Vol 53 (85) ◽  
pp. 11705-11708 ◽  
Author(s):  
Karim A. El Roz ◽  
Felix N. Castellano
Keyword(s):  
Charge Transfer ◽  
Pure Water ◽  
Water Soluble ◽  
Current Investigation ◽  
Ligand Charge Transfer

The current investigation achieves photochemical upconversion in pure water using combinations of water soluble Ru(ii) metal-to-ligand charge transfer (MLCT) sensitizers in concert with 9-anthracenecarboxylate (AnCO2−) and 1-pyrenecarboxylate (PyCO2−).

scholarly journals Preparation and Application of Bioshell Calcium Oxide (BiSCaO) Nanoparticle-Dispersions with Bactericidal Activity

Molecules ◽  
2019 ◽  
Vol 24 (18) ◽  
pp. 3415 ◽  
Author(s):  
Sato ◽  
Ishihara ◽  
Nakamura ◽  
Fukuda ◽  
Takayama ◽  
...  
Keyword(s):  
Calcium Oxide ◽  
Pure Water ◽  
Bacterial Flora ◽  
Particle Diameter ◽  
Average Diameter ◽  
Water Soluble ◽  
High Ph ◽  
Reduction Activity ◽  
Nanoparticle Dispersions ◽  
Alkaline Conditions

Scallop-shell powder (SSP) heated at high temperature exhibits high pH and broad antimicrobial activity. Bioshell calcium oxide (BiSCaO) is an SSP composed mainly of calcium oxide. It is poorly water-soluble under alkaline conditions and the generated precipitate can plug spray nozzles. The aim of this study was to establish that BiSCaO dispersion caused no significant CaO loss and plugging of spray nozzles, and to evaluate its deodorization and microbicidal abilities and its ability to reduce the concentrations of NO2− and NO3−. BiSCaO dispersions were prepared by mixing various concentrations of BiSCaO suspension, while phosphate compounds such as Na3PO4, Na2HPO4 or NaH2PO4 and the pH, average diameter, zeta potential, and form of the compounds with cryo-SEM were evaluated. We evaluated deodorization using tainted pork meat and microbicidal efficacy using contaminated suspension with normal bacterial flora. The concentration of NO2− and NO3− after mixing BiSCaO dispersion and pure water containing a high proportion of NO2− and NO3− were measured. BiSCaO dispersion formed with Na2HPO4, whose ratio to BiSCaO was 60%, showed a high pH (>12), a small particle diameter (>181 nm) and was stable for seven days. The BiSCaO dispersion showed higher deodorization and microbicidal activities than SSP-Ca(OH)2, which was mainly composed of Ca(OH)2. BiSCaO, but not SSP-Ca(OH)2, could reduce the concentration of NO2− and NO3− by more than 90% within 15 min. We developed a stable BiSCaO dispersion, and it had high deodorization and microbicidal efficacy. These activities of BiSCaO might result from the high pH caused by CaO hydration and a reduction activity causing active radical species.

scholarly journals Associated-Extraction Efficiency of Six Cyclodextrins on Various Flavonoids in Puerariae Lobatae Radix

Molecules ◽  
2018 ◽  
Vol 24 (1) ◽  
pp. 93 ◽  
Author(s):  
Tao Feng ◽  
Fan Liu ◽  
Lili Sun ◽  
Hongna Huo ◽  
Xiaoliang Ren ◽  
...  
Keyword(s):  
High Performance ◽  
Water Solubility ◽  
Extraction Efficiency ◽  
Cerebrovascular Diseases ◽  
Water Soluble ◽  
Cyclodextrin Derivatives ◽  
Treatment And Prevention ◽  
Promising Application ◽  
Sulfobutyl Ether ◽  
Processed Products

Puerariae Lobatae Radix (PLR), a well-known herbal medicine, is the root of Pueraria lobata (Willd.) Ohwi and has been employed for the treatment and prevention of cardiovascular and cerebrovascular diseases. The purpose of this study was to compare the associated-extraction efficiency of six cyclodextrins (CDs) on five flavonoids in PLR, namely puerarin, daidzein, daidzin, genistein and genistin, which are the major secondary metabolites, and exhibit low water solubility. The six CDs applied were β-cyclodextrin (β-CD), γ-cyclodextrin (γ-CD), hydroxypropyl-β-cyclodextrin (HP-β-CD), hydroxypropyl-γ-cyclodextrin (HP-γ-CD), carboxymethyl-β-cyclodextrin (CM-β-CD), and sulfobutyl ether β-cyclodextrin (SBE-β-CD). They can be grouped into one of the following three categories: traditional cyclodextrins (β-CD and γ-CD), water-soluble cyclodextrin derivatives (HP-β-CD and HP-γ-CD) and ionic cyclodextrin derivatives (SBE-β-CD and CM-β-CD). High-performance liquid chromatography (HPLC) was used to analyze the five flavonoids in the original aqueous extracts (OAE) in the presence or absence of various CDs. The associated-extraction efficiency of the various CDs followed the ranking: SBE-β-CD > HP-β-CD > CM-β-CD > HP-γ-CD > γ-CD > β-CD. It was clear that SBE-β-CD presented the highest associated-extraction capability, and it was used to extract the four flavonoids from three PLR products, including raw product, stir- fried product, and product simmered with wheat bran. The results showed that SBE-β-CD could improve the extraction capability of flavonoids, both from the raw product and in processed products of PLR. In conclusion, CDs, especially SBE-β-CD, have a promising application for the associated-extraction of flavonoids from PLR.

scholarly journals Hygroscopic properties of Amazonian biomass burning and European background HULIS and investigation of their effects on surface tension with two models linking H-TDMA to CCNC data

2010 ◽  
Vol 10 (12) ◽  
pp. 5625-5639 ◽  
Author(s):  
E. O. Fors ◽  
J. Rissler ◽  
A. Massling ◽  
B. Svenningsson ◽  
M. O. Andreae ◽  
...  
Keyword(s):  
Surface Tension ◽  
Biomass Burning ◽  
Organic Material ◽  
Inorganic Compounds ◽  
Pure Water ◽  
Condensation Nucleus ◽  
Water Soluble ◽  
Cloud Condensation Nucleus ◽  
Rural Site ◽  
Hygroscopic Properties

Abstract. HUmic-LIke Substances (HULIS) have been identified as major contributors to the organic carbon in atmospheric aerosol. The term "HULIS" is used to describe the organic material found in aerosol particles that resembles the humic organic material in rivers and sea water and in soils. In this study, two sets of filter samples from atmospheric aerosols were collected at different sites. One set of samples was collected at the K-puszta rural site in Hungary, about 80 km SE of Budapest, and a second was collected at a site in Rondônia, Amazonia, Brazil, during the Large-Scale Biosphere-Atmosphere Experiment in Amazonia – Smoke Aerosols, Clouds, Rainfall and Climate (LBA-SMOCC) biomass burning season experiment. HULIS were extracted from the samples and their hygroscopic properties were studied using a Hygroscopicity Tandem Differential Mobility Analyzer (H-TDMA) at relative humidity (RH) <100%, and a cloud condensation nucleus counter (CCNC) at RH >100%. The H-TDMA measurements were carried out at a dry diameter of 100 nm and for RH ranging from 30 to 98%. At 90% RH the HULIS samples showed diameter growth factors between 1.04 and 1.07, reaching values of 1.4 at 98% RH. The cloud nucleating properties of the two sets of aerosol samples were analysed using two types of thermal static cloud condensation nucleus counters. Two different parameterization models were applied to investigate the potential effect of HULIS surface activity, both yielding similar results. For the K-puszta winter HULIS sample, the surface tension at the point of activation was estimated to be lowered by between 34% (47.7 mN/m) and 31% (50.3 mN/m) for dry sizes between 50 and 120 nm in comparison to pure water. A moderate lowering was also observed for the entire water soluble aerosol sample, including both organic and inorganic compounds, where the surface tension was decreased by between 2% (71.2 mN/m) and 13% (63.3 mN/m).

Synthesis of water-soluble multidentate aminoalcohol β-cyclodextrin derivatives via epoxide opening

2011 ◽  
Vol 346 (17) ◽  
pp. 2677-2682 ◽  
Author(s):  
K. Martina ◽  
M. Caporaso ◽  
S. Tagliapietra ◽  
G. Heropoulos ◽  
O. Rosati ◽  
...  
Keyword(s):  
Water Soluble ◽  
Cyclodextrin Derivatives ◽  
Epoxide Opening

Water-soluble salen–Pd complex as an efficient catalyst for Suzuki–Miyaura reaction of sterically hindered substrates in pure water

Tetrahedron ◽  
2015 ◽  
Vol 71 (42) ◽  
pp. 7985-7989 ◽  
Author(s):  
Ya-shuai Liu ◽  
Ning-ning Gu ◽  
Ping Liu ◽  
Xiao-wei Ma ◽  
Yan Liu ◽  
...  
Keyword(s):  
Pure Water ◽  
Water Soluble ◽  
Efficient Catalyst ◽  
Sterically Hindered
Sign in / Sign up

Export Citation Format

Share Document