scholarly journals One-Step Methylation of Aromatic Phosphorus Heterocycles: Synthesis and Crystallographic Characterization of a 1-Methyl-Phosphininium Salt

2021 ◽  
Author(s):  
Lukas Fischer ◽  
Friedrich Wossidlo ◽  
Daniel Frost ◽  
Nathan Thomas Coles ◽  
Simon Steinhauer ◽  
...  
Keyword(s):  
Direct Synthesis ◽  
One Step ◽  
Phosphorus Heterocycles ◽  
First Time

For the first time the direct synthesis of 1-methyl-phosphininium salts has been achieved by reacting aromatic λ3,σ2-phosphinines with the readily available dimethyl chloronium salt [(CH3)2Cl]+[Al(OTeF5)4]-. The remarkably high electrophilicity of...

Synthesis and characterization of single-crystalline Bi2O2SiO3 nanosheets with exposed {001} facets

2017 ◽  
Vol 7 (17) ◽  
pp. 3791-3801 ◽  
Author(s):  
Shuoping Ding ◽  
Xuyang Xiong ◽  
Xiufan Liu ◽  
Yiqiu Shi ◽  
Qingqing Jiang ◽  
...  
Keyword(s):  
Hydrothermal Method ◽  
Bismuth Oxide ◽  
Synthesis And Characterization ◽  
Single Crystalline ◽  
One Step ◽  
First Time

Bismuth oxide silicate (Bi2O2SiO3) single-crystalline nanosheets with exposed {001} facets were synthesized for the first time via a facile one-step CTAB-assisted hydrothermal method in the presence of NaOH.

scholarly journals Direct Synthesis and Characterization of Photo-Crosslinkable Biodegradable PLA-PEG-PLA Ttiblock Copolymer with Methacrylates Functions by Green Montmorillonite Clay Catalyst

2020 ◽  
Vol 14 (4) ◽  
pp. 474-480
Author(s):  
Mohamed Benachour ◽  
◽  
Aslya El-Kebir ◽  
Amine Harrane ◽  
Rachid Meghabar ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Cationic Polymerization ◽  
Direct Synthesis ◽  
Average Molecular Weight ◽  
Montmorillonite Clay ◽  
Synthesis And Characterization ◽  
Molecular Weights ◽  
One Step ◽  
Clay Catalyst

Di-methacrylated PLA-PEG-PLA triblock copolymers of polylactide and polyethylene glycol were synthesized in one-step process by bulk cationic polymerization of lactide in the presence of PEG with different average molecular weights, using Maghnite-H+, an acidic montmorillonite clay, as a solid non-toxic catalyst. The obtained di-methacrylated copolymer was analyzed by 1H NMR and DSC. The effect of Maghnite-H+ proportions and PEG average molecular weight on the copolymerization and methacrylation yields and on average molecular weight of the resulting copolymers was studied.

scholarly journals Comparative studies of four monoclonal antibodies to phenylalanine hydroxylase exhibiting different properties with respect to substrate-dependence, species-specificity and a range of effects on enzyme activity

1981 ◽  
Vol 199 (3) ◽  
pp. 527-535 ◽  
Author(s):  
K H Choo ◽  
I G Jennings ◽  
R G H Cotton
Keyword(s):  
Enzyme Activity ◽  
Monoclonal Antibodies ◽  
Comparative Studies ◽  
Phenylalanine Hydroxylase ◽  
The Other ◽  
Preliminary Characterization ◽  
Substrate Dependence ◽  
One Step ◽  
First Time

Four monoclonal antibodies to phenylalanine hydroxylase are described. Two are inhibitory (PH alpha 1-1 and PH alpha 2-1-1 antibodies), one is stimulatory (B5-1 antibody) and one has no effect on enzyme activity (PH alpha 3-0 antibody). Their properties are compared. Two antibodies (PH alpha 1-1 and B5-1 antibodies) bind primate and rodent phenylalanine hydroxylase, whereas the other two (PH alpha 2-1-1 and PH alpha 3-0 antibodies) bind only the primate enzyme. The binding of PH alpha 1-1 antibody to phenylalanine hydroxylase is dependent on substrate phenylalanine, whereas the binding of the others is not influenced by phenylalanine. Affinity adsorbents prepared from the four antibodies purified phenylalanine hydroxylase substantially (greater than 80% purity) in one step, except for a PH alpha 3-0 antibody--Sepharose column, which behaved anomalously. Two previous publications described the isolation and preliminary characterization of B5 and PH alpha 1-1 antibodies. PH alpha 2-1-1 and PH alpha 3-0 antibodies are reported for the first time.

TBE in Sweden

2020 ◽  
Keyword(s):  
Genetic Characterization ◽  
Immunoglobulin M ◽  
Enzyme Linked Immunosorbent Assay ◽  
Second Phase ◽  
Serum Samples ◽  
Tick Borne Encephalitis ◽  
Specific Immunoglobulin ◽  
Tick Borne Encephalitis Virus ◽  
First Time

Tick-borne encephalitis virus (TBEV) was isolated for the first time in Sweden in 1958 (from ticks and from 1 tick-borne encephalitis [TBE] patient).1 In 2003, Haglund and colleagues reported the isolation and antigenic and genetic characterization of 14 TBEV strains from Swedish patients (samples collected 1991–1994).2 The first serum sample, from which TBEV was isolated, was obtained 2–10 days after onset of disease and found to be negative for anti-TBEV immunoglobulin M (IgM) by enzyme-linked immunosorbent assay (ELISA), whereas TBEV-specific IgM (and TBEV-specific immunoglobulin G/cerebrospinal fluid [IgG/CSF] activity) was demonstrated in later serum samples taken during the second phase of the disease.

Chemical Constituents and Antibacterial Activity of Cissus Aralioides.

2020 ◽  
Vol 17 ◽  
Author(s):  
Balogun Olaoye Solomon ◽  
Ajayi Olukayode Solomon ◽  
Owolabi Temitayo Abidemi ◽  
Oladimeji Abdulkarbir Oladele ◽  
Liu Zhiqiang
Keyword(s):  
Plant Extract ◽  
Chemical Constituents ◽  
Ethyl Acetate Fraction ◽  
Antibacterial Activities ◽  
Sub Saharan Africa ◽  
Chromatographic Purification ◽  
Whole Plant ◽  
Sub Saharan ◽  
First Time

: Cissus aralioides is a medicinal plant used in sub-Saharan Africa for treatment of infectious diseases; however the chemical constituents of the plant have not been investigated. Thus, in this study, attempt was made at identifying predominant phytochemical constituents of the plant through chromatographic purification and silylation of the plant extract, and subsequent characterization using spectroscopic and GC-MS techniques. The minimum inhibitory concentration (MICs) for the antibacterial activities of the plant extract, chromatographic fractions and isolated compounds were also examined. Chromatographic purification of the ethyl acetate fraction from the whole plant afforded three compounds: β-sitosterol (1), stigmasterol (2) and friedelin (3). The phytosterols (1 and 2) were obtained together as a mixture. The GC-MS analysis of silylated extract indicated alcohols, fatty acids and sugars as predominant classes, with composition of 24.62, 36.90 and 26.52% respectively. Results of MICs indicated that friedelin and other chromatographic fractions had values (0.0626-1.0 mg/mL) comparable with the standard antibiotics used. Characterization of natural products from C. aralioides is being reported for the first time in this study.

Green Synthesis and Spectroscopic Studies of Ag-rGO Nanocomposites for Highly Selective Mercury (II) Sensing

2018 ◽  
Vol 9 (1) ◽  
pp. 101-108 ◽  
Author(s):  
Shubhangi J. Mane-Gavade ◽  
Sandip R. Sabale ◽  
Xiao-Ying Yu ◽  
Gurunath H. Nikam ◽  
Bhaskar V. Tamhankar
Keyword(s):  
Green Synthesis ◽  
Color Change ◽  
Limit Of Detection ◽  
Aqueous Media ◽  
Suitable Condition ◽  
Cost Effective ◽  
Spectroscopic Studies ◽  
Calibration Plot ◽  
First Time

Introduction: Herein we report the green synthesis and characterization of silverreduced graphene oxide nanocomposites (Ag-rGO) using Acacia nilotica gum for the first time. Experimental: We demonstrate the Hg2+ ions sensing ability of the Ag-rGO nanocomposites form aqueous medium. The developed colorimetric sensor method is simple, fast and selective for the detection of Hg2+ ions in aqueous media in presence of other associated ions. A significant color change was noticed with naked eye upon Hg2+ addition. The color change was not observed for cations including Sr2+, Ni2+, Cd2+, Pb2+, Mg2+, Ca2+, Fe2+, Ba2+ and Mn2+indicating that only Hg2+ shows a strong interaction with Ag-rGO nanocomposites. Under the most suitable condition, the calibration plot (A0-A) against concentration of Hg2+ was linear in the range of 0.1-1.0 ppm with a correlation coefficient (R2) value 0.9998. Results & Conclusion The concentration of Hg2+ was quantitatively determined with the Limit of Detection (LOD) of 0.85 ppm. Also, this method shows excellent selectivity towards Hg2+ over nine other cations tested. Moreover, the method offers a new cost effective, rapid and simple approach for the detection of Hg2+ in water samples.

scholarly journals Waste-Based One-Part Alkali Activated Materials

Materials ◽  
2021 ◽  
Vol 14 (11) ◽  
pp. 2911
Author(s):  
Margarida Gonçalves ◽  
Inês Silveirinha Vilarinho ◽  
Marinélia Capela ◽  
Ana Caetano ◽  
Rui Miguel Novais ◽  
...  
Keyword(s):  
Compressive Strength ◽  
Microstructural Analysis ◽  
Construction Materials ◽  
Sodium Metasilicate ◽  
High Compressive Strength ◽  
Hardened State ◽  
First Time ◽  
Furnace Slag ◽  
Alkali Activated

Ordinary Portland Cement is the most widely used binder in the construction sector; however, a very high carbon footprint is associated with its production process. Consequently, more sustainable alternative construction materials are being investigated, namely, one-part alkali activated materials (AAMs). In this work, waste-based one-part AAMs binders were developed using only a blast furnace slag, as the solid precursor, and sodium metasilicate, as the solid activator. For the first time, mortars in which the commercial sand was replaced by two exhausted sands from biomass boilers (CA and CT) were developed. Firstly, the characterization of the slag and sands (aggregates) was performed. After, the AAMs fresh and hardened state properties were evaluated, being the characterization complemented by FTIR and microstructural analysis. The binder and the mortars prepared with commercial sand presented high compressive strength values after 28 days of curing-56 MPa and 79 MPa, respectively. The mortars developed with exhausted sands exhibit outstanding compressive strength values, 86 and 70 MPa for CT and CA, respectively, and the other material’s properties were not affected. Consequently, this work proved that high compressive strength waste-based one-part AAMs mortars can be produced and that it is feasible to use another waste as aggregate in the mortar’s formulations: the exhausted sands from biomass boilers.

Direct Synthesis and Characterization of Copper(II) 1‐Phenyltetrazol‐5‐olates

2021 ◽  
Author(s):  
Sergei Voitekhovich ◽  
Alexander Lyakhov ◽  
Ludmila Ivashkevich ◽  
Alexander Lavrov ◽  
Ludmila Lavrenova ◽  
...  
Keyword(s):  
Direct Synthesis ◽  
Synthesis And Characterization

scholarly journals Isolation and characterization of a new cold-active protease from psychrotrophic bacteria of Western Himalayan glacial soil

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Saleem Farooq ◽  
Ruqeya Nazir ◽  
Shabir Ahmad Ganai ◽  
Bashir Ahmad Ganai
Keyword(s):  
Specific Activity ◽  
Temperature Range ◽  
Psychrotrophic Bacteria ◽  
Isolation And Characterization ◽  
Cold Active ◽  
Active Protease ◽  
Quantitative Screening ◽  
First Time ◽  
Low K

AbstractAs an approach to the exploration of cold-active enzymes, in this study, we isolated a cold-active protease produced by psychrotrophic bacteria from glacial soils of Thajwas Glacier, Himalayas. The isolated strain BO1, identified as Bacillus pumilus, grew well within a temperature range of 4–30 °C. After its qualitative and quantitative screening, the cold-active protease (Apr-BO1) was purified. The Apr-BO1 had a molecular mass of 38 kDa and showed maximum (37.02 U/mg) specific activity at 20 °C, with casein as substrate. It was stable and active between the temperature range of 5–35 °C and pH 6.0–12.0, with an optimum temperature of 20 °C at pH 9.0. The Apr-BO1 had low Km value of 1.0 mg/ml and Vmax 10.0 µmol/ml/min. Moreover, it displayed better tolerance to organic solvents, surfactants, metal ions and reducing agents than most alkaline proteases. The results exhibited that it effectively removed the stains even in a cold wash and could be considered a decent detergent additive. Furthermore, through protein modelling, the structure of this protease was generated from template, subtilisin E of Bacillus subtilis (PDB ID: 3WHI), and different methods checked its quality. For the first time, this study reported the protein sequence for psychrotrophic Apr-BO1 and brought forth its novelty among other cold-active proteases.

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