Enhanced Searchable Public Key Cipher Text With Hidden Structures For Fast Keyword Search

Existing semantically secure public-key searchable coding schemes take search time linear with the overall variety of the cipher texts. This makes retrieval from large-scale databases preventative. To alleviate this drawback, this paper proposes Searchable Public-Key Cipher texts with Hidden Structures (SPCHS) for keyword search as quick as potential while not sacrificing linguistics security of the encrypted keywords. In SPCHS, all keyword-searchable Cipher texts area unit structured by hidden relations, and with the search trapdoor such as a keyword, the minimum info of the relations is disclosed to an enquiry rule because the steering to search out all matching Cipher texts expeditiously. We have a tendency to construct a SPCHS theme from scratch during which the Cipher texts have a hidden star-like structure. We have a tendency to prove our theme to be semantically secure within the Random Oracle (RO) model. The search quality of our theme relies on the particular variety of the Cipher texts containing the queried keyword, instead of the amount of all Cipher texts. Finally, we have a tendency to gift a generic SPCHS construction from anonymous identity-based coding and collision-free full-identity malleable Identity-Based Key Encapsulation Mechanism (IBKEM) with namelessness. We have a tendency to illustrate 2 collision-free full-identity malleable IBKEM instances, that area unit semantically secure and anonymous, severally, within the artificial language and customary models

Synthesis and characterization of Polyindole and its catalytic performance study as a heterogeneous catalyst

The catalytic performance study of polyindole as a heterogeneous catalyst is reported for the synthesis of 3,3'-arylmethylene-bis-1H-Indole derivatives using various substituted aldehydes and indole under reflux reaction condition with good to excellent yield. Polyindole was synthesized by chemical oxidative polymerization using citric acid as a dopant. The synthesized polymer was well characterized by various spectroscopic techniques like FT-IR, XRD, FESEM, etc. The XRD pattern confirms the partially crystalline nature of polyindole. The FESEM images of polyindole revealed the formation of irregularly shaped particulate nature with size in the range of 0.2 to 6 micron. In FT-IR spectrum, the major peak at similar to 3400 cm(-1) indicates N-H stretching and at 1564-1624 cm(-1) indicates C-C stretching of benzenoid ring of indole. The presence of peak at similar to 3400 cm(-1) indicates that the polymerization does not occur at nitrogen. The present protocol has certain advantages like recyclability, low loading of the catalyst, low-cost and efficient use of polyindole as a heterogeneous catalyst

Biopolymer catalysed synthesis of 6-methyl-4-phenylcarbamoyl-1, 2, 3, 4-tetrahydropyrimidine-2-ones and evaluation of their anti-bacterial and anti-tubercular activities

1ackground: An efficient one-pot biocatalysed ultrasound assisted synthesis of dihydropyrimidinones/thiones has been developed under solvent free conditions. Materials and Methods: The use of biodegradable, non toxic, agar-powder as a catalyst provide advantages like high yield, simple operation, mild reaction condition with short reaction time. 1,2,3,4-tetrahydropyrimidine-2-ones/thiones formed were characterized by mass and 1H NMR spectroscopy. Results: The dihydropyrimidinones substituted with electron donating groups like fluorine, hydroxy along with thienyl groups exhibited good antibacterial activity. The compounds exhibited favorable binding interactions with mycobacterium target protein H37Rv. Conclusion: 4-methoxy substituted dihydropyrimidinones derivative showed significant antituberculosis activity

A Novel Enhancement of Nano Structure by Organic Acid Dopants in Emulsion Polymerization of Poly(o-toluidine)

A simple, more facile and green approach for the synthesis of poly(o-toluidine) (POT) has been described, by using oxidative emulsion polymn. in a heterogeneous phase by using ammonium persulfate as an oxidant and org. acids as dopant, acids used such as tartaric, oxalic and citric. The effect or influence of these dopants on cond., morphol. of the nano structure of POT and phys. properties are well studied and found that it depends on the nature and type of the functional org. acid dopants. By using this synthetic approach we have obtained POT nanostructures of uniform granular morphol., with av. 40-100 nm particle size doped with oxalic or citric acid, whereas in tartaric acid doped POT fibrilar morphol. with 40-60 nm size nano fibers was ascertained. These compds. were characterized by UV-Visible, FT-IR, SEM, and XRD. Elec. cond. studies of these materials were also carried out and found increase in cond. with citric acid and oxalic acid doped POT as compared to the tartaric acid. XRD studies showed partial cryst. nature of tartaric acid doped POT polymer as compared to others. By using this emulsion process, POT nanostructure formed with 60-100 nm diam. size having high yield, cond., and improved soly. in org. solvents in the emeraldine salt phase of polymer (confirmed by the presence of characteristic peaks at 420 nm and ~800-850 nm). The influences of reaction conditions, e.g. monomer, acid concn. on the physico-chem. properties were also investigated

Polyindole-ZnO Nanocomposite: Synthesis, Characterization and Heterogeneous Catalyst for the 3,4-Dihydropyrimidinone Synthesis under Solvent-free Conditions

<div><p>A Polyindole-ZnO nanocomposite particle was synthesized by using a chemical oxidative polymerization method. Synthesized nanocomposite was characterized by UV-Visible, FTIR, SEM, XRD, EDAX and electrical conductivity measurements. The band at ∼3400 cm⁻¹ and 735 cm⁻¹ in FTIR spectra confirmed the polyindole formation. XRD spectral studies exhibits major diffraction in between 30–40° (2θ) indicates the partial crystalline nature of the polyindole-ZnO nanocomposite. SEM image reveals agglomerated granular particulate nature with ZnO embedded in the polyindole matrix. The application of Polyindole-ZnO nanocomposite as a polymer-supported catalyst was studied for the synthesis of one pot multicomponent Biginelli condensation.</p> </div