The bicyclo[2.1.1]hexan-2-one system: a new probe for the experimental and computational study of electronic effects in π-facial selectivity in nucleophilic additions

The remotely substituted 5-exo-bicyclo[2.1.1]hexan-2-one system is introduced as a new probe to study long range electronic effects on π -face selectivity during hydride reduction and a systematic computational study demonstrates good predictability at the semi-empirical level

Root Vegetables Having Medicinal Properties: Their Possible Use in Pharmaceutical and Food Industries

Root, bulb, or tuber vegetables, which are borne underground, are reported to be dense in essential nutrients and come with several health benefits. Most of these root vegetables are the cultivated ones, but few are still underexploited. The root vegetables are consumed either wholly or partially and raw or after processing. They are high in fiber but low in fat and cholesterol. There are wide varieties of bioactive phytochemicals present in them that may contribute to their medicinal and nutraceutical properties. Although some research work has been conducted to uncover the pharmacological effects of root vegetables, their unlimited potential has yet to be fully exploited. The pharmaceutical industry can develop various health-promoting herbal formulations with medicinal properties. The food industry can employ novel processing technologies to preserve nutrition and prevent degradation of the phytochemicals during processing or for value addition of food products. The information presented in this chapter would be helpful for researchers, nutritional and medical professionals, pharmaceutical companies, and the food industry to design and develop effective medicines, drugs, and value-added food products by exploiting the specific as well as multiple modes of action of the various root vegetables

Preparation of Eu³⁺ doped Y₂O₃ and core-shell Y₂O₃:Eu-Y₂O₃ nanoparticles: Photoluminescence study

175-177 Nanocrystalline of Y2O3 doped with Eu3+ at different concentrations and also core-shell of Y2O3 is prepared by wet chemical method using urea hydrolysis at low temperatures. XRD, TEM and FTIR are used to characterize the prepared nanoparticles. The sizes determined by XRD are well in agreement with TEM results. As-prepared samples show luminescence peak of Eu3+ transition 5D0 → 7F2 at 615 nm but annealed samples at 610 nm. Core-shell study of the nanoparticles show reduction in the luminescence intensity compared to the core particles. </smarttagtype

Eu3+ as a marker for formation of core-shell system: YVO4:SiO2

Eu3+ doped in core and shell (YVO4:SiO2) nanoparticles show luminescence peaks corresponding to magnetic and electric dipole transitions of Eu3+. When Eu3+ ions occupy Y3+ sites, Eu3+ ions are surrounded by eight O2− ions, which is highly asymmetric (D2d). This asymmetric environment can be used to see amount of Eu3+ ions present in Y3+ sites. When Eu3+ ions are present in shell (SiO2), luminescence intensity is very weak. On further annealing, luminescence intensity increases due to diffusion of Eu3+ ions towards to YVO4 core through pores of SiO2. Distribution of Eu3+ in core and shell are supported by lifetime studies

Particle Size Effect on TL Emission of ZnS Nanoparticles and Determination of Its Kinetic Parameters

Nanoparticles have large surface area, and most of the ions are lying on its surface. Could these surface ions be contributed in thermoluminescence emission or enhanced nonradiative transition? In view of this, we have prepared small sizes of ZnS nanoparticles at low temperature and made two samples, one as-prepared (size ~3 nm) and the other heat-treated at 1073 K (size ~32 nm). Characterization of the samples shows that the prepared phosphors are pure. Thermoluminescence (TL) glow curves could not be recorded in both samples without irradiation. Even for higher dose of γ-radiation the as-prepared samples could not show TL signal, but 1073 K heat-treated sample shows the TL signal. This may be due to the fact that smaller particles have large surface area compared to bigger particles, the surface ions may produce the nonradiative transitions. The kinetic parameters of the TL glow curves are evaluated by the conventional methods and compared with curve fitting computerised glow curve deconvolution (CGCD) technique. The variations in both techniques are found only ±0.02. The shape factor of all the glow curves ~0.48, and these TL glow curves could be fitted with order of kinetics 1.5

Toward a total synthesis of the novel neurotrophic sesquiterpene merrilactone A: a RCM and [2+2]-photocycloaddition based approach to framework construction

A new strategy toward the total synthesis of the novel structural complex and biologically potent neurotrophic factor merrilactone A from 2,3-dimethyl-2-cyclopentene-1,4-dione is outlined. The approach involving RCM and [2+2]-photocycloaddition as the key steps, is notable for the orchestration of a series of regio- and stereoselective operations that lead to the core structural motif present in the sesquiterpenoid natural product

Toward a total synthesis of the novel neurotrophic sesquiterpene merrilactone A: a RCM and [2+2]-photocycloaddition based approach to framework construction

A new strategy toward the total synthesis of the novel structural complex and biologically potent neurotrophic factor merrilactone A from 2,3-dimethyl-2-cyclopentene-1,4-dione is outlined. The approach involving RCM and [2+2]-photocycloaddition as the key steps, is notable for the orchestration of a series of regio- and stercoselective operations that lead to the core structural motif present in the sesquiterpenoid natural product. (C) 2005 Elsevier Ltd. All rights reserved

ASSESSEMENT OF FACTORS AFFECTING SELF EMPLOYMENT IN DEBRE BERHAN CITY ADMINISTIRATION

The purpose of this study was to assess factors affecting self-employment in Debre Berhan City Administration; in particular, the study focuses on factors affecting the decision to be self-employed. The research used mixed design, to be covered by the survey; four kebeles were selected using simple random sampling methods. The required sample sizes of 302 were drawn from 4 kebeles. The data required for this study were obtained from primary and secondary sources. The primary data were collected from self-employed and Key Informants (KII) from Trade Industry and Marketing Development Department. The questionnaire had three parts, background information of the respondents, likert question and unstructured questions for the interview. The data were analyzed using descriptive statistics. The findings of the study showed that working premises, accesses to finance; motivation and training were critical problems. To alleviate the problems the study concluded by recommending the government body, financial institutions ,universities and colleges in providing appropriate working places, facilitating financial access, provision of training enhancing the intension of students towards self employment. Finally, the findings of this study could help the formulation of policies and strategies to facilitate and enhancing self-employment and reduction of unemployment in Debre Berhan City Administration