This Review describes the application of nitroxides to synthesis and polymer chemistry. The synthesis and physical properties of nitroxides are discussed first. The largest section focuses on their application as stoichiometric and catalytic oxidants in organic synthesis. The oxidation of alcohols and carbanions, as well as oxidative C-C bond-forming reactions are presented along with other typical oxidative transformations. A section is also dedicated to the extensive use of nitroxides as trapping reagents for C-centered radicals in radical chemistry. Alkoxyamines derived from nitroxides are shown to be highly useful precursors of C-centered radicals in synthesis and also in polymer chemistry. The last section discusses the basics of nitroxide-mediated radical polymerization (NMP) and also highlights new developments in the synthesis of complex polymer architectures.

Nitroxides: applications in synthesis and in polymer chemistry.

Recent advances in copper-catalyzed oxidation of organic compounds

Selective oxidation of sulfides to sulfoxides and sulfones at room temperature using H2O2 and a Mo(VI) salt as catalyst

We report a mild and efficient electrochemical protocol to access a variety of vicinally C–O and C–N difunctionalized compounds from simple alkenes. Detailed mechanistic studies revealed a distinct reaction pathway from those previously reported for TEMPO-mediated reactions. In this mechanism, electrochemically generated oxoammonium ion facilitates the formation of azidyl radical via a charge-transfer complex with azide, TEMPO–N3. DFT calculations together with spectroscopic characterization provided a tentative structural assignment of this charge-transfer complex. Kinetic and kinetic isotopic effect studies revealed that reversible dissociation of TEMPO–N3 into TEMPO• and azidyl precedes the addition of these radicals across the alkene in the rate-determining step. The resulting azidooxygenated product could then be easily manipulated for further synthetic elaborations. The discovery of this new reaction pathway mediated by the TEMPO+/TEMPO• redox couple may expand the scope of aminoxyl radical chemistr...

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Electrochemical Azidooxygenation of Alkenes Mediated by a TEMPO-N3 Charge-Transfer Complex.

Copper(II) catalyzed selective oxidation of primary alcohols to aldehydes with atmospheric oxygen

L ow-Energy Adaptive Clustering Hierarchy (LEACH) is one of the most popular distributed cluster-based routing protocols in wireless sensor networks. Clustering algorithm of the LEACH is simple but offers no guarantee about even distribution of cluster heads over the network. LEACH doesn’t ensure even node-distribution among the clusters formed as per its provision. In this paper, we propose a New Clustering Scheme; the scheme must be designed to be extremely energy-efficient. Here the proposed scheme, a novel scheme, is supposed to achieve objective of being energy-efficient. In this paper, the modifications proposed in the existing scheme of LEACH which are assumed to improve the energy efficiency of the WSN.Furthermore, the scheme would be compared with LEACH to judge its relative performance over LEACH.

A Novel Static Clustering Scheme for Energy-efficient Routing in Wireless Sensor Network

- Internet of Things (IoT) Based Air Pollution Monitoring System is used to monitor the Air Quality over a web server using Internet. It will trigger an alarm when the air quality goes down beyond a certain level, means when there is sufficient amount of harmful gases present in the air like CO2, smoke, alcohol, benzene, NH3 and NOx.Pollution deaths are growing every year, and air pollutants is the primary contributor to those deaths. Occasionally, emission levels have risen due to several causes, such as the rise in population, increased use of automobiles, industrialization and urbanisation, which have a significant influence on the wellbeing of the people. To observe the situation this work includes anair pollution monitoring system which is an Internet of things using sensors based system,where we track quality of air through a web server on the Internet and generate warning about the air quality goes above a firm threshold, it implies when sufficient hazardous gas is present in the air such as benzene, NH3, smoke, CO2 and alcohol.The growth of business and Speedy human population urbanisation has horribleimpactupon worldwide air condition. in long-time period exposure to air pollution cause chronic heart and lung diseases, dangerously affecting human health. Thousands of factories and billions of cars launch large quantities of pollution into the air each day. so, tracking the air pollution has come to be important. In this paper, the development of an Internet of Things based air quality monitoring platform is presented and analize the performance of air quality monitoring system.

Air Pollution Quality Monitoring System Using Internet of Things for Smart Cities

In Wireless Sensor networks, on demand direction-finding procedures show an actual significant part for announcement among sensor knots using WSNs Protocol stack. This paper presents substantial study and analysis of WSNs protocol Stack using Bellman-Ford direction-finding procedure to pattern the flow of statistics among the layers. In this broadside we compare the existing on-demand direction-finding protocols like AODV, DSR, DYMO, FSR, IARP are made on the base of concert environments- throughput (bits/s) and normal end to end delay(s) in order to find the Quality of Service routing which can meet requirement of users in WSNs. The result shows that AODV satisfies QoS requirement as the numbers of packet transmitted in a given time is more as compared to others routing protocols.

Comparative Learning of on Request Direction-Finding Procedures in WSNs

Energy effectiveness is the chief limitation of Wireless Sensor Network because respectively device node in Wireless Sensor network has incomplete energy-efficiency and further limited resources. Cross layer design method allows straight announcement between procedure stack layers. Growth of cross-layer design method is greatest significant for enhancement excellence of facility corresponding energy-efficiency, scheme quantity and Normal end-to-end suspension of sensor nodes in WSNs. Therefore our emphasis is to expand the QoS of sensors nodes in WSNs. One of the methods to increase QoS is cross layer design technique in Wireless sensor network. QoS is compulsory on completely the coatings of wireless sensor network procedure heap nevertheless maximum effort emphasis individual on enhancing solitary coating in rapports of vitality ingesting for wireless sensor network. In this paper we recommend a CLD method which improves vitality depletion of the sensor nodes at the Network Layer, Data Link Layer and Physical Layers of the wireless protocol mountain since energy ingesting issues and others QoS issues happen in these three layers.

Rakesh Kumar Saini

Papers

A Novel Static Clustering Scheme for Energy-efficient Routing in Wireless Sensor Network

Air Pollution Quality Monitoring System Using Internet of Things for Smart Cities

Comparative Learning of on Request Direction-Finding Procedures in WSNs

Improve energy-efficiency of sensors using cross-layer design technique in WSNs