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One-pot synthesis of spiroglycol
Jun Ming Xu, Fu Sheng Liu, Shi Tao Yu
Bulletin of the Chemical Society of Ethiopia , 2008,
Abstract: The synthesis of spiroglycol by one-pot reaction was studied using pentaerythritol, isobutyraldehyde and formaldehyde as starting materials. Under the optimum reacting conditions, the yield and purity of product were 93.6 % and 99.0 %, respectively. Compared to the synthesis methods reported in literatures, not only was the yield of product improved, but also two operating units were omitted. The product was characterized by 1H NMR and IR. KEY WORDS: One-pot synthesis, Spiroglycol, Pentaerythritol Bull. Chem. Soc. Ethiop. 2008, 22(1), 149-152.
One-pot synthesis of spiroglycol  [cached]
Jun Ming Xu,Fu Sheng Liu,Shi Tao Yu
Bulletin of the Chemical Society of Ethiopia , 2008,
Abstract: The synthesis of spiroglycol by one-pot reaction was studied using pentaerythritol, isobutyraldehyde and formaldehyde as starting materials. Under the optimum reacting conditions, the yield and purity of product were 93.6 % and 99.0 %, respectively. Compared to the synthesis methods reported in literatures, not only was the yield of product improved, but also two operating units were omitted. The product was characterized by 1H NMR and IR.
Sustainable Throughput of Wireless LANs with Multi-Packet Reception Capability under Bounded Delay-Moment Requirements  [PDF]
Ying Jun,Zhang,Soung Chang Liew,Darui Chen
Computer Science , 2010,
Abstract: With the rapid proliferation of broadband wireless services, it is of paramount importance to understand how fast data can be sent through a wireless local area network (WLAN). Thanks to a large body of research following the seminal work of Bianchi, WLAN throughput under saturated traffic condition has been well understood. By contrast, prior investigations on throughput performance under unsaturated traffic condition was largely based on phenomenological observations, which lead to a common misconception that WLAN can support a traffic load as high as saturation throughput, if not higher, under non-saturation condition. In this paper, we show through rigorous analysis that this misconception may result in unacceptable quality of service: mean packet delay and delay jitter may approach infinity even when the traffic load is far below the saturation throughput. Hence, saturation throughput is not a sound measure of WLAN capacity under non-saturation condition. To bridge the gap, we define safe-bounded-mean-delay (SBMD) throughput and safe-bounded-delay-jitter (SBDJ) throughput that reflect the actual network capacity users can enjoy when they require finite mean delay and delay jitter, respectively. Our earlier work proved that in a WLAN with multi-packet reception (MPR) capability, saturation throughput scales super-linearly with the MPR capability of the network. This paper extends the investigation to the non-saturation case and shows that super-linear scaling also holds for SBMD and SBDJ throughputs. Our results here complete the demonstration of MPR as a powerful capacity-enhancement technique for WLAN under both saturation and non-saturation conditions.
Catalyst Free One-Pot Synthesis of Chromeno Quinolines and Their Antibacterial Activity  [PDF]
Sruthi Vasamsetty, Sunitha Medidi, Satheesh Ampolu, Ravi Kumar Majji, Mastan Rao Kotupalli, Chikurumilli China Satyanarayana, Annapurna Nowduri, Paul Douglas Sanasi
Green and Sustainable Chemistry (GSC) , 2017, DOI: 10.4236/gsc.2017.72011
Abstract: An efficient greener one pot synthesis of dimethyl-dihydro-7H-chromeno[3, 2-h]quinolin-8(9H)-one derivatives has been synthesized through cyclization of aromatic aldehyde, dimidone and 8-hydroxy-quinoline through one-pot condensation method is described. The synthesized compounds are screened for further biological activities against Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Bacillus subtilis, Bacillus using cut plate method and disc diffusion method.
Cobalt(II) chloride catalyzed one-pot synthesis of α-aminonitriles
De Surya K
Beilstein Journal of Organic Chemistry , 2005, DOI: 10.1186/1860-5397-1-8
Abstract: A simple and efficient method has been developed for the synthesis of α-aminonitriles by a one-pot three- component condensation of aldehydes, amines, and potassium cyanide in acetonitrile in the presence of a catalytic amount of CoCl2 at room temperature.
Estimation of process capability indices in case of distribution unlike the normal one  [PDF]
A. Czarski
Archives of Materials Science and Engineering , 2008,
Abstract: Purpose: The aim of this paper is to show how it could utilize the statistical methods for the process management.Design/methodology/approach: The research methodology base on theoretical analysis and on empirical researches.It is presented a practical solution for estimation of process capability indices In case non-normal distribution.Findings: The Clements’ method brings sufficiently correct results for the analyzed case.Research limitations/implications: The future research will contain analysis for other non-normal distributions.Practical implications: Described methodology and results can be employed in industrial practice.Originality/value: Comparative analysis of capability indices determination in case of distribution unlike thenormal one.
One pot synthesis of 2-hydroxy pyrrolidine derivatives  [PDF]
Putta. P. Varma,Kittappa. M. Mahadevan,Abdul Khader,Vijaykumar Hulikal
Organic Communications , 2011,
Abstract: One pot reaction of various 2-amino-thiadiazoles or thiazoles and 2,3- dihydrofuran under mild condition in presence of CeCl 3.7H 2O as catalyst transformed the amino group of 2-amino-thiadiazoles or thiazoles into a medicinally important 2-hydroxy pyrrolidine ring system in good to excellent yields. The generality of the reaction was sufficiently investigated and demonstrated. The new reaction path way for this conversion was established by spectroscopic and analytical methods.
One-pot multicomponent route to propargylamines using ferric hydrogensulfate  [cached]
Hossein Eshghi,Gholam Hossein Zohuri,Saman Damavandi
European Journal of Chemistry , 2011, DOI: 10.5155/eurjchem.2.1.100-103.175
Abstract: The one-pot three-component coupling reaction of phenylacetylene, aldehyde and amine derivatives in the presence of ferric hydrogensulfate, [(Fe(HSO4)3], as an efficient heterogeneous catalyst is reported. The catalyst displayed high activity and afforded the corresponding propargylamines in good to excellent yields. This method provides the wide range of substrate applicability. Heterogeneous nature of the catalyst made it reusable for further chemical reactions.
One-Hop Throughput of Wireless Networks with Random Connections  [PDF]
Seyed Pooya Shariatpanahi,Babak Hossein Khalaj,Kasra Alishahi,Hamed Shah-Mansouri
Mathematics , 2011,
Abstract: We consider one-hop communication in wireless networks with random connections. In the random connection model, the channel powers between different nodes are drawn from a common distribution in an i.i.d. manner. An scheme achieving the throughput scaling of order $n^{1/3-\delta}$, for any $\delta>0$, is proposed, where $n$ is the number of nodes. Such achievable throughput, along with the order $n^{1/3}$ upper bound derived by Cui et al., characterizes the throughput capacity of one-hop schemes for the class of connection models with finite mean and variance.
Throughput Analysis of Many to One Multihop Wireless Mesh Ad hoc Network  [PDF]
Dr.S.Senthil Kumar,V.Ponniyin Selvan
International Journal on Computer Science and Engineering , 2011,
Abstract: Mobile ad hoc networks are formed by co operative association of wireless nodes communicating with each other without the use of infrastructure. Every node acts as a router in the network and enables the communication between nodes that are separated over their radio range. Typically in ad hoc networks one or more nodes may act as gateway connecting to the external world. The node acting as the gateway becomes a sink and the throughput capacity of the network in such networks becomes crucial to maintain QOS. This paper investigates throughput of many to one scenarios in wireless mesh network using Ad hoc On Demand Vector (AODV) Routing Protocol. It is proposed to specifically investigate the throughput of one hop, two hop and three hops to the sink in the wireless mesh network. Investigations are also carried out to measure the throughput of the wireless mesh network when the route timeout variable in the AODV routing protocol is decreased.
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