bluuebunny/crossref_metadata_2025 huggingface dataset:
Enhanced Photocatalytic Activity of Thienyl‐Porphyrins‐TiO2 for Degradation of 4‐Nitrophenol
Authors: Ma Wangyang , Li Jun , Liu Jingzhou , Feng Meng
Published: October 2012

5‐Mono‐(2‐thienyl)‐10,15,20‐triphenyl porphyrin (H2MTP) and its Co(II), Cu(II), Zn(II) metalloporphyrins (CoMTP, CuMTP, ZnMTP) were synthesized and characterized spectroscopically. The corresponding Co(II), Cu(II), Zn(II) metalloporphyrins‐TiO2 photocatalysts were then prepared and characterized by means of scanning electron microscopy (SEM), energy dispersive spectrometer (EDS), UV‐vis spectra and FT‐IR. The photocatalytic activities of these photocatalysts were investigated by testing the photodegradation of 4‐nitrophenol (4‐NP) in aqueous solution under irradiation with high‐pressure mercury lamp and metal halide lamp respectively. The results indicated that these metalloporphyrins greatly enhanced the photocatalytic efficiency of bare TiO2 in degradating the 4‐NP, and CuMTP‐TiO2 exhibited the highest photocatalytic activity of all photocatalysts. In addition, the first order rate constants of these photocatalytic reactions were calculated.
Accurate Prediction of AuP Bond Strengths by Density Functional Theory Methods
Authors: Yu Haizhu , Liu Dingjia , Dang Zhimin , Wang Dongrui , Fu Yao
Published: October 2012

The recent development of Au‐catalyzed reactions has greatly enriched the methods of organic synthesis. The phosphine or phosphate‐coordinated Au complexes have shown high efficiency in catalyzing various CC and CH activations. In many of these reactions, the AuP bond strength was found to play an important role in determining the catalytic efficiency. In the present study, the accuracy of different theoretical methods for prediction of AuP strengths has been examined on basis of the experimental enthalpy changes between different ClAu(PR3) and ClAu(THT) (THT=tetrahydrothiophene). By comparing the different DFT functionals (e.g. B3LYP, TPSS, M06), different basis sets (including the different effective core potentials on Au and the total electron basis sets on all other atoms), and different solution phase single point calculations, we found that the TPSS/(CPE‐121G+f:6‐311+G(d,p)(SMD)//TPSS/(CPE‐121G:6‐31G(d) (M1) method gives the best correlations with the available experimental results. Meanwhile, the calculations with B3LYP//TPSS and M05//TPSS also give comparable calculation results. Finally, the specified method (M1) is used to calculate the AuP bond dissociation enthalpies and energies of different ClAu(PR3)/ClAu(P(OR)3) complexes. By accurately reproducing the available experimental results, we believe that the method (M1) is reliable for the theoretical analysis of Au‐P systems.
A Facile Access to Fluorinated Pyrrolidines via Catalytic Asymmetric 1,3‐Dipolar Cycloaddition of Azomethine Ylides with Methyl α‐Fluoroacrylate
Authors: Yan Dingce , Li Qinghua , Wang Chunjiang
Published: October 2012

Asymmetric 1,3‐dipolar cycloaddition of methyl α‐fluoroacrylate with azomethine ylides for the construction of optically active fluorinated pyrrolidines bearing one unique fluorinated quaternary and two tertiary stereogenic centers has been achieved with Cu(CH3CN)4BF4/TF‐BiphamPhos complexes for the first time. This catalytic system performs well over a broad scope of substrates, providing the synthetically useful adducts in good yields and excellent diastereoselectivities and good to high enantioselectivities.
Enantioselective and α‐Regioselective Allylic Amination of Morita‐Baylis‐Hillman Acetates with Simple Aromatic Amines Catalyzed by Planarly Chiral Ligand/Palladium Catalyst
Authors: Wang Yan , Zhang Tao , Liu Li
Published: October 2012

An asymmetric allylic amination of Morita‐Baylis‐Hillman acetates with simple aromatic amines catalyzed by planarly chiral ligand/palladium‐catalyst was developed in good yield with excellent α‐regioselectivity (α/γ up to 30:1) and moderate enantioselectivity (up to 70% ee).
Cu(II)‐Catalyzed Enantioselective Conjugate Reduction for the Synthesis of N‐Aryl β‐Amino Acid Esters
Authors: Sui Yaozong , Fang Qiang , Li Min , Hu Yihu , Xia Hongfeng , Li Shijun , Wu Jing
Published: October 2012

A new set of reaction conditions has been established and allowed for the first non‐noble Cu(II)‐catalyzed asymmetric 1,4‐hydrosilylation of N‐aryl β‐enamino esters under air to afford a selection of N‐aryl β‐amino acid esters of moderate‐to‐good enantiopurities (ee up to 91%).
Iridium‐Catalyzed Allylic Alkylations of Sodium Phenyl Selenide
Authors: Cui Ruimin , Guo Xinwen , Zheng Shengcai , Zhao Xiaoming
Published: October 2012

An iridium‐catalyzed allylic substitution of sodium phenyl selenide with unsymmetrical allyl carbonates was accomplished, which produced the linear allyl phenyl selenides in 38%–74% yields. An asymmetric iridium‐catalyzed allylation of sodium phenyl selenide was presented as well.
An Efficient Asymmetric Domino Reaction of Amino Aldehyde to β,γ‐Unsaturated α‐Keto Esters Using trans‐Perhydroindolic Acid as a Chiral Organocatalyst
Authors: Shen Jiefeng , An Qianjin , Liu Delong , Liu Yangang , Zhang Wanbin
Published: October 2012

An efficient asymmetric domino reaction of amino aldehyde to β,γ‐unsaturated α‐keto esters was achieved by using trans‐perhydroindolic acid 1d as a chiral organocatalyst with excellent asymmetric behavior. Under the optimal reaction conditions, products with more than 99% de and up to 93% ee were obtained in high chemical yield (up to 98%) for a series of β,γ‐unsaturated α‐keto esters. The methodology provided an efficient route to dihydropyran derivatives containing many substituent groups (including amino groups).
Ultrafast Photodynamics of the Indoline Dye D149 Adsorbed to Porous ZnO in Dye‐Sensitized Solar Cells
Authors: Rohwer Egmont , Richter Christoph , Heming Nadine , Strauch Kerstin , Litwinski Christian , Nyokong Tebello , Schlettwein Derck , Schwoerer Heinrich
Published: October 2012

We investigate the ultrafast dynamics of the photoinduced electron transfer between surface‐adsorbed indoline D149 dye and porous ZnO as used in the working electrodes of dye‐sensitized solar cells. Transient absorption spectroscopy was conducted on the dye in solution, on solid state samples and for the latter in contact to a I−/I3− redox electrolyte typical for dye‐sensitized solar cells to elucidate the effect of each component in the observed dynamics. D149 in a solution of 1:1 acetonitrile and tert‐butyl alcohol shows excited‐state lifetimes of 300±50 ps. This signature is severely quenched when D149 is adsorbed to ZnO, with the fastest component of the decay trace measured at 150±20 fs due to the charge‐transfer mechanism. Absorption bands of the oxidized dye molecule were investigated to determine regeneration times which are in excess of 1 ns. The addition of the redox electrolyte to the system results in faster regeneration times, of the order of 1 ns.
Sol–Gel‐Derived, Calcium‐Based, Copper‐Functionalised CO2 Sorbents for an Integrated Chemical Looping Combustion–Calcium Looping CO2 Capture Process
Authors: Kierzkowska Agnieszka M. , Müller Christoph R.
Published: October 2012

Using a sol–gel technique, new copper‐functionalised, calcium‐based CO2 sorbents were developed to integrate chemical looping combustion into the calcium looping scheme. In this process, the exothermic reduction of copper oxide with methane, carbon monoxide or hydrogen is used to provide the heat required to calcine (regenerate) calcium carbonate. The materials contained CuO and CaO in a molar ratio of either 1.3:1 or 3.3:1, were supported on Al2O3, MgO or MgAl2O4 and were characterised by means of X‐ray diffraction, N2 physisorption, scanning electron microscopy and temperature‐programmed reduction. All materials, independent of the precursors and support material used, possessed excellent cyclic oxygen‐carrying capacities. However, it was found that the presence of magnesium in the support stabilised the CO2 uptake and minimised carbon deposition. CuCa‐MgAl‐1.3:1 was the material that possessed the highest CO2 uptake of 0.13 g gmaterial−1 after 15 cycles of repeated carbonation/calcination–redox reactions.
Mixed metal oxide nanocomposites derived from layered double hydroxides as photocatalysts for C.I. Basic Blue 3 degradation under UV light
Authors: Rezvani Z. , Sarkarat M. , Khataee A. R. , Nejati K.
Published: October 2012

In this research we report synthesis of the heterostructure Mg‐Al‐Zn mixed metal oxide (ZnO/MMO) nanocomposite photocatalysts derived from Zn(OH)2/Mg‐Al‐layered double hydroxides (ZLDHs) precursors. The obtained samples were characterized by the X‐ray diffraction (XRD), FT‐IR, BET surface area, ICP and TG/DTG methods. The chemical compositions and morphology of the synthesized materials were investigated by the energy dispersive X‐ray analysis (EDX) and the transmission electron microscopy (TEM). The results reveal that at the reaction time 96 h, ZLDH has the highest crystalinity which was confirmed by the X‐ray diffraction spectra. The calcined samples at 500, 600 and 700 °C for 4 h show that the crystallinity of the nanocomposite improves with the increase of calcination temperature. The photocatalytic activities of synthesized nanocomposites were compared for the degradation of C. I. Basic Blue 3 (BB3) dye under UV illumination in aqueous solution. Among the synthesized nanocomposites, ZnO/MMO calcined at 700 °C shows the highest efficiency towards the removal of dye. The effect of UV illumination on the stability of ZnO in ZnO/MMO nanocomposite and pure ZnO was also investigated. The results showed that the photostability of ZnO in ZnO/MMO nanocomposite is increased compared to the pure ZnO.
Electrochemical Valorisation of Glycerol
Authors: Simões Mário , Baranton Stève , Coutanceau Christophe
Published: October 2012

The worldwide glycerol stocks are increasing; to make the biodiesel industry sustainable economically, this chemical could be used as a secondary primary raw material. Electric energy or hydrogen and added‐value‐chemical cogeneration becomes more and more an important research topic for increasing economical and industrial interests towards electrochemical technologies. Studies on glycerol electrooxidation for fuel or electrolysis cell applications are scarce. The valorisation of glycerol is generally performed by organic chemistry reactions forming, for example, esters, glycerol carbonates, ethers, acetals or ketals. Glycerol oxidation is made up of complex pathway reactions that can produce a large number of useful intermediates or valuable fine chemicals with presently limited market impact due to expensive production processes. Many of these chemical oxidation routes lead to significant amounts of undesired by‐products, and enzymatic processes are limited. Converse to classical heterogeneous processes, electrocatalytic oxidation processes can be tuned by controlling the nature, composition and structure of the electrocatalyts as well as the electrode potential. Such control may lead to very high selectivity and activity, avoiding or limiting product separation steps. The coupling of glycerol oxidation to produce chemicals with the oxygen reduction reaction in a fuel cell or water reduction reaction in an electrolysis cell on Pt‐free catalysts results either in coproduction of electrical energy or hydrogen for energy storage.
Functionalized Graphene for High Performance Lithium Ion Capacitors
Authors: Lee Ji Hoon , Shin Weon Ho , Ryou Myung‐Hyun , Jin Jae Kyu , Kim Junhyung , Choi Jang Wook
Published: October 2012

Lithium ion capacitors (LICs) have recently drawn considerable attention because they utilize the advantages of supercapacitors (high power) and lithium ion batteries (high energy). However, the energy densities of conventional LICs, which consist of a pair of graphite and activated carbon electrodes, are limited by the small capacities of the activated carbon cathodes. To overcome this limitation, we have engaged urea‐reduced graphene oxide. The amide functional groups generated during the urea reduction facilitate the enolization processes for reversible Li binding, which improves the specific capacity by 37 % compared to those of conventional systems such as activated carbon and hydrazine‐reduced graphene oxide. Utilizing the increased Li binding capability, when evaluated based on the mass of the active materials on both sides, the LICs based on urea‐reduced graphene oxide deliver a specific energy density of approximately 106 Wh kgtotal−1 and a specific power density of approximately 4200 W kgtotal−1 with perfect capacity retention up to 1000 cycles. These values are far superior to those of previously reported LICs and supercapacitors, which suggests that appropriately treated graphene can be a promising electrode material for LICs.
Network‐layer security for the Internet of Things using TinyOS and BLIP
Authors: Granjal Jorge , Monteiro Edmundo , Silva Jorge Sá
Published: October 2012

The design of standard communications and security mechanisms for resource‐constrained sensing applications and devices may provide an important contribution for its integration with the Internet and consequently towards the realization of what we nowadays identify as the Internet of Things. This vision will only be realizable if appropriate security mechanisms are available, and in this context we target the design and experimental evaluation of security mechanisms for communications at the network‐layer with sensing devices (smart objects) using the standard IPv6 protocol. Our work proposes and evaluates the usage of new compressed security headers for the network layer with smart objects. We implement and evaluate what is, as far as we know, the first proposal of security at the network layer experimentally evaluated using the TinyOS operating system and its networking stack. As we verify in the course of our evaluation study, various scenarios employing network‐layer secure communications involving smart objects are feasible, particularly when security mechanisms are designed to benefit from cross‐layer interactions that allow the optimization of expensive cryptographic operations. Copyright © 2012 John Wiley & Sons, Ltd.
Performance analysis of MIMO beamforming with imperfect feedback
Authors: Tang Lan , Zhang Xinggan , Bai Yechao , Zhu Pengcheng
Published: October 2012

The quality of channel state information at the transmitter (CSIT) is critical to MIMO beamforming systems. However, in practical wireless systems, CSIT suffers from imperfections originating from quantization effects, feedback error and feedback delay. In this paper, we study the impact of feedback error and delay on the symbol error rate of MIMO beamforming systems with finite rate feedback. The feedback channel is modeled as a uniform symmetric channel. We derive an symbol error rate upper bound that is tight for a good beamformer. We also quantify the diversity gain and array gain loss due to the feedback error and delay. The codebook design method that is applicable to the beamforming systems with error or delay feedback is discussed. Both analytical and simulation results show that feedback error and delay will make the system behave badly at high signal‐to‐noise ratios. Copyright © 2012 John Wiley & Sons, Ltd.
Water‐storage capacity controls energy partitioning and water use in karst ecosystems on the Edwards Plateau, Texas
Authors: Heilman James L. , Litvak Marcy E. , McInnes Kevin J. , Kjelgaard James F. , Kamps Ray H. , Schwinning Susanne
Published: October 2012

Woody plants are encroaching into grasslands and savannas of the karst Edwards Plateau, but their impacts on climate and hydrology are unclear because of high variability in soil depth and uncertainties about the contribution of water in fractured limestone to the water available to trees. Water use is controlled by available energy (AE) and its partitioning between latent (λE) and sensible (H) heat fluxes. We hypothesized that the partitioning of AE depends on soil depth, with greater depth leading to more λE and less H. We compared energy fluxes of a deep soil savanna with ~50% woody cover dominated by Ashe juniper (Juniperus ashei) and a shallow soil woodland dominated by live oak (Quercus virginiana) and juniper over a 5‐year period, which included periods of unusually high rainfall and severe drought. Although AE was 7% higher in the woodland, λE was about 2% higher at the savanna over the 5‐year study. Site differences in evapotranspiration were maximal during dry periods between rainfall events, suggesting greater storage of water at the savanna site. During periods of high rainfall, the impact of water storage limitations was minimal, and site differences in evapotranspiration were controlled mainly by AE and its partitioning into H. Both sites were characterized by rapid reductions in λE and reciprocal increases in H during drying cycles following rainfall, indicating that neither of these ecosystems had access to easily utilized sources of deep water. Copyright © 2012 John Wiley & Sons, Ltd.
Lymphotoxin α1β2 expression on B cells is required for follicular dendritic cell activation during the germinal center response
Authors: Myers Riley C. , King R. Glenn , Carter Robert H. , Justement Louis B.
Published: October 2012

CD19‐deficient mice were used as a model to study follicular dendritic cell (FDC) activation because these mice have normal numbers of FDC‐containing primary follicles, but lack the ability to activate FDCs or form GCs. It was hypothesized that CD19 expression is necessary for B‐cell activation and upregulation of membrane lymphotoxin (mLT) expression, which promotes FDC activation. Using VCAM‐1 and FcγRII/III as FDC activation markers, it was determined that the adoptive transfer of CD19+ wild‐type B cells into CD19‐deficient hosts rescued GC formation and FDC activation, demonstrating that CD19 expression on B cells is required for FDC activation. In contrast, CD19+ donor B cells lacking mLT were unable to induce VCAM‐1 expression on FDCs, furthermore FcγRII/III upregulation was impaired in FDCs stimulated with mLT‐deficient B cells. VCAM‐1 expression on FDCs, but not FcγRII/III, was rescued when CD19‐deficient B cells expressing transgenic mLT were cotransferred into recipient mice with CD19+, mLT‐deficient B cells, suggesting that FDC activation requires the CD19‐dependent upregulation of mLT on activated B cells. Collectively, these data demonstrate that activated B cells are responsible for the initiation of FDC activation resulting in a microenvironment supportive of GC development and maintenance.
The tyrosine kinase inhibitor dasatinib suppresses cytokine production by plasmacytoid dendritic cells by targeting endosomal transport of CpG DNA
Authors: Fujita Haruyuki , Kitawaki Toshio , Sato Takayuki , Maeda Takahiro , Kamihira Shimeru , Takaori‐Kondo Akifumi , Kadowaki Norimitsu
Published: October 2012

Plasmacytoid dendritic cells (pDCs) produce a vast amount of interferon (IFN)‐α in response to nucleic acids from viruses and damaged self‐cells through Toll‐like receptor (TLR)7 and TLR9. Pharmaceutical agents that suppress IFN‐α production by pDCs are instrumental in elucidating the mechanisms behind IFN‐α production, and in developing novel therapies for inflammatory disorders that involve pDCs. Here, we show that a tyrosine kinase inhibitor for chronic myeloid leukemia with multiple targets, dasatinib, strongly suppresses production of IFN‐α and proinflammatory cytokines by human pDCs stimulated with multimeric CpG oligodeoxynucleotides (CpG‐A) without reducing viability. In contrast, other tyrosine kinase inhibitors, imatinib, and nilotinib, did not suppress the cytokine production at clinically relevant concentrations. Inhibitors of SRC family kinases (SFKs), which are prominent targets of dasatinib, also suppressed the cytokine production. Notably, however, dasatinib, but not SFK inhibitors, abrogated prolonged localization of CpG‐A in early endosomes, which is a critical step for pDCs to produce a large amount of IFN‐α. This study suggests that dasatinib suppresses IFN‐α production by pDCs by inhibiting SFK‐dependent pathways and SFK‐independent endosomal retention of CpG DNA. Kinases controlling the distinctive endosomal trafficking in pDCs may be exploited as targets to develop novel therapies for pDC‐related inflammatory disorders.
Effect of Ligand Structure on MnO Nanoparticles for Enhanced T1 Magnetic Resonance Imaging of Inflammatory Macrophages
Authors: Park Joseph , Bang Doyeon , Kim Eunjung , Yang Jaemoon , Lim Eun‐Kyung , Choi Jihye , Kang Byunghoon , Suh Jin‐Suck , Park Hyo Seon , Huh Yong‐Min , Haam Seungjoo
Published: October 2012

Carboxymethyl‐dextran (CM‐dextran) replaced the hydrophobic oleylamine ligands on the surfaces of MnO nanoparticles, rendering them highly water‐soluble by allowing direct contact with excited water protons. Solution MRI studies of the two types of nanoparticles, exchanged and bilayered, with different core sizes have shown that the exchanged ligand structure exhibits significantly enhanced longitudinal relaxation. The modification with dextran converted the nanoparticles into effective T1 MRI contrast agents, as well as promoting strong interactions with macrophages. Thus, it is a potential MR contrast agent for visualizing inflammatory macrophages.
(E,E)‐1,2,3,4‐Tetracyclopropylbuta‐1,3‐diene: Synthesis and Some of Its Properties
Authors: de Meijere Armin , Redlich Stefan , Kozhushkov Sergei I. , Yufit Dmitry S. , Magull Jörg , Vidović Denis , Schill Heiko , Menzel Henning
Published: October 2012

(E,E)‐1,2,3,4‐Tetracyclopropylbuta‐1,3‐diene (3) and (Z,Z)‐1,4‐diodo‐1,2,3,4‐tetracyclopropylbuta‐1,3‐diene (4) were prepared from dicyclopropylacetylene via an intermediate 2,3,4,5‐tetracyclopropyltitanacyclopentadiene (2) in 91 and 77 % yield, respectively. In the crystal, 3 adopts a conformation with an almost coplanar (φ = 163°) 1,3‐diene core, with the inner vinylcyclopropane units in an orthogonal and the outer vinylcyclopropane moieties in an s‐trans orientation. This diene, like 2,3‐cyclopropylbuta‐1,3‐diene (5), undergoes facile concerted [4+2] cycloadditions at 130 °C with dimethyl acetylenedicarboxylate as well as N‐phenylmaleimide and at 0 °C with N‐phenyltriazolinedione. An X‐ray crystal structure analysis of 2,3‐dicyclopropylbuta‐1,3‐diene (5) also reveals a coplanar inner core with the vinylcyclopropane units in essentially orthogonal (φav = 89.3°) orientation. Differential scanning calorimetry (DSC) measurements indicate that 3 undergoes significant internal reorganization on going from the liquid to the crystalline phase, and a gauche conformer of 3 may well be favored over the s‐trans conformer in the liquid.
Acetamide as Cocatalyst for the Nitrogen‐Directed Coupling of Arenes with Aryl Chlorides through Ruthenium‐Catalyzed C–H Activation
Authors: Zhang Jie , Yang Qin , Zhu Zhu , Yuan Mao Lin , Fu Hai Yan , Zheng Xue Li , Chen Hua , Li Rui Xiang
Published: October 2012

A simple and highly efficient method for the cross‐coupling of aromatics by C–H activation is described. Acetamide was found to be an effective cocatalyst for this generally applicable ruthenium(II)‐catalyzed direct arylation reaction. A wide range of deactivated aryl chlorides could be efficiently coupled under the mild temperature of 101 °C. The new process is highly atom‐economical and sustainable.
Synthesis of the AB‐Ring Pyranolactone Substructure of Granaticin A
Authors: Bartholomäus Ruben , Bachmann Janina , Mang Christian , Haustedt Lars Ole , Harms Klaus , Koert Ulrich
Published: October 2012

A synthesis of the AB‐ring substructure of granaticin A was developed. The pyranolactone moiety was stereoselectively accessed by Sharpless asymmetric dihydroxylation and subsequent oxa‐Pictet–Spengler cyclization. The use of BF3·OEt2 resulted in the formation of the cis pyranolactone, whereas the combination of BF3·OEt2 with trifluoroacetic acid led to the trans isomer. The resulting hydroquinones were cleaved selectively by ozonolysis to dicarboxylic acids. An aryl Grignard reagent could be regioselectively added to unsymmetrical anhydrides. As an alternative strategy for the construction of the B‐ring, a benzyne–furan cycloaddition could be established.
A Novel Neutral Carrier for Uranyl Ion Based on a Commercially Available Aminophosphate Derivative: Evaluation in Membrane Electrodes and Nuclear Safeguards Applications
Authors: Badr Ibrahim H. A. , Zidan W. I. , Akl Z. F.
Published: October 2012

The construction and performance characteristics of uranyl membrane electrodes based on cheap and commercially available amino(trimethyl)phosphate are described. The influence of various membrane constituents on the potentiometric responses of the prepared membrane electrodes has been studied. Optimized membrane electrodes exhibited performance characteristics comparable with those based on high cost and commercially available ionophores. Selectivity studies indicated that the developed membrane electrodes are selective towards uranyl ion over a large number of cations including the well‐known uranyl ion interferents (e.g., Fe3+, Th+4). The analytical utility of the proposed membrane electrode has been demonstrated through its application in nuclear safeguards verification purposes.
Performance spectra based method for the seismic design of structures equipped with passive supplemental damping systems
Authors: Guo Jack Wen Wei , Christopoulos Constantin
Published: October 2012

A new direct performance‐based design method utilizing design tools called performance‐spectra (P‐Spectra) for low‐rise to medium‐rise frame structures incorporating supplemental damping devices is presented. P‐Spectra are graphic tools that relate the responses of nonlinear SDOF systems with supplemental dampers to various damping parameters and dynamic system properties that structural designers can control. These tools integrate multiple response quantities that are important to the performance of a structure into a single compact graphical format to facilitate direct comparison of different potential solutions that satisfy a set of predetermined performance objectives under various levels of seismic hazard. An SDOF to MDOF transformation procedure that defines the required supplemental damping properties for the MDOF structure to achieve the response defined by the target SDOF system is also presented for hysteretic, linear viscous and viscoelastic damping devices. Using nonlinear time‐history analyses of idealized shear structures, the accuracy of the transformation procedure is verified. A seismic performance upgrade design example is presented to demonstrate the usefulness of the proposed method for achieving design performance goals using supplemental damping devices. Copyright © 2012 John Wiley & Sons, Ltd.
Research on mobility handover for IPv6‐based MANET
Authors: Xiaonan Wang , Shan Zhong
Published: October 2012

The paper proposes a mobility handover scheme for IPv6‐based mobile ad hoc network (MANET) Mobility Handover (IMMH). In IMMH, when a node moves out of the communication scope of its upstream node, it is the node that directly establishes the routing path reaching to the upstream node in the Unicast way, which reduces the mobility handover cost and shortens the mobility handover delay. In mobile ad‐hoc networks without any infrastructures, a user always uses a node's home address to communicate with the node, and both the node's mobility handover process and its care‐of address update process are transparent to the user. Therefore, the communication continuity is ensured. From both the theoretical perspective and the simulative perspective, the paper analyzes the performance parameters of IMMH, including the mobility handover cost and the mobility handover delay. The data results show that the mobility handover cost of IMMH is lower and the delay is shorter.Copyright © 2012 John Wiley & Sons, Ltd.
Effects of agriculture production systems on nitrate and nitrite accumulation on baby‐leaf salads
Authors: Aires Alfredo , Carvalho Rosa , Rosa Eduardo A. S. , Saavedra Maria J.
Published: October 2012

Nitrate and nitrite are widespread contaminants of vegetables, fruits, and waters. The levels of these compounds are increased as a result of using organic wastes from chemical industries, domestic wastes, effluents, nitrogenous fertilizers, and herbicides in agriculture. Therefore, determining the nitrate and nitrite levels in biological, food, and environmental samples is important to protect human health and the environment. In this context, we set this study, in which we report the effect of production system (conventional and organic) on the accumulation of nitrates and nitrites in fresh baby‐leaf samples. The average levels of the nitrate (NO3−) and nitrite (NO2−) contents in six different baby‐leaf salads of a single species (green lettuce, red lettuce, watercress, rucola, chard, and corn salad) produced in organic and conventional agriculture system were evaluated. Spectrophotometric analytical method recently published was validated and used. Nitrates and nitrites were detected in all samples. The nitrates levels from organic production varied between 1.45 and 6.40 mg/kg fresh weight (FW), whereas those from conventional production ranged from 10.5 to 45.19 mg/kg FW. The nitrites content was lower than nitrates and ranged from 0.32 to 1.89 mg/kg FW in organic production system and between 0.14 and 1.41 mg/kg FW in conventional production system. Our results showed that the nitrate content was dependent on the agricultural production system, while for nitrites, this dependency was less pronounced.
Physico‐chemical and sensory properties of cookies made from blends of germinated pigeon pea, fermented sorghum, and cocoyam flours
Authors: Okpala Laura , Okoli Eric , Udensi Emelem
Published: October 2012

Cookies were produced from germinated pigeon pea, fermented sorghum, and cocoyam flour (CF) blends to determine their potentials in cookie manufacture. Ten flour formulations were produced and they were evaluated for their proximate and functional properties. Protein content ranged from 4.85% to 19.89% with 100% CF (100CF) having the least value, while 100% germinated pigeon pea flour (100GPF) had the highest value. Increase in levels of GPF to the flour blends resulted in increase in protein content of the blends. Cookies made with 100% fermented sorghum flour (100FSF) had the highest ash content of 2.73%, while cookies made with 100GPF had the least ash content. Energy values of the cookies ranged between 369.37 and 376.56 kcal/100 g, with cookie formulation 50%CF:50%FSF having the least value and cookies made with 16.7%CF:16.7%FSF:66.6GPF having the highest value. The control (cookies made with wheat) had the highest spread ratio of 24.13, while cookies made with 100FSF had the least spread ratio of 14.97. Cookies made with 100CF were the least fragile. Sensory ratings revealed that cookies containing up to 50% CF and above, compared favorably with those made with wheat flour.
Supplementing long‐chain n‐3 polyunsaturated fatty acids in canned wild Pacific pink salmon with Alaska salmon oil
Authors: Lapis Trina J. , Oliveira Alexandra C. M. , Crapo Charles A. , Himelbloom Brian , Bechtel Peter J. , Long Kristy A.
Published: October 2012

Establishing n‐3 polyunsaturated fatty acid contents in canned wild Alaska pink salmon products is challenging due to ample natural variation found in lipid content of pink salmon muscle. This study investigated the effect of adding salmon oil (SO) to canned pink salmon produced from fish exhibiting two opposite degrees of skin watermarking, bright (B) and dark (D). Specific goals of the study were to evaluate the benefits of adding SO to canned pink salmon with regard to nutritional value of the product, sensory characteristics, and the oxidative and hydrolytic stability of the lipids over thermal processing. Six groups of canned pink salmon were produced with variable levels of SO, either using bright (with 0, 1, or 2% SO) or dark (with 0, 2, or 4% SO) pink salmon. Compositional analysis revealed highest (P < 0.05) lipid content in sample B2 (8.7%) and lowest (P < 0.05) lipid content in sample D0 (3.5%). Lipid content of samples B0, B1, D2, and D4 was not significantly different (P > 0.05) ranging from 5.7% to 6.8%. Consequently, addition of SO to canned pink salmon allowed for consistent lipid content between bright and dark fish. Addition of 1% or 2% SO to canned bright pink salmon was not detrimental to the sensory properties of the product. It is recommended that canned bright pink salmon be supplemented with at least 1% SO, while supplementation with 2% SO would guarantee a minimum quantity of 1.9 g of n‐3 fatty acids per 100 g of product. Addition of 4% SO to canned dark pink salmon was detrimental to product texture and taste, while supplementation with 2% SO did not negatively affect sensorial properties of the product. Accordingly, canned dark pink salmon should be supplemented with 2% SO so that a minimum n‐3 fatty acids content of 1.5 g per 100 g of product.
Comparative lethality kinetic curves and predictive models of F‐value for Listeria monocytogenes using different sanitizers
Authors: Beltrame Cezar A. , Kubiak Gabriela B. , Rottava Ieda , Toniazzo Geciane , Cansian Rogério L. , Lerin Lindomar A. , de Oliveira Débora , Treichel Helen
Published: October 2012

The objective of this work was to evaluate the kinetic of inactivation of Listeria monocytogenes using peracetic acid, chlorhexidine, and organic acids as active agent, determining the respective D‐, Z‐, and F‐values. From our knowledge, these important results from an industrial view point are not available in the current literature, mainly for organic acids, pointing out the main contribution of the present work. Lower D‐values were obtained for peracetic acid and chlorhexidine, compared with the organic acids. For the reduction of 6 log10 of L. monocytogenes using peracetic acid, at 0.2, 0.1, and 0.05% are necessary 7.08, 31.08, and 130.44 min of contact, respectively. The mathematical models of F‐values showed that at concentrations lower than 0.15% one can verify an exponential increase in F‐values, for both de chlorhexidine and peracetic acid. The organic acids presented a linear behavior, showing slight variation in F‐values, is even more effective in under dosage. The results obtained are of fundamental importance in terms of industrial strategy for sanitization procedure, permitting to choose the best relation product concentration/exposure time, aiming at reducing costs without compromising the disinfectant efficiency.
Distinct evolution and predictive value of hepatitis B virus precore and basal core promoter mutations in interferon-induced hepatitis B e antigen seroconversion
Authors: Yang Hung-Chih , Chen Chi-Ling , Shen Yueh-Chi , Peng Cheng-Yuan , Liu Chun-Jen , Tseng Tai-Chung , Su Tung-Hung , Chuang Wan-Long , Yu Ming-Lung , Dai Chia-Yen , Liu Chen-Hua , Chen Pei-Jer , Chen Ding-Shinn , Kao Jia-Horng
Published: October 2012

Precore (PC) (G1896A) and basal core promoter (BCP) (A1762T/G1764A) mutations of the hepatitis B virus (HBV) genome often emerge in chronic hepatitis B (CHB) patients. Their roles in hepatitis B e antigen (HBeAg) seroconversion induced by interferon (IFN) therapy remain controversial, partly because quantitative analysis for these mutants is lacking. This study aimed to develop a new assay to accurately quantify the PC and BCP mutant percentages and correlate their dynamic changes with IFN-induced HBeAg seroconversion in HBeAg-positive CHB patients. The PC and BCP mutant percentages were analyzed by polymerase chain reaction (PCR)-pyrosequencing. Our results showed that this quantitative assay for PC and BCP mutants achieved high accuracy (R2 > 0.99) within a range between 10% and 90% mutants. We examined dynamic changes of the PC and BCP mutant percentages following IFN treatment in 203 HBeAg-positive CHB patients. By multiple logistic regression analysis, we found that the chance of HBeAg seroconversion increased by 2.2% (odds ratio [OR] = 1.022, 95% confidence interval [CI]: 1.009–1.034,

P

= 0.001) and 2.3% (OR = 1.023, 95% CI: 1.010–1.037,

P

= 0.001) per 1% increase of the pretreatment PC and BCP mutant percentages, respectively, after adjustment for other predictors. However, only the pretreatment PC mutation percentage was significantly associated with HBeAg seroconversion with HBV DNA < 2,000 IU/mL (OR = 1.030, 95% CI: 1.014–1.047,

P

< 0.001). Furthermore, the mutant percentage of PC, but not BCP, in patients achieving HBeAg seroclearance with HBV DNA < 20,000 IU/mL increased significantly during IFN treatment (
P

= 0.039). Interestingly, patients with HBeAg seroconversion who had a high PC mutant percentage at the end of IFN treatment tended to exhibit high viremia after seroconversion.

Conclusion:

Quantitative analysis of PC and BCP mutants can predict IFN-induced HBeAg seroconversion and demonstrate their distinct evolution patterns during HBeAg seroconversion. (Hepatology 2013)
Inhibitory effects of tert‐butylhydroquinone on osteoclast differentiation via up‐regulation of heme oxygenase‐1 and down‐regulation of HMGB1 release and NFATc1 expression
Authors: Yamaguchi Yu , Sakai Eiko , Sakamoto Hiroshi , Fumimoto Reiko , Fukuma Yutaka , Nishishita Kazuhisa , Okamoto Kuniaki , Tsukuba Takayuki
Published: October 2012

Osteoclasts (OCLs) are multinucleated bone‐resorbing cells that are differentiated by receptor activator of nuclear factor kappa‐B ligand (RANKL) and macrophage colony‐stimulating factor (M‐CSF). Our recent studies have shown that heme‐oxygenase‐1 (HO‐1), a stress‐induced cytoprotective enzyme, plays an important role in OCL differentiation, although the pharmacological significance of this effect remains unknown. In this study, we investigated the effects of tert‐butylhydroquinone (tBHQ), a pharmacological HO‐1 inducer, on in vitro differentiation of bone marrow‐derived macrophages (BMMs) or murine monocytic cell line RAW‐D into OCLs. tBHQ inhibited the formation and the bone‐resorbing activity of OCLs. Moreover, tBHQ treatment decreased the expression of nuclear factor of activated T cells cytoplasmic‐1 (NFATc1), a master regulator of OCL differentiation, and of OCL markers transcriptionally regulated by NFATc1, such as Src and cathepsin K. In addition, tBHQ impaired phosphorylation of extracellular signal‐regulated kinase, p38 mitogen‐activated protein kinase (MAPK), Jun N‐terminal kinase, Akt, and inhibitor of nuclear factor kappa B alpha (IκBα). Finally, we show that tBHQ inhibited the release of high mobility group box 1 (HMGB1), a recently identified activator of OCL differentiation. Thus, tBHQ inhibits OCL differentiation through the HO‐1/HMGB1 pathways. Copyright © 2012 John Wiley & Sons, Ltd.
Synthesis, Characterization, and In Vitro Microbial Evaluation of Some New 4H‐Chromene and Quinoline Derivatives of 1H‐Pyrazole
Authors: Thumar Nilesh J. , Patel Manish P.
Published: October 2012

A new series of nine derivatives of 4H‐pyrano[3,2‐c]chromene and 12 derivatives of N‐thiazolyl‐4H‐quinoline of 1H‐pyrazole has been synthesized by one pot base catalyzed cyclocondensation reaction of 1H‐pyrazole‐4‐carbaldehyde, malononitrile, and 4‐hydroxy coumarin or β‐enaminones, respectively. All the synthesized compounds were characterized by elemental analysis, FT‐IR, 1H NMR, 13C NMR spectral data and were further screened, against a panel of pathogenic strains of bacteria and fungi.
Synthesis of Monosubstituted 1,3,4‐Selenadiazoles Using Woollins' Reagent
Authors: Ostrowski Wojciech , Gierczyk Błażej , Frański Rafał
Published: October 2012

New series of 1,3,4‐selenadiazoles was obtained. The method of synthesis employs the Woollins' reagent andN,N′‐diacylhydrazides. Reaction in toluene leads to monosubstituted 1,3,4‐selenadiazoles with a yield 26–57%.
Multinuclear NMR Characterization of Cyanuric Fluoride (2,4,6‐Trifluoro‐1,3,5‐triazine)
Authors: Fresno Nieves , Pérez‐Fernández Ruth , Luisa Jimeno M. , Alkorta Ibon , Sánchez‐Sanz Goar , Elguero José , Del Bene Janet E.
Published: October 2012

Although 2,4,6‐trifluoro‐1,3,5‐triazine, C3F3N3, is a highly symmetrical molecule, its NMR parameters can be obtained by reducing its symmetry through the introduction of 14N/15N and 12C/13C isotopomers. Experimental and computed chemical shifts of cyanuric fluoride have been obtained for 13C, 15N, and 19F. Spin‐spin coupling constants have been measured and compared with previous experimental data and with the complete set of computed EOM‐CCSD coupling constants.
Reaction of Phthalaldehyde with Aminoethanol under Different Conditions: Products and Mechanisms of Their Formation
Authors: Klíma Jiří , Polášek Miroslav , Ludvík Jiří , Urban Jiří
Published: October 2012

Analysis of amino acids and very efficient disinfection procedures are based on the reaction of phthalaldehyde (OPA) with primary amines. In this contribution, aminoethanol (=kolamin) as a nitrogen‐containing nucleophile was used for the investigation of its reaction mechanism with OPA performed in basic aqueous buffered media (pH 9.5), where an influence of hydration or solvation is expected, and in anhydrous acetonitrile. Depending on the detailed reaction conditions, seven products were isolated and their structures determined by NMR, mass spectrometry, and X‐ray structure analysis. Reaction mechanisms are proposed, which involve hydride transfers to OPA (Cannizzaro‐type reaction).

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Thieno[2,3‐d]pyrimidines in the Synthesis of New Fused Heterocyclic Compounds of Prospective Antitumor and Antioxidant Agents (Part II)
Authors: Aly Ashraf A. , Ramadan Mohamed , Mohamed Ashraf M. , Ishak Esam A.
Published: October 2012

Diethyl azodicarboxylate and 3,4,5,6‐tetrachloro‐1,2‐benzoquinone react with cyclopentano‐ and cycloheptano‐fused thienopyrimidines to form the oxidative dimer of the starting material via S—S bond formation. Reaction of two equivalents of 2,2′‐(cyclohexa‐2′,5′‐diene‐1,4‐diylidene)dimalononitrile with thienopyrimidines afforded 3‐(4′,4′‐dicyanomethylene‐cycloalka[a]‐2,5‐dienyl)‐4‐oxo‐6,7,8,9‐tetrahydro‐5H‐cyclo‐hepta[4,5]‐[1,3]thiazolo[3,2‐a]‐thieno[2,3‐d]pyrimidin‐2‐ylidene‐2‐dicarbonitriles. The thioenopyrimidines react with 2‐[1,3‐dioxo‐1H‐inden‐2(3H)‐ylidene]malononitrile to produce 1,3,5′‐trioxo‐1,3,3′,5′‐tetrahydrospiro‐(indene‐2,2′‐thiazolo[2,3‐b]‐cycloalkyl[b]‐thieno[2,3‐d]pyrimidine)‐3′‐carbonitriles. However, the reaction of thienopyrimidines with 2,3‐dicyano‐1,4‐naphthoquinone proceeded to afford the fused cycloalkyl‐thieno form of naphtho[1,3]thiazolo[3,2‐a]thieno[2,3‐d]pyrimidine‐6.7,12‐triones. Reaction of 2‐hydrazino‐5,6,7,8‐tetrahydrobenzo[b]thieno[2,3‐d]pyrimidine‐4(1H)‐one with dimethyl acetylenedicarboxylate and ethyl propiolate, respectively, afforded cyclohexano‐fused (Z)‐dimethyl 2[(E)‐4‐oxo‐3,4‐dihydrothieno[2,3‐d]pyrimidine‐2(1H)‐ylidene)hydrazono]succinate and thieno‐pyrimidinotriazine. Both oxidative dimers of thienopyrimidines showed high inhibition of Hep‐G2 cell growth compared with the growth of untreated control cells. Moreover, the cycloheptano‐fused thiazinothienopyrimidine indicates a promising specific antitumor agent against Hep‐G2 cells because its IC50 is < 20 μM.
Synthesis and Antimicrobial Activity of Linked Heterocyclics Containing Pyrazole and Oxadiazoles
Authors: Reddy Ch. Sanjeeva , Rao L. Sanjeeva , Devi M. Vani , Nagaraj A.
Published: October 2012

A new series of 3‐(arylaminomethyl)‐5‐(5‐methyl‐1‐phenyl‐1H‐4‐pyrazolyl)‐2,3‐dihydro‐1,3,4‐oxadiazole‐2‐thiones 6a, 6b, 6c, 6d, 6e, 6f, 6g, 6h, 6i, 6j has been synthesized by the reaction of 5‐(5‐methyl‐1‐phenyl‐1H‐4‐pyrazolyl)‐1,3,4‐oxadiazol‐2‐ylhydrosulfide 5 with formaldehyde and corresponding anilines. The chemical structures of newly synthesized compounds were elucidated by IR, 1H, 13C‐NMR, MS, and elemental analyses. The compounds 6a, 6b, 6c, 6d, 6e, 6f, 6g, 6h, 6i, 6j were evaluated for their antibacterial activity against three representative Gram positive bacteria viz. Bacillus subtilis (MTCC 441), Bacillus sphaericus (MTCC 11) and Staphylococcus aureus (MTCC 96), and three Gram negative bacteria viz. Pseudomonas aeruginosa (MTCC 741), Klobsinella aerogenes (MTCC 39) and Chromobacterium violaceum. Among the screened 6b, 6d, 6i, and 6j in which oxadiazole moiety bearing 4‐fluoroanilinomethyl, 4‐chloroanilinomethyl, 2‐trifluoromethylanilinomethyl, and 2,5‐difluoroanilinomethyl groups, respectively, showed high activity against all the microorganisms used. In addition these compounds were also screened for their antifungal activity against four fungal organisms viz. Candida albicans (ATCC 10231), Aspergillus fumigatus (HIC 6094), Trichophyton rubrum (IFO 9185), and Trichophyton mentagrophytes (IFO 40996). Most of these new compounds showed appreciable activity against test fungi, and emerged as potential molecules for further development.
β‐Functionalized meso Tetrahalothien‐2‐ylporphyrins: Synthesis, Spectral, and Electrochemical Properties
Authors: Prasath R. , Bhavana P.
Published: October 2012

Two types of β‐ functionalized (mono nitrated and perbrominated) meso tetrakis(5‐halothien‐;2‐yl)porphyrins, which can be used as precursors for the synthesis of other asymmetric and highly substituted porphyrins, have been synthesised and characterized. Introduction of a nitro group at the β‐ position shifted soret band 11–16 nm to the red region and redox potentials to > 170 mV for oxidation and > 250 mV for reduction anodically. Perbromination of halothienylporphyrins lead to enhanced bathochromically shifted uv‐visible spectral bands, but had only marginal influence on oxidation potentials. Effect of mono nitro group and eight bromo groups on the electronic properties of the porphyrins is attributed, respectively to, the electron deficiency created in the porphyrin π‐ system and the nonplanar conformation induced by the bulky bromo groups.
Synthesis of Novel Spiro Thiazolotriazole Derivatives via1,3‐Dipolar Cycloaddition of Azomethine Ylide
Authors: Xiaofang Li , Bin Liu , Haochong Liu , Xianyong Yu , Pinggui Yi
Published: October 2012

The 1,3‐dipolar cycloaddition of azomethine ylide generated in situ from isatin and sarcosine to 5‐arylmethylidene thiazolo[3,2‐b][1,2,4]triazol‐6(5H)‐ones afforded novel 1′‐methyl‐4′‐aryldispiro[indole‐3,2′‐pyrrolidine‐3′,5″‐[1,3]thiazolo[3,2‐b][1,2,4]triazole]‐2,6″ (1H)‐diones in moderate yields. The structures of all the products were characterized thoroughly by NMR, infrared spectroscopy (IR), mass spectroscopy (MS) elemental analysis together with X‐ray crystallographic analysis.
Organoiodine(III) Mediated Synthesis of Novel Symmetrical Bis([1,2,4]triazolo)[3,4‐a:4′,3′‐c]phthalazines as Antibacterial and Antifungal Agents
Authors: Prakash Om , Aneja Deepak K. , Hussain Khalid , Kumar Ravi , Arora Sanjiv , Sharma Chetan , Aneja Kamal R.
Published: October 2012

A series of new symmetrical 3,6‐bis(aryl)bis([1,2,4]triazolo)[3,4‐a:4′,3′‐c]phthalazines 9a‐l has been conveniently synthesized by oxidative cyclization of 1,4‐bis(substituted benzalhydrazino)phthalazines 8a‐l promoted by iodobenzene diacetate under mild conditions (12 examples, up to 93% yield). All the 12 compounds were tested in vitro for their antibacterial activity against two Gram‐positive bacteria, namely, Staphylococcus aureus, Bacillus subtilis and two Gram‐negative bacteria, namely, Escherichia coli and Pseudomonas aeruginosa. All the synthesized compounds were also tested for their antifungal action against two fungi, Aspergillus niger and Aspergillus flavus.
Microwave‐Assisted Synthesis of Bis(enaminoketones): Versatile Precursors for Novel Bis(pyrazoles) viaRegioselective1,3‐Dipolar Cycloaddition with Nitrileimines
Authors: Elwahy Ahmed H. M. , Darweesh Ahmed F. , Shaaban Mohamed R.
Published: October 2012

Synthesis of bis(enaminones) 6a, 6b, 6c and 7a, 7b, 7c was accomplished by the reaction of bis(acetophenones) 3a, 3b, 3c and 4a, 4b, 4c with dimethylformamide–dimethylacetal, under microwave irradiation. 1,3‐Dipolar cycloaddition of bis(enaminones) 6a and 7b, 7c with nitrileimines in refluxing benzene led to the regioselective synthesis of the novel bis(pyrazoles) 11a, 11b, 11c, 11d, 11e, 11f, 11g, 11h in 62–89% yield. The bis(pyrazoles) 11b, 11c underwent condensation with hydrazine hydrate to give the corresponding bis(pyrazolo[3,4‐d]pyridazines) 14a, 14b in good yields.