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61.
Synthesis of 3-(′, 1′-dimethylallyl)herniarin and 3-(′, 1′-dimethylallyl)desmothosyherniarin has been carried out by a versatile route. 相似文献
62.
Aamodt K Abelev B Quintana AA Adamová D Adare AM Aggarwal MM Rinella GA Agocs AG Salazar SA Ahammed Z Masoodi AA Ahmad N Ahn SU Akindinov A Aleksandrov D Alessandro B Molina RA Alici A Alkin A Aviña EA Alt T Altini V Altinpinar S Altsybeev I Andrei C Andronic A Anguelov V Anson C Antičić T Antinori F Antonioli P Aphecetche L Appelshäuser H Arbor N Arcelli S Arend A Armesto N Arnaldi R Aronsson T Arsene IC Asryan A Augustinus A Averbeck R Awes TC Aystö J Azmi MD Bach M Badalà A Baek YW 《Physical review letters》2010,105(25):252301
The first measurement of the charged-particle multiplicity density at midrapidity in Pb-Pb collisions at a center-of-mass energy per nucleon pair √ S NN = 2.76 TeV is presented. For an event sample corresponding to the most central 5% of the hadronic cross section, the pseudorapidity density of primary charged particles at midrapidity is 1584 ± 4(stat) ± 76(syst), which corresponds to 8.3 ± 0.4(syst) per participating nucleon pair. This represents an increase of about a factor 1.9 relative to pp collisions at similar collision energies, and about a factor 2.2 to central Au-Au collisions at √ S NN = 2.76 TeV. This measurement provides the first experimental constraint for models of nucleus-nucleus collisions at LHC energies. 相似文献
63.
Aamodt K Abelev B Quintana AA Adamová D Adare AM Aggarwal MM Rinella GA Agocs AG Salazar SA Ahammed Z Masoodi AA Ahmad N Ahn SU Akindinov A Aleksandrov D Alessandro B Molina RA Alici A Alkin A Aviña EA Alt T Altini V Altinpinar S Altsybeev I Andrei C Andronic A Anguelov V Anson C Antičić T Antinori F Antonioli P Aphecetche L Appelshäuser H Arbor N Arcelli S Arend A Armesto N Arnaldi R Aronsson T Arsene IC Asryan A Augustinus A Averbeck R Awes TC Aystö J Azmi MD Bach M Badalà A Baek YW 《Physical review letters》2010,105(25):252302
We report the first measurement of charged particle elliptic flow in Pb-Pb collisions at sqrt[S(NN)] =2.76 TeV with the ALICE detector at the CERN Large Hadron Collider. The measurement is performed in the central pseudorapidity region (|η|<0.8) and transverse momentum range 0.2
相似文献
64.
Bala Chandra Chenna Bidhan A. Shinkre Shweta Patel Samuel B. OwensJr. Gary M. Gray Sadanandan E. Velu 《Journal of chemical crystallography》2008,38(3):189-194
Abstract Synthesis, separation and X-ray crystal structures of E and Z isomers of 3-(2,5-dimethoxyphenyl)-2-(4-methoxyphenyl)acrylic acid are reported. Separation of E and Z isomers from a 1:1 mixture has been carried out by selective acidification of their sodium salts carefully controlling the
pH of the solution. The structures of E and Z isomers were confirmed by determining crystal structures of these isomers using single crystal X-ray diffraction. The E isomer crystallizes in the P21/c space group with a = 11.493(2) ?, b = 5.5456(11) ?, c = 24.900(5) ?, α = 90°, β = 92.36(3)°, γ = 90°, Z = 4. The Z isomer crystallizes in the P21/c space group with a = 10.192(2) ?, b = 12.893(3) ?, c = 13.948(3) ?, α = 90°, β = 92.18(3)°, γ = 90°, Z = 4. Details of the synthesis and structural characterization and X-ray crystal structure determination of the title compounds
are presented.
Index Abstract
Synthesis, Separation and Crystal Structures of
E
and
Z
Isomers of 3-(2,5-Dimethoxyphenyl)-2-(4-Methoxyphenyl)Acrylic Acid
Balachandra Chenna, Bidhan A. Shinkre, Shweta Patel, Samuel B. Owens Jr., Gary M. Gray, Sadanandan E. Velu*
Separation of E and Z isomers of 3-(2,5-dimethoxyphenyl)-2-(4-methoxyphenyl)acrylic acid from a 1:1 mixture has been carried out by selective acidification
of their sodium salts and the structures of the individual isomers have been determined by X-ray single crystal diffraction.
相似文献
65.
Renu Bala Poonam Kumari Sumit Sood Harshita Phougat Anil Kumar Karan Singh 《Journal of heterocyclic chemistry》2019,56(6):1787-1793
The conversion of aldehydes into carboxylic acids using oxidizing agents is a common protocol in transformation chemistry. An efficient oxidation strategy of transformation of pyrazole‐4‐aldehydes to the corresponding acids using vanadium catalysts in the presence of 30% H2O2 as an oxidant is described. The catalytic technology was successfully applied to a range of various 4‐formylpyrazoles, and plausible mechanism is also discussed. 相似文献
66.
Facile and efficient synthesis of sulfoxide esters using menthols as chiral auxiliary is described. Phenylthio/benzylthio/naphthylthioacetic esters act as an efficient substrate for chiral sulfoxides via oxidation in one step. The structural and stereochemical aspects of target product were established on the basis of various spectroscopic studies, namely FT-IR, NMR (1H NMR and 13C NMR) and elemental analysis. This method is simple, fast, convenient and very efficient. 相似文献
67.
Bishnu P. Biswal Sreeramulu Valligatla Mingchao Wang Tanmay Banerjee Nabil A. Saad Bala Murali Krishna Mariserla Naisa Chandrasekhar Daniel Becker Matthew Addicoat Irena Senkovska Reinhard Berger D. Narayana Rao Stefan Kaskel Xinliang Feng 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(21):6970-6974
Covalent organic frameworks (COFs) have garnered immense scientific interest among porous materials because of their structural tunability and diverse properties. However, the response of such materials toward laser‐induced nonlinear optical (NLO) applications is hardly understood and demands prompt attention. Three novel regioregular porphyrin (Por)‐based porous COFs—Por‐COF‐HH and its dual metalated congeners Por‐COF‐ZnCu and Por‐COF‐ZnNi—have been prepared and present excellent NLO properties. Notably, intensity‐dependent NLO switching behavior was observed for these Por‐COFs, which is highly desirable for optical switching and optical limiting devices. Moreover, the efficient π‐conjugation and charge‐transfer transition in ZnCu‐Por‐COF enabled a high nonlinear absorption coefficient (β=4470 cm/GW) and figure of merit (FOM=σ1/σo, 3565) value compared to other state‐of‐the‐art materials, including molecular porphyrins (β≈100–400 cm/GW), metal–organic frameworks (MOFs; β≈0.3–0.5 cm/GW), and graphene (β=900 cm/GW). 相似文献
68.
Bala Reddy Bheemareddy Mallikarjuna Pulipeta Pradeep Iyer 《Journal of carbohydrate chemistry》2019,38(1):1-19
The degree of monoclonal antibody galactosylation is known to affect complement-dependent cytotoxicity (CDC) activity by affecting C1q binding, suggesting that galactose is associated with CDC bioactivity. However, whether this association also exists under temperature stress conditions is not known. This study highlights the impact of variations in the terminal galactose content of an anti-CD20 monoclonal antibody on CDC bioactivity under high-temperature stress conditions compared with storage conditions at 2–8?°C. Drug product samples with a total galactose content of >38% showed stable CDC bioactivity at higher temperatures (45?°C), while those with 16% galactose content showed reduced CDC activity. 相似文献
69.
70.
We generalize a recently developed method for accelerated Monte Carlo calculation of path integrals to the physically relevant case of generic many-body systems. This is done by developing an analytic procedure for constructing a hierarchy of effective actions leading to improvements in convergence of N-fold discretized many-body path integral expressions from 1/N to 1/Np for generic p. In this Letter we present explicit solutions within this hierarchy up to level p=5. Using this we calculate the low lying energy levels of a two particle model with quartic interactions for several values of coupling and demonstrate agreement with analytical results governing the increase in efficiency of the new method. The applicability of the developed scheme is further extended to the calculation of energy expectation values through the construction of associated energy estimators exhibiting the same speedup in convergence. 相似文献