The synthesis of terpene esters was studied using a
Candida rugosa lipase encapsulated in an AOT-reverse-micellar solution. Three terpene alcohols, geraniol, citronellol, and menthol and three ...triacylglycerols, tributyrin, tricaprylin, and triacetin were investigated as substrates for the transesterification. Geraniol and tributyrin were found to be the best substrates to form the terpene ester in a water/AOT/isooctane reverse micellar solution. To obtain higher conversion yields of geraniol, the reaction parameters such as solvent type, enzyme and surfactant concentration, pH,
W
O, and substrate concentration and ratio were investigated. It was concluded that enzyme deactivation in the reverse micelle was the main factor leading to suboptimal conversions. For a geraniol concentration of 100 m
m, the highest extent of conversion of geraniol in a 500 m
m AOT-reverse-micellar solution at pH 7 and
W
O = 11 at 30°C was about 70%; however, the stability of the entrapped lipase under these conditions was low; the activity level for the
C. rugosa lipase entrapped in reverse micelles dropped precipitously to about 10% within 24 h.
The production cross section of inclusive isolated photons has been measured by the ALICE experiment at the CERN LHC in pp collisions at a centre-of-momentum energy of Formula omitted 7 TeV. The ...measurement is performed with the electromagnetic calorimeter EMCal and the central tracking detectors, covering a range of Formula omitted in pseudorapidity and a transverse momentum range of Formula omitted. The result extends the Formula omitted coverage of previously published results of the ATLAS and CMS experiments at the same collision energy to smaller Formula omitted. The measurement is compared to next-to-leading order perturbative QCD calculations and to the results from the ATLAS and CMS experiments. All measurements and theory predictions are in agreement with each other.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
We present a study of the inclusive charged-particle transverse momentum ( Formula omitted) spectra as a function of charged-particle multiplicity density at mid-pseudorapidity, Formula omitted, in ...pp collisions at Formula omitted and 13 TeV covering the kinematic range Formula omitted and Formula omitted GeV/c. The results are presented for events with at least one charged particle in Formula omitted (INEL Formula omitted). The Formula omitted spectra are reported for two multiplicity estimators covering different pseudorapidity regions. The Formula omitted spectra normalized to that for INEL Formula omitted show little energy dependence. Moreover, the high- Formula omitted yields of charged particles increase faster than the charged-particle multiplicity density. The average Formula omitted as a function of multiplicity and transverse spherocity is reported for pp collisions at Formula omitted TeV. For low- (high-) spherocity events, corresponding to jet-like (isotropic) events, the average Formula omitted is higher (smaller) than that measured in INEL Formula omitted pp collisions. Within uncertainties, the functional form of Formula omitted is not affected by the spherocity selection. While EPOS LHC gives a good description of many features of data, PYTHIA overestimates the average Formula omitted in jet-like events.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The ALICE Collaboration has measured the energy dependence of exclusive photoproduction of Formula omitted vector mesons off proton targets in ultra-peripheral p-Pb collisions at a centre-of-mass ...energy per nucleon pair Formula omitted TeV. The e Formula omittede Formula omitted and Formula omitted decay channels are used to measure the cross section as a function of the rapidity of the Formula omitted in the range Formula omitted, corresponding to an energy in the Formula omittedp centre-of-mass in the interval Formula omitted GeV. The measurements, which are consistent with a power law dependence of the exclusive Formula omitted photoproduction cross section, are compared to previous results from HERA and the LHC and to several theoretical models. They are found to be compatible with previous measurements.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The measurements of the production of prompt Formula omitted, Formula omitted, Formula omitted, and Formula omitted mesons in proton-proton (pp) collisions at Formula omitted with the ALICE detector ...at the Large Hadron Collider (LHC) are reported. D mesons were reconstructed at mid-rapidity ( Formula omitted) via their hadronic decay channels Formula omitted, Formula omitted, Formula omitted, Formula omitted, and their charge conjugates. The production cross sections were measured in the transverse momentum interval Formula omitted for Formula omitted, Formula omitted for Formula omitted and Formula omitted, and in Formula omitted for Formula omitted mesons. Thanks to the higher integrated luminosity, an analysis in finer Formula omitted bins with respect to the previous measurements at Formula omitted was performed, allowing for a more detailed description of the cross-section Formula omitted shape. The measured Formula omitted-differential production cross sections are compared to the results at Formula omitted TeV and to four different perturbative QCD calculations. Its rapidity dependence is also tested combining the ALICE and LHCb measurements in pp collisions at Formula omitted. This measurement will allow for a more accurate determination of the nuclear modification factor in p-Pb and Pb-Pb collisions performed at the same nucleon-nucleon centre-of-mass energy.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The pseudorapidity density of charged particles, Formula omitted, in p-Pb collisions has been measured at a centre-of-mass energy per nucleon-nucleon pair of Formula omitted = 8.16 TeV at ...mid-pseudorapidity for non-single-diffractive events. The results cover 3.6 units of pseudorapidity, Formula omitted. The Formula omitted value is Formula omitted at Formula omitted. This quantity divided by Formula omitted / 2 is Formula omitted, where Formula omittedis the average number of participating nucleons, is 9.5% higher than the corresponding value for p-Pb collisions at Formula omitted = 5.02 TeV. Measurements are compared with models based on different mechanisms for particle production. All models agree within uncertainties with data in the Pb-going side, while HIJING overestimates, showing a symmetric behaviour, and EPOS underestimates the p-going side of the Formula omitted distribution. Saturation-based models reproduce the distributions well for Formula omitted. The Formula omitted is also measured for different centrality estimators, based both on the charged-particle multiplicity and on the energy deposited in the Zero-Degree Calorimeters. A study of the implications of the large multiplicity fluctuations due to the small number of participants for systems like p-Pb in the centrality calculation for multiplicity-based estimators is discussed, demonstrating the advantages of determining the centrality with energy deposited near beam rapidity.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
First results on Formula omitted, Formula omitted and K/p fluctuations are obtained with the ALICE detector at the CERN LHC as a function of centrality in Formula omitted collisions at Formula ...omitted. The observable Formula omitted, which is defined in terms of the moments of particle multiplicity distributions, is used to quantify the magnitude of dynamical fluctuations of relative particle yields and also provides insight into the correlation between particle pairs. This study is based on a novel experimental technique, called the Identity Method, which allows one to measure the moments of multiplicity distributions in case of incomplete particle identification. The results for Formula omitted show a change of sign in Formula omitted from positive to negative towards more peripheral collisions. For central collisions, the results follow the smooth trend of the data at lower energies and Formula omitted exhibits a change in sign for Formula omitted and K/p.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
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