80 research outputs found
Application of the Conduct-like Screening Models for Real Solvent and Segment Activity Coefficient for the Predictions of Partition Coefficients and Vapor–Liquid and Liquid–Liquid Equilibria of Bio-oil-Related Mixtures
The 1-octanol/water partition coefficients (log <i>P</i>) at 298.15 K and the vapor–liquid and liquid–liquid
equilibria (VLE and LLE) of biofuel-related mixtures have been predicted
with four different thermodynamic models: conduct-like screening models
for real solvent (COSMO-RS), conduct-like screening models for segment
activity coefficient (COSMO-SAC) (2002 version), modified COSMO-SAC
(2006 version), and universal functional activity coefficient (UNIFAC).
The 2002 version of COSMO-SAC gives more reasonable predictions for
log <i>P</i> for most investigated mixtures than the other
two approaches when appropriate molecular geometries are chosen for
the computation of the σ profiles. However, the COSMO-RS model
gives better predictions for VLE pressures and vapor-phase compositions
for biofuel-related mixtures, as well as for the LLE of the 1-octanol
+ water and furfural + water mixtures. The accuracy of the models
for the predictions of the partition coefficients and VLE may be improved
by changing the molecular conformations used to generate the σ
profiles. Generally, the three COSMO-based models give better predictions
than UNIFAC for log <i>P</i> and VLE of the investigated
systems and can be applied to predict the thermodynamic properties
of the biofuel-related mixtures especially when no experimental data
are available
Integrated Operation and Cyclic Scheduling Optimization for an Ethylene Cracking Furnaces System
Multiple
cracking furnaces in an ethylene plant run in parallel
to produce ethylene, propylene, and other products from different
hydrocarbon feedstocks. Because both coke formation in radiant coils
and change of operation conditions with time have significant effects
on the performance of cracking furnaces, it is better for the cyclic
scheduling to be simultaneously optimized with the operation conditions.
To match this real requirement, a mixed-integer dynamic optimization
(MIDO) problem is presented for the optimization of both operation
conditions and cyclic scheduling simultaneously, through which the
optimal assignment, the processing time, the subcycle number, and
the optimal operation conditions of different feeds in different cracking
furnaces are determined at the same time. To solve the MIDO problem,
it is discretized and converted into a large scale mixed-integer nonlinear
programming (MINLP) problem. The two scheduling cases of a cracking
furnaces system are illustrated showing a remarkable increase in the
economic performance as compared with that of the traditional method
Modular Synthesis of α‑Aryl-α-Heteroaryl α‑Amino Acid Derivatives via a Copper-Catalyzed Cross-Dehydrogenative-Coupling Reaction Using Air as the Sole Oxidant
A novel
copper-catalyzed cross-dehydrogenative-coupling (CDC) process
of arylglycine derivatives with N-heteroarenes for the straightforward
synthesis of α-aryl-α-heteroaryl α-amino acid scaffolds
has been successfully developed. This protocol exhibits a broad substrate
scope with good functional group compatibility by utilizing air as
the sole oxidant. The use of the reaction is also displayed through
the late-stage functionalization of arylglycines bearing natural compounds
or drug motifs
Classification of Time Series Gene Expression in Clinical Studies via Integration of Biological Network
<div><p>The increasing availability of time series expression datasets, although promising, raises a number of new computational challenges. Accordingly, the development of suitable classification methods to make reliable and sound predictions is becoming a pressing issue. We propose, here, a new method to classify time series gene expression via integration of biological networks. We evaluated our approach on 2 different datasets and showed that the use of a hidden Markov model/Gaussian mixture models hybrid explores the time-dependence of the expression data, thereby leading to better prediction results. We demonstrated that the biclustering procedure identifies function-related genes as a whole, giving rise to high accordance in prognosis prediction across independent time series datasets. In addition, we showed that integration of biological networks into our method significantly improves prediction performance. Moreover, we compared our approach with several state-of–the-art algorithms and found that our method outperformed previous approaches with regard to various criteria. Finally, our approach achieved better prediction results on early-stage data, implying the potential of our method for practical prediction.</p> </div
Classification accuracies of different discretization methods for Baranzini dataset and Goertsches dataset: average (AVG) and standard deviation (SD).
<p>Classification accuracies of different discretization methods for Baranzini dataset and Goertsches dataset: average (AVG) and standard deviation (SD).</p
Capturing Thermodynamic Behavior of Ionic Liquid Systems: Correlations with the SWCF-VR Equation
An equation of state for square-well chain fluids with
variable well-width range (SWCF-VR EoS) [Li et al. <i>Fluid Phase
Equilib.</i> <b>2009</b>, <i>276</i>, 57] was
applied to ionic liquid (IL) systems. ILs were treated as the square-well
chain with hydrogen bonding. The corresponding association parameters
were given according to our previous work [He et al. <i>Fluid
Phase Equilib.</i> <b>2011</b>, <i>302</i>, 139].
The nonassociation parameters were obtained by correlating the experimental
liquid densities. Excellent agreements were observed between experimental
and theoretical results for pure ILs, and the molecular parameters
were linearly correlated with the molecular masses of the [C<sub><i>n</i></sub>mim]Â[NTf<sub>2</sub>] members (<i>n</i> = 2, 3, ..., 8, 10). It is found that the other thermodynamic properties
such as the vapor pressure and the enthalpy of vaporization, etc.,
can be reasonably predicted by using the obtained molecular parameters.
The phase behavior of the binary systems containing ILs was well-represented
with a simple mixing rule. For the vapor–liquid equilibria
(VLE) of a system of volatile fluid + IL at low pressures, a temperature-independent
binary interaction parameter was adopted. Satisfactory results were
achieved for both the self- and cross-associating systems. The influence
of temperature on the binary interaction parameters was taken into
account in the correlation for the gas–liquid equilibria (GLE)
of CO<sub>2</sub> + IL mixtures and liquid–liquid equilibria
(LLE) of IL-containing systems. For CO<sub>2</sub> + IL mixtures,
the multipolar interactions between like and unlike molecules, and
the cross-association between CO<sub>2</sub> and IL molecules were
neglected to reduce the computational complexity, and the correlated
results agree well with the experimental ones over a wide range of
temperatures and pressures. The LLE of alkanol + IL systems were acceptably
reproduced with moderate deviations between the experimental and calculated
mass fractions. In the water-rich phase of water + IL with LLE, the
neglect of electrostatic interaction caused correlated results to
deviate from experimental ones greatly
Precision, Recall and F-measure of different classification approaches.
<p>The bars and error ticks represent mean values and standard deviations respectively. (A) shows the result for Baranzini dataset. (B) shows the result for Goertsches dataset.</p
Cdc6 depletion reverses the PTX-induced Cdk1 inactivation in Hela cells.
<p>Hela cells were treated with PTX (30 nM) combination with or without Cdc6 RNAi or NCTD (30 μM) as described in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0162633#pone.0162633.g007" target="_blank">Fig 7</a>. Cdc6, pCdk1 and Rad 21 were examined by Western Blotting. GAPDH was used as loading control. The protein levels are expressed as optical density fold difference related to GAPDH (relative OD). Three independent experiments were performed, *<i>P</i><0.05 as compared to PTX group.</p
Classification accuracies of PPI-SVM-KNN with the change of parameter C.
<p>The bars and error ticks represent mean values and standard deviations respectively. (A) shows the result for Baranzini dataset. (B) shows the result for Goertsches dataset.</p
Classification accuracies of distinct classification methods for Baranzini dataset and Goertsches dataset: average (AVG) and standard deviation (SD).
<p>Classification accuracies of distinct classification methods for Baranzini dataset and Goertsches dataset: average (AVG) and standard deviation (SD).</p
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