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排序方式: 共有563条查询结果,搜索用时 15 毫秒
1.
This study tried to investigate, by the power comsumption technique, the influence of the powder's and solvent's properties on wet granulation.
It could be shown that the required amount of granulation liquid decreases when the particle size of the powder to be granulated increases. This relationship is however only true when the particle size distribution of the powder to be granulated is rather narrow.
Powders having the same solubility in different solvents require the same optimal liquid quantity for granulation, but the properties of resulting granules depend on surface tension and wetting properties of the solvent.
When the powder to be granulated contains crystallisation water, the temperature rising in the mixer can be sufficient to liberate this water, which must be taken into account in the optimal granulation liquid requirement.
The effect of a macromolecular binder (PVP, HPMC) has also been studied: the optimal liquid quantity required changes with the kind of binder used and the manufacturing process (binder used in solution or added as dry powder).
It was also shown that in the case of lactose, the optimal quantity of PVP or HPMC can be determined from the power consumption records and from the granules friability studies 相似文献
It could be shown that the required amount of granulation liquid decreases when the particle size of the powder to be granulated increases. This relationship is however only true when the particle size distribution of the powder to be granulated is rather narrow.
Powders having the same solubility in different solvents require the same optimal liquid quantity for granulation, but the properties of resulting granules depend on surface tension and wetting properties of the solvent.
When the powder to be granulated contains crystallisation water, the temperature rising in the mixer can be sufficient to liberate this water, which must be taken into account in the optimal granulation liquid requirement.
The effect of a macromolecular binder (PVP, HPMC) has also been studied: the optimal liquid quantity required changes with the kind of binder used and the manufacturing process (binder used in solution or added as dry powder).
It was also shown that in the case of lactose, the optimal quantity of PVP or HPMC can be determined from the power consumption records and from the granules friability studies 相似文献
2.
The selective recovery of vanadium from an effluent of a manufacturing process for titanium white (oxide) has been made. The process retained is based on the partial neutralization of the effluent by means of calcium carbonate and on the separation of metal hydroxides from calcium sulfate and the solution. The hydroxides are thereafter calcined in the presence of a sodium salt, so that sodium vanadate may then be extracted by washing with water. Vanadium is finally precipitated by the addition of ammonium chloride or pH adjustment. The experimental results obtained in the laboratory study of the effluent neutralization, the calcination and leaching of the hydroxides and the vanadium precipitation are presented and discussed. The yields obtained in the various stages and their interdependance are also discussed. 相似文献
3.
J Paris 《Canadian Metallurgical Quarterly》1995,3(1):10-17
This review will examine issues related to the validity of memories of child abuse in patients with borderline personality disorder (BPD). A large body of research has shown that all memories are distorted by cognitive schema, and that "recovered memories" may be particularly unreliable. Empirical findings on trauma in BPD will be reviewed, as well as the difficulties in verifying trauma histories. Evidence will be examined suggesting that borderline patients have a distorted perception of interpersonal events. Clinical recommendations will be made for the evaluation of memories of abuse in patients with BPD. 相似文献
4.
M. Carmen Clemente Fernando Ruiz-Vega Pablo Otero José F. Paris 《Wireless Personal Communications》2014,78(2):1231-1248
In this paper the performance of a wireless communications system over shallow underwater acoustic channels is investigated when adaptive modulation and coding techniques with receiver diversity are used. It is assumed that the communication system experiences Ricean shadowed fading. We obtain the analytical figures of the proposed rate-adaptive transmission schemes, emphasizing in the spectral efficiency and the average bit error rate. These analytical expressions are compared to Monte-Carlo simulations corroborating the analytical results. 相似文献
5.
Orsak G.C. Paris B.-P. 《IEEE transactions on information theory / Professional Technical Group on Information Theory》1995,41(1):188-203
The problem of designing and analyzing suboptimal detectors via statistical distance measures is considered. As a preliminary result, we show that only the minimum and maximum probability of error are valid measures of discrimination between the input statistics. This result would seem then to imply that the use of distance measures in this context can be inappropriate. However, to overcome this apparent obstacle, we demonstrate explicit relationships between various f-divergences and the loss in performance of an arbitrary detector relative to the optimal detector. In particular, we establish both upper and lower bounds on the performance loss of a suboptimal detector in terms of the “distance” between the pertinent statistics of both the optimal and suboptimal detectors. While designing detectors by minimizing these upper bounds can be an elusive task, in many practical cases, the lower bound presented herein holds with equality. In this case, minimizing the separation of the output statistics of the detector with respect to a particular f-divergence equivalently minimizes the resulting probability of error of the detector. To facilitate design, other researchers have established conditions under which one may design arbitrary detection strategies with respect to a specific f-divergence (Kullback-Leibler distance being a principal example). We extend this approach by deriving necessary and sufficient conditions under which one may design detection strategies with respect to an arbitrarily chosen f-divergence. Thus when these conditions are met, one may optimize a detector with respect to the most analytically tractable distance measure to obtain the minimum probability of error detector over a selected class of detection strategies. Examples demonstrating the utility of this theory for the problem of designing optimal linear detectors and optimal signal sets are presented 相似文献
6.
Tzinis Efthymios Wang Zhepei Jiang Xilin Smaragdis Paris 《Journal of Signal Processing Systems》2022,94(2):245-259
Journal of Signal Processing Systems - Recent progress in audio source separation led by deep learning has enabled many neural network models to provide robust solutions to this fundamental... 相似文献
7.
Hadjazi M. Palmier J.F. Sibille A. Wang H. Paris E. Mollot F. 《Electronics letters》1993,29(8):648-649
The negative differential conductance originating from miniband negative effective mass has been characterised at high frequencies in two GaAs/AlAs superlattice devices. High reflection gains reaching 10 dB at 38 GHz have been observed up to 60 GHz. These results demonstrate the excellent potentialities of superlattices for millimetre-wave oscillator applications.<> 相似文献
8.
With a narrow-beam field microwave scatterometer having a variable slant range and a small slant-range resolution, investigators can estimate the distribution of backscattering sources in a medium as a function of slant range. From this, they can calculate the backscattering coefficient. With less confidence, they can estimate the volume extinction coefficient, the volume density of backscattering cross sections, the transmittance, and the backscattering coefficient of a semiinfinite medium with the same volumetric microwave properties. These parameters allow one to understand the interactions of microwaves with media such as vegetation canopies with their substrates. 相似文献
9.
10.
Debora Paris Letizia Palomba Virginia Mirra Melissa Borrelli Adele Corcione Francesca Santamaria Mauro Maniscalco Andrea Motta 《International journal of molecular sciences》2020,21(22)
Nuclear-magnetic-resonance (NMR) profiling of exhaled breath condensate (EBC) provides insights into the pathophysiology of bronchiectasis by identifying specific biomarkers. We evaluated whether NMR-based metabolomics discriminates the EBC-derived metabolic phenotypes (“metabotypes”) of 41 patients with non-cystic fibrosis (nCF) bronchiectasis of various etiology [24 subjects with Primary Ciliary Dyskinesia (PCD); 17 patients with bronchiectasis not associated with PCD (nCF/nPCD)], who were compared to 17 healthy subjects (HS). NMR was used for EBC profiling, and Orthogonal Projections to Latent Structures with partial least-squares discriminant analysis (OPLS-DA) was used as a classifier. The results were validated by using the EBC from 17 PCD patients not included in the primary analysis. Different statistical models were built, which compared nCF/nPCD and HS, PCD and HS, all classes (nCF/nPCD-PCD-HS), and, finally, PCD and nCF/nPCD. In the PCD-nCF/nPCD model, four statistically significant metabolites were able to discriminate between the two groups, with only a minor reduction of the quality parameters. In particular, for nCF/nPCD, acetone/acetoin and methanol increased by 21% and 18%, respectively. In PCD patients, ethanol and lactate increased by 25% and 28%, respectively. They are all related to lung inflammation as methanol is found in the exhaled breath of lung cancer patients, acetone/acetoin produce toxic ROS that damage lung tissue in CF, and lactate is observed in acute inflammation. Interestingly, a high concentration of ethanol hampers cilia beating and can be associated with the genetic defect of PCD. Model validation with 17 PCD samples not included in the primary analysis correctly predicted all samples. Our results indicate that NMR of EBC discriminates nCF/nPCD and PCD bronchiectasis patients from HS, and patients with nCF/nPCD from those with PCD. The metabolites responsible for between-group separation identified specific metabotypes, which characterize bronchiectasis of a different etiology. 相似文献