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11.
Study on phase diagrams and properties of solutions in ternary systems Li+,K+(Mg2+)/SO42--H2O at 25℃
LI Bing LI Jun FANG Chun-Hui WANG Qing-Zhong SONG Peng-ShengQinghai Institute of Salt Lakes Chinese Academy of Sciences Xining Qinghai China 《中国化学》1995,(2)
Solubilities of ternary systems Li+,K+/SO42--H2O (1) and Li+,Mg2+/SO42-H2O (2) were investigated by isothermal method at 25℃. Physico-chemical properties of solutions, such as density, refractive index, viscosity, conductivity and pH, were determined. Phase diagram of the system (1) consists of three solubility branches and three crystallization fields corresponding to K2SO4, Li2SO4.H2O and LiKSO4. LiKSO4 is an incongruent compound, and its transition point is estimated graphically to be 45.5-46.0℃. No solid solution of LiKSO4 with Li2SO4.H2O was found in the system. The system (2) is a simple eutonic type. Pitzer model of electrolyte solution was used to check the obtained solubilities. Data comparison gives good agreement. Two equations were used to correlate density, refractive index of the solution with its composition. Differences between measured and calculated values are less than 0.6% for density, 0.15% for the latter. 相似文献
12.
Inci Albayrak 《Journal of Mathematical Analysis and Applications》2007,328(1):414-428
In the present paper we investigate when Hausdorff matrices and generalized Hausdorff matrices, with the same mass function, are equivalent, as bounded operators on c and ?p. 相似文献
13.
A simple computer system designed for controlling voltammetric experiments has been implemented. The system connects a Hewlett-Packard 2100A minicomputer with a Texas Instruments 9900 microcomputer by means of a bidirectional serial transmission link. Experimental parameters are down-loaded from the host to the satellite which supervises the experiments at a remote location. The data collected are transmitted back to the host at 2400 baud for reduction and plotting. Through this division of labor, each system is used to its best advantage. Although the software developed is specifically for staircase voltammetry, the system hardware is of general-purpose design which is suited for other types of pulse experiment. 相似文献
14.
Two QSAR models have been identified that predict the affinity and selectivity of arylpiperazinyl derivatives for alpha1 and alpha2 adrenoceptors (ARs). The models have been specified and validated using 108 compounds whose structures and inhibition constants (Ki) are available in the literature [Barbaro et al., J. Med. Chem., 44 (2001) 2118; Betti et al., J. Med. Chem., 45 (2002) 3603; Barbaro et al., Bioorg. Med. Chem., 10 (2002) 361; Betti et al., J. Med. Chem., 46 (2003) 3555]. One hundred and forty-seven predictors have been calculated using the Cerius 2 software available from Accelrys. This set of variables exhibited redundancy and severe multicollinearity, which had to be identified and removed as appropriate in order to obtain robust regression models free of inflated errors for the beta estimates - so-called bouncing betas. Those predictors that contained information relevant to the alpha2 response were identified on the basis of their pairwise linear correlations with affinity (-log Ki) for alpha2 adrenoceptors; the remaining variables were discarded. Subsequent variable selection made use of Factor Analysis (FA) and Unsupervised Variable Selection (UzFS). The data was divided into test and training sets using cluster analysis. These two sets were characterised by similar and consistent distributions of compounds in a high dimensional, but relevant predictor space. Multiple regression was then used to determine a subset of predictors from which to determine QSAR models for affinity to alpha2-ARs. Two multivariate procedures, Continuum Regression (the Portsmouth formulation) and Canonical Correlation Analysis (CCA), have been used to specify models for affinity and selectivity, respectively. Reasonable predictions were obtained using these in silico screening tools. 相似文献
15.
Reem Aljanabi Lina Alsous Dima A. Sabbah Halise Inci Gul Mustafa Gul Sanaa K. Bardaweel 《Molecules (Basel, Switzerland)》2021,26(19)
Monoamine oxidases (MAOs) are oxidative enzymes that catalyze the conversion of biogenic amines into their corresponding aldehydes and ketones through oxidative deamination. Owing to the crucial role of MAOs in maintaining functional levels of neurotransmitters, the implications of its distorted activity have been associated with numerous neurological diseases. Recently, an unanticipated role of MAOs in tumor progression and metastasis has been reported. The chemical inhibition of MAOs might be a valuable therapeutic approach for cancer treatment. In this review, we reported computational approaches exploited in the design and development of selective MAO inhibitors accompanied by their biological activities. Additionally, we generated a pharmacophore model for MAO-A active inhibitors to identify the structural motifs to invoke an activity. 相似文献
16.
Sabriye Acikgoz Bukem Bilen Mustafa Muamer Demir Yusuf Ziya Menceloglu Yani Skarlatos Gulen Aktas Mehmet Naci Inci 《Optical Review》2008,15(2):84-90
Humidity induced change in the refractive index and thickness of the polyethylene glycol (PEG) coatings are in situ investigated for a range from 10 to 95%, using an optical waveguide spectroscopic technique. It is experimentally demonstrated
that, upon humidity change, the optical and swelling characteristics of the PEG coatings can be employed to build a plastic
fibre optic humidity sensor. The sensing mechanism is based on the humidity induced change in the refractive index of the
PEG film, which is directly coated onto a polished segment of a plastic optical fibre with dip-coating method. It is observed
that PEG, which is a highly hydrophilic material, shows no monotonic linear response to humidity but gives different characteristics
for various ranges of humidity levels both in index of refraction and in thickness. It undergoes a physical phase change from
a semi-crystalline structure to a gel one at around 80% relative humidity. At this phase change point, a drastic decrease
occurs in the index of refraction as well as a drastic increase in the swelling of the PEG film. In addition, PEG coatings
are hydrogenated in a vacuum chamber. It is observed that the hydrogen has a preventing effect on the humidity induced phase
change in PEG coatings. Finally, the possibility of using PEG coatings in construction of a real plastic fibre optic humidity
sensor is discussed. 相似文献
17.
S. González de la Hoz L. March E. Ros J. Sánchez G. Amorós F. Fassi A. Fernández M. Kaci A. Lamas J. Salt 《The European Physical Journal C - Particles and Fields》2008,54(4):691-697
In the ATLAS computing model the tiered hierarchy ranged from the Tier-0 (CERN) down to desktops or workstations (Tier-3).
The focus on defining the roles of each tiered component has evolved with the initial emphasis on the Tier-0 and Tier-1 definition
and roles. The various LHC (Large Hadron Collider) projects, including ATLAS, then evolved the tiered hierarchy to include
Tier-2’s (Regional centers) as part of their projects. Tier-3 centres, on the other hand, have been defined as whatever an
institution could construct to support their Physics goals using institutional and otherwise leveraged resources and therefore
have not been considered to be part of the official ATLAS computing resources. However, Tier-3 centres are going to exist
and will have implications on how the computing model should support ATLAS physicists. Tier-3 users will want to access LHC
data and simulations and will want to enable their resources to support their analysis and simulation work. This document
will define how IFIC (Instituto de Física Corpuscular de Valencia), after discussing with the ATLAS Tier-3 task force, should
interact with the ATLAS computing model, detail the conditions under which Tier-3 centres can expect some level of support
and set reasonable expectations for the scope and support of ATLAS Tier-3 sites. 相似文献
18.
Adams CJ Crawford PC Orpen AG Podesta TJ Salt B 《Chemical communications (Cambridge, England)》2005,(19):2457-2458
Thermal dehydrochlorination of crystalline 4-picolinium salts of [PtCl4]2- and [PdCl4]2- leads to formation of trans-[MCl2(4-picoline)2](M = Pt, Pd). 相似文献
19.
20.
This paper addresses an easy computation of the multiple components of the response to a sinusoidal input of a dual-rate linear time-invariant discrete system from the Bode diagram of LTI systems arising from a lifted representation. Based on those results, a generalized Bode diagram is suggested. Some new conclusions derived from this conceptual interpretation are introduced. This diagram provides a better insight in the frequency-response issues in multivariable control than the standard singular value decomposition of the lifted model. As an application, the output ripple suppression in a multirate control scheme is presented. 相似文献