Synthesis and fluorescent properties of Eu and Tb complexes with a series of new diamide ligands

A series of new diamide ligands were introduced into the complexes of Eu(NO₃)₃ and Tb(NO₃)₃ so as to improve the fluorescent properties. The fluorescent properties of the resulting complexes were investigated. It was found that the complexes subject to the excitation of UV light showed characteristic emission of europium and terbium ions, in particular, the Tb complexes had very much intense fluorescence.     

Development of Whole and Ground Seed Near-Infrared Spectroscopy Calibrations for Oil,Protein, Moisture,and Fatty Acids in Salvia hispanica

Chia (Salvia hispanica) is an ancient crop that has experienced an agricultural resurgence in recent decades owing to the high omega 3 fatty acid (ω-3) content of the seeds and good production potential. Analysis of 563 lots of chia grown in Kentucky and 10 lots from Arizona, Australia, Mexico, and Peru was performed. All of these lots were assessed for fatty acid, oil, and protein content, while a subset of 120 samples were assessed for amino acids, fiber, minerals, and trace elements. The mean oil content was 31.3%, ranging from 21.4% to 35.3%. The protein content averaged 22.8%, ranging from 18.2% to 28.2%, and the ω-3 FA α-linolenic acid (ALA) averaged 61.3%, ranging from 33.9% to 69.9%. Using these seed lots, nondestructive near-infrared spectroscopy (NIRS) calibrations were developed for whole and ground seed oil, protein, moisture, and the six major fatty acids. The R² and SE of cross-validation (SECV) values for oil were 0.78 and 0.95, respectively, while those for protein were 0.75 and 1.05, respectively. The NIRS calibrations for fatty acid had R² and SECV greater than 0.6 and less than 10% of actual values for all major fatty acids, respectively. An R² of 0.99 was established for moisture content of whole seeds within the range of 3–10% moisture content. The precision and accuracy of these calibrations is adequate for use by breeders, growers, and food quality experts to quantitatively assess these major constituents without the need for costly and time-consuming chemical analysis.     

L-Moments Based Calibrated Variance Estimators Using Double Stratified Sampling

Variance is one of the most vital measures of dispersion widely employed in practical aspects. A commonly used approach for variance estimation is the traditional method of moments that is strongly influenced by the presence of extreme values, and thus its results cannot be relied on. Finding momentum from Koyuncu’s recent work, the present paper focuses first on proposing two classes of variance estimators based on linear moments (L-moments), and then employing them with auxiliary data under double stratified sampling to introduce a new class of calibration variance estimators using important properties of L-moments (L-location, L-cv, L-variance). Three populations are taken into account to assess the efficiency of the new estimators. The first and second populations are concerned with artificial data, and the third populations is concerned with real data. The percentage relative efficiency of the proposed estimators over existing ones is evaluated. In the presence of extreme values, our findings depict the superiority and high efficiency of the proposed classes over traditional classes. Hence, when auxiliary data is available along with extreme values, the proposed classes of estimators may be implemented in an extensive variety of sampling surveys.     

Un nouvel outil pour l'étude des interactions tôle–outil–lubrificant: Le test en cadence

In order to obtain a formed part, free from any defect such as necking, failure, galling marks or bad surface appearance, it is increasingly important to control the deep interactions between the steel sheet, the lubricant and the tooling. Another fundamental requirement for the industry is an ever growing productivity which implies a better stability of the process, also allowing an increase in the number of parts drawn per minute. Recently, RDCS has developed a new friction set-up able to study the behaviour of the steel sheet, coated or not, during its short contact with the tooling in the presence of a lubricant. Series of hundreds of samples are successively drawn. First results are interpreted.     

Adaptation et fatigue de composants mécaniques sous chargement complexe

Shakedown and fatigue of mechanical parts under complex loading. Mechanical strength of parts used for guidance or power transmission (bearings, gears, etc.) is of primary importance. However, loading cycles including variable high contact stresses are particularly complex. Reliability estimation of life for such components implies initial state evaluation, and elastic shakedown capabilities under service loading. Whenever elastic shakedown is achieved, probability of crack initiation should be estimated, as well as time to crack initiation (life duration). Finally, propagation of these cracks should be predicted. Our work has dealt with the two first points, elastic shakedown and crack initiation. A fatigue damage accumulation law has been calculated and tested. We have used original scientific methods to deal with these problems and it has resulted in a PC software package using the finite element method joined to analytic calculations: A2DF6S-SC software for ball bearings, taking into account the 3D effects of rolling, sliding and spinning for ball on rings contacts, and A2DF (2D) for other components.