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81.
We investigate some aspects of a generalized JC-model which include arbitrary forms of non-linearities of both the field and
the intensity-dependent atom-field coupling. We obtain an exactly analytic solution of the model, by means of which we identify
and numerically demonstrate the region of parameters where significantly large entanglement can be obtained. 相似文献
82.
Co-O and O-O bond stretching frequencies have been determined by oxygen isotopic substitution in a series of cobalt(III)—salen complexes. These all are of the binuclear type [Co(salen)L]2O2, with L being a basic ligand occupying an axial coordination position. The nature of the oxygen binding and the influence of the axial ligands are discussed. 相似文献
83.
Nour?ZidanEmail authorView authors OrcID profile 《International Journal of Theoretical Physics》2016,55(2):1274-1284
The dynamics of a mixed spin system governed by XXZ model in additional to an intrinsic decoherence is investigated. The behavior of quantum correlation and the degree of entanglement between the two subsystems is quantified by using measurement-induced disturbance and the negativity, respectively. It is shown that, the phenomena of long-lived entanglement appears for larger values of intrinsic decoherence parameters. The degree of entanglement and quantum correlation depend on the dimensions of subsystems which are pass through the external field and the initial states setting. We show that the negativity for some initial classes is more robust than the measurement-induced disturbance, while for some other initial classes the quantum correlations are more robust than entanglement. 相似文献
84.
In the event of a radioactive disaster, one of the biggest tasks is to estimate the radiation dosage received by people to
determine the actions of emergency response teams. The first and the most rapid screening method of internally contaminated
people in case of an emergency response is to perform in-vivo measurements for gamma-emitters. Development of virtual gamma-ray
calibration techniques will be critical for emergency invivo measurements because there are inadequate numbers of phantom
types to approximate all body shapes and sizes. The purpose of this project was to find a reliable way to estimate the efficiency
of gamma-systems using Monte Carlo computations, and to validate that efficiency by making measurements of a standard geometry.
Two geometries, a 5-ml ampoule and a Bottle Manikin Absorption (BOMAB) phantom head, spiked with 67Ga were used as standard geometries. The radioactive objects are measured at a number of distances from a high purity germanium
(HPGe) detector, and the experimental efficiency for our gamma-spectrometry system is determined. The same set of experiments
was then modeled using the Monte Carlo N-Particle Transport Code (MCNP). The conclusion of this project is that computationally
derived detector efficiency calibrations can be comparable to those derived experimentally from physical standards. 相似文献
85.
86.
Dissem Nour Kaur Prabhjyot Rana Love Karan Maris Thierry Duong Adam 《Transition Metal Chemistry》2021,46(4):283-290
Transition Metal Chemistry - One pot synthesis of a new mixed-ligand coordination polymer has been carried out by combining copper salt, macrocyclic ligand 1,4,8,11-tetraazacyclotetradecane... 相似文献
87.
Mohamed GG El-Dien FA Mohamed NA 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2007,68(5):1244-1249
A simple and rapid spectrophotometric method has been developed for the determination of tricyclic anti-depressant drugs such as trazodone (TZH), amineptine (APH) and amitriptyline (ATPH) hydrochlorides in pure form and in different pharmaceutical preparations. The charge transfer (CT) reaction between TZH, APH and ATPH as electron donors and TCNQ as electron acceptor was utilized for their spectrophotometric determination. The optimum experimental conditions, like time, temperature, stoichiometry, solvents, for the CT complex formation are established. The method permits the determination of TZH, APH and ATPH over a concentration range of 10-400, 10-440 and 10-300 microg ml(-1), respectively. The sensitivity (S) is found to be 0.09, 0.087 and 0.069 g cm(-2) for TZH, APH and ATPH, respectively. The SD values are found to be 0.146-0.293, 0.154-0.285 and 0.091-0.212 and RSD values are 0.142-1.92, 0.297-1.92 and 0.212-0.915 for TZH, APH and ATPH, respectively. The low values of the relative standard deviation indicate the high accuracy and precision of the method. The mean recovery values obtained together with a high correlation coefficient values, amount in the range 98-101.5, 98.7-102.9 and 93-101.9 for TZH, APH and ATPH, respectively. The method is applicable for the assay of the investigated drugs in different dosage forms and the results are in good agreement with those obtained by the official method. 相似文献
88.
89.
Mohsen K. A. Regal El-Hady Rafat Nour E. A. Abd El-Sattar 《Journal of heterocyclic chemistry》2020,57(3):1173-1182
A string of novel heterocyclic mono azo dyes were synthesized and their utilization in dyeing different fabrics as wool and nylon were discussed. Thienopyridine azo dyes 4 and 6 were prepared by reaction of chloro acetamidederivative 2 with diamino compounds to yield 3 and 5 , followed by reaction with NaNO2/HCl and coupling with nucleophilic reagent. One-pot reaction of chloro acetamide 2 with ammonium thiocyanat in solvent ethanol gave the unexpected thienopyrimidine derivative 7 , which contain two active sites, the former is primary amine that was able to form diazonium salt that coupled with N,N-dimethylaniline, resorcinol, and/or self-coupling to afford the azo dyes 8-10 , and the latter is active methylene group that underwent coupling with different diazonium salts to give the azo thienopyrimidine derivative dye 11-15 . The dyeing performance of these azo dyes had been investigated in terms of their dyeing behavior and fastness properties on different fabrics. Results showed that the color strength (K/S) values, as well as, washing, rubbing, and resistance to acid, alkali and light showed high efficiency of these heterocyclic mono azo dyes to dye wool rather than nylon fibers. 相似文献
90.
2-Functionalised aromatic monoaldehydes were synthesised in good to excellent yields by reacting 4-bromo-2-fluorobenzaldehyde with different secondary amines and phenol. The Suzuki-coupling reaction of the newly functionalised aromatic monoaldehydes with 4-formylphenylboronic acid afforded the corresponding 2-functionalised-4,4'-biphenyldialdehydes in good yields (47-85%). The [3+3]-cyclocondensation reactions of the 2-functionalised-4,4'-biphenyldialdehydes with (1R,2R)-1,2-diaminocyclohexane afforded a mixture of regioisomeric C(3)-symmetrical and non-symmetrical trianglimines. Reduction of the C(3)-symmetrical and the non-symmetrical trianglimines with NaBH(4) in a mixture of THF and MeOH afforded the corresponding trianglamines in high yields. 相似文献