Behaviour of fractional loop delay zero crossing digital phase locked loop (FR-ZCDPLL)

This article analyses the performance of the first-order zero crossing digital phase locked loops (FR-ZCDPLL) when fractional loop delay is added to loop. The non-linear dynamics of the loop is presented, analysed and examined through bifurcation behaviour. Numerical simulation of the loop is conducted to proof the mathematical analysis of the loop operation. The results of the loop simulation show that the proposed FR-ZCDPLL has enhanced the performance compared to the conventional zero crossing DPLL in terms of wider lock range, captured range and stable operation region. In addition, extensive experimental simulation was conducted to find the optimum loop parameters for different loop environmental conditions. The addition of the fractional loop delay network in the conventional loop also reduces the phase jitter and its variance especially when the signal-to-noise ratio is low.     

EGFR and COX-2 Dual Inhibitor: The Design,Synthesis, and Biological Evaluation of Novel Chalcones

For most researchers, discovering new anticancer drugs to avoid the adverse effects of current ones, to improve therapeutic benefits and to reduce resistance is essential. Because the COX-2 enzyme plays an important role in various types of cancer leading to malignancy enhancement, inhibition of apoptosis, and tumor-cell metastasis, an indispensable objective is to design new scaffolds or drugs that possess combined action or dual effect, such as kinase and COX-2 inhibition. The start compounds A1 to A6 were prepared through the diazo coupling of 3-aminoacetophenone with a corresponding phenol and then condensed with two new chalcone series, C7–18. The newly synthesized compounds were assessed against both COX-2 and epidermal growth factor receptor (EGFR) for their inhibitory effect. All novel compounds were screened for cytotoxicity against five cancer cell lines. Compounds C9 and G10 exhibited potent EGFR inhibition with IC₅₀ values of 0.8 and 1.1 µM, respectively. Additionally, they also displayed great COX-2 inhibition with IC₅₀ values of 1.27 and 1.88 µM, respectively. Furthermore, the target compounds were assessed for their cytotoxicity against pancreatic ductal cancer (Panc-1), lung cancer (H-460), human colon cancer (HT-29), human malignant melanoma (A375) and pancreatic cancer (PaCa-2) cell lines. Interestingly, compounds C10 and G12 exhibited the strongest cytotoxic effect against PaCa-2 with average IC₅₀ values of 0.9 and 0.8 µM, respectively. To understand the possible binding modes of the compounds under investigation with the receptor cites of EGFR and COX-2, a virtual docking study was conducted.     

The 1,4-diaza[2.2.2] Bicyclooctane—hydrogen peroxide complex as a source of anhydrous hydrogen peroxide: the preparation of bis(trialkylsilyl) peroxides

The hazard and inconvenience of storing and handling concentrated hydrogen peroxide can be avoided by using instead the solid $\text{1}\text{2}$ complex which 1,4-diazabicyclo[2.2.2] octane forms with hydrogen peroxide, it reacts with trialkylchlorosilanes to give bis(trialkylsilyl) peroxides in good yield.     

Resource-based direct manipulation: a user-centric visual interface for operational customization of future smart appliances

Telecommunication Systems - In the current era of IoT, home appliances like dishwashers, washing machines, and coffee makers, etc. are being equipped with internet access and sensing resources to...     

Transport of99mTc across TBP-kerosene oil supported liquid membranes

Transport of^99mTc across tri-n-butylphosphate (TBP) kerosene oil supported liquid membranes (SLM) has been studied under various conditions. Presence of dichromate ions helps avoid activity scavenging effects. Concentration increase of TBP, the complexing carrier used in the present study has a positive effect on flux (J) and permeability (P) of these ions, as up to 2.87M there is an increase in J and P values. HCl concentration in the feed solution increases J and P with their maximum values at 2.5–3.0M HCl in the feed. Above this concentration there is a decrease in flux and permeability of^99mTc(VII) ions. The given ions are stripped with LiCl or NaCl solutions but more with NaOH. The optimum conditions of transport of the given ions are 2.5M HCl concentration in the feed, 2.87M TBP concentration in the membrane and 1M NaOH concentration in the strip solution. Equations have been developed to indicate the relation between flux, J, viscosity, of TBP in organic membrane phase, temperature, T, [H⁺], in the aqueous feed solutions and Tc ion concentration in the feed solution. Based on P, the values determined from liquid membrane experiments, the quantitative flux values of Tc(VII) ions were also determined as a function of TBP concentration in the membranes, and HCl and Tc concentration in the feed solution using the given equations. This experimental technique provides quantitative results from trace level activity transfer experiments.     

Experimental and Computational Studies of the Copper Borate Complexes [(NHC)Cu(HBEt3)] and [(NHC)Cu(HB(C6F5)3)]

The synthesis of the Cu‐borate complexes [(6Mes)Cu(HBR₃)] featuring the unusual [HBEt₃]^? ( 5 ) and [HB(C₆F₅)₃]^? ( 6 ) ligands is described. Experimental and computational studies show both compounds feature a direct Cu–H interaction, but that while 5 is two‐coordinate, 6 displays an additional, stabilizing Cu–C_ipso(C₆F₅) interaction.     

Efficient synthesis of ethyl 3-alkyl-4-oxo-2-thioxo-1,3-thiazolane-5-carboxylates from the reaction of carbon disulfide and primary amines in the presence of diethyl 2-chloromalonate

An efficient synthesis of ethyl 3-alkyl-4-oxo-2-thioxo-1,3-thiazolane-5-carboxylates via reaction of primary amines with CS₂ in the presence of diethyl 2-chloromalonate is described.