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The current study offers a metal-free, direct, and successful synthesis technique for a new series of quinolinone and benzo[d][1,3]oxazine, along with an assessment of their biological activities. Heteroannulation of anthranilic acid with carbonyl-containing chemicals (aroyl pyruvate, ethyl acetoacetatete, maleic anhydride, and ethyl cyanoacetate) resulted in the desired quinolones and benzo[d][1,3]oxazines. This technique introduces a number of fundamental breakthroughs in organic synthesis, including metal-free catalysts, smart reaction conditions with column purification, and a wide functional scope. Furthermore, the structure of the newly synthesized chemical series was investigated and validated using spectroscopic techniques. The synthesized series were evaluated for antibacterial (against gram-positive and gram-negative bacterial strains) and antifungal activity. The quinolone and benzo[d][1,3]oxazine candidates had remarkable antibacterial action. Furthermore, molecular docking investigations corroborated the biological studies using the Molecular Operating Environment and Petro Osiris Molinspiration (POM) experiments, which confirmed the activity of compounds 8 , 15 , and 17 . Our studies on the cytotoxic activity of various chemicals have demonstrated that these compounds exhibit minimal toxicity. Specifically, when comparing the cytotoxic effects on human lung fibroblast (WI38) cells to those of Doxorubicin , a well-known chemotherapy agent, compounds 8 , 15 , and 17 showed weak cytotoxic effects on the normal WI38 cells. This indicates that these compounds may possess some level of selectivity and reduced toxicity towards normal cells, suggesting potential for further exploration as antibacterial agents with a safer profile for normal cells.

The coupling intensity modulator based on a triple-microring structure was proposed and numerically investigated for a high speed and a low bit error ratio (BER) operation. The modulator consists of a dual-microring optical cavity and a gate-microring energy feedback path. The optical cavity ensures a high energy storing efficiency, and the feedback path enables modulation with little intracavity energy decay. The bandwidth of 103 GHz and modulation depth of 6.2 dB at 2.0 Vpp were theoretically verified by the analysis of the sinusoidal modulation performance. Pulse modulation resulted in a data rate of 160 Gbps, an extinction ratio of 16.84 dB, and a BER of 1 × 10 −8 . The proposed modulator is applicable for compact, high-speed, and low-energy photonic integration.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.An amendment to this paper has been published and can be accessed via a link at the top of the paper.

An electro-optic (EO) modulator using a TiO 2 slot hybrid waveguide has been designed and fabricated. Optical mode calculations revealed that the mode was primarily confined within the slots when using a double-slot configuration, thus achieving a high EO activity experimentally. The TiO 2 slots also acted as an important barrier to induce an enhanced DC field during the poling of the EO polymer and the driving of the EO modulator. The hybrid phase modulator exhibited a driving voltage ( V π ) of 1.6 V at 1550 nm, which can be further reduced to 0.8 V in a 1 cm-long push-pull Mach–Zehnder interferometer (MZI) structure. The modulator demonstrated a low propagation loss of 5 dB/cm and a relatively high end-fire coupling efficiency.

To reduce the ever-increasing energy consumption in datacenters, one of the effective approaches is to increase the ambient temperature, thus lowering the energy consumed in the cooling systems. However, this entails more stringent requirements for the reliability and durability of the optoelectronic components. Herein, we fabricate and demonstrate silicon-polymer hybrid modulators which support ultra-fast single-lane data rates up to 200 gigabits per second, and meanwhile feature excellent reliability with an exceptional signal fidelity retained at extremely-high ambient temperatures up to 110 °C and even after long-term exposure to high temperatures. This is achieved by taking advantage of the high electro-optic (EO) activities (in-device n 3 r 33  = 1021 pm V −1 ), low dielectric constant, low propagation loss ( α , 0.22 dB mm −1 ), and ultra-high glass transition temperature ( T g , 172 °C) of the developed side-chain EO polymers. The presented modulator simultaneously fulfils the requirements of bandwidth, EO efficiency, and thermal stability for EO modulators. It could provide ultra-fast and reliable interconnects for energy-hungry and harsh-environment applications such as datacentres, 5G/B5G, autonomous driving, and aviation systems, effectively addressing the energy consumption issue for the next-generation optical communication. Information and communication datacentres require a large amount of energy for their cooling systems, which could be decreased by working at higher temperatures. Here, the authors introduce a silicon-polymer hybrid modulator that maintains high data rates for long periods at high temperatures that could be used under such conditions, to reduce energy consumption.

We propose a high efficiency apodized grating coupler with a bottom reflector for silicon nitride photonic integrated circuits. The reflector consists of a stack of alternate silicon nitride and silicon dioxide quarter-wave films. The design, fabrication and optical characterization of the couplers has been presented. The measured fiber to detector insertion loss was −3.5 dB which corresponds to a peak coupling efficiency of −1.75 dB. A 3 dB wavelength bandwidth of 76.34 nm was demonstrated for the grating coupler with a 20-layer reflector. The fabrication process is CMOS-compatible and requires only a single etching step.

We have studied the ring-opening metathesis polymerization of N -cyclohexyl- exo -norbornene-5,6-dicarboximide using the following 4 initiators: Grubbs 1, Grubbs 2, Hoveyda–Grubbs 1 ( HG1 ) and Hoveyda–Grubbs 2 ( HG2 ). Only the Grubbs 1 initiator was able to precisely control the polymer molecular weight. Polymerizations initiated by the HG1 , Grubbs 2 and HG2 initiators could not be controlled well. Both the Grubbs 1 and HG1 yielded polymers with a high trans % (85–98%), whereas Grubbs 2 and HG2 yielded polymers with a lower trans % (50–52%). The level of molecular weight control for the four initiators decreased in the order Grubbs 1> HG1 > HG2 >Grubbs 2. We also demonstrated that, in the case of polymers produced using Grubbs 1, the refractive indices (RIs) of the polymers decreased in a linear and controllable fashion from 1.539 to 1.534 at 633 nm, as the molecular weight was increased from 6700 to 26 400. This change represented a decrease in the RI of 0.005. Poly(NDI)s are a versatile class of polymers, which have been recently utilized as cell adhesion materials, membranes, insulating materials and in various optics applications. A well-controlled and clean polymerization profile is essential for successful manipulation of important physical properties such as glass transition temperature, decomposition temperature, refractive index, trans – cis content and molecular weight. We have investigated the ROMP of N -cyclohexyl- exo -norbornene-5,6-dicarboximide using four common initiators, Grubbs 1, Grubbs 2, Hoveyda–Grubbs 1 and Hoveyda–Grubbs 2. Only Grubbs 1 was found to be able to control the polymerization successfully, leading to a fine control over the molecular weight and associated physical properties.

This study not only explores the fabrication of rare zeolites from waste pumice and examines the impact of aging on their porosity and adsorbate uptake but also provides practical insights for waste management and agricultural applications. The use of organic templates was avoided in the synthesis due to their high cost and pollution associated with their calcination. Potassium-exchanged gonnardite (K-Gon) and perlialite were hydrothermally synthesized using KOH. Interestingly, we found that increasing the magnetic stirring duration during synthesis had a significant impact on the products’ surface area and pore volume, leading to an increase from 39 m²/g to 182 m²/g and from 0.11 cm³/g to 0.30 cm³/g, respectively. This improvement resulted in an increased adsorbate uptake at higher pressures. At shorter stirring times, potassium-exchanged gonnardite zeolite with tetragonal symmetry was the most prevalent phase, which differs from the orthorhombic symmetry of Na-rich gonnardites. Additionally, we observed that the product content of perlialite (hexagonal symmetry) increased with longer stirring durations while K + ions decreased. This suggests that increased stirring time can increase the disorderliness of extra framework particles, as seen in perlialite, as opposed to K-Gon. Longer stirring time produces other zeolites with slightly less K but improved textural properties, which can potentially accommodate more water. It is also useful for agricultural purposes, such as keeping soils moist and decontaminated, and as adsorbents for greenhouses’ air conditioning.

An effective synthetic approach of the Acetophenone Azo Anthrone Dye (4AAP-ANT) was achieved by modifying the dye through its incorporation into the cavity of β-cyclodextrin (β-CD), forming a 4AAP-ANT/β-CD inclusion complex. The structural features of the dye and its inclusion complex were characterized using Fourier-transform infrared (FT-IR) spectroscopy and X-ray diffraction (XRD) analysis. Additionally, thermal gravimetric analysis (TGA) was employed to evaluate the thermal stability of the synthesized materials. Thin films of 4AAP-ANT and its inclusion complex were prepared via spin coating, and their nanostructural properties were confirmed by XRD patterns and scanning electron microscopy (SEM). Optical properties such as the band gap, optical constants, dispersion, dielectric characteristics, and optical conductivity  were examined over the 200–2500 nm wavelength range based on absorbance, transmittance, and reflectance measurements under normal incidence light. Nonlinear optical properties were also assessed. The electrical conductivity of both 4AAP-ANT and its β-CD complex increased with temperature, indicating typical semiconductor behavior. These results suggest that the 4AAP-ANT/β-CD complex has significant potential as an organic semiconductor, with promising applications in organic optoelectronics such as organic light-emitting diodes (OLEDs) and organic solar cells (OSCs). Graphical Abstract

Poly(p-phenylene vinylene) PPV derivatives represent a pivotal class of π-conjugated materials with promising applications in organic electronic devices such as OLEDs, OFETs, and OPVs. Despite their significance, understanding the structure–property relationships in PPV derivatives remains challenging, particularly for oligomers. In this study, we synthesized PPV derivative oligomers via ROMP. The oligomers exhibited molecular weights of 3.46 kDa and 6.16 kDa, demonstrating well-controlled polymerization. The incorporation of alkyl side chains onto the oligomer backbone enhanced solubility and refined optical properties. UV–Vis analysis determined the optical band gaps (Eg op ) of the synthesized oligomers to range from 2.14 to 2.47 eV. Furthermore, TGA revealed two-step decomposition processes with onset decomposition temperatures (Td, onset) of 221.8°C and 218.5°C, and thermal decomposition maximum temperatures (Td, max) at 356.8°C and 324.0°C for Oligo-DO-PPV and Oligo-TO-PPV, respectively. These findings underscore the potential of ROMP as a versatile approach for tailoring PPV oligomers and provide critical insights into their structure–property relationships. This work advances our understanding of PPV oligomers, paving the way for future applications in optoelectronic devices. Graphical abstract