The Université Constantine 1, formerly the University of Mentouri, is a university located in Constantine, Algeria. Designed by Brazilian architect Oscar Niemeyer, the university was built from 1969 to 1972.
Flexible and multifunctional ultraviolet–visible (UV–Vis) photodetectors are highly desirable for next-generation wearable healthcare devices. In this work, we report novel PVC/n-ZnO/p-MxOy (M = Ni, Cu, Ag) heterojunction composite films designed as broadband photodetectors with additional antibacterial functionality. The ZnO/MxOy composites were synthesized via a hydrothermal method and embedded within a polyvinyl chloride (PVC) matrix to yield flexible films. Structural, morphological, and optical characterizations (XRD, FTIR, SEM, EDX, UV–Vis) confirmed high-purity heterojunction formation, good crystallinity, and homogeneous morphology, with broad absorption (200–800 nm) and tunable bandgaps (1.4–3.24 eV) due to the presence of secondary metal oxides (NiO, CuO, Cu2O and Ag2O) alongside ZnO. Antibacterial activity was evaluated using the agar diffusion method, revealing strong inhibition against Gram-positive bacteria (Bacillus and Staphylococcus aureus). Photodetection performance was studied via current–voltage (I–V) measurements under dark, UV, and visible light. All devices exhibited rectifying behavior, confirming efficient n–p heterojunction formation. Among the tested devices, the PVC/ZnO/Ag2O heterojunction exhibited superior performance, achieving a responsivity of 12.7 µA/W and a detectivity of 3.08 × 10⁸ Jones under UV illumination at 5 V bias. I–t measurement revealed stable and repeatable switching, with rise and decay times of 85 s and 130 s, respectively. The device also demonstrated outstanding long-term reliability, maintaining 97
The aim of the current study is assessing the in vitro anti-inflammatory and antioxidant properties of Laurus nobilis methanolic extract (LNME) and to investigate their impacts on experimental oxidative stress in ulcerative colitis caused by acetic acid (AA). The in vitro antioxidant ability of LNME was evaluated using four tests (DPPH, ABTS, FRAP, and CUPRAC). The anti-inflammatory capacity was assessed using the protein denaturation technique, on the basis of total polyphenol measurement. In an in vivo study, 28 rats were equitably divided into four groups: (1) control group, (2) Laurel group: Rats receiving 250 mg/kg B.W of LNME, (3) AA group: Rats receiving 2 mL/kg B.W of AA (3 The current study suggests that LNME displays anti-inflammatory, and antioxidant potential and a cytoprotective impact supporting its uses to alleviate ulcerative and colonic oxidative stress.
This study investigates the enhancement of the thermal, structural, and optical properties of elastomeric polyolefin (POE)/phase change material (PCM(C25H52)) composite polymers through the incorporation of zinc oxide (ZnO) nanoparticles, targeting applications in thermal energy storage, photovoltaics, and encapsulation. Composites were prepared with varying ZnO doping levels (0%, 10%, and 30%) and characterized using differential scanning calorimetry, thermogravimetric analysis, X-ray diffraction, scanning electron microscopy, Fourier transform infrared spectroscopy, and photoluminescence spectroscopy. The results demonstrate that the addition of ZnO nanoparticles significantly improves thermal stability, energy storage capacity, and heat transfer efficiency. The 30% ZnO-doped composite exhibited the highest melting temperature (90.5 degrees C), no mass loss up to 180 degrees C, and the greatest thermal conductivity, making it a promising candidate for thermal energy storage and encapsulation. X-ray diffraction analysis confirmed the successful incorporation of ZnO nanoparticles and an increase in crystallinity with doping, while photoluminescence spectra revealed enhanced optical properties due to defect passivation. The POE/PCM(C25H52) matrix provides a stable environment that preserves the intrinsic properties of ZnO nanoparticles, enabling their effective integration into the composite. These findings highlight the potential of ZnO-doped POE/PCM(C25H52) composites for advanced applications in thermal energy storage, heat management, opto electronics, and encapsulation particularly in photovoltaic systems, where uniform dispersion of ZnO nanoparticles can enhance light absorption, charge transport, and device durability.
Securing and tracing medical audio data is crucial in telemedicine and digital archiving. This paper presents a blind and irreversible audio watermarking scheme designed to satisfy imperceptibility, robustness, and embedding capacity requirements for sensitive medical applications. The method integrates the Fractional Charlier Transform (FrCT) for adaptive time-frequency analysis, local entropy analysis with the Watson perceptual model for intelligent coefficient selection, and adaptive logarithmic quantization index modulation (LQIM) for embedding. It securely incorporates patient and acquisition metadata, ensuring confidentiality and integrity via cryptographic and error-correction techniques. Experiments demonstrate a payload of 67.3 bits per second, high audio transparency (SNR > 36 dB, PESQ > 4.0), and robustness against various signal processing attacks (average BER 4.5
Welding is a fundamental technique for joining materials in industrial applications and large-scale construction. Various methods are employed to ensure robust connections. Resistance spot welding is ideal for thin sheets due to its speed, low cost, short processing times, and easy integration into automation systems. Stainless steel is widely used in many food and beverage industries because of its durability and ability to withstand diverse conditions. However, despite the existence of modeling approaches, predictive models linking weld parameters to the simultaneous improvement of stiffness and tensile strength in different joint regions remain limited in published studies. Many studies treat the weld as a single homogeneous region or focus primarily on general indicators such as tensile strength or weld diameter. The spatial variation in properties between the weld region, the heat-affected region, and the base metal is often not modeled separately. This study examines the effect of welding current and welding time on the mechanical properties of weld beads. Scanning electron microscopy (SEM) was also used to characterize the weld microstructure. The combination of mechanical evaluation and microstructural analysis provides deeper insight into the relationship between welding parameters and weld quality. Among the conditions studied (6-8 kA, 60-120 ms), the optimal parameters (6 kA, 120 ms) produced the maximum hardness of 178.16 HV observed in the weld zone and a tensile strength of 12 kN. The experimental results demonstrated that welding parameters significantly influence weld bead quality, and the optimization study allowed us to identify the parameters that achieve the best possible mechanical properties and optimal operating conditions. The experimental results demonstrated that welding parameters significantly influence weld bead quality, and the optimization study using Response Surface Methodology (RSM) allowed us to identify the parameters that achieve the best possible mechanical properties and optimal operating conditions.
