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The effect of nanoplasmonic (Ag) on the performance of DSSCs has been studied in doped and undoped ZnO (DZ and UZ) NPs, which were prepared by the urea-assisted combustion route. Different techniques were conducted to characterize DZ and UZ NPs. XRD patterns were indexed to the hexagonal wurtzite structure of ZnO NPs (ICSD-52362). The values of average crystalline size of UZ and DZ (1.0 mol% Ag) NPs were 20.45 and 22.30 nm, respectively. HR-TEM micrograph revealed good crystallization with an intermediate or poor agglomeration with distribution of semispherical morphologies of ZnO NPs. The energy bandgap of UZ and DZ NPs was changed from 3.21 to 3.31 eV. The deconvolution of the PL spectra recognized eight peaks into near ultraviolet (NUV) and visible regions. The PL emission of visible region overshadowed NUV transition. The photovoltaic cell with the doped photoanode DZ:1.0 mol% Ag exhibited the best performance parameters: Voc = 0.46 V, Jsc = 7.81 mA.cm−2, Pm = 1.91, FF = 51%, and η = 1.91%. A double exponential function was used as a powerful fitting function for the TOCVD data. The results revealed that τn in the UZ NPs photoanode was longer than that in the DZ:1.0 mol% Ag NPs photoanode.

Visible Light Communication (VLC) based light emitting diodes (LEDs) has pay great interest due to its high data rate and efficiency. In this paper, we aim to increase the efficiency by increasing the rate for a visible light communication and to minimise the BER for MIMO system deployed with beamforming. For increasing the data rate, GaN based LED is used because it has smaller carrier lifetime and lower junction capacitance. On-off keying (OOK) and Pulse-amplitude modulation (PAM) are taken into use for high speed communication. The interference may occur by any mobile obstacles could affect transmitted data and thus increases the BER. To improve the BER performance, we implemented optical beamforming technique to decrease the total interference and to increase the signal-to-noise ratio (SNR). Simulation results depicts the bit error rate (BER) performance with modulation scheme and without modulation scheme and illustrate the received power at the detector.

Sodium zinc borate glasses doped with dysprosium and modified with different concentrations of barium oxide (0e50 mol %) were fabricated using the melting quenching technique. The structural properties of the prepared glass systems were characterized using XRD and FTIR methods. The absorption spectra of the prepared glasses were measured to determine their energy gap and their related optical properties. The density of the glasses and other physical parameters were also reported. Additionally, with the help of Photon Shielding and Dosimetry (PSD) software, we investigated the radiation shielding parameters of the prepared glass systems at different energy values. It was found that an increase in the density of the glasses by increasing the concentration of BaO significantly improved the gamma ray shielding ability of the samples. For practical results, a compatible irradiation set up was designed to check the shielding capability of the obtained glasses using a gamma ray source at 662 keV. The experimentally obtained results strongly agreed with the data obtained by PDS software at the same energy. These results demonstrated that the investigated glass system is a good candidate for several radiation shielding applications when comparing it with other commercial shielding glasses and concretes. Sodium zinc borate glasses doped with dysprosium and modified with different concentrations of barium oxide (0e50 mol %) were fabricated using the melting quenching technique. The structural properties of the prepared glass systems were characterized using XRD and FTIR methods. The absorption spectra of the prepared glasses were measured to determine their energy gap and their related optical properties. The density of the glasses and other physical parameters were also reported. Additionally, with the help of Photon Shielding and Dosimetry (PSD) software, we investigated the radiation shielding parameters of the prepared glass systems at different energy values. It was found that an increase in the density of the glasses by increasing the concentration of BaO significantly improved the gamma ray shielding ability of the samples. For practical results, a compatible irradiation set up was designed to check the shielding capability of the obtained glasses using a gamma ray source at 662 keV. The experimentally obtained results strongly agreed with the data obtained by PDS software at the same energy. These results demonstrated that the investigated glass system is a good candidate for several radiation shielding applications when comparing it with other commercial shielding glasses and concretes.

In this work, easy and simple structured perovskite solar cells (PSCs) are designed and characterized. Our effort was to reduce the cost of the fabrication of such PSC devices, first by using an inexpensive starting precursor (aqueous methylamine solution) for the perovskite materials and second by design in a PSC structure free of the expensive hole transport layer (HTL). The CH3NH3PbI3 perovskite sols were deposited onto a conductive FTO glass using the spin coating technique followed by heating at 100 °C for 10 min. The structure of the films was characterized by X-ray diffraction (XRD) and their optical properties by UV–VIS spectrophotometry and photoluminescence (PL). The obtained phase confirmed the formation of a tetragonal perovskite structure. Two different solvents have been used, dimethylformamide (DMF) and dimethyl sulfoxide (DMSO). The effect of the type and the concentration of the used solvent DMF and DMSO on the performance of the solar cells have been investigated. It was found that a 40% concentration of the perovskite material resulted in the optimum film thickness that gives the best photoelectric performance. The DMF-based PSC assembled solar cell exhibited the best performance with an open circuit voltage of 750 mV, a photocurrent density of 12.5 mA/cm2, and an overall photon to electric conversion efficiency of 5.7%; all these results are higher than those of cells made with DMSO. This work was supported financially partially by the PHC Al Maqdisi Grant No. 37038WF and the Palestinian German Joint Research Project PALGER2015-34-012. The authors would like to thank Mr. Ahmad Ashour for his assistance in UV–VIS measurements. In this work, easy and simple structured perovskite solar cells (PSCs) are designed and characterized. Our effort was to reduce the cost of the fabrication of such PSC devices, first by using an inexpensive starting precursor (aqueous methylamine solution) for the perovskite materials and second by design in a PSC structure free of the expensive hole transport layer (HTL). The CH3NH3PbI3 perovskite sols were deposited onto a conductive FTO glass using the spin coating technique followed by heating at 100 °C for 10 min. The structure of the films was characterized by X-ray diffraction (XRD) and their optical properties by UV–VIS spectrophotometry and photoluminescence (PL). The obtained phase confirmed the formation of a tetragonal perovskite structure. Two different solvents have been used, dimethylformamide (DMF) and dimethyl sulfoxide (DMSO). The effect of the type and the concentration of the used solvent DMF and DMSO on the performance of the solar cells have been investigated. It was found that a 40% concentration of the perovskite material resulted in the optimum film thickness that gives the best photoelectric performance. The DMF-based PSC assembled solar cell exhibited the best performance with an open circuit voltage of 750 mV, a photocurrent density of 12.5 mA/cm2, and an overall photon to electric conversion efficiency of 5.7%; all these results are higher than those of cells made with DMSO.

It is very important to study the structural properties of the material to understand the physical properties. According to suggested cations distribution of Ni–Al ferrite as the formula $$({\text{Fe}}_{1 - t}^{3 + } {\text{Al}}_{t}^{3 + } )\left\{ {{\text{Ni}}^{2 + } {\text{Al}}_{x - t}^{3 + } {\text{Fe}}_{1 - x + t}^{3 + } } \right\}{\text{O}}_{4}^{2 - }$$ , with ( $$0.0 \le x \le 0.5$$ ) and ( $$0.0 \le t \le 0.1$$ ), the structural parameters were studied. The cations radii of tetrahedral ( $$R_{{\text{T}}}$$ ) did not change, but octahedral ( $$R_{O}$$ ) sites decreased with increasing Al3+ ions. Lattice constants ( $$a_{{{\text{th}}}}$$ ) decreased with increasing Al content. The values of $$u^{{\overline{4}3m}}$$ changed over the ranged 0.3818538155, whereas the values of $$u^{{\overline{3}m}}$$ varied from 0.25685 to 0.25655. With increasing Al content, M–M lengths decreased, in addition, the bond lengths q, r, and s decreased except p. In addition, with increasing Al3+ ions, $$\theta_{1}$$ , $$\theta_{2}$$ , and $$\theta_{5}$$ decreased but $$\theta_{3}$$ and $$\theta_{4}$$ increased. $$d_{{{\text{TE}}}}$$ and $$d_{{{\text{TL}}}}$$ were constant, whereas $$d_{{{\text{OEu}}}}$$ , $$d_{{{\text{OL}}}} ,$$ and $$d_{{{\text{OE}}}}$$ decreased with increasing Al3+ ions. $$L_{{{\text{T{-}T}}}}$$ , $$L_{{{\text{O{-}O}}}} ,$$ and $$L_{{{\text{T{-}O}}}}$$ reflected the same behavior as that of $$a_{{{\text{th}}}}$$ , where they decreased with increasing Al3+ ions concentration. As a result, the incorporation of non-magnetic Al3+ ions into the given ferrite system reduces the strength of the magnetic interactions, which relates to the changing on structural parameters.

A range of diazonium salts and their corresponding triazenes have been prepared in order to directly compare their relative thermal stabilities (via initial decomposition temperature) from differential scanning calorimetry (DSC) data. A structure–stability relationship has been explored to investigate trends in stability, depending on the aromatic substituent and the structure of the secondary amine component of the diazonium salts and triazenes. All of the triazenes investigated show significantly greater stability (many are stable above 200 °C) compared with the corresponding diazonium salts, which show varying stabilities.

Lanthanum gadolinium oxyorthosilicate or La2-xGdxSiO5 (x ¼ 0, 0.5, 1.0, 1.5 and 2.0) nanophosphors doped with dysprosium (Dy3þ) were prepared by urea- and ammonium nitrate-assisted solution combustion method. The X-ray diffraction (XRD) patterns confirmed that the phosphors crystallized in a mixed phase of La2SiO5 and La(OH)3 and a pure monoclinic phase of Gd2SiO5 or the admixtures of the three phases depending on the ratio of La:Gd in the host lattice. The estimated crystallite sizes were found to vary from 10 to 21 nm. The field emission scanning electron microscopy (FE-SEM) images showed that the particles were agglomerated together and they had no definite sizes. The chemical composition analyses and the electronic states were analyzed using the energy-dispersive X-ray spectroscopy (EDS) and X-ray photoelectron spectroscopy (XPS) respectively. The Fourier transform infrared spectroscopy (FTIR) data supplemented both the XRD and EDS data by confirming that the stretching mode frequencies were all related to La2SiO5 and Gd2SiO5, except a few absorption peaks ascribed to atmospheric moisture and hydrocarbons. The band gaps measured from the ultraviolet visible spectroscopy (UVeVis) data were shown to vary with the molar ratio of La to Gd. The photoluminescence spectra showed two characteristic emissions of Dy3þ at 485 nm (blue) and 573 nm (yellow) and an additional broad emission (in the blue region) with a maximum at ~415 nm. The International Commission on Illumination (CIE) chromaticity coordinates calculated from the fluorescence emission showed colours which were tuned from blue to white and yellow when the molar ratio of La to Gd in the La2-xGdxSiO5:Dy3þ lattice was varied. Depending on the excitation wavelength, energy transfer was observed from Dy3þ substituted in Gd3þ lattice sites to Dy3þ substituted in La3þ lattice sites. The internal photoluminescence quantum yield of the phosphors was measured using an integrating sphere method. Lanthanum gadolinium oxyorthosilicate or La2-xGdxSiO5 (x ¼ 0, 0.5, 1.0, 1.5 and 2.0) nanophosphors doped with dysprosium (Dy3þ) were prepared by urea- and ammonium nitrate-assisted solution combustion method. The X-ray diffraction (XRD) patterns confirmed that the phosphors crystallized in a mixed phase of La2SiO5 and La(OH)3 and a pure monoclinic phase of Gd2SiO5 or the admixtures of the three phases depending on the ratio of La:Gd in the host lattice. The estimated crystallite sizes were found to vary from 10 to 21 nm. The field emission scanning electron microscopy (FE-SEM) images showed that the particles were agglomerated together and they had no definite sizes. The chemical composition analyses and the electronic states were analyzed using the energy-dispersive X-ray spectroscopy (EDS) and X-ray photoelectron spectroscopy (XPS) respectively. The Fourier transform infrared spectroscopy (FTIR) data supplemented both the XRD and EDS data by confirming that the stretching mode frequencies were all related to La2SiO5 and Gd2SiO5, except a few absorption peaks ascribed to atmospheric moisture and hydrocarbons. The band gaps measured from the ultraviolet visible spectroscopy (UVeVis) data were shown to vary with the molar ratio of La to Gd. The photoluminescence spectra showed two characteristic emissions of Dy3þ at 485 nm (blue) and 573 nm (yellow) and an additional broad emission (in the blue region) with a maximum at ~415 nm. The International Commission on Illumination (CIE) chromaticity coordinates calculated from the fluorescence emission showed colours which were tuned from blue to white and yellow when the molar ratio of La to Gd in the La2-xGdxSiO5:Dy3þ lattice was varied. Depending on the excitation wavelength, energy transfer was observed from Dy3þ substituted in Gd3þ lattice sites to Dy3þ substituted in La3þ lattice sites. The internal photoluminescence quantum yield of the phosphors was measured using an integrating sphere method.

ZnO nanoparticles (ZnONPs) were synthesized usinghydrothermal and sol-gel techniquesusing zinc acetate dihydrate (Zn (CH3COO)2.2H2O) as a row material and methanol as a solvent. The structural properties of ZnO NPs were studied using EDX, XRD, TEM, and the optical properties were characterized using UV-VIS and PL spectroscopies. The synthesized ZnO NPs showedhigh purity and revealed a wurtzite (hexagonal) crystal structure with particle size (D) ranged from25 nm to 28 nm. The UV-VIS absorption spectra of ZnO NPs samples and sensitizing dyes were performed.The obtained ZnO NPs exhibited the direct optical bandgap 3.15 eV. Dye-sensitized solar cells (DSSCs) were fabricated using synthesized ZnO NPsas a semiconducting layer, whichwas dyedwith different low cost dyes such as Eosin B (EB), Eosin Y (EY) and Rhodamine B (RB) that was used to sensitize the photoanode (ZnO NPs).The experimental results showed a significant efficiency for the fabricated DSSCs of synthesized ZnO NPs via sol gel technique comparing to hydrothermal technique. The EY dye exhibited the bestperformanceamong others, where a conversion efficiency showed a noteworthy improvement from 0.12 to 1.08 %. ZnO nanoparticles (ZnONPs) were synthesized usinghydrothermal and sol-gel techniquesusing zinc acetate dihydrate (Zn (CH3COO)2.2H2O) as a row material and methanol as a solvent. The structural properties of ZnO NPs were studied using EDX, XRD, TEM, and the optical properties were characterized using UV-VIS and PL spectroscopies. The synthesized ZnO NPs showedhigh purity and revealed a wurtzite (hexagonal) crystal structure with particle size (D) ranged from25 nm to 28 nm. The UV-VIS absorption spectra of ZnO NPs samples and sensitizing dyes were performed.The obtained ZnO NPs exhibited the direct optical bandgap 3.15 eV. Dye-sensitized solar cells (DSSCs) were fabricated using synthesized ZnO NPsas a semiconducting layer, whichwas dyedwith different low cost dyes such as Eosin B (EB), Eosin Y (EY) and Rhodamine B (RB) that was used to sensitize the photoanode (ZnO NPs).The experimental results showed a significant efficiency for the fabricated DSSCs of synthesized ZnO NPs via sol gel technique comparing to hydrothermal technique. The EY dye exhibited the bestperformanceamong others, where a conversion efficiency showed a noteworthy improvement from 0.12 to 1.08 %.

Europium (Eu3+) and bismuth (Bi3+) co‐activated LiBaBO3 powder phosphors were synthesized by a solid‐state reaction and the structure, particle morphology, optical and photoluminescent properties were investigated. X‐Ray diffraction patterns of the LiBaBO3 phosphors crystallized in a pure monoclinic phase, i.e. there were no secondary phases due to either incidental impurities or undecomposed starting materials. Scanning electron microscopy images showed that the powders were made up of fluffy needle‐like particles that were randomly aligned. The bandgap of the LiBaBO3 host was estimated to be 3.33 eV from the UV/vis absorption data. Blue emission was observed from the LiBaBO3 host, which is ascribed to self‐activation of the host matrix. In addition, greenish‐blue (493 nm) and red (613 nm) emissions were observed from europium‐doped samples and were attributed to the emissions of Eu2+ and Eu3+, respectively. Furthermore, after codoping with Bi3+, the emission intensity of Eu3+ located at 613 nm was significantly enhanced. From the Commission Internationale de I′Eclairage (CIE) color coordinates, white emission was observed from LiBa1–xBO3:xEu3+ (x = 0.020 and 0.025) phosphor powders with color coordinates of x = 0.368, y = 0.378 and x = 0.376, y = 0.366, respectively. National Research Foundation, Grant/Award Number: CPR20110724000021870; Council for Scientific and Industrial Research, Grant/ Award Number: NLC‐LREGM00‐CON‐001 Europium (Eu3+) and bismuth (Bi3+) co‐activated LiBaBO3 powder phosphors were synthesized by a solid‐state reaction and the structure, particle morphology, optical and photoluminescent properties were investigated. X‐Ray diffraction patterns of the LiBaBO3 phosphors crystallized in a pure monoclinic phase, i.e. there were no secondary phases due to either incidental impurities or undecomposed starting materials. Scanning electron microscopy images showed that the powders were made up of fluffy needle‐like particles that were randomly aligned. The bandgap of the LiBaBO3 host was estimated to be 3.33 eV from the UV/vis absorption data. Blue emission was observed from the LiBaBO3 host, which is ascribed to self‐activation of the host matrix. In addition, greenish‐blue (493 nm) and red (613 nm) emissions were observed from europium‐doped samples and were attributed to the emissions of Eu2+ and Eu3+, respectively. Furthermore, after codoping with Bi3+, the emission intensity of Eu3+ located at 613 nm was significantly enhanced. From the Commission Internationale de I′Eclairage (CIE) color coordinates, white emission was observed from LiBa1–xBO3:xEu3+ (x = 0.020 and 0.025) phosphor powders with color coordinates of x = 0.368, y = 0.378 and x = 0.376, y = 0.366, respectively.

The main goal of this work is to find a simple mathematical model to calculate parasitic components for the materials in AC circuit. There are different methods such as Delay-Time, Lissajous, Product and Curve-fitting that can be performed to study the parasitic properties. Among them, the Delay-Time method can be achieved to find the phase shift (φ) between any two different sine waves using an oscilloscope. The φ was exercised to resolve the parallel model for the examined sample in AC circuit. The phasor diagram of the parallel sample model in AC circuit was plotted. All the fundamental and derived quantities of the AC circuit can be calculated, such as the immittances, conductivity and dielectric parameters. The presented method is considered as a simple method comparing to others. Therefore, it can be replaced the others as well as it can be used from the scientists and engineers. The main goal of this work is to find a simple mathematical model to calculate parasitic components for the materials in AC circuit. There are different methods such as Delay-Time, Lissajous, Product and Curve-fitting that can be performed to study the parasitic properties. Among them, the Delay-Time method can be achieved to find the phase shift (φ) between any two different sine waves using an oscilloscope. The φ was exercised to resolve the parallel model for the examined sample in AC circuit. The phasor diagram of the parallel sample model in AC circuit was plotted. All the fundamental and derived quantities of the AC circuit can be calculated, such as the immittances, conductivity and dielectric parameters. The presented method is considered as a simple method comparing to others. Therefore, it can be replaced the others as well as it can be used from the scientists and engineers.

The influence of Dy3+ concentration and annealing on the structure and photoluminescence properties of lanthanum gadolinium oxyorthosilicate (LaGdSiO5) was studied in detail. The X-ray diffraction patterns of the samples annealed at 1000 °C for 1 h showed new peaks which were not observed in the asprepared samples. Also some peaks which were in the as-prepared samples were not observed in the annealed samples. These observations suggest that there was phase transformation caused by annealing. The chemical composition and states of the as-prepared and annealed samples were analysed using time of flight secondary ion mass spectroscopy and X-ray photoelectron spectroscopy respectively. The excitation spectra of the as-prepared samples when monitoring the emission at 573 nm using a monochromatic xenon lamp showed two peaks located at 227 and 241 nm whose intensities varied with the Dy3+ concentration. However, after annealing, the intensity of the 241 nm excitation peak decreased drastically. When the emissionwas monitored at 227 and 241 nm, two prominent emission peaks located at 485 and 573 nm which were ascribed respectively to the 4F9/2-6H15/2 and 4F9/2-6H13/2 transitions of Dy3+ were observed. When the samples were excited using a 325 nm He–Cd laser, an additional broad emission peak was observed around 400 to 460 nm which was ascribed to self-trapped excitons (STE) in SiO2. This broad peak decreased after annealing due to reduction in the defects concentration and the subsequent change in the CIE color coordinates. The mechanism of the STE emission is discussed. of lanthanum gadolinium oxyorthosilicate (LaGdSiO5) was studied in detail. The X-ray diffraction patterns of the samples annealed at 1000 °C for 1 h showed new peaks which were not observed in the asprepared samples. Also some peaks which were in the as-prepared samples were not observed in the annealed samples. These observations suggest that there was phase transformation caused by annealing. The chemical composition and states of the as-prepared and annealed samples were analysed using time of flight secondary ion mass spectroscopy and X-ray photoelectron spectroscopy respectively. The excitation spectra of the as-prepared samples when monitoring the emission at 573 nm using a monochromatic xenon lamp showed two peaks located at 227 and 241 nm whose intensities varied with the Dy3+ concentration. However, after annealing, the intensity of the 241 nm excitation peak decreased drastically. When the emissionwas monitored at 227 and 241 nm, two prominent emission peaks located at 485 and 573 nm which were ascribed respectively to the 4F9/2-6H15/2 and 4F9/2-6H13/2 transitions of Dy3+ were observed. When the samples were excited using a 325 nm He–Cd laser, an additional broad emission peak was observed around 400 to 460 nm which was ascribed to self-trapped excitons (STE) in SiO2. This broad peak decreased after annealing due to reduction in the defects concentration and the subsequent change in the CIE color coordinates. The mechanism of the STE emission is discussed.

Although current chemotherapeutic agents are active at the beginning of therapy, the most common risk is the development of resistance during later stages in almost all cancer types including breast cancer. Hence, investigation of novel drugs is still a priority goal for cancer treatment. The objective of the present study is to investigate the anticancer effect of a derivative of stilbene, deoxyrhapontigenin (DR) isolated from Rheum undulatum L. root extracts against the chemoresistant MCF-7/adr and its parental MCF-7 human breast cancer cells. The morphological images indicate that DR induces an extensive cytoplasmic vacuolation in breast cancer cells. Mechanistic investigations revealed that DR treatment causes endoplasmic reticulum (ER) dilation and upregulated the expression of ER stress markers GRP78, IRE1α, eIF2α, CHOP, JNK, and p38. Subsequently, we also identified that DR increases the levels of apoptotic fragment of PARP (89 kDa) in breast cancer cells. Blocking the expression of one of the components of the ER stress–mediated apoptosis pathway, CHOP using siRNA significantly decreased DR-induced apoptotic cleavage of PARP. In summary, the present study suggests that the induction of ER stress–mediated apoptosis by DR may account for its cytotoxic effects in human breast cancer cells.