Use Of Zinc Oxide Research Articles

The Use of Zinc Oxide (ZnO) Photocatalyst for Photodegradation of Car Wash Wastewater

The Use of Zinc Oxide (ZnO) Photocatalyst for Photodegradation of Car Wash Wastewater

Biodegradable PLA-ZnO nanocomposite biomaterials with antibacterial properties, tissue engineering viability, and enhanced biocompatibility

Polylactic acid (PLA) is a well-known biomaterial on account of its biocompatibility and biodegradability. Zinc oxide (ZnO) nanofillers may endow PLA with advantageous antibacterial and tissue regenerative properties, but may also compromise the biocompatibility of PLA. Several strategies have been developed to improve the biomedical practicality of such composites. The importance of surface properties on amplifying the therapeutic properties and safety of a material enables two potential strategies: (i) surface modification of ZnO nanoparticles, and (ii) surface engineering of the PLA/ZnO composites. Moreover, the controllable biodegradation of PLA allows a third possible strategy: (iii) biodegradation-controlled release of ZnO. The first part of this review introduces the controllable degradation of PLA and the mechanisms of therapeutic properties and cytotoxicity of ZnO. Following this, the paper highlights current research trends regarding the biomedical application of PLA-based ZnO nanocomposites. The final section of this review discusses the potential use of ZnO in tuning the degradation rate of PLA, and the possibility of manipulating the surface properties of ZnO nanoparticles and PLA/ZnO composites in order to optimize the therapeutic properties and safe usage of PLA/ZnO composites in the biomedical field.

Clinical, Radiographic and Microbiological Evaluation of Different Obturating Materials in Pulpectomy of Primary Molars

Purpose: to assess the use of Zinc oxide and Eugenol, Endoflas and Plant flavonoid (hesperidin) as obturating materials in pulpectomy of primary molars by using clinical, radiographical and microbiological evaluation. Material and Methods:(In vivo study) a number of 90 primary teeth indicated for pulpectomy were divided equally into three groups according to the root canal obturating material. Group I (30 teeth) (control group) obturated with Zinc oxide and Eugenol material. Group II (30 teeth) obturated with Endoflas material. Group III (30 teeth) obturated with hesperidin extract and Zinc oxide material. A periapical radiograph was taken for each treated molar immediately postoperative, after 3 and after 6months. Clinical and radiographic follow-up for success and failure was performed. The three obturating materials were evaluated against Enterococcus faecalis by using agar diffusion method. Results: after 6 months: Group II (Endoflas group) reported the highest success rate (100%), followed by Group I (ZnO/Eugenol group) (76.7%), with the least success value recorded in Group III (Hesperidin group) (60%). Conclusions: Endoflas material is a good alternative to ZnO/Eugenol in pulpectomy of primary molars.

On the In Vitro and In Vivo Hazard Assessment of a Novel Nanomaterial to Reduce the Use of Zinc Oxide in the Rubber Vulcanization Process.

Zinc oxide (ZnO) is the most efficient curing activator employed in the industrial rubber production. However, ZnO and Zn(II) ions are largely recognized as an environmental hazard being toxic to aquatic organisms, especially considering Zn(II) release during tire lifecycle. In this context, aiming at reducing the amount of microcrystalline ZnO, a novel activator was recently synthetized, constituted by ZnO nanoparticles (NPs) anchored to silica NPs (ZnO-NP@SiO2-NP). The objective of this work is to define the possible hazards deriving from the use of ZnO-NP@SiO2-NP compared to ZnO and SiO2 NPs traditionally used in the tire industry. The safety of the novel activators was assessed by in vitro testing, using human lung epithelial (A549) and immune (THP-1) cells, and by the in vivo model zebrafish (Danio rerio). The novel manufactured nanomaterial was characterized morphologically and structurally, and its effects evaluated in vitro by the measurement of the cell viability and the release of inflammatory mediators, while in vivo by the Fish Embryo Acute Toxicity (FET) test. Resulting data demonstrated that ZnO-NP@SiO2-NP, despite presenting some subtoxic events, exhibits the lack of acute effects both in vitro and in vivo, supporting the safe-by-design development of this novel material for the rubber industry.

Development of doped ZnO-based biomimicking and tumor-targeted nanotheranostics to improve pancreatic cancer treatment

Despite different nanomaterials were developed so far against cancer, their potential drawbacks are still scarcely considered. The off-target delivery of a therapeutic compound, as well as the non-specific uptake of these nanomaterials by healthy tissues or organs, and their potential immunogenicity are some of the major issues that still have to be faced prior to a successful clinical translation. This work aims to develop an innovative theranostic, biocompatible, and drug-loaded nanoconstruct based on Gadolinium-doped Zinc Oxide (ZnO-Gd) nanocrystals (NCs), focusing on one of the most lethal diseases, i.e., pancreatic cancer. The use of zinc oxide is motivated by the huge potential of this nanomaterial already demonstrated for in vitro and in vivo applications, while the Gadolinium doping confers magnetic properties useful for diagnostics. Furthermore, an innovative biomimetic shell is here used to coat the NCs: it is composed of a lipid bilayer made from extracellular vesicles (EVs) combined with other synthetic lipids and a peptide targeting the pancreatic tumor microenvironment. To complete the nanoconstruct therapeutic function, Gemcitabine, a first-line drug for pancreatic cancer treatment, was adsorbed on the ZnO-Gd NCs prior to the coating with the above-mentioned lipidic shell. The aim of this work is thus to strongly enhance the therapeutic capability of the final nanoconstruct, providing it with high biocompatibility, colloidal stability in biological media, efficient cargo loading and release properties, as well as active targeting for site-selective drug delivery. Furthermore, the magnetic properties of the ZnO-Gd NCs core can in future allow efficient in situ bioimaging capabilities based on Magnetic Resonance Imaging technique. The obtained nanoconstructs were tested on two different pancreatic cancer cell lines, i.e., BxPC-3 and the metastatic AsPC-1, proving high cell internalization levels, mediated by the targeting peptide exposed on the nanoconstruct. Cellular cytotoxicity assay performed on both cell lines dictated ~ 20% increased cell killing efficacy of Gemcitabine when delivered through the nanoconstruct rather than as a free drug. Taken together, our designed theranostic nanoconstruct can have a significant impact on the standard treatment of pancreatic cancer.

Effect of fermented rapeseed meal in the mixture for growing pigs on the gastrointestinal tract, antioxidant status, and immune response

The ban on the use of zinc oxide has increased interest in probiotics, prebiotics, synbiotics and organic acids, as well as fermented components in the diet of weaned piglets. This study assessed the effect of 8% fermented rapeseed meal in weaner diets on characteristics of the gastrointestinal tract, the small intestinal microbiota, and immune and antioxidant status. The effects were determined by measuring biochemical and haematological blood parameters, levels of class G, A and M immunoglobulins and IL-6, and the antioxidant potential of the plasma. After slaughter, the gastrointestinal tract was measured, the viscosity of the digesta was determined, and microbiological tests were performed. The results showed that the fermented component reduced the viscosity of the digesta and the length of segments of the gastrointestinal tract. It caused a statistically significant increase in lactic acid bacteria and a decrease in total bacteria. The haematological and biochemical analyses of the blood confirmed the biological activity of the fermented component. Pigs from group FR had significantly higher haemoglobin levels (p = 0.001), RBC count (p = 0.015), and haematocrit (Ht) value (p < 0.001) than the control animals. A diet including 8% rapeseed meal fermented using Bacillus subtilis strain 87Y benefits gastrointestinal function by stabilizing and improving the function of the bacterial microbiota, inhibiting growth of certain pathogens, and strengthening immunity.

Nanoarchitectonics of (110) directed polyethylene glycol stabilized cerium nanoparticles for UV filtering applications

The use of zinc oxide (ZnO) and titanium oxide (TiO2) nanoparticles in ultraviolet (UV) filters can cause serious health issues due to their genotoxicity and cytotoxicity effect. Recent research on cerium oxide (CeO2) nanoparticles has demonstrated their biocompatible nature, excellent antioxidant and ultraviolet–visible (UV–Vis) absorption properties. CeO2-based nanocomposite materials or nano-architectures can offer uniform absorptive properties, therapeutic skin effect and easy skin application. In this study, cerium oxide-polyethylene glycol (CeO2-PEG) nano-architecture was prepared by hydrothermal processing with the aim to improve stability, antioxidant properties, and enhance UV absorption for UV filtering applications. The morphology study of the developed nanocomposite revealed the formation of polymer bands with well-dispersed CeO2 nanoparticles. The nanocomposite structure has exhibited excellent UV absorption in the UV range 200–400 nm due to decrease in optical band gap in comparison to the naked CeO2 NPs. The evaluation of the photocatalytic activity (PCA) of the nanocomposite structure against P25 photocatalyst and ZnO nanoparticles showed no dye (crystal violet) degradation on UV irradiation. Hence, PCA assay verified the absence of ROS generation and increased stability of the nanostructure under UV irradiation. The investigation of antioxidant properties of the Ce-PEG nanocomposite by a dichlorofluorescein (DCF)-based assay revealed sufficient intracellular ROS scavenging in comparison to N-acetylcysteine (NAC) and H2O2 only assays. In vitro toxicity evaluation of Ce-PEG nanocomposite towards non-malignant human keratinocyte cell line (HaCaT) revealed a non-significant cell mortality ~ 10% of control at a dosage of 50 mg L−1. The nanocomposite structure also exhibited excellent UV protection for HaCaT cells under UV irradiation conditions compared to P25. Our findings suggest that the developed nanocomposite combined the antioxidant and UV absorption properties of CeO2 and skin emollient role of (PEG), and hence offered a novel biocompatible and multifunctional structure for sunscreens and therapeutic skin product.Graphical abstract

The Effects of Exposure Methods on the Toxicity of Zinc Oxide Nanoparticles

In recent years, with the widespread use of zinc oxide (ZnO) nanoparticles (NPs), more and more attentions are being given to its biological toxicity, the toxicity of ZnO NPs under different exposure methods is necessary to investigate. In this study, we prepared two ZnO dispersions with different particle sizes, namely small-size ZnO (S-ZnO) and Bigsize ZnO (B-ZnO), using polycarboxylic acid as dispersant. Mice were poisoned by intravenous injection and inhalation, respectively. The respiration coefficient, superoxide dismutase (SOD), Zn content in the organs of the mice were detected. It was discovered that ZnO NPs with smaller particle diameter can cause more serious toxicity in vivo after intravenous exposure and respiratory exposure. In addition, the mice showed symptoms of dyspnea after respiratory exposure and a massive number of fibroblasts were found in the alveolar structure of the lungs. In the intravenous injection group, the content of Zn in the liver and spleen of mice increased significantly, resulting in organ edema, and the organ coefficient of mice increased. Finally, the increase of GSH/GSSG indicated that cells were regulated under the antioxidant mechanism, which accelerated the removal of H2O2 from cells. In addition, the increase of GSH+GSSG content also indicated that ZnO NPs stimulated the creation of reactive oxygen species (ROS) in organs of experimental animals.

SpICP-MS assessment of ZnONPs and TiO2NPs in moisturisers after a tip sonication sample pre-treatment

The use of zinc oxide (ZnONPs) and titanium dioxide nanoparticles (TiO2NPs) in cosmetic formulations to obtain protection against the sun's UV radiation has become a common practice owing to their high photo-stability and the absence of allergic reactions of these nanomaterials. The manufacturing of cosmetics modified with nanoparticles has been regulated in Europe since 2009. Nevertheless, methodologies for sample pre-treatment and characterisation (quantification and size assessment) of nanoparticles from complex matrices are scarce and still in development.The proposed methodology was based on the tip sonication of moisturisers in an organic solvent [40 mL of acetone, 40% amplitude, 5 min and discontinuous mode with 59 s of relax after 59 s tip sonication] followed by spICP-MS, which provides information about concentration and size of the NPs. The whole methodology was repeatable (RSDs lower than 10% for size and concentration values of ZnONPs and TiO2NPs) and accurate (analytical recoveries of 102 ± 12% and 119 ± 3%for ZnONPs and TiO2NPs standards, respectively).The over-all procedure was applied to several commercial moisturisers with solar sun protection. spICP-MS results were compared with total content of analyte in the extracts and in the acid digested samples. Finally, transmission electron microscopy coupled to energy dispersive X-ray spectroscopy analysis of extracts from moisturising creams was carried out as comparative (qualitative) assessment.

Enzymatic approach in accelerating colloidal stability of concentrated natural rubber latex and its effect on rubber products

In this work, enzymatic treatment was thoroughly investigated as an environmentally benign method for accelerating the colloidal stability and maturation rate of concentrated natural rubber latex (CNRL). It was found that the treatment of CNRL with lipase, an enzyme that catalyze the hydrolysis of lipids and phospholipids, was much more effective in boosting the colloidal stability of CNRL than the use of commercial ammonium laurate soap without causing an over-stabilized problem at longer time. The investigation of lipase treatment in CNRL obtained from different production lots indicated that the lipid content in CNRL was the key parameter in determining maturation rate of lipase-treated latex: the latex lot with higher lipid content could be maturated faster. Moreover, lipase treatment could also reduce the use of ammonia by at least 50% (from 0.6 to 0.7 to less than 0.29 wt%) and could completely replace the use of zinc oxide and tetramethylthiuram disulfide (TMTD), a carcinogenic chemical commonly used in low-ammonia latex, without affecting its colloidal stability. For the effect on the downstream processes, it was found that lipase treatment did not cause any adverse effect to downstream product-forming process but could also lead to stronger cross-linking bonds and better rubber product quality.

Epoxy Composites Reinforced with ZnO from Waste Alkaline Batteries.

The zinc alkaline battery is one of the most popular sources of portable electrical energy, with more than 300,000 tons being consumed per year. Accordingly, it is critical to recycle its components. In this work, we propose the use of zinc oxide (ZnO) microparticles recovered from worn-out batteries as fillers of epoxy resins. These nanocomposites can be used as protective coatings or pigments and as structural composites with high thermal stability. The addition of ceramic nanofillers, such as ZnO or/and TiO2, could enhance the thermal and mechanical properties, and the hardness and hydrophobicity, of the epoxy resins, depending on several factors. Accordingly, different nanocomposites reinforced with recycled ZnO and commercial ZnO and TiO2 nanoparticles have been manufactured with different nanofiller contents. In addition to the different ceramic oxides, the morphology and size of fillers are different. Recycled ZnO are“desert roses” such as microparticles, commercial ZnO are rectangular parallelepipeds nanoparticles, and commercial TiO2 are smaller spherical nanoparticles. The addition of ceramic fillers produces a small increase of the glass transition temperature (<2%), together with an enhancement of the barrier effect of the epoxy resin, reducing the water diffusion coefficient (<21%), although the maximum water uptake remains constant. The nanocomposite water absorption is fully reversible by subsequent thermal treatment, recovering its initial thermomechanical behavior. The water angle contact (WCA) also increases (~12%) with the presence of ceramic particles, although the highest hydrophobicity (35%) is obtained when the epoxy resin reinforced with recycled flowerlike ZnO microparticles is etched with acid stearic and acetic acid, inducing the corrosion of the ZnO on the surface and therefore the increment of the surface roughness. The presence of desert rose ZnO particles enhances the de lotus effect.

Revealing a Zinc Oxide/Perovskite Luminescence Quenching Mechanism Targeting Low-Roll-off Light-Emitting Diodes.

Balanced charge injection is key to achieving perovskite light-emitting diodes (PeLEDs) with a low efficiency roll-off at a high brightness. The use of zinc oxide (ZnO) with a high electron mobility as the charge transport layers is desirable; however, photoluminescence (PL) quenching of a perovskite on ZnO always occurs. Here, a quasi-two-dimensional perovskite on ZnO is explored to uncover the PL quenching mechanism, mainly ascribed to the deprotonation of ammonium cations on the ZnO film in association with the decomposition of low-dimensional perovskite phases. Surprisingly, crystal plane-dependent PL quenching results indicate that the deprotonation rate strongly correlates with the crystal orientation of the ZnO surface. We developed a strategy for suppressing perovskite PL quenching by incorporating an atomic layer deposited Al2O3 onto the ZnO film. Consequently, an efficient inverted PeLED was achieved with a maximum external quantum efficiency of 17.7% and a less discernible efficiency roll-off at a high current density.

Toward Mechanically Robust Crosslinked Elastomers through Phase Transfer Agent Tuning the Solubility of Zn2+ in the Organic Phase.

Zinc oxide (ZnO), which is toxic to aquatic organisms, is widely used as an activator in the rubber industry. The reduction of ZnO content is one of the efficient ways to tackle ecological environment impacts induced by ZnO. However, the incompatibility between Zn2+ and organic matrix inhibits the solubility and activity of Zn2+ in the organic matrix, causing the heavy use of ZnO. This work develops a phase transfer agent with Zn2+-philic structure and oleophilic structure to increase the solubility of Zn2+ in the organic matrix. The phase transfer agent and Zn2+ form coordination interactions, while the hydrophobic chains of phase transfer agent and organic matrix form hydrophobic interactions. The above two interactions improve the solubility and activity of Zn2+ in the organic matrix, contributing to the formation of crosslinking network. Through the phase transfer agent strategy, we obtain the mechanically robust elastomers, and the samples with low ZnO content still maintain the superior properties. This work provides an efficient way to reduce ZnO content without sacrificing the performance of elastomers.

Enhanced Activity of Anti-oxidant Enzymes by Foliar Spray of Nanoscale Zinc Oxide under Drought Stress Conditions in Peanut (Arachis hypogaea L.)

Background: Zinc plays an important role in controlling both generations and also detoxifies free oxygen radicals that can damage membrane lipids and sulfhydryl groups. Zinc in particular has an action that prevents membrane damage induced by superoxide radicals that produce NADPH oxidase. The use of zinc oxide (ZnO) nanoparticles in agriculture had a significant impact on crop growth regulation, improved quality and improved stress tolerance. Hence, the current study aimed to study the foliar spray effect of nanoscale zinc oxide (25 nm mean particle size) at different concentrations and chelated bulk zinc suphate (ZnSO4) and comparable control (unsprayed) in peanut to investigate the oxidative stress induction and enhanced antioxidant enzyme activity (SOD, POD, CAT) under conditions of water stress. Methods: The experimental design was a randomized block design with two water regimes as main treatments viz., well watered (WW) and water stress (WS) conditions, eight foliar sprays along with unsprayed treatment (control) as sub treatments and 3 replications. The eight foliar spray treatments, includes nanoscale ZnO concentrations @ 10, 20, 40, 50, 100, 300, 1000 ppm, chelated bulk ZnSO4 (EDTA based) @ 0.1% (recommended dose). The antioxidant enzyme activity (SOD, POD, CAT) under conditions of both WW and WS was determined in the lab using UV spectrophotometer. Result: The results of pot culture experiment revealed that nanoscale ZnO at a concentration of 50 ppm increased biomass and pod yield and promoted antioxidant enzyme activity under water stress and well watered conditions compared to chelated bulk ZnSO4. Nanoscale ZnO showed increased activity under lower concentrations and inhibitory activity at higher concentrations that highlights the need for careful use of these particles in agriculture.

Adsorption of Pb(II) from Water onto ZnO, TiO2, and Al2O3: Process Study, Adsorption Behaviour, and Thermodynamics

This study is aimed at comparing the use of zinc oxide (ZnO), titanium dioxide (TiO2), and aluminium oxide (Al2O3) for removing lead ions from water through adsorption. The point of zero charge was obtained for ZnO, TiO2, and Al2O3 and was found to be 7.3, 7.1, and 9.0, respectively. The effect of pH, adsorbent dose, contact time, initial concentrations, and temperature was investigated in batch experiments. The optimal conditions obtained were 7, 2 g/L, 120 mins, 100 ppm, and 41°C, respectively, where the optimal removal efficiencies were 98.43%, 96.45%, and 85.50% for ZnO, TiO2, and Al2O3, respectively. In addition, analyses of adsorption kinetics, mechanisms, isotherms, and thermodynamics were performed. The adsorption kinetics of Pb(II) were compared to popular models, and it was found that the pseudo-second-order (PSO) model best fitted the Pb(II) uptake for all adsorbents at correlation coefficient ([Formula: see text]). The adsorption isotherms of Pb(II) were also compared to popular models, and it was found that the Pb(II) uptake by TiO2 and ZnO was well-described by the Langmuir model ([Formula: see text]) with maximum adsorption capacities of 55.04 and 58.88 mg/g, respectively. On the other hand, the behaviour of Al2O3 is described more accurately by the Dubinin-Radushkevich (D-R) model ([Formula: see text]), and the maximum adsorption capacity was 53.64 mg/g. The isotherm analysis proved that the limiting step of the adsorption process is the film diffusion mechanism. In addition, studying the heat of adsorption of Pb(II) implied that the adsorption is endothermic due to the positive values of enthalpy ([Formula: see text]) for all adsorbents. The absorbents were characterized using scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDX) to study the morphology of surfaces and the chemical characterization of the adsorbents to ensure that adsorption is achieved. ZnO showed better performance for the uptake of lead followed by TiO2 then Al2O3.

The Use of Zinc Oxide in a Public Healthcare Organization in Riyadh Region

Aim: The present study aimed to describe the use of zinc oxide in a public healthcare organization in Riyadh Region.&#x0D; Methodology: This is a retrospective study that includes reviewing the electronic prescriptions of zinc oxide among outpatients in a public healthcare organization in Riyadh Region.&#x0D; Results: More than 52% of the patients who received zinc oxide were males and the age of 79.41% of them was less than 10 years. More than 55% of the patients received zinc oxide for 1 week and 17.65% of them received zinc oxide for 2 weeks. All of the prescriptions were prescribed by residents (100.00%). Most of the prescriptions were written by emergency department (76.47%).&#x0D; Conclusion: The present study showed that zinc oxide was uncommonly prescribed in Al-Kharj. Additional studies are needed to explore the frequency of and the pattern of using it in different settings.

Tooth discoloration caused by endodontic treatment: A cross sectional study

Introduction: This cross-sectional study evaluated the influence of endodontic filling material, cervical limit of root filling, and tooth location on the color variation (ΔE00)from 1 to 60 months of follow-up. Materials and Methods: Color records were obtained from 70 participant’s who received 83 endodontic treatments. CIEL*a*b* color coordinates were measured on the homologous tooth, which was considered as baseline, and on endodontic treated teeth with a spectrophotometer. ΔE00 was calculated by the CIEDE2000 method at three conditions (condition 1: homologous tooth vs endodontically treated tooth after≤1 month; condition 2: homologous tooth vs endodontically treated tooth after >1–-12 months; condition 3: homologous tooth vs endodontically treated tooth after>12 months up to 5 years) for each variable. The zinc oxide and eugenol mineral trioxide aggregate or resin-based filling materials, dental cervix or ≥2 mm in the apical direction cervical limit of root filling and anterior or posterior tooth location were considered in the comparisons. Confidence intervals for the means (95% CI) were calculated,ΔE00 values and CIEL*a*b* individual color coordinates were compared for each pair of variables using the Student t test or Welch test (α = .05). Results: Greater ΔE00 values were generally observed in the condition 3 for cervical limit (ΔE00 = 10.7), use of zinc oxide and eugenol and mineral trioxide aggregate based filling materials (ΔE00 = 10.7), and anterior teeth (ΔE00 = 12.4). Only in the condition1, the ΔE00 values of the filling materials did not show statistical differences (P = .198). Conclusions: Higher ΔE00 values were yielded from zinc oxide and eugenol and mineral trioxide aggregate-based filling materials, anterior teeth, and dental cervix cervical limit of root filling. Clinical significance: Tooth discoloration yielded by endodontic materials and procedures is a challenge to clinical practice resulting in aesthetic problems and discomfort to both patient and professional, especially when it occurs in anterior teeth.

Imaging of Neurotransmitters and Small Molecules in Brain Tissues Using Laser Desorption/Ionization Mass Spectrometry Assisted with Zinc Oxide Nanoparticles.

Inorganic nanostructured materials such as silicon, carbon, metals, and metal oxides have been explored as matrices of low-background signals to assist the laser desorption/ionization (LDI) mass spectrometric (MS) analysis of small molecules, but their applications for imaging of small molecules in biological tissues remain limited in the literature. Titanium dioxide is one of the known nanoparticles (NP) that can effectively assist LDI MS imaging of low molecular weight molecules (LMWM). TiO2 NP is commercially available as dispersions, which can be applied using a chemical solution sprayer. However, aggregation of NP can occur in the dispersions, and the aggregated NP can slowly clog the sprayer nozzle. In this work, the use of zinc oxide (ZnO) NP for LDI MS imaging is investigated as a superior alternative due to its dissolution in acidic pH. ZnO NP was found to deliver similar or better results in the imaging of LMWM in comparison to TiO2 NP. The regular acid washes were effective in minimizing clogging and maintaining high reproducibility. High-quality images of mouse sagittal and rat coronal tissue sections were obtained. Ions were detected predominately as Na+ or K+ adducts in the positive ion mode. The number of LMWM detected with ZnO NP was similar to that obtained with TiO2 NP, and only a small degree of specificity was observed.

Effects of charge carrier density of ZnO film used in UV sensors: difficulties in measurement and rectification method

In this Technical Note, we demonstrate a rectification method to enable the use of zinc oxide (ZnO) films in conductometric ultraviolet (UV) sensors. The phenomenon of persistent conductivity has long impeded the employment of ZnO films as conductometric UV sensors and eventually yields photo-induced current saturation in the film. To address this problem, we propose measuring the change in current in a transient response compromising of an OFF period of 60 s followed by an ON period of 20 s. In addition, we have investigated the effects of temperature and relative humidity, and dyanamic response of the sensor for different UV intensities. The experimental result shows that this measurement technique allows the ZnO film to act as a conductometric sensor even after prolonged exposures.

Yield attributes of rice (Oryza sativa) as affected by integrated use of zinc oxide and zinc solubilizers

Rice (Oryza sativa L.) is the staple food for more than three billion people around the world. Zinc (Zn) deficiency is mostly found in lowland rice due to submergence condition which affect the yield adversely. In view of limited information, a pot experiment was conducted at Department of Soil Science and Agricultural Chemistry, Institute of Agricultural Sciences, BHU, Varanasi, UP during kharif, 2018-19 to evaluate the response of rice to different levels of zinc oxide (ZnO) in combination with zinc solubilizing microbes. Zn deficient soil was collected from Agricultural Research Farm, IAS, BHU which were treated with three different doses of ZnO (0, 2.5 and 5 kg ha-1) along with three types of microbial inoculation, viz. no inoculation (M0), Enterobacter clocae strain ZnPSBJ-6 (M1) and zinc solubilizing fungi (M2). It was found that ZnPSBJ-6 has increased the grain yield by 57.2% and 101.4% while treated with Z1 (2.5 kg ha-1) and Z2 (5 kg ha-1) respectively compared to Z0. Whereas, in case of zinc solubilizing fungi, grain yield has increased by 96.4% and 127.1% in case of Z1 and Z2 respectively. On the other hand application of Z1 and Z2 have significantly increased the average straw yield by 28.9% and 36.5% respectively over the control.