The promising properties of photonic crystal fibers (PCFs) have sparked the interest of a number of research organizations. Due to the PCF's air holes, liquid or gas samples can be inserted into ...them. This permits a well-controlled interaction between confined light and sensing samples, enabling the development of novel sensing applications. That was never conceivable with conventional optical fibers. PCF applications in sensing fields can be divided into physical sensors and biochemical sensors based on the parameter being measured. Physical sensors measure pressure, temperature, refractive index (RI), curvature, vibration, torsion, electric field, and displacement, among other physical characteristics. Biochemical sensors can detect chemical and biological (such as antibodies, cells, bacteria, enzymes, viruses, nucleic acids, etc.) substances. The measurement of the chemical RI is a crucial component of biochemical sensors. Due to their close relationship with biosensors, chemical sensors are commonly referred to as biochemical sensors. This article covers the detecting capabilities of surface plasmon resonance (SPR)-based PCF biochemical and physical sensors in addition to a variety of ways to enhance their sensing capacities.
► Degradation of different organic dyes with ZnS NPs under UV–Visible light. ► Capped ZnS NPs exhibit maximum degradation in comparison to uncapped and bulk ZnS. ► High degradation in capped NPs is ...explained with photoluminescence studies. ► The results are promising one to utilize solar energy for waste water purification.
Purification techniques like ozonization, chlorination and filtration have their own limitations of corresponding energy sources and harmful waste generation. However, heterogeneous photo catalysis is used for producing oxidative agent (hydroxyl radical) which has been used as an environmentally harmonious decontamination process. Such safe and low energy consumable photo catalytic system is required for purification of polluted water. Degradation of dyes is a standard method to check the photocatalytic activity of any type of photo catalyst. In this paper thioglycerol capped and uncapped ZnS nanoparticles are studied in detail for their photocatalytic activity and generation of electron hole pairs. Bromophenol blue, crystal violet and reactive red dyes were successfully photo reduced using ZnS nanoparticles after 3.0h of irradiation. Since the photocatalytic activity depends on the generation of electron hole pairs and the existence of different phases, we have tried to correlate the optical and morphological studies with these results to understand the phenomenon of photocatalytic activity at nanoscale. Though the Ultra violet irradiation can efficiently degrade the dyes, naturally abundant solar radiation is also very effective in the mineralization of dyes. Hence, it may be a viable technique for the safe disposal of textile wastewater into the water streams.
A novel method for the generation of the power-on-reset (POR) signal needed by the SOC is described. A POR signal is required for initialisation of the logical state in digital systems. To obtain an ...accurate trip point for the POR, generally a bandgap voltage reference is used along with additional logic. Such logic tends to limit the lowest possible trip point that can be achieved. The proposed implementation of POR is based on a modified bandgap circuit where a supply-dependent current is injected into the loop. In this case, the reference generation is not explicitly required and thus the trip point can be kept very close to the minimum supply required for the bandgap operation. This implementation also needs very small delay as the required delay is not dependent on supply ramp rates and can be made very small.
Highlighted are poorly investigated interactions that endophytes have with host plants, insect herbivores and with each other, and the diverse molecular mechanisms that might trigger similar chemical ...responses in both plants and endophytes. Elucidating such networks can enhance discovery of desirable endophytes and further sustain production of host plant compounds using the isolated endophytes. Display omitted
► Plants and endophytic fungi can occasionally produce similar bioactive compounds. ► Endophytes interact with coexisting endophytes, host plant, and insect herbivores. ► Early signaling mechanism influencing such endophyte interactions should be studied. ► Elucidating the molecular basis of such multifaceted interactions is also important. ► These distinct interactions can trigger similar chemical responses in the partners.
The biosynthetic potential of endophytic fungi has gained impetus in recent times owing to the continual discovery of fungal endophytes capable of synthesizing plant compounds. However, the sustained production of the desired plant compounds has not yet been achieved using endophytes. It is thus imperative to investigate the diverse interactions that endophytes have with coexisting endophytes, host plants, insect pests, and other specific herbivores. The precise role of these associations on the endophytic production of host plant compounds is mostly overlooked and open to future discoveries. Here, highlighted are the implications of the poorly investigated links and molecular mechanisms that might trigger similar chemical responses in both plants and endophytes. Elucidating such connections can not only enhance the understanding of evolution of complex defense mechanisms in plants and associated organisms, but also help in the sustained production of plant compounds using endophytes harbored within them.
•Nano-sized undoped and Cu (1.0–5.0%) doped ZnO has been synthesized by co-precipitation route.•PLE and PL spectra for doped ZnO NPs show large excitation and emission in visible region in comparison ...to undoped NPs.•Degradation of Crystal Violet dye with Cu doping and at various pH is discussed in detail.•Synthesized NPs at higher pH show remarkable modification in photocatalytic studies.•Synthesized NPs can be use to degrade dyes of variable pH without adjusting pH of dye solution.
Undoped and Copper (Cu) doped zinc oxide (ZnO) (Zn1−xCuxO, x=0.01, 0.02, 0.03, 0.04 and 0.05) nanoparticles (NPs) capped with (1.0%) Thioglycerol (TG) have been successfully synthesized by co-precipitation method. The synthesized samples have been characterized by X-ray diffraction (XRD), Energy dispersive spectroscopy (EDS), Transmission electron microscopy (TEM), Photoluminescence (PL) and UV–Visible spectroscopy. Incorporation of impurity ions in pure ZnO NPs leads to a shift the spectra for both excitation and emission to visible region as compared to pure ZnO. The photocatalytic activity of undoped and Cu doped ZnO photocatalyst were investigated by the degradation of Crystal Violet (CV) dye in aqueous medium under exposure of UV–Visible light irradiations. Firstly, degradation of CV dye has been studied with TG capped, undoped and Cu doped ZnO NPs synthesized at pH-8.0. From the results, it has been found that Cu doping concentration of 3.0% is optimal for higher photophysical and photocatalytic properties. When pH of optimum doped NPs was varied from 8.0 to 10.0, 78.7% to 96.5% of CV dye has been degraded after 3.5h. Further increasing the pH to 12.0 for optimum doped NPs, 100% dye degrades in 2.5h. This shows that the doping and pH has a pronounced effect on the photocatalytic activity of ZnO NPs. Loading of catalyst shows maximum photodegradation of CV dye at 3.0g/L of Cu (3.0%) doped ZnO at pH-12.0 for 10mg/L of CV dye. Kinetic studies shows that photo degradation of CV follow a pseudo first-order kinetic law. The reason for enhanced degradation with Cu doped NPs in comparison to undoped NPs has been described and discussed in this work.
Background Snakebite envenoming is a well-known medical emergency in the Terai of Nepal in particular. However, there is an epidemiological knowledge gap. The news media data available online provide ...substantial information on envenomings. Assessing this information can be a pristine approach for understanding snakebite epidemiology and conducting knowledge-based interventions. We firstly analyzed news media-reported quantitative information on conditions under which bites occur, treatment-seeking behavior of victims, and outcomes of snakebite envenomings in Nepal. Methodology/Principal findings We analyzed 308 Nepalese snakebite envenomed cases reported in 199 news media articles published between 2010 and 2022 using descriptive statistics, Wilcoxon, and Chi-square tests to know why and how victims were bitten, their treatment-seeking behavior, and the outcomes. These envenomated cases known with substantial information represented 48 districts (mostly located in the Terai region) of Nepal. These envenomings mostly occurred in residential areas affecting children. Generally, envenomings among males and females were not significantly different. But, in residential areas, females were more envenomed than males. Further, victims' extremities were often exposed to venomous snakebites while their active status and these episodes often occurred at night while victims were passive during snakebites indoors and immediate surroundings of houses. Snakebite deaths were less among referred than non-referred cases, males than females, and while active than passive conditions of victims. Conclusion/Significance The most of reported envenomed patients were children, and most envenomings were due to cobra bites. Consultation with traditional healers complicated snakebite management. In most cases, deaths that occur without medical interventions are a severe snakebite consequence in Nepal. Further, several deaths in urban areas and mountains and higher hills of Nepal suggest immediate need of snakebite management interventions in the most affected districts. Therefore, there is an urgent need to immediately admit Nepalese snakebite victims to nearby snakebite treatment centers without adopting non-recommended prehospital interventions. The strategies for preventing snakebite and controlling venom effects should also include hilly and mountain districts where snakebite-associated deaths are reported.
In the context of many applications, such as polymer composites, energy-related materials, sensors, ‘paper’-like materials, field-effect transistors (FET), and biomedical applications, chemically ...modified graphene was broadly studied during the last decade, due to its excellent electrical, mechanical, and thermal properties. The presence of reactive oxygen functional groups in the grapheme oxide (GO) responsible for chemical functionalization makes it a good candidate for diversified applications. The main objectives for developing a GO based nanohybrid proton exchange membrane (PEM) include: improved self-humidification (water retention ability), reduced fuel crossover (electro-osmotic drag), improved stabilities (mechanical, thermal, and chemical), enhanced proton conductivity, and processability for the preparation of membrane-electrode assembly. Research carried on this topic may be divided into protocols for covalent grafting of functional groups on GO matrix, preparation of free-standing PEM or choice of suitable polymer matrix, covalent or hydrogen bonding between GO and polymer matrix etc. Herein, we present a brief literature survey on GO based nano-hybrid PEM for fuel cell applications. Different protocols were adopted to produce functionalized GO based materials and prepare their free-standing film or disperse these materials in various polymer matrices with suitable interactions. This review article critically discussed the suitability of these PEMs for fuel cell applications in terms of the dependency of the intrinsic properties of nanohybrid PEMs. Potential applications of these nanohybrid PEMs, and current challenges are also provided along with future guidelines for developing GO based nanohybrid PEMs as promising materials for fuel cell applications.
We report an experimental study of a Cooper pair splitter based on ballistic graphene multiterminal junctions. In a two transverse junction geometry, namely the superconductor-graphene-superconductor ...and the normal metal-graphene-normal metal, we observe clear signatures of Cooper pair splitting in the local as well as nonlocal electronic transport measurements. Our experimental data can be very well described by our beam splitter model. These results open up possibilities to design new entangled state detection experiments using ballistic Cooper pair splitters.
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