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Composts are considered to be one of the best soil amendments. However, the effects of composts with added polymeric materials on soil physical, hydraulic, and micromorphological properties have not been widely discussed. Changes in soil physical properties influence the numerous services that soils provide. We studied the impacts of composts with the addition of three different polymers (F1–F3) produced from polyethylene and thermoplastic corn starch on the physical, hydraulic, and micromorphological properties of two soils, a Cambic Phaeozem and a Luvic Phaeozem. Applying composts with polymers had limited or no significant effect on soil bulk density and porosity, but increased the field water capacity by 18%–82% and 3%–6% and the plant-available water content by 15%–23% and 4%–17% for the Cambic Phaeozem and Luvic Phaeozem, respectively. The application of composts with polymers had a greater effect on the Cambic Phaeozem than on the Luvic Phaeozem. It was suggested that the use of modified composts led to changes in soil physical properties and micromorphological features and this effect was dependent on the compost application rate. Composts made with the addition of composite synthetic and natural material-derived polymers during composting were found to be a composite mixture that can be successfully used in agriculture.

Efficient storage of hydrogen is one serious impediment in using H2 as an alternate clean fuel, at a larger scale, in the context of alarming levels of global warming and fast depleting fossil fuel resources. Metal nitrides such as Li2N4, Na2N4 and K2N4 using density functional theory with PBE1PBE and B3LYP functional and 6-31G (d,p), 6–31 ++ G (d,p) and 6–311 ++ G (d,p) as basis sets. This has revealed that doping of alkali metal atoms on the nitride systems increases their hydrogen adsorption ability, due to the electron transfer that occurs from the metal atom to the nitrogen surface. The charged surface created around the metal atom is found to enhance the hydrogen adsorption capacity of the complex from 9 to 16.79wt% with an average binding energy from 0.06 to 0.30 eV/H2. Various conceptual reactivity descriptors, bond parameters, Gibbs free energy change (ΔG) and energy gap values support the idea that the stability of the complex increases on hydrogen uptake. Efficient storage of hydrogen is one serious impediment in using H2 as an alternate clean fuel, at large scale, in the context of alarming levels of global warming and fast depleting fossil fuel resources. Herein, we report theoretical studies on some novel metal nitrides in order to probe its hydrogen storage potential. M2N4 systems (where M = Li, Na, K) can store hydrogen around 5–12 H2 molecules with an gravimetric density of 9–16.79 wt% and an average binding energy in the range of 0.06–0.30 eV/H2. It was found that among all the three metal nitrides Li2N4 is found to possess highest binding energy and energy gap, whereas K2N4 adsorbs maximum number of H2 molecules.

The work presented in this paper aims to study the effect of nanoparticles dispersed in waste cooking oil (WCO) biodiesel on the thermal performance characteristics of VCR, one cylinder compression ignition (CI) engine. The naoparticles considered are Cerium Oxide (CeO2) and Magnesium Oxide (MgO) is mixed with the different biodiesel-diesel blends of 20%, 40% and 60% of WCO (B20, B40, B60) using ultrasonicator. The thermal performance characteristics are investigated by conducting test at 1500 rpm constant speed and load varying from 25% to 100% load of engine with an interval of 25% load. The experimental test results reveals that the improvement in performance characteristics of VCR engine due to the addition of Cerium Oxide (CeO2) and Magnesium Oxide (MgO) nanoparticles to different blends of WCO biodiesel compared to that of neat diesel.

The mixed nano-ferrites materials Cu0.6Zn0.4HoxFe2−xO4 (0.00 ≤ x ≤ 0.12) were prepared via the sol–gel auto combustion technique. The TGA curve established the annealing temperature (500 °C) for phase formation. The single exothermic peak on the DSC plot occurred at 341 °C temperature. XRD patterns of these nano ferrites verified single phase formation of the FCC cubic structure. The lattice constant a was increased from 8.4244 to 8.4419 A and then its value decreased to 8.4319 A. Crystallite size was found in the range of 7 to 16 nm. The surface morphology of the samples was observed from the scanning electron microscope (SEM) images. The grain size was found within the range of 90 nm to 106 nm. Energy-dispersive X-ray (EDX) results showed the significant substitution of Ho in Cu–Zn spinel ferrites. Dielectric parameters such as dielectric constant, dielectric constant factor, and tan loss depicted a decreasing trend with Ho3+ ions concentration. The single-domain ferrimagnetism is confirmed by the squareness ratio, which is

Novel Zn0·95Mn0·05O and Zn0·9Mn0.05M0.05O (M = Al, Bi, Sr, Ag) nanocrystals were prepared via the co-precipitation technique. The X-ray diffraction pattern confirmed the substitution of Mn, Al, Bi, Sr, and Ag dopants without altering the basic ZnO structure. The microstructural study was performed by employing the Scherrer plot, Williamson-Hall, and SSP methods. The energy bandgap calculated from UV–vis spectra using different methods observed red-shifted by co-doping. The other optical parameters were also studied and discussed in detail. The FTIR spectra confirmed the presence of Zn–O, and Zn-M–O vibrational modes. Raman spectra demonstrated the presence of ZnO phonon modes, and the Raman shift exhibited the structural defects induced by dopants. The PL spectra showed strong NBE and DLE in the UV and visible region due to extrinsic defects. The IV measurements exhibited the enhancement in the electrical conductivity of ZnO by co-doping. The photocatalytic activity was performed under direct sunlight for methyl orange and methylene blue dyes, and the enhanced degradation efficiency was achieved by co-doping. Furthermore, this article enhances the understanding of tuning the physical properties of ZnO by co-doping and introduces a new class of sunlight-driven photocatalysts.

Economic integration in the form of Belt and Road Initiative project opens many opportunities and hazards, especially of the participating nations’ environment. The current study attempted to empirically test the economic and energy usage (renewable and non-renewable) impact on some selected countries of belt and road projects. For this purpose, the panel data set of twenty-four emerging economies of belt and road projects was selected from 1995 to 2014. The autoregressive distributed lags technique of econometric applied to determine the effect of renewable and non-renewable energy, GDP and GDP2 for EKC, and gross fixed capital formation on carbon emission in the selected countries of Belt and Road Initiative project. The outcomes of this study confirm the existence of EKC in these underlined countries. Here, fossil fuel-based energy consumption is a source of environmental degradation, while renewable and clean energy usage can help sustain environmental conditions without affecting economic growth progress. Capital fixed formation in these economies can enhance economic growth and help to sustainable environmental conditions in the belt and road countries. Thus, based on these empirical outcomes, this study suggests economic and financial assistance in green renewable energy sources and clean technological innovation to enhance economic benefits of Belt and Road Initiative project without compromising the environmental conditions of the region.

Hematite (α-Fe2O3) nanoparticles were synthesized by modified solution combustion method using a mixture of hexamethylenetetramine (HMTA) and glycine fuels at fuel to oxidant molar ratio (ϕ = 1) and fuel (HMTA) to fuel (glycine) weight ratio (1:3). DC-conductivity and dielectric studies of (α-Fe2O3) nanostructures were reported as a function of temperature. Above room temperature (RT), the conductivity showed an increasing trend with temperature which confirmed the semiconducting behaviour of the material. The conductivity behaviour followed Motts law which confirmed the three dimensional variable range hopping (3D VRH) mechanism in the synthesized system. Dielectric studies were carried out at room temperature with frequency range (1000 Hz to 1.5 MHz) as well as varying temperature (100 °C to 400 °C) at different frequencies (0.1 MHz, 0.3 MHz, 1 MHz, 1.3 MHz, and 1.5 MHz).The dielectric permittivity (є’)and tangent loss (tan δ) was found to increase with increase in temperature. In this synthesised material low value of dielectric loss was observed which depicted these materials as potential candidates for microwave applications. More than that studied material was characterised by Raman spectroscopy which revealed that seven active Raman modes were present with different intensities, namely two “A1g” modes (225 and 498 cm−1) and five “Eg” modes (247, 293, 299, 412 and 613 cm−1). The most representative band present in the synthesised iron oxide nanoparticles was found at 225 cm−1.

In the last decade, radiation physics brought about a revolution in health science by improving scientific equipment and useful methodologies for measurement. Human beings are affected by ionizing radiations that radiate from radioactive elements. The quantity of radioactive elements is different inside and outside the earth’s surface. Soil and water are exigencies of human lives which are contaminated by radioactive elements. These radioactive elements enter into the human body through drinking, eating and breathing. On reaching hazardous limits in the human body, these radioactive elements cause stomach cancer, lung cancer and leukemia. Measurement of radioactive elements in soil and water is helpful in monitoring the health issues caused by exposure to these elements. In Iraq, numerous studies about natural radioactivity, radon concentration and physiochemical parameters have been conducted by different researchers, of which most of the studies were conducted in Barsa, Nasirya, Najaf, Karbala, Baghdad, Balad, Kirkuk, Erbil, Mosul and Dohuk cities. This article aims to review and compile the studies conducted in these cities of Iraq from 2011 to 2019. In most articles, high-purity germanium (HPGe), RAD7 and CR-39 detectors are used for radioactivity and radon measurement. These cities are located in the low-high folded and Mesopotamian zones. From this study, it can be concluded that radon concentration in soil and water was greater in the Mesopotamian and lower in the low-high folded zones. Higher concentrations of natural radioactivity in water and soil were found in the low-high folded zone in Iraq. However, most of the conducted studies show that concentrations of radon and natural radioactivity are above the permissible limits recommended by the International Commission on Radiological Protection (ICRP) and World Health Organization (WHO). The values of physiochemical parameters were found to be greater in the Mesopotamian zone, but overall they are not above the permissible limits.

Novel tri-phase ZnO-Yb2O3–Pr2O3 heterostructured nanocomposite was synthesized by the co-precipitation technique, and its application as an efficient antibacterial agent and photocatalyst were studied. The grown sample was characterized by XRD, FTIR, Raman, UV–vis, IV, and SEM to explore the structural, optical, electrical, and morphological properties. The XRD pattern revealed the presence of diffraction peaks related to ZnO (hexagonal), Yb2O3 (cubic) and Pr2O3 (hexagonal) in the nanocomposite. The microstructural parameters were calculated using Scherrer plot, W–H and SSP methods. The optical energy bandgap was 2.8 eV determined from UV–vis spectroscopy, specified that it could be used as a proficient photocatalyst under sunlight illumination. The FTIR spectrum confirmed the presence of characteristics vibrational bands associated with the Zn–O, Pr–O, and Yb–O bond vibrations at 463, 535 and 562 cm−1, respectively. The Raman spectrum exhibits the fundamental optical phonon modes related to ZnO, Yb2O3 and Pr2O3 in the nanocomposite, confirmed the successful formation of the nanocomposite. IV measurement showed the high electrical conductivity of grown nanocomposite. SEM images revealed that nanocomposite has a porous type morphology with high agglomeration. The antibacterial activity was performed against S. aureus (G-positive) and E. coli (G-negative) bacteria. The zone of inhibition (ZOI) shown that the nanocomposite has the highest activity against S. aureus with a ZOI 31 mm. The photocatalytic activity of the ZnO-Yb2O3–Pr2O3 nanocomposite was carried out for the degradation of MB dye under sunlight irradiation, revealed 99.8% degradation in 60 min. The effect of several operational parameters such as catalyst dose, dye concentrations, pH of reaction along with reusability and radical trapping experiments were performed and discussed in detail. A possible schematic model was proposed to elaborate the photocatalytic mechanism. Furthermore, this work introduces a novel material to enhance the photocatalytic and antibacterial activity for environmental and biomedical application.

The genus Macrocentrus Curtis, 1833 is extensively dispersed with 238 species known worldwide. Including this new species, eight species of Macrocentrus are known from India. This genus is characterized by following characters: Antenna often about as long as or somewhat longer than the body (but sometimes distinctly shorter), with 24-61 segments, apical segment with distinct spine or without a spine. In the present study a new braconid, Macrocentrus hayati sp. nov. is described and illustrated from Jammu and Kashmir (UT), India. Specimens were collected from the grass (Cynodon) and weeds near the vegetables like brinjal, potatoes and beans through net sweeping. The collected material was transferred to glass vials containing 70% ethyl alcohol and brought to the laboratory for further studies.The study will help to boost the knowledge of Braconid parasitoids (living weapon) which play a key role in controlling the harmful pests, ultimately resulting in the increase of the yield of crops and other economic commodities like food grains.

Novel Zn0.90Co0.10O and Zn0.90Co0.05M0.05O (M = Ca, Ba, Cr, Pb) nanocrystals were synthesized by co-precipitation method and studied its structural, optical and electrical properties along with their photocatalytic activity. The XRD confirmed that Ca, Ba, Cr, and Pb have been incorporated without modifying ZnO hexagonal wurtzite structure. The microstructural parameters were calculated using Scherrer, W–H, and SSP methods. FTIR confirmed the existence of Zn–O vibrational modes. UV–vis spectra used to calculate the energy bandgap by using Tauc’s plot, Energy equation, Vegard’s law, and Derivative method. Optical parameters such as Urbach energy, refractive index, dielectric constant, extinction coefficient and optical conductivity were also studied. The IV measurements demonstrated that electrical conductivity was increased significantly by co-doping. The photocatalytic activity for the decolorization of methylene blue (MB) and methyl orange (MO) dyes under sunlight revealed the highest degradation efficiency for co-doped nanocrystals against MB as compared to MO in 100 min illumination. The grown nanocrystals are propitious sunlight driven photocatalyst to eradicate organic toxins.

Structural, electronic, magnetic and optical properties of MFe2O4 (M = Mn, Co, Ni) ferrites are studied by first-principles approach. MFe2O4 ferrites exhibit stable structure in ferromagnetic phase. Density of states (DOS) and electronic band structures reveal that all ferrites show favorable spin polarization behavior in applications point-of-view. The CoFe2O4 ferrite shows half-metallic ferromagnetic characteristics with direct band gap, Eg = 0.713 eV in spin↑ state while NiFe2O4 shows spin gapless ferromagnetic behavior (with Eg = 0.0 at EF) in spin↑ state. The MnFe2O4 ferrite is found to have magnetically conducting behavior. MFe2O4 (M = Co, Ni) ferrites indicate 100% spin polarization at EF. The electronic band structures reveal electronic transition between O-2p to Fe-3d states in valence band (VB) or d-d transition between Fe-3d valence and conduction bands. The optical properties shows that the MFe2O4 (M = Mn, Co, Ni) ferrites exhibit transparent behavior to ultraviolet light indicating their suitability for use in optical filters and sensors.

In this article, ternary oxide NiO-CdO-ZnO nanocomposite along with pure NiO, CdO and ZnO were prepared by the homogeneous co-precipitation method. The XRD pattern confirmed the formation of nanocomposite with NiO (cubic)–CdO (cubic)–ZnO (hexagonal). The volume fractions were 38% NiO, 6% CdO and 56% ZnO phase in nanocomposite determined by direct comparison method. Crystallite size and lattice strain were calculated using Scherrer plot, Williamson-Hall and Size-Strain plot methods. The UV–vis was used to study optical properties such as bandgap (Eg), refractive index (n), extinction coefficient (k), optical conductivity (σopt) and dielectric constants (er, ei). FTIR and Raman analyses have confirmed the successful formation of NiO-CdO-ZnO nanocomposite. The current-voltage measurements revealed that nanocomposite has high electrical response. SEM images shown that nanocomposite has roughly spherical morphology and EDX described that Zn has higher concentration than Ni and Cd. PL spectra of nanocomposite demonstrated the emission bands associated with new energy levels induced by defects. The photocatalytic activity of grown nanocomposite against rhodamine B (RhB) and methylene blue (MB) dyes under sunlight revealed high degradation efficiency 99% for RhB and 98% for MB in 60 and 90 min illumination respectively, indicated that grown nanocomposite is a propitious sunlight-driven photocatalyst to eliminate organic toxins.

The residual effect of tobacco biochar (TB ≥ 500°C) mono and co-application with Ca-hydroxide (CH), Ca-bentonite (CB) and natural zeolite (NZ) on the bio-availability of trace elements TE(s) in alkaline soils has not been deeply studied yet. A pot study that had earlier been investigated TB mono and blended with CH, CB and NZ on the immobilization of Pb, Cu Cd, and Zn by Chinese cabbage. Maize crop in the rotation was selected as test plant to assess the residual impact of amendments on stabilization of Pb, Cu Cd, and Zn in mine polluted (M-P), smelter heavily and low polluted (S-HP and S-LP, respectively) soils. The obtained results showed that stabilization of Pb, Cd, Cu and Zn reached 63.84% with TB + CB, 61.19% with TB + CH, 83.31% with TB + CH and 35.27% with TB + CH for M-P soil, 36.46% with TB + NZ, 38.46% with TB + NZ, 19.40% with TB + CH and 62.43% with TB + CH for S-LP soil, 52.94% TB + NZ, 57.65% with TB + NZ, 52.94% with TB + NZ, and 28.44% with TB + CH for S-LP soil. Conversely, TB + CH and TB alone had mobilized Pb and Zn up to 19.29% and 34.96% in M-P soil. The mobility of Zn reached 8.38% with TB + CB and 66.03% with TB for S-HP and S-LP soils. The uptake and accumulation of Pb, Cd, Cu and Zn in shoot and root were reduced in three polluted soils. Overall, the combination of TB along with CH, CB and NZ has been proven to be effective in Pb, Cd, Cu and Zn polluted mine/smelter soils restoration.

The aim of this study was to assess the solubility of phosphorus from rock phosphate incubated with farmyard manure under laboratory condition. The treatments were factorial combination of three rates each of RP (0, 2, and 4 tons ha-1) and farm yard manure (0, 10 and 20 tons ha-1). These treatments were applied to 100 g soil contained in plastic vials with three replications. Seven such sets of 27 vials each were prepared to represent seven incubation periods namely 0, 15, 30, 45, 60, 75, and 90 days. The results showed that Olsen -P improved significantly with increasing rate of rock phosphate from 0 to 4 tons ha-1 and that of farmyard manure from 0 to 20 tons ha-1. Initial available P content of soil was 4.59 mg kg-1 which enhanced up to 10.55 mg kg-1 as a result of 90 days incubation. Addition of rock phosphate and farmyard manure increased it to maximum value of 23.03 mg kg-1 with incorporation of rock phosphate at 4 tons ha-1 and farmyard manure at 20 tons ha-1. Thus, positive response of rock phosphate and farmyard manure was clearly evident on Olsen-P values due to enhancement of soil organic matter. It is concluded that there is potential for utilization of local rock phosphate by solubilising the P using farmyard manure. Soil incubation for the prolonged period of 90 days with rock phosphate and farmyard manure helped to enhance the solubility of P from rock phosphate. It is recommended that further experiments may be performed along with different bio-char, vermicompost, organic acids etc. which can help solubilise P from rock phosphate under field trials. For the first time, the feasibility of using agricultural fertilizer (manure) to increase the solubility of phosphorus from rock phosphate is experimentally substantiated. The practical value of this study is to achieve two effects simultaneously, namely, improving the fertility of agricultural lands depleted in phosphorus and utilizing agricultural fertilizer (manure).

In this work, nickel-doped magnetite nanoparticles (NPs) are synthesized by a modified solution combustion method and subsequently annealed at different temperatures. We report the structural, optical, dielectric, electrical, and magnetic properties of nickel-doped magnetite nanoparticles (NPs) annealed at 800°C, 1000°C, and 1200°C for 180 min. X-ray diffraction is utilized to explore the structural properties of the prepared magnetic nanoparticles. The surface morphology indicates that the particles annealed at 800°C and 1000°C are spherical, while particles annealed at 1200°C are polyhedral in shape and have uniform distribution. Energy-dispersive spectroscopy reveals the presence of the elements Ni, Fe, and O in the synthesized nanoparticles. The optical spectra obtained from UV–visible spectroscopy reveal that heat-treated synthesized samples have allowed a direct energy band gap. Also, the optical band gap shows a decreasing trend from 1.736 eV to 1.679 eV, while Urbach energy shows an increasing trend from 0.279 eV to 0.539 eV, with increasing annealing temperature. Photoluminescence spectra show a small redshift in band-edge emission from 433.77 nm to 440.12 nm with an increase in annealing temperature from 800°C to 1200°C. The dielectric studies are carried out at (1) varying frequency (20 Hz–2 MHz) at room temperature and (2) varying temperature (100–400 K) at constant frequency of 100 kHz. Both temperature- and frequency-dependent dielectric studies show an increase in the dielectric constant and dielectric loss with an increase in annealing temperature. Also, the conductivity increases with increased temperature in all studied samples, indicating semiconducting behavior, and increased conductivity is observed with increased annealing temperature. The conductivity behavior follows Mott's law, confirming the variable-range hopping mechanism in all samples. Magnetic measurements show high coercivity of 199.12 Oe and high remanent magnetization of 27.35 emu/g at lower annealing temperature. Thus, the magnetic properties of the synthesized ferrite nanoparticles can be tuned by adjusting particle size through annealing temperature.

The homogeneous precipitation method was used to synthesis ZnO, NiO nanoparticles and ZnO–NiO nanocomposites with and without surfactants, sodium dodecyl sulphate (SDS) and hexamethylenetetramine (HMT) to alter the composition of nanocomposites. The grown samples were annealed at 300 °C and 600 °C for 2 h to convert the hydroxides into their oxides. To investigate the effect of different composition on the crystal growth, particle size, morphology, structural and optical properties of nanocomposite, X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), UV–vis spectroscopy (UV), Raman spectroscopy and Scanning electron microscopy (SEM) were employed. X-ray quantitative phase analysis was used to estimate the volume fractions of ZnO and NiO phases in grown nanocomposites. The percentage of ZnO phase is more than NiO phase in all nanocomposites and strongly depends on composition. The structural parameters like lattice constants (a, c), bond-length (l), unit cell volume (v), density (ρ), d-spacing (d), strain (e) and dislocation density (δ) of ZnO, NiO and ZnO–NiO nanocomposites were calculated. The Scherrer, Williamson-Hall and Size-Strain analysis were used to calculate the crystallite size and lattice strain. The optical parameters such as optical absorption coefficient (α), bandgap (Eg), skin depth (δ), optical density (Dopt), extinction coefficient (k), refractive index (n), optical conductivity (σopt) and dielectric constants (er, ei) were studied from UV–vis spectra. The nanocomposites grown in this study provide an opportunity of band tuning for better functional performance for device fabrication compared to the basic metal oxides. FTIR characteristic peaks and Raman fundamental optical phonon modes confirmed the formation of ZnO, NiO and ZnO–NiO nanocomposites. SEM analysis revealed that ZnO–NiO nanocomposites have different surface morphology by adding different surfactants.

The present study was designed to investigate the stimulatory effects of different doses (0.1 to 2.5 μM) of thidiazuron (TDZ) on in vitro shoot induction and proliferation of mature nodal explants of Tecoma stans. Of the tested concentrations, 2.0 μM TDZ proved to be optimal for maximum regeneration (91%) with a mean shoot number of 5.6 ± 0.67, and length of 2.38 ± 0.08 cm, after 4 wk of incubation. To determine the negative effects of prolonged TDZ exposure, after 4 wk of incubation at optimized level of TDZ, the cultures were transferred to a secondary medium either lacking plant growth regulators or supplemented with benzyladenine (BA) alone, or in combination with different auxins (indole-3-acetic acid, indole-3-butyric acid, or α-naphthalene acetic acid; NAA). Among the tested concentrations, 2.5 μM BA in combination with 0.5 μM NAA yielded the maximum mean shoot number (16.60 ± 0.40), and average shoot length (4.76 ± 0.15 cm) after 4 wk of culture. The best rhizogenesis (93%) was achieved on ½ MS medium containing 1.5 μM NAA, with a mean root number of 7.60 ± 0.40 and length of 4.11 ± 0.23 cm, after 4 wk of incubation. The micropropagated plantlets were successfully acclimatized and hardened off in Soilrite™ with a 90% survival rate. The plantlets grew well with normal growth, flowering and showed, by gas chromatography–mass spectroscopy, an increase in the number of bioactive compounds compared with the donor plant. This is the first report on T. stans in vitro regeneration using TDZ.

This work presents theoretical modeling of some systems, using density functional theory (DFT), for enhancing the photoresponse of a dye-sensitized solar cell. The optimization of the dye (NKX 2587) as well as the dye derivatives was carried out using B3LYP and 6-311g (d,p) level of theory, using DFT as incorporated in Gaussian 03 level of programming. The HOMO-LUMO energy gaps are lower for (CdSe)13 -Dye-(TiO2 )6 multijunction systems in comparison with both the isolated dyes as well as dye-TiO2 systems. The absorption peaks were found to be mostly red-shifted for (CdSe)13 -Dye-(TiO2 )6 multijunction systems with respect to the Dye-TiO2 systems, indicating the enhancement of the absorption behavior of the dye sensitizer by its interaction with the CdSe framework. The results thus indicate some sort of co-sensitization of the TiO2 by the dye sensitizer as well as the CdSe quantum dot and are hence expected to increase the efficiency of the solar device. © 2019 Wiley Periodicals, Inc.

We assessed the efficacy of Ca-bentonite (CB) alone and combined with Ca-hydroxide (CH), tobacco biochar (TB), and zeolite (ZL) aiming to immobilize Cu and Pb and decrease their bioavailability and uptake by pak choi followed by maize in a mining contaminated soil. The CB alone was able to decrease the availability and uptake of Cu and Pb by pak choi and maize. The mono- and multi-combination of CH, TB, and ZL with CB showed contradictory impact on the availability and uptake of Cu and Pb as compared to the mono-application of CB. The combination of CB with ZL and CH + ZL reduced the uptake of Pb by pak choi and maize, while the combination of CB with TB and ZL reduced the uptake of Cu by pak choi and maize as compared to the mono-application of CB. The co-application of CB with CH increased the phytoextraction of Cu by maize and Pb by pak choi shoots as compared to the mono-application of CB. We conclude that modified clays such as CB alone or combined with ZL, TB, and/or CH might be suitable candidates for phytomanagement of Cu and Pb contaminated soils.

In aqueous systems, heavy metal ions, when present in excess than permissible limits, are dangerous for human beings and aquatic life. Heavy metals cannot be degraded. Rather, they accumulate in living organisms either directly or through the food chain. Inside the body, metal ions can be converted to more toxic forms or can directly interfere with metabolic processes. As a result of metal toxicity, various disorders and damage due to oxidative stress triggered by metal ions have been witnessed. Toxic effects of metallic pollution coupled with the need of pure water for the survival and sanitation have thus prompted researchers to take every possible step to uphold the quality of water. In this regard, various strategies have been developed for the detection and the removal of metal ions from aqueous systems. Here we review metal-free water and methodologies used for rapid detection at low levels. Also, the application of benign materials and methods for metal removal from aqueous systems is detailed. Electrochemical methods, especially stripping and cyclic voltammetry, are commonly used methods for detection, while adsorption and ion exchange methods are quite effective for removal.

Comparative effect of meta-topolin and other cytokinins was assessed to develop an efficient and reliable regeneration protocol for Tecoma stans, using mature nodal explants. The morphogenic effect of benzyl adenine (BA), kinetin (Kin), meta- topolin (mT) and 2-iP (2-iso pentenyl adenine) at various concentrations (1.0–10 µM) was studied individually or in combination with auxins (IAA, IBA or NAA). Superior multiplication rates were achieved on MS medium supplemented with mT and NAA. Of the tested combinations, maximum shoot regeneration (95%), mean shoot number (19.6 ± 0.60) and length (5.26 ± 0.73 cm) was recorded on MS medium supplemented with 7.5 µM mT + 0.5 µM NAA after 8 weeks of incubation. Among the different auxins employed for in vitro root induction, 92.5% microshoots rooted on MS medium enriched with 1.0 µM IBA with 10.8 ± 0.20 mean root number and 5.62 ± 0.17 cm length after 4 weeks of incubation. The acclimatized plants grew well in green house with 90% survival rate. The gas chromatography–mass spectrometry (GC–MS) analysis of ethanol leaf extract of in vitro-raised plants yielded a higher number of compounds than control plant. The assessment of genetic fidelity among regenerants, using ISSR markers did not reveal any somaclonal variation. Therefore, the protocol developed appears to be simple and reliable for mass production of clones with higher diversity of secondary metabolites. Our studies based on interaction of mT with auxins for better shoot proliferation will undoubtedly be helpful in understanding many developmental processes in plant tissue culture. The regenerated plantlets survived well under field conditions and no somaclonal variation was detected. This study proved that in vitro raised plants are superior for the production of higher diversity of secondary metabolites than in vivo plant. Thus, our findings are helpful in generating an efficient micropropagation system for mass scale production of plants with higher diversity of bio-active molecules without losing their genetic stability.

Mountain pine beetle (Dendroctonus ponderosae Hopkins, Coleoptera: Curculionidae, Scolytidae) has recently invaded novel jack pine (Pinus banksiana Lamb., Pinales: Pinaceae) forests in western Canada. Jack pine seems to be a suitable host for mountain pine beetle, but how growing conditions influence jack pine’s quality as a host, and hence, its susceptibility for mountain pine beetle, is unknown. Specifically, how soil nutrient concentrations and available water holding capacity (AWHC) affect jack pine quality should be investigated. Host plant quality is an important determinant of mountain pine beetle host colonization and reproduction and is usually assessed by primary (nutrients) and secondary (defense chemistry) constituents of host phloem. We evaluated mountain pine beetle host acceptance and brood production by recording the percentage of female mountain pine beetle that entered the phloem and oviposited in 30 jack pine bolts from two sites that differed in soil nutrient concentrations and AWHC. We also compared the concentrations of phloem nutrients and defense monoterpenes among the selected trees and found that trees at the Low AWHC site had higher amounts of nitrogen, phosphorus, and potassium. Monoterpene concentrations did not differ among trees at the two sites. Host acceptance by and brood production of mountain pine beetle were greater in bolts from the Low AWHC site. We conclude that AWHC of the soil may influence mountain pine beetle host acceptance and brood production through altering host plant quality, particularly nitrogen in the phloem, and will potentially influence any further range expansion of the beetle in eastern North America.

The structural, mechanical, electronic and magnetic properties of quaternary YFeCrX (X = Al, Ga, In, Si, Ge, Sn, P, As, Sb) Heusler alloys are reported. The structural stability, electronic and magnetic properties of Heusler alloys are studied by implementing spin polarized density functional theory (DFT). All alloys with cubic structure are found stable in ferromagnetic phase. Among the YFeCrX alloys, the YFeCrGa, YFeCrSi and YFeCrSb alloys exhibit high values of bulk moduli. The calculated cubic elastic constants show that all alloys fulfill the mechanical stability criteria. The band structures (BSs) and density of states (DOS) shows half metallic (HM) behavior of alloys. Among the alloys, the YFeCrSi, YFeCrGe, YFeCrSn, YFeCrP and YFeCrSb alloys exhibit indirect band gap in S↓ channel and show 100% spin-polarization. The YFeCrX (X = Si, Ge, Sn, As, Sb) alloys obey the Slater - Pauling rule, μ T o t a l = Z T o t a l - 18 while the YFeCrP alloy found to follow the Slater-Pauling rule, μ T o t a l = 24 - Z T o t a l . Thus, the alloys which have high magnetic moment are expected to have high Curie temperature T C suitable for applications in spintronic devices.

Studies with conifer-infesting bark beetles commonly use bolts cut from trees to evaluate the effects of host tree quality on various aspects of insect biology. Yet, whether host quality changes between live trees and bolts cut from these trees has not been assessed. Particularly, changes in concentrations of defense chemicals (such as monoterpenes) and nutrients (such as nitrogen and carbon) have not been compared between live trees and their cut bolts. To determine whether monoterpene and nutrient concentrations differ after cutting, jack pine (Pinus banksiana Lamb.) trees in Lac La Biche (Alberta) were selected and sampled for phloem tissue. Then, these trees were harvested into two bolts per tree and stored at 4 °C for 3 and 6 months. Phloem was sampled from both live trees and bolts 3 and 6 months after storage. We found that major monoterpenes of jack pine were higher in phloem from bolts than from live trees. Storage time did not affect the results. Furthermore, some nutrients including nitrogen were also higher in bolts and varied between storage times. We conclude that researchers should be aware of the observed changes in the host quality that may have positive or negative effects on the development and behavior of bark beetles under observation.

The environmentally safe disposal of the large quantity of orange peels waste produced each day causes economic and environmental problems, which after conversion into biochar via pyrolysis technique might be used as an effective soil amendment. In this study, a 90-day incubation experiment was conducted to investigate the effects of orange peel waste and waste-derived biochar amendments on greenhouse gas emissions (GHG), soil biochemical properties, and soil enzyme activities. There were five treatments with different amendment levels: control without an amendment (Control), orange waste 1% (W1), orange waste 2% (W2), orange waste biochar 1% (B1), and orange waste biochar 2% (B2). The results showed that, compared with control, the amendments decreased cumulative N2O emissions by 59.2% (B2), 45.2% (B1), 20.6% (W2) and 10.2% (W1), respectively; and increased cumulative CH4 emissions by 81.7% (W1), 84.4% (W2), 75.8% (B1) and 74.9% (B2), respectively. Cumulative CO2 emissions decreased for the B1 (29.3%) and B2 (43.5%) over the waste treatments. While soil pH, SOC, nitrate nitrogen (NO3--N) and enzyme activities (urease and catalase) were significantly increased with the passage of time from the biochar amendments, ammonium nitrogen (NH4+-N) and invertase activities did not show this trend with time. Our study suggests that orange peel waste conversion to biochar should be a viable alternate method of disposal since land application resulted in reduced GHG and improvements in soil fertility.

Herein, we report the electrochemical detection of heavy metal ions such as Pb(II), Cd(II) and Hg(II) ions while using glutathione coated hollow ZnO modified glassy carbon electrode (Glu-h-ZnO/GCE). An excellent voltammetric response of the modified electrode towards these metal ions was observed by different voltammetric techniques. Among the different target metal ions, a selective electrochemical response (sensitivity = 4.57 μA μM−1) for the detection of Pb(II) ions was obtained with differential pulse voltammetric (DPV) measurements. Besides, under optimal experimental conditions and in the linear concentration range of 2–18 μM, a very low detection limit of 0.42 μM was obtained for Pb(II) ion. The observed electrochemical behaviour of Glu-h-ZnO/GCE towards these metal ions is in conformity with the band gap of the composite in the presence of various test metal ions. The band gap studies of the composite and various “Composite-Metal Ion” systems were obtained by reflectance as well as by computational methods where results are in close agreement, justifying the observed electrochemical behaviour of the systems. The lowest band gap value of the “Composite-Pb” system may be the reason for the excellent electrochemical response of the Glu-h-ZnO modified GCE towards the detection of Pb(II) ion.

This paper focuses on the design and development of a reconfigurable three-degree-of-freedom articulated robot for conducting pick-and-place tasks. To implement the system, an Android platform for the manual control of an articulated robot using wireless Bluetooth technology was developed. This application allows the user to manually reconfigure the robot following the requirements of the integrated system via a user-friendly display. The articulated robot comprises four motors, three of which are used for positioning and orientation and finally used to carry out the pick-and-place task. An Arduino Un R3 board is used to control the movement of the links via a pulse width modulation method. We introduce a set of conveniently composed kinematic and dynamic mathematical models for positioning the robot’s arms and, in our results and discussion section, calculate and report the torque required to move each joint.

A flotel is often used to house personnel and equipment for on-site maintenance of ageing FPSOs. Although tankers are designed to be dry-docked, operating FPSOs (which may be reconverted tankers) must be maintained in the field. The advantage to industry of on-site maintenance and inspection rather than dry-docking of FPSOs is crucial to cost-effectiveness. For multibody systems like FPSO and flotel in a side-by-side configuration, one of the primary questions is the time for which the gangway can remain safely connected between the two bodies. Operators always seek for a maximum possible uptime to operate the gangway, so that FPSO maintenance works are not halted for long durations during the harsh environments. The main factors limiting the operation of a gangway are its extension and rotation due to the relative motions between FPSO and flotel. Therefore, it is firstly important to accurately predict the hydrodynamic interaction between the two bodies for estimating their motions. In the present work, the variation of current drag on the flotel due to the presence of a turret-moored FPSO is investigated. The current drag variation on the flotel is studied by modelling the multibody system in OpenFOAM. Steady state simulations are performed using simpleFoam algorithm to compute the hydrodynamic coefficients of pontoons and columns. SimpleFoam is a steady-state solver for incompressible, turbulent flow, using the SIMPLE (Semi-Implicit Method for Pressure Linked Equations) algorithm. The meshes for FPSO, flotel and fluid domain are created in ICEM-CFD and imported into OpenFOAM. A mesh convergence study is conducted. The simulations are performed for various current velocities and directions in combination with different drafts of FSPO. Finally, a lookup table comprising of current drag coefficients for several cases is prepared for future reference in designing the flotel. A non-collinear environment is the worst scenario for turret-moored FPSO. In most cases, the wind-driven current direction is within ±45° relative to the wave heading. The drag load experienced by the flotel on the columns and pontoons varies as a function of the current direction, the draft and the heading of FPSO relative to the flotel and the location of the flotel (upstream or downstream of FPSO). As FPSO changes yaw angle, the flotel experiences current loads which sometimes vary abruptly due to the shielding effects. The paper presents novel results and explains how the hydrodynamic interactions affect the important current loads experienced by the flotel under various scenarios. The choice of orientation of the flotel relative to FPSO (pontoons parallel or perpendicular to FPSO) is influenced by and must be decided by considering the effect on the current loads. The effects of varying shielding need to be considered by the dynamic positioning system in order to develop robust control methods to maximize uptime for a given installed thruster power. Several studies have been performed to investigate the hydrodynamic interaction between two bodies like cylinders, square columns, rectangular structures, etc. However, very little work has been on the hydrodynamic interaction between FPSO and flotel (semi-submersible platform), especially when this multibody system is subjected to current forces. The present study aims to fill this gap and aid the industry in the preliminary design and configuration of the flotel.

The structural, electronic and optical properties of rare-earth, scandium-based compounds within the family of RE5-T2-In4 (T = Ni, Pd, Pt) intermetallics are calculated by using density functional theory-based orthogonalized linear combination of atomic orbitals method. The studied compounds crystallize in orthorhombic structure with space group Pbam (No. 55). The electronic properties exhibit conducting features of all three compounds. Charge transfer and crystal strength analysis were carried out by computing bond order and effective charge. Regarding optical properties the complex dielectric function, optical conductivity and electron energy loss function have been assessed. All the three compounds demonstrate optically anisotropic behaviour for energy values up to 7.0 eV and turned towards isotropic nature at higher energy (>7.0 eV). Optical conductivity spectra designate that the compounds are optically active for visible to UV light. Two major peaks are observed in energy loss spectra, at 13.2 and 32.6 eV, which correspond to plasmonic resonance points. The interatomic bonding characteristics between distinct pair of atoms within each compound have also been elaborated in comprehensive manner.

Climate change has a large influence on plant functional and phenotypic traits including plant primary and secondary metabolites. One well-established approach to investigating the variation in plant metabolites involves studying plant populations along elevation and latitude gradients. We considered how two space-for-time climate change gradients (elevation and latitude) influence carbohydrate reserves (soluble sugars, starches) and secondary metabolites (monoterpenes, diterpene resin acids) of lodgepole pine trees in western Canada. We were particularly interested in the relationship of terpenes and carbohydrates with a wide range of tree, site, and climatic factors. We found that only elevation had a strong influence on the expression of both terpenes and carbohydrates of trees. Specifically, as elevation increased, concentrations of monoterpenes and diterpenes generally increased and soluble sugars (glucose, sucrose, total sugars) decreased. In contrast, latitude had no impact on either of terpenes or carbohydrates. Furthermore, we found a positive relationship between concentrations of starch and total terpenes and diterpenes in the elevation study; whereas neither starches nor sugars were correlated to terpenes in the latitude study. Similarly, both terpenes and carbohydrates had a much greater number of significant correlations to site characteristics such as slope, basal area index, and sand basal area, in the elevational than in the latitude study. Overall, these results support the conclusion that both biotic and abiotic factors likely drive the patterns of primary and secondary metabolite profiles of lodgepole pine along geographical gradients. Also, presence of a positive relationship between terpenes and starches suggests an interaction between primary ad secondary metabolites of lodgepole pine trees.

Ca-bentonite (CB) alone and in a mixture with limestone (L), tobacco biochar (TB) and zeolite (Z) on the fixation, geochemical fractions and absorption of Cd and Zn by Chinese cabbage in smelter heavily polluted (S-HP) and smelter low polluted (S-LP) soils were investigated. The results showed that the CB + TB and CB + L + TB treatments significantly immobilized Cd up to 22.0% and 29.7%, respectively, and reduced uptake by Chinese cabbage shoot to 36.0% with CB + Z + L and 61.3% with CB + L in S-HP and S-LP soils compared with the control. The CB + Z + L + TB treatment mobilized Cd up to 4.4% and increased absorption in the shoot by 9.9% in S-HP soil. The greatest immobilization of Zn was 53.2% and 58.2% with the CB + Z + L + TB treatment, which reduced Zn uptake in the plant shoot by 10.0% with CB + L and 58.0% with CB + Z + L + TB in S-HP and S-LP soils. The CB + Z + TB and CB + TB treatments mobilized Zn up to 35.4% and 4.9%, respectively, in both soils. Furthermore, the uptake of Zn in plant shoot was observed by 59.0% and 7.9% with application of CB + Z and CB + TB treatments, respectively, in S-HP and S-LP soils. Overall, our results suggest that Ca-bentonite alone and in mixtures with different amendments can be used to reduce the phyto-extraction of Cd and Zn in Zn-smelter polluted soils.

This paper reports results on the structural stability, mechanical, electronic and magnetic behaviour of quaternary ScNiCrX (X = Al, Ga) Heusler alloys under pressure. First principles approach is applied to calculate the structural, mechanical, electronic and magnetic properties of ScNiCrX alloys under pressure. In ferromagnetic phase, both alloys (in Type-γ configuration) are stable. Over a wide pressure range, the calculations of cubic elastic constants (Cij) for both alloys fulfill the necessary criteria for structural stability. Under pressure up to 6.0 GPa, the ScNiCrAl alloy shows half-metallic ferromagnetic behaviour. The ScNiCrGa alloy exhibits half-metallic behaviour over a wide range of pressure (up to 16.0 GPa) as compared to ScNiCrAl alloy. For ScNiCrAl alloy, the spin ↓ energy band gap (Eg) increases (0.27–0.43 eV) with increase in pressure (0.0–6.0 GPa) while for ScNiCrGa alloy Eg increases from 0.30 to 0.58 eV with increase in pressure from 0.0 to 16.0 GPa. For pressure up to 10.0 GPa, the calculated total magnetic moment, MT (for both alloys) exhibit Slater-Pauling rule, MT = (NV – 18) μB. Up to 6.0 GPa, it is expected for ScNiCrAl alloy to show 100% spin-polarization (at Fermi-level, EF) while for ScNiCrGa alloy, 100% spin-polarization is possible to achieve for pressure up to 16.0 GPa. On the basis of results, it is suggested that the ScNiCrX Heusler alloys could be suitable candidates for spintronic devices to operate under harsh environment.

A systematic investigation on structural, electronic, elastic, mechanical and optical properties of novel 1:1 stoichiometric rare-earth $$\mathrm{HoX}\ (\mathrm{X}=\text {Pd, Ag and Cd})$$ intermetallic compounds has been made via ab-initio density functional theory-based linearized augmented plane wave method as coded in wien2k. An outline of local density approximation and generalized gradient approximation have been employed. Structural optimization established the stable CsCl-type cubic structure of $$\mathrm{HoX}\ (\mathrm{X}=\mathrm{Pd, Ag and Cd})$$ compounds. The determined crystal structure stability, compressibility and fracture strength of compounds are enhanced with X in the order $$\mathrm{HoPd}>\mathrm{HoAg}>\mathrm{HoCd}$$ . The interlacing electron dispersion curves at Fermi-level in band structure and density of states substantiate the metallic nature of compounds. The splitting gap between the lower and upper valence bands monotonously becomes narrower with the substitution of heavier core-element $$(\hbox {Pd}\rightarrow \hbox {Ag}\rightarrow \hbox {Cd})$$ . The mechanical constants i.e., bulk modulus (B), Young’s modulus (E), shear modulus ( $${G}_{\mathrm{H}}$$ ), Pugh’s ratio $$(B/G_{\mathrm{H}})$$ , Poisson’s ratio (v) and anisotropic factor (A) have been calculated to corroborate the mechanical properties of compounds. The cationic nature of Ho-atoms and anionic nature of X-atoms has been evaluated through the effective charge $$(\textit{Q}^{*}$$ ) computations. The observed peaks in the low energy region of optical conductivity spectra attribute the intra-band, while the high energy structures are associated with inter-band transitions in $$\mathrm{HoX}\ (\mathrm{X}=\text {Pd, Ag and Cd})$$ compounds. The bond order calculations demonstrate the highest strength of HoCd compound among the herein studied compounds.

A greenhouse pot trial was conducted to investigate the effect of organic amendments combined with triple superphosphate on the bioavailability of heavy metals (HMs), Amorpha fruticosa growth and metal uptake from Pb-Zn mine tailings. Cattle manure compost (CMC), spent mushroom compost (SMC) and agricultural field soil (AFS) were applied to tailings at 5%, 10%, 20% and 30% w/w ratio, whereas sewage sludge (SS) and wood biochar (WB) were mixed at 2.5%, 5%, 10% and 20% w/w ratio. Triple superphosphate (TSP) was added to all the treatments at 4:1 (molar ratio). Amendments efficiently decreased DTPA-extracted Pb, Zn, Cd and Cu in treatments. Chlorophyll contents and shoot and root dry biomass significantly (p&lt, 0.05) increased in the treatments of CMC (except T4 for chlorophyll b) and SMC, whereas treatments of SS (except T1 for chlorophyll a and b), WB and AFS (except T4 for chlorophyll a and b) did not show positive effects as compared to CK1. Bioconcentration factor (BCF) and translocation factor (TF) values in plant tissues were below 1 for most treatments. In amended treatments, soluble protein content increased, phenylalanine ammonialyase (PAL) and polyphenol oxidase (PPO) decreased, and catalase (CAT) activity showed varied results as compared to CK1 and CK2. Results suggested that A. fruticosa can be a potential metal phytostabilizer and use of CMC or SMC in combination with TSP are more effective than other combinations for the in situ stabilization of Pb-Zn mine tailings.

Pollution due to heavy metals is currently a serious problems affecting water bodies. The removal of heavy metals is of great concern due to their toxicity at trace levels and accumulation in the biosystem. Here we review the technical feasibility of biosorption and ion exchange methods for the removal of various heavy metals from the aqueous media. Chemical pretreatment of low-cost biosorbents are presented. Chemically modified biosorbents exhibit far better adsorption capacities than unmodified ones. We also highlighted the effect of pH on the biosorption for maximal uptake of heavy metals, because pH modifies the surface charge of the biosorbent as well as the speciation of heavy metals.

A series of BiFe1-xHf(3/4)xO3 ( 0%, 5%, 10%, 15% and 20%) nanoparticles were synthesized by simple auto combustion technique using citric acid as a fuel. Thermogravimetric (TGA), differential thermogravimetric (DTA), structural, magnetic, dielectric and ferroelectric analyses were investigated. Thermogravimetric analysis provides information of temperature at which phase develops (600 °C). DTA predicts ferroelectric to paraelectric transformation temperature which is found to be 822 °C. X-ray diffraction (XRD) results confirm formation of distorted rhombohedral structure for all compositions along with few traces of Bi25FeO40. The tolerance factor is increased from 0.845 to 0.853 due to larger ionic radius of Hf4+ substitution on Fe site. Crystallite size (D) is found in the range of 24.2–30.48 nm. Saturation magnetization (Ms) is increased to 16 times and remanent magnetization (Mr) is increased to 8 times than that of pure BiFeO3. This increment in magnetic parameters is due to reduction of oxygen vacancies, small crystalline size (less than 62 nm), structural distortion and unbalancing condition for antiferromagnetic magnetic moments of Fe3+ ions. Dielectric parameters depict decrement behavior with increasing of applied field up to 3 GHz. For Fe1-xHf(3/4)xO3, lower value of dielectric permittivity for all compositions is due to reduction of polarization and less growth of grains but more growth of grain boundaries because of mismatching of Hf and Fe3+ ions. P-E hysteresis loop changes from round shape to elliptical shape and it confirms less lossy nature of ferroelectric loops. Higher values of Ms as well as Mr but lower values of dielectric constant as well as remanent polarization for these nanoparticles make them useful for MeRAM (magnetoelectric random access memory) and high resonant applications.

The ground state structural, electronic and optical properties of B1-XInXP (X = 0.0, 0.25, 0.5, 0.75, 1.0) phases have been scrutinized with zinc-blend structure. The full potential linear augmented plane wave method is applied in the framework of density functional theory employing wien2k package. The electronic structure calculations are treated with superior modified-Becke-Johnson potential along with Perdew-Burke-Ernzerhof generalized gradient approximation scheme to harvest the precise energy band gaps in order to get close to experimental outcomes. The computations on ground state structural properties such as volume optimization, equilibrium lattice constants, total equilibrium energy, bulk modulus, compressibility and electronic properties density of states, band structure, energy band gap and in optical properties such as dielectric constant, absorption coefficient, refractive index, electron energy loss function, sum rule, optical reflectivity have been established. The calculated structural, electronic and optical parameters are in excellent agreement with (if) previously reported theoretical and experimental work. The comparative study entailed that mBJ-approach is in strong recommendation for the band gap treatment of materials as it investigates the most close comparable outcomes with the experimental results.

Photoacoustic imaging has been a focus of research for clinical applications owing to its ability for deep visualization with optical absorption contrast. However, there are various technical challenges remaining for this technique to find its place in clinics. One of the challenges is the occurrence of reflection artifacts. The reflection artifacts may lead to image misinterpretation. Here we propose a new method using multiple wavelengths for identifying and removing the reflection artifacts. By imaging the sample with multiple wavelengths, the spectral response of the features in the photoacoustic image is obtained. We assume that the spectral response of the reflection artifact is better correlated with the proper image feature of its corresponding absorber than with other features in the image. Based on this, the reflection artifacts can be identified and removed. Here, we experimentally demonstrated the potential of this method for real-time identification and correction of reflection artifacts in photoacoustic images in phantoms as well as in vivo using a handheld photoacoustic imaging probe.

Effect of Mg-Sr substitution on thermal, structural, spectral, dielectric and magnetic properties were explored in the X-type hexagonal ferrites having composition of Ba2-xMgxCo2-ySry Fe28O46 (x = y = 0, 0.1, 0.2, 0.3, 0.4, 0.5) synthesized via a sol-gel auto-combustion process. The sintered material was characterized by differential scanning calorimetry (DSC), X-ray diffraction (XRD), fourier transform infrared spectroscopy (FTIR), dielectric measurement and vibrating sample magnetometer (VSM) techniques. The sintering temperature necessary for the entire degradation of nitrates and the hexagonal phase development was found 1250 °C which was determined from thermo-gravimetric analysis. The formation of the single phase hexagonal was confirmed from XRD patterns. The lattice constants and cell volume were found to be decreased. This decreased was attributed to the lower ionic size of the substituted metal ions. The porosity of the synthesized material was found to be decreased from 0.463 to 0.417 with the increase in the substitution. FTIR spectroscopy of Mg-Sr doped material revealed the characteristics absorption bands of hexa-ferrites and it was investigated in the frequency range of 400–1000 cm−1. The dielectric measurement has been explored as the function of frequency and composition. Ac conductivity was found to be increased from 1.46 to 2.029 Ω cm−1. The Cole-Cole graphs of prepared materials revealed the promising role of grain boundaries in the conduction mechanism. The improvement in the coercivity was observed with the increase in the Mg-Sr cations, while the saturation magnetization was decreased with the increase in the substitution. The higher value of the coercivity of these synthesized material proposed their use in longitudinal recording media.

Water touches most segments of the petroleum industry and thus cost-effective water management is a key part of oil & gas industry operations. The water to be managed is either co-produced with the hydrocarbons, generated as a by-product from oil/gas processing, and/or utilized to support production operations. While a majority of the water usually receives basic treatment, there are multiple recent drivers for advanced treatment that should facilitate beneficial water reuse. Hence, a toolbox of advanced technologies needs to be considered to ensure that fit for purpose treatment is deployed. Membrane processes are key components of the technology toolbox since they include some of the best available technologies. This paper provides an overview of the various case studies from ConocoPhillips global projects portfolio, which covered various operations such as gas fields, oil fields, oil sands & shale plays. In these case studies, a wide spectrum of membrane processes, including membrane bioreactors, reverse osmosis, microfiltration, ultrafiltration, nanofiltration, ceramic membranes, forward osmosis, membrane distillation, pressure retarded osmosis, membrane contactors, and/or new innovative membrane materials were either installed at full scale capacity, evaluated via field/lab testing, or investigated through desktop studies. The information presented demonstrates that reverse osmosis and nanofiltration are widely utilized by the industry for water desalination and desulfating, respectively. In addition, membrane filtration and bioreactors are frequently applied as standalone treatments for inorganics and organics removal, respectively; or as pretreatment to desalination membranes. Novel membrane technologies and materials are also being developed by the industry for niche applications.

Background and objectives: health care Providers (HCPs) are epicenters for counseling the smokers to quit smoking and adopt healthy lifestyle based on informed decisions. The effects of smoking status of HCPs on cessation practices are contradictory in published literature. The northern Saudi Arabia has high smoking prevalence so is the need for cessation interventions. We carried out the KAP study to determine the difference in knowledge, attitude and practices between smoker and non-smoker HCPs. Materials and Methods: using non-probability consecutive sampling, 268 HCPs including physicians, dentists, pharmacists, nurses, and paramedical staff were included from governmental Hospitals and primary health centers of Aljouf region. A self-administered questionnaire containing Global Adult Tobacco Survey and standard practice guidelines for smoking cessation intervention in Hospitals and primary care centers was used for data collection. Results: we found that HCPs (14.92%) were current smokers, 2.6% were former smokers. Among female HCPs, there was no reported active smoking but 48.94% reported passive smoking. Knowledge of hazards of smoking among HCPs was up to standard. In addition, there was obvious misbelieve that Certain Types of Cigarettes Can Be Less Harmful Than Other among all HCPs (Smokers and non-smoker HCPs significantly differed in advising smoking cessation (p value < 0.01). Among other variables, increasing taxes on tobacco sale (p value < 0.01) and applying standard guidelines for smoking cessation intervention (p value < 0.01) were significantly different between groups. Lacking skills and facilities e.g. medical supply were the most frequency reasons for not starting smoking cessation intervention. Conclusion: because of high prevalence of smoking among HCPs and its negative effects on patient counseling, we suggested that there should be systematic and quality mechanism intact for quitting smoking independent of personal attitude of health care providers and initiate training center along with providing pharmacological supply for smoking cessation intervention in Aljouf region.

Ion exchange is widely used for the removal of selected ions from water streams. Within oil & gas, one application is boiler feedwater treatment to remove hardness, i.e. calcium and magnesium. Weak acid cation (WAC) resins are typically used and advances in material science, polymer chemistry and manufacturing methods have resulted in new resins being introduced to the market. These new resins can lower operating costs through higher capacity, reduced chemical consumption during regeneration or improved physical properties. In this research, the performance of a WAC resin used for boiler feedwater treatment in oil & gas operations (resin A) was compared with two new commercial resins (resins B & C). The results indicated that resin B had the highest operational capacity in comparison to A & C. During regeneration, resin B was the most efficient with 0.43 meq of calcium and magnesium removed from the feed per meq of HCl consumed during regeneration, slightly higher than resins A & C at 0.38 and 0.30 meq/meq respectively. All three resins demonstrated preferential affinity for calcium over magnesium. As breakthrough approached, previously adsorbed magnesium ions were released back to the water resulting in a spike in effluent magnesium that was ≈3× higher than in the feed stream. In full-scale systems, breakthrough can be determined by measuring only the effluent magnesium concentration which can be more sensitive parameter than total hardness and/or calcium.

Syzygium cumini L. (Myrtaceae) is an evergreen medicinal tree confined to tropical and subtropical regions of the world and is mainly recognized for healing of type, two diabetes. An efficient indirect regeneration system has been standardized for this tree using cotyledonary node, inter-node, nodal and leaf segment explants excised from 10 days old aseptic seedling. For callus induction explants were incubated on Murashige and Skoog (1962) medium supplemented with different concentrations of 2, 4-Dichlorophenoxy acetic acid (2, 4-D) or 2, 4, 5-Trichloro phenoxy acetic acid (2, 4, 5-T). All the tested concentrations facilitated callus initiation with different types and varying regeneration potentialities. The regenerated callus on different treatments showed variation in color and texture and best callogenesis (75%) was observed on (7.5 µM) 2, 4-D after 4 weeks. Different morphogenic response was observed when callus was transferred to a secondary organogenic medium fortified with (5.0 µM) benzyl adenine or Kinetin. The yellow white friable (YWF) callus obtained from CN explants exhibited appearance of small leafy structures on secondary medium. Not all types of calli originating from various types of explant were organogenic. Best shoot induction (93%) were observed in (YWF) type of callus obtained from CN explants on MS medium enriched with 5.0 µM BA + 0.25 µM NAA + 10 mg/l AgNO3 with maximum mean shoot number (10.19 ± 0.05) and mean length (4.12 ± 0.32 cm) per clump after 4 weeks of transfer. However the shoot number got increased up to 48 shoots/clump on subsequent subculturing after 12 weeks. For ex vitro rooting shoot lets (4 cm) were excised and pulse treated in full or half strength MS medium augmented with varied concentrations of IBA. Best rhizogenesis (80%) was achieved on 200 µM IBA treated shootlets after 4 weeks of transfer to sterilized soilrite. The regenerants were successfully acclimatized and established in earthen pots with 90% survival.

This paper reports results from the study of the electronic structure, bonding and optical properties of ternary (HfC) m Al 4 C 3 (m = 1, 2, 3) carbides. The interatomic bonding and bond order is studied to elucidate the role to atoms in the structure. The band structures of all three (HfAl 4 C 4 , Hf 2 Al 4 C 5 and Hf 3 Al 4 C 6 ) carbides show conducting nature. All three carbides exhibit direct band gap. Density of states (DOS) spectra of HfAl 4 C 4 , Hf 2 Al 4 C 5 and Hf 3 Al 4 C 6 carbides reveal that the total number of states, N( E F ) at Fermi level are 2.84, 6.51 and 6.37 states/eV, respectively. The electronic charge transfer from Hf and Al atomic sites to C atomic site has been found in all three carbides. The bond order (BO) calculation of these carbides shows the dominating role of Al-C bonds in to the cohesion of crystal structures. Localization index (LI) calculation reflects highly delocalized states near the Fermi level. The dependence of dielectric function and optical conductivity on photon energy show anisotropic behavior of HfAl 4 C 4 , Hf 2 Al 4 C 5 and Hf 3 Al 4 C 6 carbides.

In the present study, the impact of holmium (Ho) substitution on structural, spectral, dielectric and magnetic behavior of Li1.2Zn0.4HoxFe2−xO4 (0.00 ≤ x ≤ 0.15) ferrites was investigated. The development of spinel phase and structural changes induced by Ho doping were confirmed by X-ray diffraction. The accommodation of Ho ions into spinel lattice was restricted for x ≥ 0.06 as indicated by ortho phase (HoFeO3) traces. The decrease in lattice parameter (a) was attributed to the segregation of Ho ions on grain boundaries. FTIR spectra featured two intrinsic vibrational bands v1 (617 cm−1) and v2 (488 cm−1) for x = 0 due to tetrahedral and octahedral vibrations respectively. The compositional dependence of force constants and bond lengths has explained on the basis of cations distribution and oxygen-cation bond distances of respective sites. The addition of Ho ions decreased the saturation magnetization and optimized the coercivity from 59 to 335 Oe, proposing these ferrites for magnetic recording media. Dielectric results for the entire range of frequency (1 MHz to 3 GHz) revealed that ac conductivity increased from 3.5 × 105 to 1.8 × 106 (Ω-cm)−1 up to x = 0.09 and then it decreased slightly for x = 0.12. The effective contribution of grain-interior mechanism to dielectric behavior was confirmed by complex impedance study. The results of dielectric studies displayed that Ho doped lithium ferrites are suitable low loss potential materials for high frequency based applications.

The utilization of low cost, lightweight and high heat resistant composite materials is capturing more and more interest from advanced manufacturing industries. These industries are focusing on new...

In this current study, sawdust and zero-valent iron (Fe0) were used as co-electron donors to evaluate the effects of coexistent ions on the combined heterotrophic and autotrophic denitrification (HAD) processes. The results showed that HCO3- and SO42- drastically enhanced nitrate removal. The promotion effect derived from both biological and chemical process by HCO3- and chemical process by SO42-. However, Ca2+ ions would remarkably increase nitrate removal due to promoting the electron transfer and the metabolic activities of bacteria, whereas the Cu2+ ions inhibited the biological process due to the deleterious effect on bacteria. Meanwhile, Fe2+ and Fe3+ ions exhibited inhibition effect firstly because of their toxicity to bacteria and promotion subsequently due to their enhancement on Fe0 chemical denitrification. Moreover, byproducts such as nitrite, ammonium, dissolved organic carbon (DOC), etc. were also influenced by common ions.

The structural, electronic and optical properties of the ternary carbides Hf 2 Al 3 C 4 and Hf 3 Al 3 C 5 are studied via first principles orthogonalized linear combination of atomic orbitals (OLCAO) method. Results on crystal structure, interatomic bonding, band structure, total and partial density of states (DOS), localization index (LI), effective charge ( Q *), bond order (BO), dielectric function (e), optical conductivity (σ) and electron energy loss function are presented and discussed in detail. The band structure plots show the conducting nature of Hf 2 Al 3 C 4 and Hf 3 Al 3 C 5 carbides. DOS results disclose that the total number of states at Fermi level N( E F ) are 1.89 and 2.38 states/(eV unit cell) for Hf 2 Al 3 C 4 and Hf 3 Al 3 C 5 respectively. The Q * calculations show an average charge transfer of 0.723 and 0.711 electrons from Hf and 0.809 and 0.807 electrons from Al to C sites in Hf 2 Al 3 C 4 and Hf 3 Al 3 C 5 respectively. The BO results provide the dominating role of Al–C bonds with BO value of 6.62 (BO% = 59%) and 6.66 (BO% = 49%) for Hf 2 Al 3 C 4 and Hf 3 Al 3 C 5 respectively and are considered responsible for the crystals cohesion. The LI results reflect the presence of highly delocalized states in the vicinity of the Fermi level. The dielectric function plots of the real (ɛ 1 (ℏω)) and imaginary (ɛ 2 (ℏω)) parts show the anisotropic behavior of Hf 2 Al 3 C 4 and Hf 3 Al 3 C 5 . The results on optical conductivity (σ) support the trends observed in dielectric functions. The electron energy loss functions reveal the presence of sharp peaks both in ab-plane and along c -axis around 20 eV in Hf 2 Al 3 C 4 and Hf 3 Al 3 C 5 ternary carbides.