349 research outputs found

    Photoemission studies of the near Fermi level spectral weight shifts in FeSe1-xTex superconductor

    Full text link
    Our valence band photoelectron spectroscopic studies show a temperature dependent spectral weight transfer near the Fermi level in the Fe-based superconductor FeSe1-xTex. Using theoretical band structure calculations we have shown that the weight transfer is due to the temperature induced changes in the Fe(Se,Te)4 tetrahedra. These structural changes lead to shifts in the electron occupancy from the xz/yz and x2-y2 orbitals to the 3z2-r2 orbitals indicating a temperature induced crossover from a metallic state to an Orbital Selective Mott (OSM) Phase. Our study presents the observation of a temperature induced crossover to a low temperature OSM phase in the family of Fe chalcogenides.Comment: 10 pages, 4 figure

    Productivity, quality and economics of four spring wheat (Triticum aestivum L.) cultivars as affected by three cultivation technologies

    Get PDF
    ArticleManaging farming inputs in wheat production technologies is an issue of paramount importance to attain optimum profitable production. To examine how varying the farming inputs affects the nutrients uptake and productivity of spring wheat (Triticum aestivum L.) cultivars and to determine the economic efficiency of various cultivation technologies, three-year field experiments were laid out at the Russian Research Institute of Agriculture, during the 2015–2017 growing seasons. Experiments were conducted once a year using randomized complete block arranged in a split plot experimental design with three replications, with the cultivation technology treatments (basic, intensive and high intensive technology) as the main plots, and spring wheat cultivars (Zelata, Lubova, Liza and Ester) as the sub-main plots. The highest grain yield (10.8 t ha-1), harvest index (42.9%), gluten content (39.45%) and gluten index (71.17%) observed for spring wheat cultivar Lubova with the moderate application of farming inputs as an intensive cultivation technology. Highest protein content (18.02%) was attained for both intensive and high intensive cultivation technology with the cultivar Lubova, and the highest 1,000 grains weight (46.32 g) was recorded by cultivar Lubova in basic cultivation technology. Applying moderate amount of inputs as an intensive cultivation technology resulted in highest wheat yield and net income

    Productivity of various barley (Hordeum vulgare L.) cultivars under semi-arid conditions in southern Russia

    Get PDF
    ArticleDrought is a significant factor limiting crop production in arid conditions. In the dry climatic weather situation of southern Russia, ten - year laboratory trials and subsequent field experiments were laid out on various barley varieties collected across the globe during 2007 – 2017 period. This study was conducted to ascertain from the collection of barley cultivars of the entire world which one is best suited to stressful climatic conditions by being tolerant to drought, heat and salinity which can be adopted for barley breeding. According to the results obtained, the varieties that are tolerant to dry climatic conditions are as follows: Alga (Lithuania), Brenda, Henni (Germany), Décor (Great Britain), Furat 5 (Syria), Vakula (Ukraine), Ataman (Belarus) and Vladimir (Russia); heat resistant varieties are: Brenda (Germany), Alga (Lithuania), Furat 5 (Syria), Ataman (Belarus) , Vladimir and Ratnik (Russia); Salt - resistant varieties: Alga (Lithuania), Henni (Germany) and Vladimir (Russia). The selected varieties did not show any sign of adverse weather effect resulting in stable grain productivity throughout the entire duration of this research over the years, they had large grain size and stable 1 , 000 grains weight. However, the yield of selected cultivars varied over the years which was about 1.1 – 1.4 t ha - 1

    New trends on microbiological water treatment.

    Get PDF
    Silver nanoparticle-decorated porous polypropylene filter is prepared by physical vapor deposition method using a modified Balzers 760 coating machine. Silver nanoparticles were generated by electron beam bombardment of the silver metal. A 45nm layer of the silver nanoparticles were subsequently deposited on the polypropylene filter homogenously. The nano silver-coated filters were characterized using scanning electron microscopy, transmission electron microscopy and atomic force microscopy. The antibacterial efficiency of the nano silver-coated filters was evaluated using a custom- made experimental set up and the membrane filter method. A zone of inhibition test was also performed to compare the bactericidal effect of coated versus non-coated filters. At a flow rate of 3L/hr, the output count of Escherichia coli was zero after 6.5 hours filtration when the input water had a bacterial load of 103 colony-forming units (cfu) per milliliter. The inductively coupled plasma/mass spectrometry (ICP/MS) results showed that the 45nm layer of the silver nanoparticles are stable on the water filter and are not washed away by water flow even after 6.5h filtration

    Complete removal of pathogenic bacteria from drinking water using nano silver-coated cylindrical polypropylene filters.

    Get PDF
    An attempt was made to investigate the removal of Escherichia coli bacteria from drinking water using nano silver-coated polypropylene water filter. For the production of nano silver filters, a modified Balzers 760 machine equipped with an electron beam gun was used. The nano-silver particles were made by electron beam bombardment of the silver metal, which were subsequently deposited on the polypropylene filters evenly. The thickness of the nano layer coated on the filters was 35.0 nm. The nano silver-coated filters were characterized using scanning electron microscopy, X-ray diffraction, transmission electron microscopy, and atomic force microscopy. The antibacterial efficiency of the filters was evaluated using the membrane filter method. At a flow rate of 3 l/h, the output count of E. coli was zero after 7 h filtration when the input water had a bacterial load of 103 colony-forming units (cfu) per milliliter. The inductively coupled plasma/mass spectrometry (ICP/MS) results showed that the 35 nm layer of the silver nanoparticles were stable on the water filter and were not washed away by water flow even after 72 h

    New trends in microbiological water treatment

    Get PDF
    Clean water is essential to human life as well as the rest of the ecosystem. Nowadays, we are experiencing difficulties in responding to the increasing demand for reliable water sources. There are many approaches available for the disinfection of water. Each method has some practical difficulties and disadvantages. Nanotechnology is an emerging advanced technology with significant potential in various fields including solving water purification problems. Using nanotechnology methods it is possible to convert metal ions into nanoparticles for medical and non-medical [1] applications. The major property that makes nanoparticles attractive is that they are extremely small in size (1-100nm), which provides them with a higher surface area per unit mass. Nanomaterials often show unique and considerably enhanced physical, chemical and biological properties compared to their macro-scaled counterpart

    Chemoinformatic-guided engineering of polyketide synthases

    Get PDF
    Polyketide synthase (PKS) engineering is an attractive method to generate new molecules such as commodity, fine and specialty chemicals. A central challenge in PKS design is replacing a partially reductive module with a fully reductive module through a reductive loop exchange, thereby generating a saturated β-carbon. In this work, we sought to establish an engineering strategy for reductive loop exchanges based on chemoinformatics, a field traditionally used in drug discovery. We first introduced a set of donor reductive loops of diverse genetic origin and chemical substrate structures into the first extension module of the lipomycin PKS (LipPKS1). These results demonstrated that chemical similarity between the substrate of the donor loops and recipient LipPKS1 correlated with product titers. Consequently, we identified donor loops with substrates chemically similar to LipPKS1 for further reductive loop exchanges, and we observed a statistically significant correlation with production. Reductive loops with the highest chemical similarity resulted in production of branched, short-chain fatty acids reaching a titer of 165 mg/L in Streptomyces albus J1074. Collectively, our work formulizes a new chemoinformatic paradigm for de novo PKS biosynthesis which may accelerate the production of valuable bioproducts

    Operative technique and early experience for robotic-assisted laparoscopic nephroureterectomy (RALNU) using da Vinci Xi

    Get PDF
    Purpose: Robotic-assisted laparoscopic nephroureterectomy (RALNU) has been previously utilized for management of upper tract urothelial carcinoma. The da Vinci Xi surgical system was released in April of 2014. We describe our operative technique and early experience for RALNU using the da Vinci Xi system highlighting unique features of this surgical platform. Materials and methods: A total of 10 patients with a diagnosis of upper tract urothelial carcinoma underwent RALNU using the da Vinci Xi system between April and November of 2014. A novel, oblique “in line ” robotic trocar configuration was utilized to access the upper abdomen (nephrectomy portion) and pelvis (bladder cuff excision) without undocking. The port hopping feature of da Vinci Xi was utilized to facilitate optimal, multi-quadrant visualiza-tion during RALNU. Results: Robotic-assisted laparoscopic nephroureterectomy was successfully completed without open conversion in all 10 patients. Mean operative time was 184 min (range 140–300 min), mean estimated blood loss was 121 cc (range 60–300 cc), and mean hospital stay was 2.4 days. Final pathology demonstrated high grade urothelial carcinoma in all patients. Surgical margins were negative in all patients. No intra-operative complications were encountered. One patient developed a pulmonary embolus after being discharged. No patients required a blood transfusion. Mean patient follow-up was 130 days (range 15–210 days). Conclusion: The use of da Vinci Xi with a novel, oblique “in line ” port configuration and camera port hopping tech-nique allows for an efficient and reproducible method for RALNU without the need for repositioning the patient or the robot during surgery
    corecore