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The first example of a metalloligand(ML)-based non-interpenetrated SIFSIX MOF [Cu(ML)2(SiF6)]n (ML = Cu(pyac)2 = bis[3-(4-pyridyl)pentane-2,4-dionato]copper(II)) exhibits one-dimensional pore channels decorated with accessible Cu2+ sites that provide superior water vapor stability and CO2 selectivity over CH4vs. similar materials constructed from non-metal containing organic ligands.

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Undoped and nickel-doped zinc oxide thin films were deposited on sodalime glass substrates by utilizing dip coating and ultrasonic spray pyrolysis deposition techniques. In both cases zinc acetate and nickel acetylacetonate were used as zinc precursor and nickel dopant source, respectively. XRD analysis confirms the ZnO wurtzite structure with (002) as the preferential orientation.SEM studies show the formation of two types of morphologies, primarily a porous spherical grains with a grain size distribution from 40 to 150 nm and another, rose-like structures with size distribution from 30 to 200 nm, based on different deposition techniques utilized. The elemental depth profiles across the films were investigated by the secondary-ion mass spectrometry (SIMS). Different gas sensing responses of all ZnO films were obtained for both propane and carbon monoxide gases, at different gas concentrations and operating temperatures. The highest sensing response (~6) for undoped ZnO films was obtained for films deposited by ultrasonic spray pyrolysis (USP). Nevertheless, the highest sensing response (~4 × 104) for doped ZnO films was obtained for films deposited by dip coating method. The behavior of sensing responses is explained in detail based on the morphological properties and the amount of Ni impurities incorporated into the crystal lattice.

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A small flip-angle pulse direct polarization is the simplest method commonly used to quantify various compositions in many materials applications. This method sacrifices the sensitivity per scan in exchange for rapid repeating of data acquisition for signal accumulation. In addition, the resulting spectrum often encounters artifacts from background signals from probe components and/or from acoustic rings leading to a distorted baseline, especially in low-γ nuclei and wideline NMR. In this work, a multi-acquisition scheme is proposed to boost the sensitivity per scan and at the same time effectively suppress these artifacts. Here, an adiabatic inversion pulse is first applied in order to bring the magnetization from the +z to -z axis and then a small flip-angle pulse excitation is used before the data acquisition. Right after the first acquisition, the adiabatic inversion pulse is applied again to flip the magnetization back to the +z axis. The second data acquisition takes place after another small flip-angle pulse excitation. The difference between the two consecutive acquisitions cancels out any artifacts, while the wanted signals are accumulated. This acquisition process can be repeated many times before going into next scan. Therefore, by acquiring the signals multiple times in a single scan the sensitivity is improved. A mixture sample of flufenamic acid and 3,5-difluorobenzoic acid and a titanium silicate sample have been used to demonstrate the advantages of this newly proposed method.

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Predicting adsorption of organic pollutants onto carbon nanomaterials (CNMs) and understanding the adsorption mechanisms are of great importance to assess the environmental behavior and ecological risks of organic pollutants and CNMs. By means of density functional theory (DFT) computations, we investigated the adsorption of 38 organic molecules (aliphatic hydrocarbons, benzene and its derivatives, and polycyclic aromatic hydrocarbons) onto pristine graphene in both gaseous and aqueous phases. Polyparameter linear free energy relationships (pp-LFERs) were developed, which can be employed to predict adsorption energies of aliphatic and aromatic hydrocarbons on graphene. Based on the pp-LFERs, contributions of different interactions to the overall adsorption were estimated. As suggested by the pp-LFERs, the gaseous adsorption energies are mainly governed by dispersion and electrostatic interactions, while the aqueous adsorption energies are mainly determined by dispersion and hydrophobic interactions. It was also revealed that curvature of single-walled carbon nanotubes (SWNTs) exhibits more significant effects than the electronic properties (metallic or semiconducting) on gaseous adsorption energies, and graphene has stronger adsorption abilities than SWNTs. The developed models may pave a promising way for predicting adsorption of environmental chemicals onto CNMs with in silico techniques.

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Aiming to elucidate guest-induced structural changes in the coordination polymer CPL-2, grand canonical Monte Carlo (GCMC) simulations were used to predict CO2 loadings in this material, and the results were compared with experimental isotherms. Our calculations suggest that CPL-2 exhibits more pronounced CO2-induced structural changes than previously reported. As the initial evidence, the isotherm simulated in the previously reported CPL-2 structure (experimentally resolved from X-ray diffraction in the "as-synthesized" CPL-2) underestimated the measured CO2 loadings at high pressure, indicating that CPL-2 might undergo structural changes that enable higher pore volumes at high pressure. GCMC simulations in CPL-2 structures considering moderate unit cell expansions reported in the literature still underestimated high-pressure experimental loadings. However, considering an incremental rotation of the CPL-2 bipyridyl pillars with increasing CO2 pressure, we were able to trace the measured isotherm with the simulation data. Computational analysis shows that ligand rotation in CPL-2 enables higher pore volumes, which, in turn, accommodate more CO2 as the gas pressure increases. Desorption measurements suggest that hysteresis in the CO2 isotherm of CPL-2 may also be linked to ligand rotation, and the measured adsorption/desorption cycles show that the rotation is reversible. Based on our simulations for CPL-4 and CPL-5 and previously reported experimental data, it is likely that these materials, which differ from CPL-2 in the bipyridyl ligand, behave similarly in the presence of CO2. Our results help understand the behavior of these materials, which present the kind of structural changes that could be potentially exploited to enhance the CO2 working capacity of ultra-microporous materials for carbon capture applications.

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Pure and copper (Cu)-incorporated tin oxide (SnO2) pellet gas sensors with characteristics provoking gas sensitivity were fabricated and used for measuring carbon monoxide (CO) atmospheres. Non-spherical pure SnO2 nano-structures were prepared by using urea as the precipitation agent. The resultant SnO2 powders were ball milled and incorporated with a transition metal, Cu, via chemical synthesis method. The incorporation is confirmed by high-resolution transmission electron microscope (HRTEM) analysis. By utilizing Cu-incorporated SnO2 pellets an increase in the CO sensitivity by an order of three, and a decrease in the response and recovery times by an order of two, were obtained. This improvement in the sensitivity is due to two factors that arise due to Cu incorporation: necks between the microparticles and stacking faults in the grains. These two factors increased the conductivity and oxygen adsorption, respectively, at the pellets' surface of SnO2 which, in turn, raised the CO sensitivity.

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Pillared clay based composites containing transition metals and a surfactant, namely MAlOr-NaBt (Bt=bentonite; Or=surfactant; M=Ni(2+), Cu(2+)or Co(2+)), were prepared to study selectivity and capacity toward single and multiple-component adsorption of bisphenol A (BPA) and 2,4-diclorophenol (DCP) from water. Tests were also performed to account for the presence of natural organic matter in the form of humic acid (HA). Equilibrium adsorption capacities for single components increased as follows: NaBt

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This work presents a novel technique to deposit ZnO thin films through a metal vacuum evaporation technique using colloidal nanoparticles (average size of 30 nm), which were synthesized by our research group, as source. These thin films had a thickness between 45 and 123 nm as measured by profilometry. XRD patterns of the deposited thin films were obtained. According to the HRSEM micrographs worm-shaped nanostructures are observed in samples annealed at 600 °C and this characteristic disappears as the annealing temperature increases. The films obtained were annealed from 25 to 1000 °C, showing a gradual increase in transmittance spectra up to 85%. The optical band gaps obtained for these films are about 3.22 eV. The PL measurement shows an emission in the red and in the violet region and there is a correlation with the annealing process.

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Inspired by the stepwise addition of octanuclear iron units into mammalian ferritin, a "stop-and-go" synthesis strategy was used to prepare two microporous (Langmuir surface area, 490 m(2) g(-1); effective pore size, 4-5 Å) hierarchical materials {[Fe8(µ4-O)4(µ-pz)12Cl0.3(µ-O)1.85}n () and {[Fe8(µ4-O)4(µ-4-Me-pz)12Cl0.4(µ-O)1.8}n (), which are new members of the EO2 family of polymeric materials (E = C, Si and Ge). The secondary building units (SBUs) E = [Fe8(µ4-O)4(µ-4-R-pz)12] (Fe8) are nanoscale pseudo-spherical clusters, rather than single atoms, forming µ-oxo Fe-O-Fe linkages between Fe8-SBUs. The characteristic Fe-O-Fe asymmetric stretching mode in the infrared (IR) spectra of these compounds appearing at around 800 cm(-1) suggest the formation of approximately linear µ-oxo Fe-O-Fe linkages between Fe8-SBUs in and . We employ the concept of continuous random network (CRN) to describe for the first time the framework features of a Fe8-based amorphous materials, in which the average connecting numbers of each Fe8-cluster are ∼3.7 and ∼3.6 for and , respectively. (57)Fe-Mössbauer spectroscopic analysis provides insights to the intercluster connectivity of and on one hand and to their magnetic properties on the other, evident by a magnetic split sextet below 30 K. The combination of Mössbauer spectroscopy and magnetism measurements reveals a spin-glass behavior with Tg of ∼30 K. The hierarchical porous materials and straddle the gap between metal oxides and metal-organic frameworks (MOFs). This study may open an alternative way for the development of multifunctional materials based on high nuclearity metal clusters.

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Fixed-beds of transition metal (Co(2+), Ni(2+) or Cu(2+)) inorganic-organic pillared clays (IOCs) were prepared to study single- and multi-component non-equilibrium adsorption of a set of pharmaceutical and personal care products (PPCPs: salicylic acid, clofibric acid, carbamazepine and caffeine) from water. Adsorption capacities for single components revealed that the copper(II) IOCs have better affinity toward salicylic and clofibric acid. However, multi-component adsorption tests showed a considerable decrease in adsorption capacity for the acids and an unusual selectivity toward carbamazepine depending on the transition metal. This was attributed to a combination of competition between PPCPs for adsorption sites, adsorbate-adsorbate interactions, and plausible pore blocking caused by carbamazepine. The cobalt(II) IOC bed that was partially calcined to fractionate the surfactant moiety showcased the best selectivity toward caffeine, even during multi-component adsorption. This was due to a combination of a mildly hydrophobic surface and interaction between the PPCP and cobalt(II). In general, the tests suggest that these IOCs may be a potential solution for the removal of PPCPs if employed in a layered-bed configuration, to take care of families of adsorbates in a sequence that would produce sharpened concentration wavefronts.

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The present study focuses on the long-range structural changes that occur in the porous coordination polymer Cu2(pzdc)2(bpy) (pzdc = pyrazine-2,3-dicarboxylate, bpy = 4,4'-bipyridine), also known as CPL-2, upon adsorption of CO2 at 25 °C and up to 7 atm. The structural data were gathered using in situ diffraction studies. CPL-2 exhibited an unexpected hysteretic adsorption-desorption process. The onset of hysteresis occurs at a pressure where full occupancy of the volume of the CPL-2 galleries is achieved while the framework retains a structure similar to what is observed under ambient conditions. Moreover, the onset occurs at a CO2 partial pressure larger than 2 atm and could be related to a combination of adsorbate-adsorbent interactions and forces exerted onto the CPL-2 framework. Pore volumes estimated from fits of the Dubinin-Astakhov isotherm model against the CO2 desorption data gathered at 25 and -78.5 °C, respectively, provided further evidence of the aforementioned CPL-2 framework changes. These findings are of relevance to the understanding of adsorption processes in metal organic frameworks or coordination polymers under conditions that are of relevance to gas capture at industrial scale.

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The physical characteristics of ultrasonically sprayed indium-doped zinc oxide (ZnO:In) thin films, with electrical resistivity as low as 3.42 × 10-3 Ω·cm and high optical transmittance, in the visible range, of 50%-70% is presented. Zinc acetylacetonate and indium chloride were used as the organometallic zinc precursor and the doping source, respectively, achieving ZnO:In thin films with growth rate in the order of 100 nm/min. The effects of both indium concentration and the substrate temperature on the structural, morphological, optical, and electrical characteristics were measured. All the films were polycrystalline, fitting well with hexagonal wurtzite type ZnO. A switching in preferential growth, from (002) to (101) planes for indium doped samples were observed. The surface morphology of the films showed a change from hexagonal slices to triangle shaped grains as the indium concentration increases. Potential applications as transparent conductive electrodes based on the resulting low electrical resistance and high optical transparency of the studied samples are considered.

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Objetivo: Describir los resultados del tratamiento quirúrgico de las fracturas supracondilea de humero en niños en el Hospital Daniel Alcides Carrión. Metodología: Estudio Descriptivo, retrospectivo y transversal. Se incluyó a pacientes operados por medio de reducción cruenta más colocación de clavos y el diagnóstico de fractura supracondilea de humero distal en niños en los años 2010 al 2012 en el Hospital Daniel Alcides Carrión. Se revisó las Historia Clínicas y radiografías. Resultados: Se operaron a 47 niños, con una media de edad de 5.6±2.07, a predominio del sexo masculino en un 72.3 por ciento. En todos los casos la fractura fue provocada por caída a nivel con un 97 por ciento en Extensión como mecanismo de producción. Los resultados funcionales según los criterios de Flynn fue excelente en 19 por ciento, Bueno 58 por ciento, Regular en 19 por ciento y malo en 4 por ciento. Los resultados estéticos según criterios de Flynn fueron excelente en 66 por ciento, Bueno en 38 por ciento, Regular en 2 por ciento y Malo en 2 por ciento. Conclusiones: La reducción cruenta más estabilización con clavijas es un tratamiento válido para las fracturas de humero en niños como opción al no contar con radiografías intra-operatorias o intensificador de imágenes dando buenos resultados funcionales y estéticos.

Objective: To describe the results of surgical treatment of supracondylar fractures of the humerus in children at Hospital Daniel Alcides Carrion. Methods: descriptive study, retrospective and cross. We included patients with reduction and pinning operated with the diagnosis of distal humeral supracondylar fracture in children in the years 2010 to 2012 at the Hospital Daniel Alcides Carrion. We reviewed the history Clinics and radiographs. Results: 47 children were operated, with a mean age of 5.6±2.07, a male predominance in 72.3 per cent. In all cases the fracture was caused by fall and 97 per cent in extension as a mechanism of production. The functional results according to Flynn's criteria were excellent in 19 per cent, Good 58 per cent, Fair in 19 per cent and poor in 4 per cent. The aesthetic results according to Flynn criteria were excellent in 66 per cent, Good 38 per cent, Fair and Poor in 2 per cent. Conclusions: Open reduction and pinning is a valid treatment for fractures of the humerus in children in cases in having no intra-operative X-ray or image intensifier giving good functional and aesthetic results.

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Chromium and ruthenium-doped zinc oxide (ZnO:Cr) and (ZnO:Ru) thin solid films were deposited on soda-lime glass substrates by the sol-gel dip-coating method. A 0.6 M solution of zinc acetate dihydrate dissolved in 2-methoxyethanol and monoethanolamine was used as basic solution. Chromium (III) acetylacetonate and Ruthenium (III) trichloride were used as doping sources. The Ru incorporation and its distribution profile into the films were proved by the SIMS technique. The morphology and structure of the films were studied by SEM microscopy and X-ray diffraction measurements, respectively. The SEM images show porous surfaces covered by small grains with different grain size, depending on the doping element, and the immersions number into the doping solutions. The sensing properties of ZnO:Cr and ZnO:Ru films in a propane (C3H8) atmosphere, as a function of the immersions number in the doping solution, have been studied in the present work. The highest sensitivity values were obtained for films doped from five immersions, 5.8 and 900, for ZnO:Cr and ZnO:Ru films, respectively. In order to evidence the catalytic effect of the chromium (Cr) and ruthenium (Ru), the sensing characteristics of undoped ZnO films are reported as well.

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We obtain simple exact formulas for the refracted wavefronts through plano-convex aspheric lenses with arbitrary aspheric terms by considering an incident plane wavefront propagating along the optical axis. We provide formulas for the zero-distance phase front using the Huygens' Principle and the Malus-Dupin theorem. Using the fact that they are equivalent, we have in the second method found a way to use an improper integral, instead of the usual evaluated integral, to arrive at these formulas. As expected, when the condition of total internal reflection is satisfied, there is no contribution to the formation of the refracted wavefront.

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Pharmaceutical and Personal Care Products (PPCPs) are considered emerging contaminants, and their efficient removal from water is going to be a challenging endeavor. Microporous adsorbent materials, including pillared clays, could offer a potential solution if tailored properly. Although pillared clays have been employed previously for the removal of organics, the effective removal of PPCPs will only be possible if their surface and textural properties are manipulated from the bottom-up. This work presents the use of modified inorganic-organic pillared clays (IOCs) for the adsorption of salicylic acid, clofibric acid, carbamazepine, and caffeine. The IOCs have been modified with Co(2+), Cu(2+), or Ni(2+) to induce complexation-like adsorbate-adsorbent interactions at ambient conditions, in an attempt to provide an efficient and yet reversible driving force in the sub-ppm concentration range. Furthermore, the IOCs were partially calcined to increase effective surface area by an order of magnitude while preserving some hydrophobicity. In general, the Ni(2+) IOCs exhibited the greatest interaction with salicylic and clofibric acids, respectively, while the Co(2+) adsorbents excelled at adsorbing caffeine at low concentrations. All of the metal-modified IOCs showed comparable adsorption capacities for the case of carbamazepine, probably due to the lack of availability of particular functional groups in this adsorbate.

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In situ high temperature X-ray diffraction, nitrogen porosimetry and gas adsorption at room temperature were used to elucidate the effect of the degassing or activation temperature on the long-range and micropore textural properties of a series of coordination polymers with pillared-layer structures. Ramp-and-soak thermal gravimetric analysis performed at selected activation temperatures were used to verify the thermal stability of a CPL-n series [Cu(2)(pzdc)(2)L; pzdc = pyrazine-2,3-dicarboxylate; L = 4,4-azopyridine (apy) for CPL-4, 1,2-di-(4-pyridil)-ethylene (bpe) for CPL-5, N-(4-pyridyl)-isonicotinamide (pia) for CPL-6, and 1,2-di-(4-pyridyl)-glycol (dpyg) for CPL-7]. Although the activation temperatures were far below the decomposition point of the complexes, these resulted in significant and unique changes in micropore surface area and volume, even for CPL-4, -5 and -6, which contained pillar ligands with similar dimensions and similar structural long-range order. For the case of CPL-7, however, the framework appeared to be non-porous at any given activation temperature. Pure component equilibrium adsorption data gathered for CO(2), CH(4), and N(2) were used to elucidate the CPL-n materials potential for storage and separations at room temperature. All of the materials exhibited considerable selectivity toward CO(2), particularly at moderate pressures. Meanwhile, CO(2) isosteric heats of adsorption indicated that the pore functionalities arising from the pillar ligands provided similar interactions with the adsorbate in the cases of CPL-4 and -5. For CPL-6, the presence of the carbonyl (C[double bond, length as m-dash]O) group appeared to enhance interactions with CO(2) at low loadings.

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Cover crop species represent an affordable and effective weed control method in agroecosystems; nonetheless, the effect of its use on arbuscular mycorrhizal fungi (AMF) has been scantily studied. The goal of this study was to determine root colonization levels and AMF species richness in the rhizosphere of maize plants and weed species growing under different cover crop and weed control regimes in a long-term experiment. The treatment levels used were (1) cover of Mucuna deeringian (Muc), (2) "mulch" of Leucaena leucocephala (Leu), (3) "mulch" of Lysiloma latisiliquum (Lys), (4) herbicide (Her), (5) manual weeding (CD), (6) no weeding (SD), and (7) no maize and no weeding (B). A total of 18 species of AMF belonging to eight genera (Acaulospora, Ambispora, Claroideoglomus, Funneliformis, Glomus, Rhizophagus, Sclerocystis, and Scutellospora) were identified from trap cultures. Muc and Lys treatments had a positive impact on AMF species richness (11 and seven species, respectively), while Leu and B treatments on the other hand gave the lowest richness values (six species each). AMF colonization levels in roots of maize and weeds differed significantly between treatment levels. Overall, the use of cover crop species had a positive impact on AMF species richness as well as on the percentage of root colonized by AMF. These findings have important implications for the management of traditional agroecosystems and show that the use of cover crop species for weed control can result in a more diverse AMF community which should potentially increase crop production in the long run.

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