Exact Chemical Composition Research Articles

The In Vitro and In Vivo Wound Healing Properties of the Chinese Herbal Medicine “Jinchuang Ointment”

“Jinchuang ointment” is a traditional Chinese herbal medicine complex for treatment of incised wounds. For more than ten years, it has been used at China Medical University Hospital (Taichung, Taiwan) for the treatment of diabetic foot infections and decubitus ulcers. Three different cases are presented in this study. “Jinchuang” ointment is a mixture of natural product complexes from nine different components, making it difficult to analyze its exact chemical compositions. To further characterize the herbal ingredients used in this study, the contents of reference standards present in a subset of the ointment ingredients (dragon's blood, catechu, frankincense, and myrrh) were determined by HPLC. Two in vitro cell based assay platforms, wound healing and tube formation, were used to examine the biological activity of this medicine. Our results show that this herbal medicine possesses strong activities including stimulation of angiogenesis, cell proliferation, and cell migration, which provide the scientific basis for its clinically observed curative effects on nonhealing diabetic wounds.

Density and Young׳s Modulus of ternary glasses close to the eutectic composition in the CaO–Al2O3–SiO2-system

The elastic properties and the density of ternary glass forming systems within the CaO–SiO2–Al2O3-system (CAS) were evaluated. Different glass compositions near the lowest eutectic (1170°C) composition within the CaO–Al2O3–SiO2-system have been melted from pure raw materials. Their target compositions differed not more than 4wt% for each component. Exact chemical compositions were measured by x-ray fluorescence. The density, and acoustic properties were determined and the Young׳s Moduli were derived herefrom. It was of special interest to obtain information on these properties and their dependencies upon small variations in the composition. The density values were between 2.600 and 2.667gcm−3 and the packing density factors Vp of the oxides glasses using the ionic radii of Pauling were in the range from 0.559 to 0.571. The determined data were compared to different model calculations. Density model calculations show relative deviations between 2 and 6%. The values calculated from the model for Young׳s Modulus by Makishima and Mackenzie (1973) [1] were somewhat smaller than the measured ones. The correction by Rocherulle et al. (1989) [3] of the Makishima model showed better agreement with the measured values.

Optical and material analysis of opacified hydrophilic intraocular lenses after explantation: a laboratory study.

BackgroundThe opacification of hydrophilic intraocular lenses (IOLs) is a very rare complication in terms of absolute numbers. We report on the analyses of opacified Euromaxx ALI313Y and ALI313 IOLs (Argonoptics, Germany) using light and scanning electron microscopy, X-ray spectroscopy and optical bench analysis.MethodsOpacified Euromaxx ALI313Y and ALI313 IOLs were explanted after patients presented with a decrease in visual acuity. The explants were sent to our laboratory and examined using light and scanning electron microscopy. The composition of the deposits was analysed using X-ray spectroscopy. The optical quality of the intraocular lens (IOL) was assessed using the OptiSpheric IOL PRO optical bench (Trioptics GmbH Wedel, Germany). Modulation transfer function (MTF) was measured at all spatial frequencies and United States Air Force (USAF) 1951 resolution target pictures were documented.ResultsMacroscopically, the entire optic was opacified in all IOLs. Light and scanning electron microscopy revealed numerous fine, granular, crystalline-like deposits, which were always distributed in a line parallel to the anterior and posterior surfaces of the IOLs. X-ray spectroscopy could prove the deposits consisted of Calcium and Phosphate. Measurements in the optical bench showed deterioration of MTF values at all spatial frequencies and the USAF target pictures demonstrated a significant reduction of brightness as well as resolution with the opacified IOLs.ConclusionsThe calcification of hydrophilic IOLs only occurs rarely. The exact chemical composition of the deposits can be assessed by means of X-ray spectroscopy. Optical quality analysis of the explanted Euromaxx ALI313Y and ALI313 IOLs showed significant reduction of MTF values, which was confirmed by USAF target pictures.

An attempt to determine the chemical composition of reservoir waters from Polish Lower Paleozoic shale formations

The exact chemical composition of reservoir water from Lower Paleozoic shale formations is not known. Reservoir fluids produced during the tests performed in these formations contain a considerable amount of flowback fluid. Taking into consideration the results of the chemical composition monitoring of those fluids we observed a gradual growth of Cl, Na, Ca, Mg, and Br ion contents, approaching characteristic values of Cambrian reservoir water. In addition, the analysis of the hydrochemical indices of the examined liquids indicates the chemical similarity of Ordovician-Silurian waters to Cambrian waters.

A prototype Ultraviolet Light Sensor based on ZnO Nanoparticles/Graphene Oxide Nanocomposite Using Low Temperature Hydrothermal Method

A new prototype UV nanosensor using ZnO nanoparticles (NPs)/graphene oxide (GO) nanocomposite (ZnO-NP/GO) on silicon substrate is reported in this paper. The hybrid nanocomposite structure has been developed by an optimized hydrothermal process at low growth temperature (∼50 °C). In this hybrid nanosensor, the ZnO nanoparticles act as UV- absorbing and charge carrier generating material, while graphene with its superior electrical conductivity has been used as a charge transporting material. Various nanostructure characterization techniques were intensively utilized including SEM, EDX, XRD, FTIR and UV-VIS. Also, the I-V measurement was employed to evaluate the prototype sensor. The morphological SEM analysis showed that the ZnO-NPs (average diameter of 20 nm) were dispersed evenly on the GO sheets. As well, the EDX spectra confirmed the exact chemical composition of the intended structure. The room temperature UV-VIS measurement revealed an enhanced optical absorption of UV-light at an absorption band centered on 375 nm. The improved optical and electrical properties were observed at an optimum relative concentration of 1:10. Under UV light illumination, the measured I-V characteristic of the prototype detector exhibited a considerable photocurrent increase of the ZnO-NP/GO nanocomposite compared to pristine ZnO nanostructure. These results can be promising for future enhanced UV- sensing applications.

Sr1.98Eu0.02SiO4 luminescence whisker based on vapor-phase deposition: Facile synthesis, uniform morphology and enhanced luminescence properties

A high performance strontium silicate phosphor has been successfully synthesized though a facile vapor-phase deposition method. The product consists of single crystal whiskers which are smooth and uniform, and with a sectional equivalent diameter of around 5μm; the aspect ratio is over 50 and no agglomeration can be observed. X-ray diffraction result confirmed that the crystal structure of the whisker was α’-Sr2SiO4. The exact chemical composition was Sr1.98Eu0.02SiO4 which was analyzed by energy dispersive spectrometer and inductively coupled plasma-mass spectrometer. The whisker shows broad green emission with peak at 523nm ranging from 470 to 600nm (excited at 370nm). Compared with traditional Sr2SiO4:Eu phosphor, durability (at 85% humidity and 85°C) and thermal stability of the whisker are obviously improved. Moreover, growth mechanism of the Sr1.98Eu0.02SiO4 whiskers is Vapor–Liquid–Solid. On a macro-scale, the product is still powder which makes it suitable for the current packaging process of WLEDs.

Characteristics and Metallurgical Effects of Medium Basicity Refining Slag on Low Melting Temperature Inclusions

Recently, large sized CaO-Al2 O3 inclusions with low melting temperature have been the main reason for lowering mechanical properties of high strength low alloy (HSLA) steel plates. New philosophy, i. e. refining by top slag with relatively low basicity and Al2 O3 content, was proposed to control such kind of inclusions. Firstly, the characteristics of refining slag, such as component activities and sulphide capacity (Cs) of CaO-A12O3-SiO2-MgO slag, were studied through thermodynamic calculation. Then, slag-metal equilibrium experiments were carried out in laboratory to investigate the exact chemical composition of refining slag together with thermodynamic analysis. Finally, industrial trials were done to verify the desulphurization ability and inclusions control in steel refined by the new slag. Thermodynamic calculations indicated that the slags with basicity of 3. 5 and Al2 O3 content of 20% and basicity of 5.0 and A12O3 content of 20% or 25% have high values of CaO activity, sulphide capacity and ratio of MgO activity to Al2 O3 activity. Laboratory equilibrium experiments showed that the slag with basicity of about 4. 5 and Al2 O3 content of about 20% is helpful for increasing the melting temperature of inclusions in steel. After introducing such kind of refining slag in industrial trials, the sulphur content in eight heats of steel is below 20 × 10−6, which meets the requirement of HSLA steel, and most inclusions distribute in relatively high melting zone (±1773 K) of CaO-Al2O3-MgO(-SiO2) quasi-ternary diagram. New philosophy of top refining slag is feasible to control low melting point inclusions of CaO-Al2O3 system in HSLA steel.

Peptide profiling of Internet-obtained Cerebrolysin using high performance liquid chromatography - electrospray ionization ion trap and ultra high performance liquid chromatography - ion mobility - quadrupole time of flight mass spectrometry.

Cerebrolysin, a parenteral peptide preparation produced by controlled digestion of porcine brain proteins, is an approved nootropic medicine in some countries. However, it is also easily and globally available on the Internet. Nevertheless, until now, its exact chemical composition was unknown. Using high performance liquid chromatography (HPLC) coupled to ion trap and ultra high performance liquid chromatography (UHPLC) coupled to quadrupole-ion mobility-time-of-flight mass spectrometry (Q-IM-TOF MS), combined with UniProt pig protein database search and PEAKS de novo sequencing, we identified 638 unique peptides in an Internet-obtained Cerebrolysin sample. The main components in this sample originate from tubulin alpha- and beta-chain, actin, and myelin basic protein. No fragments of known neurotrophic factors like glial cell-derived neurotrophic factor (GDNF), neurotrophin nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF), and ciliary neurotrophic factor (CNTF) were found, suggesting that the activities reported in the literature are likely the result of new, hitherto unknown cryptic peptides with nootropic properties.

Phase separation in an ionomer glass: Insight from calorimetry and phase transitions

The G338 ionomer glass is a fluoro-alumino-silicate system, which is used as the powder component of glass ionomer cements (GICs) in dental applications. However, despite progress in understanding the nature of this glass, chemical identity of its separated amorphous phases has not yet been conclusively determined. In this work, we identify these phases by performing differential scanning calorimetry (DSC) and X-ray diffraction (XRD) analyses on both the as-received glass and heat-treated samples. We detected three glass transitions in the as-received G338 glass during DSC upscanning, implying the co-existence of three amorphous phases. Towards resolving the chemical identity of the three phases, we performed XRD analyses on samples subjected to dynamic heating, while further DSC and XRD analyses were performed on samples subjected to isothermal treatment. The results suggest that the three amorphous phases in G388 are Ca/Na–Al–Si–O, Ca–Al–F and Ca–P–O–F phases, respectively. However, the exact chemical compositions of the three phases still require further exploration. The results of this work are important for understanding the impact of phase separation within ionomer glasses on the setting behavior of GICs, and hence improving performances of GICs by optimizing the glass production conditions.

Structural and impedance characterization of ceramics prepared from NPK fertilizer

One of the main objectives of this work was to study the possibilities of valorising the phosphates through the development of a conductive ceramics using NPK fertilizer as a precursor. Phosphorus based powders were synthesized using solid state technique from NPK fertilizer, lithium chloride and iron chloride at different temperatures up to 900?C and ceramic samples were prepared by the powder pressing and sintering at 1100?C. XRD spectra of the calcined powders show various sharp peaks indicating a relatively high degree of crystallinity and presence of different crystalline phases, such as: phosphorus based crystalline compounds (AlPO4 and LiFePO4), ferrite (Fe3O4 and DyFeO3), CaSO4 and K3DyCl6. The prepared phosphorus based ceramics showed very interesting electrical and dielectric properties. Thus, in the future the obtained ceramics could find application in electronic or energy storage devices. However, further investigations are necessary to understand the exact chemical composition and structural characteristics of this material, to better understand the origin of the obtained electrical and dielectric behaviour.

ON THE MORPHOLOGY AND CHEMICAL COMPOSITION OF THE HR 4796A DEBRIS DISK

[abridged] We present resolved images of the HR 4796A debris disk using the Magellan adaptive optics system paired with Clio-2 and VisAO. We detect the disk at 0.77 \microns, 0.91 \microns, 0.99 \microns, 2.15 \microns, 3.1 \microns, 3.3 \microns, and 3.8 \microns. We find that the deprojected center of the ring is offset from the star by 4.76$\pm$1.6 AU and that the deprojected eccentricity is 0.06$\pm$0.02, in general agreement with previous studies. We find that the average width of the ring is 14$^{+3}_{-2}%$, also comparable to previous measurements. Such a narrow ring precludes the existence of shepherding planets more massive than \about 4 \mj, comparable to hot-start planets we could have detected beyond \about 60 AU in projected separation. Combining our new scattered light data with archival HST/STIS and HST/NICMOS data at \about 0.5-2 \microns, along with previously unpublished Spitzer/MIPS thermal emission data and all other literature thermal data, we set out to constrain the chemical composition of the dust grains. After testing 19 individual root compositions and more than 8,400 unique mixtures of these compositions, we find that good fits to the scattered light alone and thermal emission alone are discrepant, suggesting that caution should be exercised if fitting to only one or the other. When we fit to both the scattered light and thermal emission simultaneously, we find mediocre fits (reduced chi-square \about 2). In general, however, we find that silicates and organics are the most favored, and that water ice is usually not favored. These results suggest that the common constituents of both interstellar dust and solar system comets also may reside around HR 4796A, though improved modeling is necessary to place better constraints on the exact chemical composition of the dust.

Correlation Between Resistance to Carburization and Resistance to Oxidation of Selected High-Temperature Alloys

It is shown that a one-to-one correspondence exists between the resistance to carburization and resistance to oxidation of selected Cr2O3- and Al2O3-forming alloys as determined from carburization and oxidation tests. Although the Cr2O3-forming alloys are unable to maintain protective scales in an environment characterized by low oxygen potential and high carbon activity, the kinetics of carburization are found to be functions of the exact chemical composition. Ingress of carbon can lead to precipitation of carbides, particularly those based upon the Cr7C3 and Cr23C6 compositions with the latter enhancing the precipitation of CrFe sigma phase. In contrast, an Al2O3-forming alloy with balanced Ni, Cr and Al contents is found to have superior resistance to carburization due to: (i) formation of highly protective Y-modified oxide, and (ii) higher solubility of C. It is concluded that Al2O3-forming alloys can have a great deal of potential in applications requiring high resistance to carburization.

Light and atmosphere affect the Quasi-equilibrium states of graphite oxide and graphene oxide powders.

Graphite oxide (GiO) and graphene oxide (GeO) possess wide applicability in technological devices. The exact chemical compositions, structures, and properties of these materials remain vague to the graphene community despite being heavily researched. As metastable materials, the properties of GiO and GeO are easily manipulated under various conditions of temperature, light, and atmosphere. Although these aspects are important considerations for long-term storage of the materials, they are not well understood. In this experimental work, investigations are performed to determine how light and atmosphere contribute to the characteristics of GiO and GeO powders. The study shows that, at room-temperature, the quasi-equilibrium states of both materials, in specific the O/C ratios, vary according to the storage conditions. Drastic disparities between GiO and GeO are observed. GiO kept away from light and GeO kept under inert atmosphere maintain relatively high O/C ratios. As the metastable states of the materials are governed by the diffusion of oxygen functionalities, the presence of epoxide groups diminishes while negligible changes occur to the sp(2) lattice size. This experimental work lays out fundamental aspects that govern the stability of frequently mass-produced GiO and GeO powders under different environments, with major implications on their optimal storage conditions.

Computer-generated vegan menus: The importance of food composition database choice

Precise data on food chemical composition is crucial for any quantitative nutrition research and indispensable for evaluation and planning of computer-based menus. Moreover, exact food chemical composition is of the utmost importance in composing specific diets that may be low in certain essential nutrients. Therefore, this research evaluated a weekly vegan menu using three different food composition databases (FCDB): the Croatian, the official Danish Food Composition Database and the United States Department of Agriculture (USDA) – National Nutrient Database for Standard Reference. Significant differences (p<0.05) were determined in evaluated and optimised offers for the same menu when using different FCDBs. Furthermore, in these menus quantities of some nutrients have not reached official daily recommendations needed for prevention of non-communicable diseases. In this research, new vegan menus that can provide adequate quantity of essential nutrients, regardless of FCDB utilized, were created with linear optimisation (LO). This resulted in high quality daily menu offers. However, depending on the FCDB that was used, optimal menus differed in daily meal combinations, and the effectiveness of the optimisation in the minimisation of differences caused by differences of data in FCDBs was tested. Linear optimisation has been proved to be an effective tool in planning of specific diets, such as vegan diets. Nonetheless, the quality of computer-planned menus depends heavily on the quality of FCDB used.

FeS-Scale Cleanout With High-Pressure Coiled Tubing and Tailored Fluid

This article, written by Dennis Denney, contains highlights of paper SPE 169759, ’Extreme Challenges in FeS-Scale-Cleanout Operation Overcome Using Temporary Isolation, High-Pressure Coiled Tubing, and Tailored Fluid Systems,’ by Mustafa Buali, Noel Ginest, SPE, Jairo Leal, and Oscar Sambo, Saudi Aramco, and Alejandro Chacon and Jose Vielma, Halliburton—Boots &amp; Coots, prepared for the 2014 SPE International Oilfield Scale Conference and Exhibition, Aberdeen, 14-15 May. The paper has not been peer reviewed. The gas-producing carbonate zones of the Ghawar field in eastern Saudi Arabia have been affected by extensive iron sulfide (FeS) scale deposition, reducing overall gas production and increasing risks during well interventions. Previous remediation attempts used workover rigs, which can be costly because of the time necessary for workovers and lost production. Hydrogen sulfide (H2S) levels (2 to 5%) in the reservoir also contribute to higher costs and risks with the use of workover rigs. H2S in the reservoir poses a safety concern with the returns at surface and a concern with potential corrosion of the coiled tubing (CT) and completion. Therefore, the safest and most economical method was deemed to be mechanical descaling with CT. Introduction Two wells were descaled mechanically by use of CT. Each well involved four major challenges: low reservoir pressure, higher reservoir temperature, horizontal openhole completion, and highspecific- gravity (3.7 to 4.3) scale. The low reservoir pressure required payzone isolation to enable circulating out the heavy scale and to minimize fluid losses to the formation. With a bottomhole temperature as high as 310°F, the operational envelope of temporary chemical packers in combination with lost-circulation materials (LCMs) to isolate the openhole section had to be expanded. Following mechanical descaling with CT, the final challenge was cleaning out the LCM in the horizontal open hole and bringing the well back to maximum gas production by use of pinpoint stimulation techniques. Scale Composition Many scale samples have been collected and characterized throughout the years with X-ray diffraction (XRD), X-ray fluorescence, scanning electron micrographs, and microscopic methods (thin section). Although the exact chemical composition of the scale changes from well to well and varies with depth in a given well, the scale deposits are mixtures of many compounds, usually dominated by FeS minerals including pyrrhotite, troilite, mackinawite, greigite, pyrite, and marcasite.

Turbulent lifted flames of H2/N2 fuel issuing into a vitiated coflow investigated using Lagrangian Intermittent Modelling

This paper reports results of numerical simulations of a turbulent lifted jet flame of hydrogen–nitrogen mixtures including the effects of the autoignition. The impact of burned gases on the flame stabilization is analysed under the conditions of a laboratory jet flame in a vitiated coflow. In this study, mass flow rate, temperature and exact chemical composition of hot products mixed with air sent toward the turbulent flame base are fully determined. The effects of both non-infinitely fast chemistry and partially premixed combustion are taken into account within a Lagrangian intermittent framework. Detailed chemistry effects are incorporated through the use of a tabulation delay. The concept of residence time of the particles and the transport equation for the mean scalar dissipation rate are included. Numerical simulation of the turbulent diluted jet flame of H2/N2 studied by Cabra and his co-workers at Berkeley University is performed and satisfactory results are obtained: the flame liftoff height is reasonably captured and the predictions display a reasonable agreement with respect to experimental data.

Magnetic properties of La1−xSrxMnO3 nanoparticles prepared in a molten salt

Single phase La1−xSrxMnO3 nanoparticles (x = 0.18 − 0.37) are prepared by a novel way in molten NaNO2 at 500 °C. Their rhombohedral perovskite structure is confirmed by XRD patterns and exact chemical composition is determined by XRF (X-ray fluorescence) spectroscopy. The mean size of the as-prepared crystallites is of about 50 nm, the grains are rather separated and do not form sintering bridges that were typical for products synthesized by sol-gel routes followed by annealing. On the other hand, the synthesized nanoparticles exhibit rather low magnetization and decreased Curie temperature. Their neutron diffraction study indicates a complex magnetic ordering together with anomalously high atomic displacements factors that decreased considerably after annealing the samples at elevated temperature.

The first barium tin(II) bromide fluoride

In an effort to prepare barium tin(II) bromide fluorides for the first time, possibly similar to the chloride fluorides obtained earlier in our laboratory, precipitation reactions were carried out by mixing aqueous solutions of SnF2 and of BaBr2.2H2O. In contrast with the chloride fluoride system, a single powdered phase was obtained throughout the SnF2 – BaBr2 system, with the yield being maximum at X ≈ 0.25, where X is the molar fraction of barium bromide in the reaction mixture. Phase identification with the JCPDS database failed to produce a match, confirming that a new phase had been produced. The exact chemical composition of the new compound has not been obtained yet. Based on the X value for the maximum yield, the Sn/Ba ratio is likely to be 3/1 or 2/1. The Mossbauer spectrum at ambient conditions shows that bonding to tin(II) is covalent, therefore with the tin lone pair being stereoactive. The Mossbauer parameters (δ = 3.68 mm/s, Δ = 0.99 mm/s) are similar to those of SnBrF and of Sn2BrF5, thereby showing that tin is bonded to both fluorine and bromine. The larger isomer shift and lower quadrupole splitting than in tin(II) fluorides show that the stereoactivity of the tin lone pair is lower than in the fluorides. The Mossbauer parameters fit well the linear correlation of the quadrupole splitting versus the isomer shift” that has been shown to be present in other series of tin(II) compounds. The linear decrease on this correlation shows that the contribution of non-spherical orbitals (p and d) to the lone pair is a much larger contributor to the quadrupole splitting than lattice distortions. The structure is likely made of Ba2+ cations and tin(II) fluoride bromide polyatomic anions, with covalent bonding withinthe anions.

Mechanical properties of ground state structures in substitutional ordered alloys: High strength, high ductility and high thermal stability

We have studied the effect of atom arrangements in the ground state structures of substitutional ordered alloys on their mechanical properties using nickel–molybdenum-based alloys as model systems. Three alloys with nominal compositions of Ni–19.43at% Mo, Ni–18.53at% Mo–15.21at% Cr and Ni–18.72at% Mo–6.14at% Nb are included in the study. In agreement with theoretical predictions, the closely related Pt2Mo-type, DO22 and D1a superlattices with similar energies are identified by electron diffraction of ground state structures, which can directly be derived from the parent disordered fcc structure by minor atom rearrangements on {420}fcc planes. The three superlattices are observed to coexist during the disorder–order transformation at 700°C with the most stable superlattice being determined by the exact chemical composition. Although most of the slip systems in the parent disordered fcc structure are suppressed, many of the twinning systems remain operative in the superlattices favoring deformation by twinning, which leads to considerable strengthening while maintaining high ductility levels. Both the Pt2Mo-type and DO22 superlattices are distinguished by high strength and high ductility due to their nanoscale microstructures, which have high thermal stability. However, the D1a superlattice is found to exhibit poor thermal stability leading to considerable loss of ductility, which has been correlated with self-induced recrystallization by migration of grain boundaries.

Effect of synthesis method on structural, magnetic and magnetocaloric properties of La0.7Sr0.2Ag0.1MnO3 manganite

We report the morphological, structural, magnetic and magnetocaloric properties of La0.7Sr0.2Ag0.1MnO3 ceramics produced by the well-known sol–gel method combined to a sintering treatment at 1000 °C and by the conventional solid–solid method with a consolidation stage at 1200 °C. X-ray diffraction analysis evidenced a well crystallized manganite phase in both cases. Nevertheless a small contamination with Ag and Mn3O4 was observed in the first and second samples, respectively, making their exact chemical composition different. As a consequence, a substantial increase of the ferromagnetic to paramagnetic transition temperature and an enhancement of the relative cooling power were observed in the sol–gel made sample making it more suitable for magnetic refrigeration applications.