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ABSTRACTThe La1−xKxCo1−xNbxO3oxides were prepared by conventional solid state reaction technique. By using the GSAS programme a successful fit (Rp = 3.45%, Rwp = 2.77%, X2 = 1.28) was obtained, for x = 0.1. Refinements confirmed that K occupying the La sites and Nb for Co sites gave an acceptable occupancy factor for K and Nb. The valence state of all the ions in the system was determined by XPS analysis, and the lattice parameters were calculated according to the results of selected-area-diffraction (SAD) patterns and X-ray diffraction (XRD) identifications. The direction of the superlattice structure along [001] was found for x = 0.1 as identified from the SAD patterns.

The La1-xKxCo1-xNbxO3oxides were prepared by conventional solid state reaction technique. By using the GSAS programme a successful fit (Rp?=?3.45%, Rwp?=?2.77%, X2?=?1.28) was obtained, for x?=?0.1. Refinements confirmed that K occupying the La sites and Nb for Co sites gave an acceptable occupancy factor for K and Nb. The valence state of all the ions in the system was determined by XPS analysis, and the lattice parameters were calculated according to the results of selected-area-diffraction (SAD) patterns and X-ray diffraction (XRD) identifications. The direction of the superlattice structure along [001] was found for x?=?0.1 as identified from the SAD patterns.

To study the effect of refining slag on the compositions of molten steel and inclusions, the reaction between ship plate steel and different slag systems (slag A-CaO/Al2O3: 1.0, SiO2: 5 mass-% and slag B-CaO/Al2O3: 1.5, SiO2: 9 mass-%) was investigated by laboratory-scale high-temperature equilibrium experiments. Results showed that the desulphurisation capacity of the two slags was very similar, and the average sulphur content for both was 0.002 mass-% in steel, but the deoxidation capacity of slag B was slightly higher than slag A. The amount of inclusions <5 μm was more in steel balanced with slag B than in that balanced with slag A. To generate inclusions smaller than 5 μm, and spherical liquid CaO–MgO–Al2O3–SiO2inclusions, and to decrease the T[O] (total oxygen) content in steel, refining slag composition should be: CaO/Al2O3∼ 1.5, and SiO2∼ 9 mass-%. Slag system optimisation can reduce or even eliminate calcium treatment during production. T[O] content in the slab could be controlled to 15–21 ppm, with typical micro-inclusions of ≤10 μm, and CaO–Al2O3–MgO and CaO–Al2O3–CaS systems in molten steel.

FeCrNiCoBxhigh-entropy alloy coatings were prepared by laser cladding, and the effects of boron addition on the microstructure, hardness and corrosion resistance of the coatings were studied. Results showed that the coatings comprised a simple FCC solid solution with boride precipitation. When 0.5 ≤ x ≤ 1.0, (Cr, Fe)2B with an orthorhombic structure was found in the coatings, and the hardness and corrosion resistance of the coatings were enhanced by increasing boron content. As xapproached 1.25, the borides changed from orthorhombic (Cr, Fe)2B to tetragonal (Fe, Cr)2B, which deteriorated the corrosion resistance of the coatings. Stacking faults found in (Cr, Fe)2B may be caused by the phase transformation of borides.

To study the effect of refining slag on the compositions of molten steel and inclusions, the reaction between ship plate steel and different slag systems (slag A-CaO/Al2O3: 1.0, SiO2: 5 mass-% and slag B-CaO/Al2O3: 1.5, SiO2: 9 mass-%) was investigated by laboratory-scale high-temperature equilibrium experiments. Results showed that the desulphurisation capacity of the two slags was very similar, and the average sulphur content for both was 0.002 mass-% in steel, but the deoxidation capacity of slag B was slightly higher than slag A. The amount of inclusions <5 µm was more in steel balanced with slag B than in that balanced with slag A. To generate inclusions smaller than 5 µm, and spherical liquid CaO–MgO–Al2O3–SiO2inclusions, and to decrease the T[O] (total oxygen) content in steel, refining slag composition should be: CaO/Al2O3~ 1.5, and SiO2~ 9 mass-%. Slag system optimisation can reduce or even eliminate calcium treatment during production. T[O] content in the slab could be controlled to 15–21 ppm, with typical micro-inclusions of =10 µm, and CaO–Al2O3–MgO and CaO–Al2O3–CaS systems in molten steel.

FeCrNiCoBxhigh-entropy alloy coatings were prepared by laser cladding, and the effects of boron addition on the microstructure, hardness and corrosion resistance of the coatings were studied. Results showed that the coatings comprised a simple FCC solid solution with boride precipitation. When 0.5?=?x?=?1.0, (Cr, Fe)2B with an orthorhombic structure was found in the coatings, and the hardness and corrosion resistance of the coatings were enhanced by increasing boron content. As xapproached 1.25, the borides changed from orthorhombic (Cr, Fe)2B to tetragonal (Fe, Cr)2B, which deteriorated the corrosion resistance of the coatings. Stacking faults found in (Cr, Fe)2B may be caused by the phase transformation of borides.

Hypertensive disorders in pregnancy remain a leading cause of maternal and perinatal mortality and morbidity. We aim to study urotensin II (UII) and its association with the markers of endoplasmic reticulum stress (ERS) in placentas of patients with severe preeclampsia (SPE). Thirty-three patients with hypertensive disorders in pregnancy and twenty-two healthy pregnant women designated as healthy controls were recruited. Expression levels of UII, UII receptor (GPR14) and the markers of ERS in placenta specimens of patients were performed. Plasma and urinary UII levels were measured by radioimmunoassay method. Our study showed that the plasma levels of UII in patients with hypertensive disorders during pregnancy were significantly higher than that of the healthy control group. However, the urinary levels of UII had no difference in two groups. The expression level of mRNA and protein of UII, CCAAT/enhancer-binding protein homologous protein (CHOP) and glucose regulation protein 78 in placentas of SPE was significantly increased. Immunohistochemical analyses show that the expression levels of UII and ERS markers were mainly located in the cytoplasm of placental trophoblastic cells. Moreover, expression level of UII mRNA and protein was positively correlated with that of the markers of ERS. The positive correlation between UII and ERS markers expression level also corresponded with the level of patient’s systolic blood pressure and proteinuria. In conclusion, we first verify that expression of UII is associated with ERS in patients with SPE. Our results indicate that UII may trigger ERS in placental trophoblastic cells in patients with preeclampsia.

In this study, the effect of MgO content in slag on the phosphorus distribution ratios, and the equilibrium solubility of MgO in slag during converter steelmaking were analysed using the modified Kozheurov regular solution model and the thermodynamic package FactSage. Thermodynamic analysis shows that the MgO content in the final slag should be greater than 5% to saturate the slag with MgO and minimise the chemical wear of the refractory lining. However, the phosphorus distribution ratio decreases dramatically with increasing MgO. Industrial tests were performed using an 80-t top-and-bottom combined blown converter showed that the average phosphorus distribution ratio reduces significantly from 120.7 to 75.7 when the average MgO content in the final slag increases from 7.0 to 9.8%, due to thermodynamics and kinetics reasons. By optimizing the MgO content between 6 and 8% dephosphorisation and refractory wear are optimised.

In this study, the effect of MgO content in slag on the phosphorus distribution ratios, and the equilibrium solubility of MgO in slag during converter steelmaking were analysed using the modified Kozheurov regular solution model and the thermodynamic package FactSage. Thermodynamic analysis shows that the MgO content in the final slag should be greater than 5 to saturate the slag with MgO and minimise the chemical wear of the refractory lining. However, the phosphorus distribution ratio decreases dramatically with increasing MgO. Industrial tests were performed using an 80-t top-and-bottom combined blown converter showed that the average phosphorus distribution ratio reduces significantly from 120.7 to 75.7 when the average MgO content in the final slag increases from 7.0 to 9.8, due to thermodynamics and kinetics reasons. By optimizing the MgO content between 6 and 8 dephosphorisation and refractory wear are optimised.

During the continuous casting (CC) of Al containing resulphurised steel, the submerged entry nozzle is often clogged by high melting point inclusions such as MgO.Al2O3spinel and CaS. Casting extended for only one to two heats before optimisation. The main objective of the present study is to improve the castability of this steel. A suitable refining slag composition was sought and designed thermodynamically, and a soft blowing system was improved for reducing the dynamics of steel–slag desulphurisation. An optimisation plant trial was conducted on a sequence with four heats. By adopting the optimised refining slag and improved soft stirring operation, the steel castability was improved and the number of CC heats of a single tundish was increased from 1–2 to more than 4.

Calcium treatment is an important parameter in solving nozzle clogging during continuous casting of Al containing steel. In this study, the process of slag washing was optimised in order to control the compositions of the refining slag. The results showed that the total oxygen (T[O]) content in the casting slab could be controlled to 13–23 ppm and the nitrogen ([N]) content to 21–47 ppm. The total number of macroinclusions in the slab was also reduced to 9·82 mg 10 kg-1of steel. The typical size of microinclusions in the steel without calcium treatment was <5 µm in the MgO–Al2O3, SiO2–Al2O3systems, and only a small amount of Al2O3was found. The rolled metals therefore met the quality and performance requirements of a high strength low alloy steel for engineering applications. Thus, by eliminating the need for calcium treatment, production costs could be reduced significantly, and the cleanliness of the molten steel could be improved.

In 2011 the last phase in the installation of the PRACLAY In-Situ Experiment in the underground research facility HADES (Mol, Belgium) was completed. The main goal of the experiment is to perform a large-scale in-situHeater Test. The Heater Test will examine the effect of the thermal load generated by heat-emitting waste on Boom Clay, currently considered as a potential host rock in the Belgian R&D programme for geological disposal. In 2007 the PRACLAY gallery was constructed to host the Heater Test. In 2010 a bentonite-based hydraulic seal was installed in this gallery, isolating the heated part from the non-heated part of the PRACLAY gallery. The primary objective of the seal is to provide undrained hydraulic boundary conditions for the Heater Test. As the performance of the seal is crucial to the Heater Test, it has been instrumented accordingly. The seal also provides an opportunity to gather additional information on the in-situbehaviour of bentonite-based repository structures. Finally the placement of a heating system and water-saturated sand in the heated section of the PRACLAY gallery completed the experiment installation. The water-saturated backfill sand has to assure undrained hydraulic boundary conditions at the interface between the clay and the gallery lining.

One therapeutic approach to stroke is the transplantation of cells capable of trophic support, reinnervation, and/or regeneration. Previously, we have described the use of novel truncated isoforms of SV40 large T antigen to generate unique cell lines from several primary rodent tissue types. Here we describe the generation of two cell lines, RTC3 and RTC4, derived from primary mesencephalic tissue using a fragment of mutant T antigen, T155c (cDNA) expressed from the RSV promoter. Both lines expressed the glial markers vimentin and S100β, but not the neuronal markers NeuN, MAP2, or β-III-tubulin. A screen for secreted trophic factors revealed substantially elevated levels of platelet-derived growth factor (PDGF) in RTC4, but not RTC3 cells. When transplanted into rat cortex, RTC4 cells survived for at least 22 days and expressed PDGF. Because PDGF has been reported to reduce ischemic injury, we examined the protective functions of RTC4 cells in an animal model of stroke. RTC4 or RTC3 cells, or vehicle, were injected into rat cortex 15–20 min prior to a 60-min middle cerebral artery ligation. Forty-eight hours later, animals were sacrificed and the stroke volume was assessed by triphenyl-tetrazolium chloride (TTC) staining. Compared to vehicle or RTC3 cells, transplanted RTC4 cells significantly reduced stroke volume. Overall, we generated a cell line with glial properties that produces PDGF and reduces ischemic injury in a rat model of stroke.

The first class of zipper-shaped artificial duplexes, which are driven by multiple donor−acceptor interactions between electron-rich 1,5-dioxynaphthalene or 1,4-dioxybenzene and electron-deficient pyromellitic dimide units, have been studied in organic media by ¹H NMR, UV−vis, and vapor pressure osmometry. ¹H NMR binding investigations reveal substantial cooperativity of the donor−acceptor interaction in the duplexes.

Interfacial tension data of (CH4 + N2) + H2O and (CO2 + N2) + H2O systems were measured using a pendant-drop method. The temperature and pressure ranges were 298−373 K and 1−30 MPa, respectively. The effects of gas composition, temperature, and pressure on the interfacial tension of the systems studied have been investigated. The linear gradient theory (LGT) was used to calculate the interfacial tensions of these two systems. The results show good agreement between the calculated and experimental interfacial tension data for the (CH4 + N2) + H2O system. However, it was found that the LGT model with one adjustable parameter is inadequate to give accurate predictions for the CO2 + H2O system and thus is not suitable for the description of the (CO2 + N2) + H2O system.

Hydrate formation conditions of hydrogen + hydrocarbon gas mixtures (H2 + CH4, H2 + C3H8, H2 + CH4 + C3H8, and H2 + CH4 + C2H6 + C3H8) in pure water have been measured in a sapphire cell using the “pressure search” method. The experimental temperature range was (274−280) K, and the pressure-range was (0.65−7.0) MPa. The hydrogen content in the gas mixtures varies from 22 mol % to 92 mol %.

Our study showed that hemodilution with modified fluid gelatin resulted in an increase in local cerebral blood flow (LCBF), but no change at all in local cerebral oxygen delivery (LCOD) in rats. Hemosome, a lecithin encapsulated hemoglobin having the oxygen-carrying capacity, was developed to improve LCOD by hemodilution. Therefore, we have hypothesized that LCBF & LCOD would be increased by hemodilution with hemosome . To test this hypothesis, adult male Sprague-Dawley rats weighing ∼350g were used and divided into the hemodilution and the control groups Hemosome was made from pig red blood cells and lecithin. It's mean diameter was ∼0.3urn and hemoglobin concentration was ∼4g/dl. Isovolemic hemodilution, which lowered the systemic hematocrit from ∼50% to ∼30%, was achieved by rapidly replacing blood with the same volume of hemosome. Ten min later, LCBF in 14 brain structures were measured using the 14C-iodoantipyrine technique Our results showed that LCBF of the control group ranged from 115±1 Iml/100g/min in the medulla to 260±31 ml/100g/min in the occipital cortex. LCBFs were generally higher (p<0 05, MANOVA) by 16% in the hemodilution group than in the control group However LCODs were generally decreased (p<0.05, MANOVA) by 18% in the hemodilution group than in the control. In conclusion, hemodilution with hemosome indeed improves LCBF but lowers LCOD in awake rats.

The efficiency of simian virus 40 (SV40) DNA replication is dependent on the structural organization of the regulatory region. The enhancing effect of the G + C-rich 21-base-pair (bp) repeats on SV40 DNA replication is position and dose dependent and to some extent orientation dependent. The inverted orientation is about 50% as effective as the normal orientation of the 21-bp repeat region. Movement of the 21-bp repeat region 180 or 370 bp upstream of the ori sequence abolishes its enhancing effect, whereas no replication is detected if the 21-bp repeat region is placed downstream of the ori sequence. The dose-dependent enhancement of the 21-bp repeat of SV40 DNA replication as first described in single transfection by Bergsma et al. (D. J. Bergsma, D. M. Olive, S. W. Hartzell, and K. N. Subramanian, Proc. Natl. Acad. Sci. USA 79:381-385, 1982) is dramatically amplified in mixed transfection. In the presence of the 21-bp repeat region, the 72-bp repeat region can enhance SV40 DNA replication. In the presence of the 21-bp repeats and a competitive environment, the 72-bp repeat region exhibits a cis-acting inhibitory effect on SV40 DNA replication.

A selective replicative pressure occurs during the evolution of simian virus 40 variants. When the replication origin is duplicated as an inverted repeat, there is a dramatic enhancement of replication. Having regulatory sequences located between the inverted repeat of ori magnifies their enhancing effect on replication. A passage 20 variant and a passage 45 variant containing three pairs of an inverted repeat of ori replicated more efficiently than a passage 13 variant containing nine copies of ori arranged in tandem. A 69-base-pair cellular sequence inserted between inverted repeats of ori of both passage 40 and 45 variants enhanced simian virus 40 DNA replication. Differences in replication efficiencies became greater as the total number of replicating species was increased in the transfection mixture, under conditions where T antigen is limiting. In a competitive environment, sequences flanking the replication origin may be inhibitory to replication.

This paper presents further theoretical analysis and developments of entropy-based methods for mathematical programming. A new generalized multiplier function is given which approximates uniformly the maximum function, and from which the aggregate function is derived in a different way. Some new methods for minimax and constrained nonlinear programming problems are proposed. The convergence properties for these methods are discussed.

Mixed ruminal bacteria (80 mg N/liter) degraded casein and soluble soy protein rapidly (.68 and .72 mg N/liter•min], respectively), but ammonia was produced at a slower rate (.08 and .10 mg N/[liter•min], respectively). Because there was little increase in cell protein, ammonia production could not account for all the degraded protein. Large quantities of non-ammonia, non-protein nitrogen (NAN-NPN) accumulated, and this NAN-NPN reacted more strongly (2- to 14-fold) with ninhydrin after it was treated with 6 N HC1 (110°C, 24 h) or pronase E. Even after 96 h of incubation, 10% of the protein N was still found in the NAN-NPN pool. Monensin had little effect on protein degradation, but it caused a large decrease in ammonia production (P < .05) and an increase in NAN-NPN (P < .05). These results indicated that significant quantities of peptide N could not be degraded by ruminal microorganisms and that monensin could increase peptide flow from the rumen. Because 3,3',4',5-tetrachlorosalicylanide, a protonophore that inhibits both Gram-positive and Gram-negative bacteria, did not cause a greater decrease (P > .05) in ammonia than monensin, an ionophore that is primarily effective against Gram-positive bacteria, it seemed that the “protein sparing” of monensin could largely be explained by its inhibition of Gram-positive bacteria.

BiP is a member of the Hsp70 heat shock protein family found in the lumen of the endoplasmic reticulum, that binds to a variety of proteins destined to be secreted. Substance P (SP) has been used as a model peptide to study the interaction of BiP with protein substrates. SP stimulates BiP ATPase activity and forms a stable complex with BiP that is dissociated in the presence of levels of ATP > 50 microM. At lower concentrations of ATP, the SP remains bound to BiP, and the results are consistent with the view that a BiP-ATP complex is initially formed that reacts with SP to form a ternary complex, SP-BiP-ATP. Hydrolysis of ATP in this complex yields a SP-BiP-ADP complex. An exchange of ATP with ADP bound to BiP has also been demonstrated, and the results suggest that the interactions of BiP with ATP resemble those seen with GTP-binding proteins and GTP.

Streptococcus bovis JB1 cells energized with glucose transported glutamine at a rate of 7 nmol/mg of protein per min at a pH of 5.0 to 7.5; sodium had little effect on the transport rate. Because valinomycin-treated cells loaded with K and diluted into Na (pH 6.5) to create an artificial delta psi took up little glutamine, it appeared that transport was driven by phosphate-bond energy rather than proton motive force. The kinetics of glutamine transport by glucose-energized cells were biphasic, and it appeared that facilitated diffusion was also involved, particularly at high glutamine concentrations. Glucose-depleted cultures took up glutamine and produced ammonia, but the rate of transport per unit of glutamine (V/S) by nonenergized cells was at least 1,000-fold less than the V/S by glucose-energized cells. Glutamine was converted to pyroglutamate and ammonia by a pathway that did not involve a glutaminase reaction or glutamate production. No ammonia production from pyroglutamate was detected. S. bovis was unable to take up glutamate, but intracellular glutamate concentrations were as high as 7 mM. Glutamate was produced from ammonia via a glutamate dehydrogenase reaction. Cells contained high concentrations of 2-oxoglutarate and NADPH that inhibited glutamate deamination and favored glutamate formation. Since the carbon skeleton of glutamine was lost as pyroglutamate, glutamate formation occurred at the expense of glucose. Arginine deamination is often used as a taxonomic tool in classifying streptococci, and it had generally been assumed that other amino acids could not be fermented. To our knowledge, this is the first report of glutamine conversion to pyroglutamate and ammonia in streptococci.

An attempt is made in this work to combine the Enskog theory of transport properties with the simple cubic Peng-Robinson (PR) equation of state. The PR equation of state provides the density dependence of the equilibrium radial distribution function. A slight empirical modification of the Enskog equation is proposed to improve the accuracy of correlation of thermal conductivity and viscosity coefficient for dense gases and liquids. Extensive comparisons with experimental data of pure fluids are made for a wide range of fluid states with temperatures from 90 to 500 K and pressures from 1 to 740 atm. The total average absolute deviations are 2.67% and 2.02% for viscosity and thermal conductivity predictions, respectively. The proposed procedure for predicting viscosity and thermal conductivity is simple and straightforward. It requires only critical parameters and acentric factors for the fluids.

The carbon dioxide (CO2) injection method has been used to enhance oil recovery from Chinese reservoirs. Reservoir fluid was first prepared by combining the gas and liquid phase using the gas−oil ratio data. The influence of CO2 molar composition (xCO2) on the interfacial tension of the CO2 injected crude oil + reservoir water under stratum conditions was studied using a pendant drop method, where xCO2 was from (0, 10.0, 34.1, 44.7, 48.9, 57.8, to 65.0) mol %. The bubble point pressure for these CO2 injected oil systems was also determined using a RUSKA PVT device, which could be used to keep the measured system under single-phase conditions. The experimental data showed that when xCO2 changed from (0 to 65.0) mol %, the interfacial tension value decreased by about one-third. The pressure had a slight effect on the interfacial tension. When xCO2 was 65.0 mol %, the CO2 injected oil system approached complete miscibility and the interfacial tension data of CO2 injected crude oil + reservoir water changed a little with an increase of pressure.

Hydrate formation conditions of (H2 + CH4) binary gas mixtures in the presence of tetrahydrofuran (THF) in water were measured in a sapphire cell using the “pressure search” method. The experimental temperature ranged from 277.7 K to 288.4 K, and pressure ranged from 0.12 MPa to 8.86 MPa. The hydrogen composition in the gas mixture varied from 0 mol % to 97.85 mol %. The THF content in the aqueous solution was fixed at 6 mol %.

Interfacial tension of methane + water with surfactant near the hydrate formation conditions were measured using the pendant-drop method at 273.2 K and 278.8 K and in the pressure range of (0.4 to 9.5) MPa. The concentrations of sodium dodecyl sulfate (SDS) were 100 ppm, 300 ppm, 500 ppm, 700 ppm, and 1000 ppm. It was found that the interfacial tension of the solutions decreases steeply with the addition of SDS. When the SDS concentration is about 500 ppm, the surfactant concentration reaches a critical micellar concentration of the methane + water solution. Surfactant molecules associate as micelles, and the interfacial tension remains constant with further increase in SDS concentration.

Hydrate formation conditions of (CH4 + CO2 + H2S) ternary sour natural gas mixtures in the presence of pure water were measured. The experimental temperature range was (274.2 to 299.7) K, and the pressure range was (0.58 to 8.68) MPa. The hydrogen sulfide and carbon dioxide contents in the gas mixtures varied from (4.9 to 26.6) mol % and from (6.8 to 10.8) mol %, respectively.

Interfacial tension for (CO2 + CH4) + water systems are reported for five gas compositions in the temperature range of (298−373) K and pressure range of (1−30) MPa. The effects of gas composition, temperature, and pressure on the interfacial tension of the studied systems are reported.