Miracle-dz/UniFAR-FTUs huggingface dataset:
METHANE FLAME PROPAGATION IN COMPOSITIONALLY STRATIFIED GASES

ABSTRACT Flame propagation in compositionally stratified methane-air mixtures was studied experimentally as a function of the equivalence ratio distribution in the unburnt mixture. Stratification was established in a controlled manner using a convective-diffusive balance in a very slow fuel-air mixture flow in an optically accessible test chamber. The flame speed was shown to be significantly higher than the one corresponding to a homogeneous mixture of the local equivalence ratio for mixture compositions close to the lean flammability limit. Also a significant extension of the lean flammability limit was observed. It was established that the local spatial gradient of the equivalence ratio was not sufficient to describe the departure of stratified combustion from quasi-homogeneity. Instead, an appropriately defined integral parameter that depended on the history of flame propagation was shown to determine when the flame could not be treated as a series of premixed flamelets propagating at the local adiabatic flame speed.
The Danish Twin Apartment Study; Part I: Formaldehyde and Long‐Term VOC Measurements

Field measurements of 21 volatile organic compounds (VOC) using diffusive samplers, formaldehyde, temperature, and humidity were performed from the time of building completion throughout the following one-year period in two new semi-detached twin apartments. One of these was occupied after six weeks. Headspace analyses from all building materials and products showed 120 different VOC. Formaldehyde concentrations were strongly seasonally dependent in the vacant apartment and increased to above 400 μg/m3 during the warm season. The formaldehyde concentration generally decreased in the occupied apartment but increased again during the fall season. VOC originating from building materials generally showed a decrease in emission, but strong seasonal variations were observed. It was shown that human activity introduces several VOC to the indoor environment. Storage of motorcycle parts in the crawl space of the occupied apartment resulted in migration and an infiltration of benzene and toluene into the apartment above and probably to a delayed peak concentration in the twin vacant apartment. Similarly, large VOC increases in one apartment were reflected by a later increase of the same VOC in the twin apartment. Hexanal increased during the warm season. TVOC, as the sum of 21 VOC, was generally approximately 50 % higher in the occupied apartment during the cold season. The results indicate the difficulties in interpreting long-term measurements. The “flushing period” recommended for this type of building has been estimated to be about 130 days.
THERMAL INSTABILITY OF ROTATING NANOFLUID

The onset of convection in a horizontal layer of nanofluid the presence of rotation is investigated. The onset criterion for stationary and oscillatory convection is derived analytically and graphically. Normal mode analysis and Galerkin method of first approximation are used to find solution of the fluid layer confined between two free boundaries. The effects of the Taylor number, concentration Rayleigh number, Prandtl number and Lewis number on the stability of the system are investigated. Regimes of stationary and oscillatory convection for various parameters are derived and are discussed in detail. The sufficient conditions for the non-existence of overstability have also been obtained.
Multistate Redox‐Active Metalated Triarylamines

trans-[(η5-C5H5)Fe(η5-C5H4-η1-C≡C)Ru(C≡C-4-C6H4NPh2)(dppe)2] [4; dppe = 1,2-bis(diphenylphosphanyl)ethane] and trans,trans,trans-[{(η5-C5H5)Fe(η5-C5H4-η1-C≡C)Ru(dppe)2(C≡C-4-C6H4)}3N] (7) have been synthesized from trans-[Ru(C≡C-4-C6H4NPh2)Cl(dppe)2] (3) and trans,trans,trans-[{(dppe)2ClRu(C≡C-4-C6H4)}3N] (6), respectively, and the identities of trans-[Ru(C=CH-4-C6H4NPh2)Cl(dppe)2][PF6] (2, precursor to 3), 3, and 4 have been confirmed crystallographically. Chemical oxidation of 4 and 7 afforded the isolable mixed-valence species 4[PF6] and 7[PF6]3. The CV of 4 reveals sequential loss of three electrons in fully reversible oxidation steps, whereas the CV of 7 shows five reversible redox waves; in contrast, oxidation of the precursor amines HC≡C-4-C6H4NPh2 and (HC≡C-4-C6H4)3N are irreversible processes. All oxidation processes afford reversible changes in the linear optical properties. Complementary time-dependent density functional theory (TD-DFT) studies suggest that the initial oxidation process for 4 and 7 is iron-centered and is followed by one (for 4) or three (for 7) ruthenium-centered oxidations. The final reversible oxidation is assigned by TD-DFT as delocalized along the metalla-ethynylarylamine moiety. The intense optical changes consequent on reversible oxidation, together with their charge-transfer character, suggest that 4 and 7 have potential as nonlinear as well as linear optical multistate switches.
Availability and Persistence of Macronutrients from Lime and Preplant Nutrient Charge Fertilizers in Peat-based Root Media

Using incubation and container culture with subirrigation for up to 28 days, three experiments were conducted with six liming materials of different particle sizes and six blended preplant nutrient charge (PNC) fertilizers. Liming material, particle size, and incorporation rate had an effect on the initial pH (3.5 to 6.1) and the final stable pH (4.8 to 7.8) with one type of Canadian sphagnum peat that did not contain an incorporated PNC. Saturated media extract (SME) Ca and Mg concentrations were <25 and 15 mg·liter -1 , respectively, for both pulverized and superfine dolomitic lime at incorporation rates up to 7.2 kg·m -3 . For the blended PNC fertilizers in media containing lime, initial electrical conductivity (EC) and SME nutrient concentrations ranged from (EC) 1.0 to 2.9 dS·m -1 , (mg·liter -1 ) 60 to 300 N, 4 to 105 PO 4 -P, 85 to 250 K, 120 to 400 Ca, and 60 to 220 Mg. However, within two days, the rapid stratification of fertilizer salts within the pot caused macronutrient concentrations to increase in the top 3 cm of root medium (top layer) by an average of 180% and decrease in the remaining root medium in the pot (root zone) by an average of 57% compared to that measured in the medium at planting. Nutrient concentrations in the top layer continued to increase even when those in the root zone fell below acceptable levels recommended for an SME. The importance of fertilizer salt stratification within a pot lies in the reduced availability of nutrients to the plant and illustrates the limited persistence of the PNC fertilizers. Testing nutrients in container media several days after planting rather than in freshly mixed media may be more representative of the starting point for a nutritional management program.
Au/CuO nanosheets composite for glucose sensor and CO oxidation

Au nanoparticles/mesoporous CuO nanosheets were successfully synthesized by the assembly of negatively charged AuCl4−1 and positively charged CuO nanosheets using sodium citrate and thermal reduction, respectively. The structure and morphology were characterized in detail. Both the loading amount of Au nanoparticles and the performance were controlled by the reduction process. The resulting Au/CuO NSs exhibited good catalytic activity for CO oxidation and good non-enzymatic sensitivity for glucose.
Escarificação mecânica e biológica para a redução da compactação em argissolo franco-arenoso sob plantio direto

Soil management alters the physical soil properties and changes the soil air, water, and solute dynamics. Physical soil properties as affected by conservationist soil management systems were studied in a sandy loam Typic Hapludalf. The treatments were established on a soil that has been under no-tillage for 10 years, and consisted of: no-tillage soybeans, chisel tillage soybeans, reduced tillage Crotalaria, and bare soil without tillage. The evaluated soil properties were soil penetration resistance, bulk density, porosity, pore size distribution, saturated and unsaturated hydraulic conductivity, water infiltration using concentric rings or natural rainfall, variation of the volumetric soil moisture throughout the cropping cycle, and water retention curve. Soil penetration resistance (PR) was highest at 0.075 m and 0.175 m depth in no-tillage and chiseled soil, respectively. Soil subsurface mobilization with chiseling and surface mobilization due to disking and sowing did not influence the bulk density (BD) after the crop harvest. No-till soil under soybean crop had greater macroporosity than reduced tillage crotalaria and bare soil at 0.02 to 0.05 m depth, resulting in a greater saturated hydraulic conductivity and lower water retention during periods of low water availability. Among the analyzed soil physical-mechanical properties, PR seemed to be more sensitive to detect soil compaction than BD or porosities, particularly for thinner soil layers. The effectiveness in rupturing compacted soil depended on the hydraulic or mechanical soil property used as indicator. When using K(qs) as indicator, in the medium term (4.5 months), "biological chiseling" by Crotalaria roots was more efficient at ameliorating soil compaction and establishing a network of conductive pores compared to mechanical chiseling. However, inverse results were observed when PR was used as indicator. Thus, the choice of a soil physical property as indicator to evaluate the effectiveness of compaction reduction depends on which physical process is considered more important: water infiltration and redistribution or root penetration and growth.
The Double Borates Ba3Ln(BO3)3, Ln=La–Lu, Y

New compounds of the compositions Ba3Ln(BO3)3, Ln=La–Lu, Y were obtained in the ternary systems BaO–Ln2O3–B2O3. Single crystals were grown for Ba3Yb(BO3)3. X-ray diffraction analysis showed a hexagonal structure with space group P63cm and lattice parameters a=9.411(1), c=17.481(5) A, Z=6. The compounds with Ln=Dy–Lu, Y also crystallize in the space group P63cm. New temperature data on melting points and unit-cell dimensions were obtained for each compound. The borates with Ln=La–Tb are isostructural and crystallize in the space group R3. Optical second harmonic generation (SHG) measurements of laser radiation showed that Ba3Yb(BO3)3 has type I phase transition. By investigation of the crystals of the double borate Ba3Yb(BO3)3 it was established that the compound possesses a pyroelectric effect.
Effects of different fertilizer sources on vegetative characteristics of pot marigold plant (Calendula officinalis L.)

Medicinal plants are one of very valuable resources in wide range of natural resources of Iran that it can have an important role in health. In order to investigate the effect of nitrogen fertilizer and zinc sulfate on vegetative characteristics of Calendula Officinalis, as factorial experiment based on randomized complete block design was carried out with three replications in Takestan, Iran during 2010-2011 cropping season. The experimental factors were consisted of nitrogen fertilizer (manure and urea) with 5 levels (0 tons of manure + 120 kg.ha-1urea, 10 tons of manure + 90 kg.ha -1 urea, 20 tons of manure + 60 kg.ha -1 urea, 30 tons of manure + 90 kg.ha -1 urea and 40 tons of manure + 0 kg.ha -1 urea) and zinc sulfate of 3 levels (no spraying, once spraying and twice spraying). The results showed that the effect of nitrogen fertilizer (manure and urea) and zinc sulfate was significant on number of stem sub, leaf dry weight, stem dry weight, capitulum dry weight and flower yield. The highest flower yield was obtained from 20 tons manure + 60 kg.ha-1 urea with the amount of 77.96 g.m-2. In the case of zinc Sulfate, was obtained the maximum yield flower with twice spraying, the amount of 78.05 g g.m-2, interaction between treatments had no significant effect on shoot weight and flower yield. The maximum flower yield was obtained from combination treatment of 20 tons of manure + 60 kg.ha -1 urea and twice spraying zinc to amount
Effect of Ultrasonication on Stability of Oil in Water Emulsions

Effect of ultrasonic waves on stability of oil in water system of light liquid paraffin oil (HLB = 12) as internal phase and tween20 (HLB = 16.7), span20 (HLB = 8.6) as emulsifying agents was studied. A comparison was made to determine the stability of emulsions prepared by mechanical agitation method and ultrasonication technique. Droplet size measurement method was used to determine the stability of emulsions. Physico-chemical parameters like concentration of emulsifying agent, volume fraction of dispersed phase, viscosity of continuous phase by adding glycerin to water were compared apart from the effect of emulsification time on stability of emulsions prepared with mechanical stirring and ultrasound. Ocular micrometer was used to determine the droplet size of the dispersed phase.Emulsions prepared by ultrasonic technique were found to be more stable for longer duration of time when compared to emulsions prepared by mechanical agitation which can be attributed to the small droplet size which is thermodynamically stabilized.Ultrasonic technique gave more stable emulsions than with mechanical agitation method. Emulsification time, volume fraction of dispersed phase, viscosity of continuous phase and concentration of emulsifying agents played a major role in the stability of emulsions. Keywords: Liquid paraffin, Tween 20, Span 20, emulsification, ultrasound technique, volume fraction of dispersed phase
Gas entrainment rate and flow characterization in downcomer of a Jameson cell

The Jameson cell which is a new type of gas-liquid contacting device and can be considered as a type of plunging jet column, has been in use worldwide for the separation of fine minerals, coal particles and wastewater treatment etc. Flow characteristics in the downcomer of a Jameson cell are very important since the hydrodynamics of the cell is largely depends on the flow conditions. The hydrodynamics influences flow regimes in the downcomer and hence the gas holdup and bubble diameter are strongly affected by flow conditions. Depending on the air entrainment rate entered to the system, different flow regimes are observed in the downcomer. Bubbly flow which is observed at less air quantities is desired instead of churn-turbulent flow where the gas entrainment rate increase. In this research, the effect of operating conditions including nozzle diameter, downcomer diameter, jet velocity and jet length on gas entrainment rate, Qg , was evaluated experimentally for an air-water system for the bubbly and churn-turbulent flow. Between these factors, downcomer diameter was found to have very little effect on gas entrainment rate while increasing values of other factors had an increasing effect on it. The results were evaluated by forward stepwise linear regression (MLR) and a piecewise regression with Quasi-Newton estimation of breakpoint (PLR) to estimate the flow conditions and gas entrainment rates. The model by PLR was useful to understand the boundary of the flow characteristics since the two equations were valid in a certain air entrainment ranges, i.e. different flow conditions. The model developed was successful to determine the transition region from bubbly flow to churn-turbulent flow. Experimental data were in good agreement with theoretically predicted value.
Effect of Salt and Storage Time on Physico-Chemical and Sensorial Properties of Beef Meatball

The experiment was conducted to find out the effect of salt and storage temperature on the physico-chemical properties of meatball. For this purpose meatball samples were divided into two parts; one is called fresh meatball and another is preserved meatball at different temperatures. Then the fresh samples as well as the preserved samples were divided into four subdivisions. Then these are treated with different salt levels (0, 1.5, 3 and 5% salt level). These Samples were stored at 4 o C and -20 o C temperature. Samples preserved at 4 o C were stored in the refrigerator for 21 days and were analyzed on 7 th day, 14 th day and 21 st day and samples preserved at -20 o Cwere stored in the refrigerator for 60 days and were analyzed on 15 th day, 30 th day, 45 th day and 60 th day. Dry matter content of all the samples increased with the advancement of storage time, temperature and salt concentration. Ash value decreased with the increase of storage time. Fat value of all the samples decreased with the advancement of salt concentration, storage time and temperature. pH value of all the samples decreased with the increasing of salt concentration, storage time and temperature. Cooking loss of all the samples increased with increasing of salt concentration but decreased with increasing of storage time and temperature. Dry matter in fresh sample were less than in preserved samples. CP % of fresh beef meatball was 22.31, 20.55, 14.55 and 20.13 at different salt concentration. The values of CP, DM, Ash and Fat also varied among the samples significantly (P<0.01). Beef meatball can be refrigerated for 60 days in different techniques with more or less difference in the quality. Highly significant differences are observed in preserved samples than in fresh samples at different salt levels. Fresh beef meatball treated with 1.5% salt found to be more acceptable in terms of sensory evaluation. DOI: http://dx.doi. org/10.3329/pa.v24i1-2.19117 Progress. Agric. 24(1&2): 137 - 147, 2013
Effects of binary particle size distribution on the fluid dynamic behavior of fluidized, vibrated and vibrofluidized beds

In this work the effects of particle size distribution on the dynamics and segregation patterns in fluidized, vibrated and vibrofluidized beds were investigated. A binary particle size distribution and a reference one composed of glass spheres with a mean Sauter diameter of 2.18×10-3 m were tested. The experimental setup consisted basically of a circular glass chamber with a height of 0.50 m and a diameter of 0.114 m, operated in the fluidized bed mode (G = 0.00), in either vibrated or vibrofluidized bed modes (G = 2.00). The pressure drops in the fluidized and vibrofluidized beds were not significantly affected by the binary particle size distribution. Well-defined segregation patterns occurred in fluidized and vibrated beds with small particles concentrating at the top and large particles at the bottom in the first situation and the reverse in the second one. Segregation patterns in vibrofluidized beds depended on the values of vibration parameters. Segregation in vibrofluidized and vibrated beds was minimized by operating at a high amplitude of vibration.
Effect of solvent on cis‐to‐trans isomerization of 4‐hydroxyazobenzene aggregated through intermolecular hydrogen bonds

The half-life (τ1/2) for thermal isomerization of cis-4-hydroxyazobenzene (c-HOAB) to its trans isomer is highly dependent on the solvent used. For non-aromatic solvents, the cis isomer is extremely unstable at 293 K (τ1/2 < 1 min in methanol and acetonitrile and 6 min in cyclohexane), whereas the cis isomer is surprisingly stable in benzene (τ1/2 = 125 min). However, addition of hydrogen chloride and triethylamine in benzene causes a remarkable decrease in τ1/2. On the basis of ab initio molecular orbital calculations of the binding energies and the optimum structures of c-HOAB–solvent complexes, a mechanism for the thermal cis-to-trans isomerization reaction involving hydrogen-bonded dimers and complexes is suggested. Copyright © 2005 John Wiley & Sons, Ltd.
EXPERIMENTAL AND SIMULATED P TRANSPORT IN SOIL USING A MULTIREACTION MODEL

A miscible displacement technique was used to investigate the mobility of P in columns of Bh soil materials from two dairies in the Lake Okeechobee Basin. Phosphorus-laden solutions with four (5, 10, 50, and 100 g m−3) initial concentrations (C0) were applied to soil columns. An increase in the value of C0 increased P mobility as determined by BTCs. Shapes of BTCs were characteristic of kinetically-controlled nonlinear sorption reactions, i.e., early breakthrough, clockwise rotation, and tailing. A 2-site sorption/transport model with fast and slow sorption kinetics was calibrated from the BTC for one of the four C0 values for each of two soils and then used to simulate BTCs for the other three C0 values. Simulations based on the two highest C0 values compared favorably to observed BTCs for all but the lowest C0 value. Simulations based on the two lowest C0 values compared favorably only to the BTCs at that C0 value. Thus the sorption rate coefficients were not independent of influent C0 for these two soils. Phosphorus retardation was underestimated for simulations of C0 = 11, 51, and 97 g m−3 using k1, k2, and f input parameters obtained by calibration using the BTC for C0 = 5 g m−3 and it was overestimated for simulation of C0 = 5 g m−3 when input parameters for the model were obtained by calibrating using the BTCs for the three highest C0 values. Experimental enhancement of early P breakthrough in effluent from columns that received C0 = 5 g m−3 was attributed to the initial presence of residual soil P that was either partially irreversible or very slowly desorbable in water.
Determination and Analysis of Nutritional Ingredient in Solanum nigrum Fruit

The nutritional substances in Solanum nigrum fruit were determined and investigated,including some minerals such as K,Na,Ca,Mg,Cu,Zn,Fe,Mn,and vitamins,amino acid,water,protein,starch,crude fiber,pectin,ach,total sugar,reducing sugar,tannins,total acid.The results showed that nutritional ingredients were rich in S.nigrum fruit,which was a wild fruit resources with great value in exploitation and had great diet value.
Polymorphic phase study on nitrogen-doped TiO2 nanoparticles: effect on oxygen site occupancy, dye sensitized solar cells efficiency and hydrogen production

In this work we show that phase formation and oxygen substitution can be controlled by the source of nitrogen used during the synthesis of TiO2 nanoparticles. By performing a thorough study on the structure of the nanoparticles, the use of NH4+ or NO3− was found to influence not only the N-doping level but also the formation of the polymorphic phase. Structural and microstructural refinement obtained by XRD pattern and data processing performed by the Rietveld refinement revealed that TiO2 obtained with HNO3 presents ca. 98% of anatase and ca. 2% for rutile. Meanwhile TiO2 nanoparticles synthesized with NH4F and NH4Cl presents a single anatase phase with ca. 7.0% and 4.4% of nitrogen substitutional oxygen sites, respectively. The local structure of N-doped TiO2 around the Ti atoms was investigated by X-ray absorption spectroscopy. The XANES spectra show that N-doped TiO2 possesses a characteristic pre-edge of a single anatase structure. The coordination number decreased and the shrinking Ti–O bond distances are due to the N-doping in the TiO2 structure. The most efficient dye sensitized solar cell and the higher hydrogen production was obtained from the TiO2/NH4Cl, which was obtained as a single anatase phase with intermediary concentration of N substitutional oxygen sites.
Chemical constituents from Glycyrrhiza uralensis

Objective To study the chemical constituents from the roots of Glycyrrhiza uralensis.Methods The chemical constituents in ethyl acetate fraction of 70% ethanol extract from the roots of G.uralensis were isolated and purified by chromatography on silica gel,polyamide,MCI,ODS,Sephadex LH-20 columns,and RP-HPLC.The structures were identified on the basis of physicochemical properties and spectral data analyses.Results Fourteen compounds were isolated and identified as 3,7-dimethyl licoflavonol(1),gancaonin I(2),licocoumarone(3),8-methylretusin(4),2′-hydroxyisolupalbigenin(5),isovestitol(6),dehydroglyasperin D(7),glycyrin(8),glycyrol(9),echinatin(10),licochalcone B(11),isoangustone A(12),gancaonin G(13),and 5,7,4′-trihydroxy-6,8-diisoprenylisoflavone(14). Conclusion Compound 1 is a new compound,and compounds 2—7 are isolated from this plant for the first time.