Miracle-dz/UniFAR-FTUs huggingface dataset:
Solar reforming applications study summary

Research in recent years has demonstrated the efficient use of solar thermal energy for driving endothermic chemical reforming reactions in which hydrocarbons are reacted to form syngas. Closed-loop reforming/methanation systems can be used for storage and transport of process heat and for short-term storage for peaking power generation. Open-loop reforming and gasification systems can be used for direct fuel production; for production of syngas feedstock for further processing to bulk ammonia, hydrogen, and liquid fuels; and for destruction of hazardous organic materials. To help identify the most promising areas for future development of this technology, we discuss in this paper the market potential of these applications.
Preparation of high-purity γ-Mn3O4 by decomposing MnCO3 from low-grade rhodochrosite ore

High-purity Mn3O4 was prepared from low-grade rhodochrosite ore (LGRO). The Mn recovery efficiency was more than 97% with the blended precipitant of Na2CO3 and NH4HCO3 (1∶1 mol mol−1). The total Mn content (TMC) of product increased with increase of decomposition time and temperature. The quantitative relationship between TMC and decomposition time as well as decompositions temperature could be fitted by empirical formulae. When decomposing MnCO3 at 1323 K for 120 min, the TMC of Mn3O4 could reach 72·01%, which was larger than that of the premium grade of mangano-manganic oxide for preparing soft magnetic ferrites. The product was investigated by XRD, FTIR and SEM. SEM images revealed that the product consisted of small and uniform particles with smooth surface and good dispersion. Through XRD, FTIR and determination of TMC, the as-prepared product was confirmed to be high-purity γ-Mn3O4. The ionic distributions were formulated as [Mn2+][Mn2+ 0·3024Mn3+ 0·2937 Mn4+ 0·3786 □0·0254]2O4.
DNA Wrapped Metallic Single-walled Carbon Nanotube Sensor for Pb (II) Detection

Based on the interaction of Pb (II) ions with nucleic acid via phosphate groups and nucleic bases of the deoxyribonucleic acid structure, an electrochemical sensor with DNA wrapped metallic single-walled carbon nanotube (SWNT) has been fabricated for sensitive and selective detection of lead ion (Pb2+). The sensor shows a rapid differential pulse voltammetry signal response to the content of Pb2+, and a quantitative detection of Pb2+ has been established with an expanded linear responsive range from 1 × 10−9 to 1.0 × 10−8 mol L−1 (R = 0.9979) and a detection limit of 4.1 × 10−10 mol L−1 in buffer solution (pH 5.0). Furthermore, the sensor displayed a negligible differential pulse voltammetry signal response for other metal ions, indicating its high selectivity for Pb2+. The investigation of electrochemical impedance spectroscopy and cyclic voltammetry in buffer solution demonstrated that metallic SWNTs played an important role in enlarging current response and increasing sensitivity of the sensor.
DISTRIBUTION OF AFLATOXIN IN PISTACHIOS. 2. DISTRIBUTION IN FRESHLY HARVESTED PISTACHIOS

The aflatoxin sample probability distribution {P i (n)} (fraction of samples exhibiting aflatoxin concentrations in ranges of log C) for field-run and for finished pistachios was calculated for several crop years since 1980, using orchard, survey, and certification data from assorted sources. Sample size n was 100 nuts for one year, 3200 nuts for the remainder. The [single-nut] crop probability distributions {p i , c i } were derived using the methods described in Schatzki (J. Agric. Food Chem. 1995, 43, 1561), where p i is the probability of a single nut having concentration c i . The {p i , c i } distributions of field-run material were found to be consistent, but with some evidence of a decrease at the highest aflatoxin concentrations during 1981-1991. As a result, the average aflatoxin concentration in U.S. crops appears to have decreased from about 10 to 1.5 ng/g in that period. In finished pistachios the predicted {p i } distribution of contaminated nuts was found to be 2-4-fold lower in the crop years for which both field-run and finished data were available, suggesting that sorting for quality removes a large part of the aflatoxin present at harvest.
Polyhydroxyalkanoates, a family of natural polymers, and their applications in drug delivery

Polyhydroxyalkanoates (PHAs) are natural biopolymers produced by various microorganisms as a reserve of carbon and energy. PHA synthesis generally occurs during fermentation under nutrient limiting conditions with excess carbon. There are two main types of PHAs, short chain length PHAs (scl-PHAs) and medium chain length PHAs (mcl-PHAs). The mechanical and thermal properties of PHAs depend mainly on the number of carbons in the monomer unit and its molecular weight. PHAs are promising materials for biomedical applications because they are biodegradable, non-toxic and biocompatible. The large range of PHAs, along with their varying physical properties and high biocompatibility, make them highly attractive biomaterials for use in drug delivery. They can be used to produce tablets, micro- and nanoparticles as well as drug eluting scaffolds. A large range of different PHAs have been explored and the results obtained suggest that PHAs are excellent candidates for controlled and targeted drug delivery systems. © 2015 Society of Chemical Industry
Investigation of liquid ethanol evaporation and combustion in air and oxygen environments inside a 25 kW vertical reactor

The combustion characteristics of liquid ethanol in air and oxygen–carbon dioxide environments are investigated numerically inside a vertical reactor. Gambit 2.2 was used to construct the mesh and Fluent 12.1 was used to perform the calculations. Different oxidizer environments were considered including pure air, oxygen-enriched air, in addition to the cases of OF21 (21% O2 and 79% CO2) and OF29 (29% O2 and 71% CO2). Comparisons were performed between the different cases and the results were validated against wide range of the experimental data. Nonpremixed combustion model which utilizes probability density function to predict the scalar quantities was incorporated to simulate the combustion process. Two turbulence models, realizable k–ɛ (RKE) model and Reynolds stress model (RSM), were applied and their results were compared. The Euler–Lagrange approach was utilized to solve the discrete phase model. The results showed the ability of the RKE model to predict much closer data to the experimental data than the RSM which over predicts the temperature. For the case of OF21, the flame was lifted and the combustion temperature was reduced as compared to the air combustion case. However, the OF29 combustion case resulted in a very close performance to the case of air combustion.
Latitudinal and diurnal variations of some important atomic oxygen dayglow emissions

In the present paper the latitudinal and diurnal variations of 5577 A, 6300 A, 7320 A and 8446 A dayglow emissions are presented. The volume emission rate profiles for these emissions are calculated using updated Glow model. To test the model, the calculated emission rate profiles for 5577 A and 6300 A are compared with the measurements of Wind Imaging Interferometer (WINDII) for which data are available. The emission intensities have been studied on 15 Jan. 1995 and 15 June 1995 using Tobiska solar EUV flux model. These calculations show that the intensity is maximum at 1200 hrs LT for both the dates at all latitudes for 5577 A and 8446 A emissions. The position of maximum intensity is found to be variable for 6300 A emission on 15 January. At 30oN latitude, the peak is found at 1000 hrs LT, while at 5oN and 45oN the maximum intensity is found to occur at nearly 1200 hrs LT. On 15 June, the intensity of 6300 A emission does not show any pronounced peak and emission is found to vary within 15% between 0800 and 1400 hrs LT. On 15 January, the 7320A emission shows that the peak of maximum intensity occurs at nearly 1200 hrs LT at 5oN, which moves quite close to 1000 hrs LT at 30oN and 45oN latitudes. On the other hand, the peak of maximum intensity for 7320 A emission is found between 1200 hrs and 1400 hrs LT at all latitudes on 15 June. The smooth variation in 8446 A intensity may be attributed due to steadiness of photoelectron fluxes at higher energies.
Extraction of 4‐Hydroxycinnamic Acid from Aqueous Solution by Emulsion Liquid Membranes

Abstract This work reports a study of 4‐hydroxycinnamic acid extraction by emulsion liquid membranes. The effect of the presence of additives in the membrane phase on solute permeation was tested. The membrane with 2 wt. % of isodecanol, 2 wt. % of ECA4360J, and Shellsol T as diluent was selected to examine the permeation of 4‐hydroxycinnamic acid. The modeling of solute extraction was done by taking into account the mass transfer in the external phase and globule, and the reaction between the diffusing component and the stripping reagent. The agreement between the calculated results and the experimental data was found satisfactory.
Highly heterogeneous Ty3/Gypsy -like retrotransposon sequences in the genome of cassava ( Manihot esculenta Crantz )

The use of PCR has enabled the survey of transposable elements in many plants; thereby making the study of their diversity and applications possible in species where the full genome sequence data are not yet available. In the present study, we used PCR primers anchored on the conserved domain of reverse transcriptase and endonuclease to amplify the Ty3/Gypsy -like polyprotein fragment from the genome of cassava ( Manihot esculenta Crantz ). The PCR product was cloned and sequenced. Sequence analysis of individual clones clearly identified the conserved domain of the polyprotein enzymes and showed the cassava Ty3/Gypsy -like retrotransposon, Megyp (for Manihot esculenta gypsy-like), sequences to be highly heterogeneous. Some Megyps clustered with other plants’ Ty3/Gyps y-like retrotransposons, while some clustered with Gypsy of Drosophila melanogaster and Ty3-2 of Saccharomyces cerevisia e in the comparative multiple sequence analysis. This suggests that the later belong to the retrovirus lineage of this group of elements. Southern analysis showed that, the Megyps and analogues were highly repeated within the genomes of cassava cultivars. Key words: Cassava, transposable-elements, retrotransposons, retroviruses, Manihot esculenta, Ty3/Gypsy.
Influence of Humidity on Adsorption Capacity from the Wheeler-Jonas Model for Prediction of Breakthrough Times of Water Immiscible Organic Vapors on Activated Carbon Beds

The Wheeler-Jonas model is well known for its good prediction of breakthrough times for organic vapors on activated carbon beds. However, in its original form it is only valid under dry conditions: no prewetting of the filter and no humidity in the ambient air during use. The main parameter in the Wheeler-Jonas equation is the adsorption capacity, We. By measuring over 200 breakthrough times, with 7 different vapors on 3 different types of activated carbon, a satisfactory model for the influence of moisture on We was established. The only supplementary information needed, compared with the application of the Wheeler-Jonas equation under dry circumstances, is the water isotherm of the activated carbon.
Modification of amylose with diketene

This work deals with the modification reaction of amylose with diketene using tertiary amines as catalysts. The structure of the resulting polymers was determined by means of IR, 1H and 13C NMR spectroscopy as well as by chemical analysis. A linear dependence of the reaction rate on polymer, diketene and pyridine concentrations was found. The activation energy was found to be 27,2 kJ/mol (6,5 kcal/mol). Polymeric chelates between partially modified amylose and cupric ions (Cu2+) were prepared. However, not all of the β-keto ester groups in the partially modified amylose participate in binding the cupric ions.
Temperature- and Frequency-Dependent Optical Constants for Nitric Acid Dihydrate from Aerosol Spectroscopy

Frequency-dependent complex refractive indices have been determined from the aerosol infrared extinction spectra of laboratory-generated nitric acid dihydrate (NAD) particles. The spectra reported here were recorded at several temperatures (160, 180, and 190 K) over the mid-infrared region of the spectrum (700−4700 cm-1). The optical constants retrieved from these spectra are overall in reasonable agreement with results from thin-film experiments conducted at 184 K, although there are significant differences in the intensities of several absorption bands located below 1500 cm-1. We attribute these to the different methods used to make the samples in the two types of experiments and consider the substrate-free aerosol results to be unperturbed NAD. The temperature dependence of the NAD aerosol optical constants was found to be quite weak between 160 and 190 K, in contrast to the strong temperature dependence observed previously for the optical constants of water ice.
Study on Water-Atmosphere Interface Distribution and Concentration Fluctuation Intensities of Polybrominated Diphenyl Ethers in Great Lake

In this study, the water-atmosphere interfaces distribution and concentration fluctuation intensities of polybrominated diphenyl ethers (PBDEs) in Great Lake were analyzed. Based on the selected significant quantum descriptors, bromination pattern descriptors ( N PBS ) and temperature descriptors by combination of variable important for projection (VIP) and correlation analysis, 35 experimental Henry’s law constants of PBDEs (transformed as lg H , represented the water-atmosphere interfaces distribution) at different temperatures were divided into modeling set (25 samples) and testing set (10 samples) to establish the quantitative structure-parameter relationship (QSPR) model for lg H at different temperatures via the optimal subset method firstly. Then, the Henry’s law constants of other unknown PBDEs at different temperatures were predicted and the water-atmosphere interfaces distribution regularity were analyzed from views of chemical quantum descriptors and substituent pattern respectively. At last, the concentration fluctuation intensities in Great Lake were discussed based on the correlation analysis between the detected concentration data and experimental Henry’s law constants. The established optimal QSPR model has shown a good fitness and predictive ability for Henry’ law constants of PBDEs, with the R 2 and R 2 pred of 0.985 and 0.978 respectively. From the view of chemical quantum descriptors, the lg H of PBDEs is positive correlative with E HOMO , indicating the ability to provide electron of congener molecule has played a leading role in governing the exchange ability between water-atmosphere interface; from the view of bromination pattern, both number of relative positions and each position have great influence on the water-atmosphere interface distribution, especially N 2(6) and N o can decrease the release of PBDEs from water to atmosphere in Great Lake. The concentration fluctuation intensity is negative correlated with the lg H linearly, the bigger solubility of congener in Great Lake, and the stronger water-atmosphere interface exchange ability and fluctuation intensity.
Adjustment of Clays to Chemical Change and the Concept of the Equivalence Level

Further x-ray and chemical work on suspended sediment samples and cored samples from the James River and its estuary support earlier proposals by the author. A chlorite-like clay is forming from weathered illite through a mixed-layer illite—vermiculite-chlorite stage, and some illite is seemingly regenerated to a better illite by potassium fixation. Chemical analyses of interstitial water, hydrochloric acid-leachate, and fused samples offer explanations regarding the chemical changes occurring in clays as composition of the environment changes. Magnesium is adsorbed by clays to a far greater degree than potassium in the marine and brackish environment. The variance between clays found in Recent and ancient sediments is related to and explained by the concept of the equivalence level. It is suggested that K+ is adsorbed preferentially to Mg2+ by clays when they have been buried to a depth that is greater than that of the Mg2+ — K+ — equivalence level; above this level Mg2+ is preferentially adsorbed by the clays. The trifold nature of clay minerals in terms of their origin and distribution is briefly discussed.
Effects of stress on the stability of x‐ray masks

Accurate reproduction and overlay of submicron features with x‐ray lithography puts very stringent requirements on the mask. The stability, flatness, and durability of the mask depend on, among other factors, the stress of the blank membrane and the total stress of the overlaying films. Stress is monitored using three different techniques. Metal absorber stress σm=0.1×109 dyn/cm2 or less with membrane stress σBN∼10 σm is needed for masks with distortion less than 5 ppm. Long‐term stability of a boron nitride (BN) mask has been measured to be better than ±0.03 μm (1σ). Mask blanks with flatness <0.2 μm are routinely fabricated with high stress BN and flat glass. High durability membranes (E/1−ν=2.4×1012 dyn/cm2) with low defect counts (<1/cm2) make feasible direct metal deposition on BN and eliminate the use of polyimide.
Comparison among Slip-Link Simulations of Bidisperse Linear Polymer Melts

Recent simulations of entangled polymer dynamics are based on slip-link models pioneered by Hua and Schieber (J. Chem. Phys. 1998, 109, 10018). In this study, we compare different slip-link models in their prediction of the linear viscoelasticity of bidisperse linear polymers to examine how effectively such models account for constraint release. We compare the DT model by Doi and Takimoto (Philos. Trans. R. Soc. London, Ser. A 2003, 361, 641), the NS model by Nair and Schieber (Macromolecules 2006, 39, 3386), and the primitive chain network (PCN) model by Masubuchi et al. (J. Chem. Phys. 2001, 115, 4387). It is found that DT and PCN models are in better quantitative agreement with literature data than is the NS model. This indicates that renewal of entanglements along the chain due to constraint release, explicitly accounted for in DT and PCN, is not equivalent to spatial fluctuations of slip-links, as included in the NS mean field approach.
Assessment of PAHs in water and fish tissues from Great Bitter and El Temsah lakes, Suez Canal, as chemical markers of pollution sources

Sea water and fish tissue samples were collected from nine sampling stations from the Great Bitter and El Temsah lakes in the Suez Canal and analysed for polycyclic aromatic hydrocarbon (PAH). The compositions of PAH determined in the dissolved fraction of sea water were measured in order to use them as chemical markers for identifying different sources of PAH pollution in this region. PAHs determined in fish tissues were measured for comparison with human health standards as consumption. The total mean PAHs concentrations in the sea water samples ranged from 0.28 to 39.57 μg l−1 with an overall mean of 10.78 and 12.38 μg l−1 for El Temsah and Bitter Lakes water, respectively. Total PAHs fractions recorded in muscle tissues of all different Osteicthyes fishes collected from Great Bitter lakes ranged from 5.8 to 218.5 μg g−1 with an overall mean of 57.98 μg g−1 during all seasons. However, they ranged from 68 to 623 μg g−1 with an overall mean of 87.69 μg g−1 recorded in El Temsah lake during four seasons (2003–2004). Benzo(a)pyrene was the most dominant PAHs found in the sea water samples from both lakes with an average concentration of 3.8 μ g l−1. Dibenzo(a,h)anthracene (DBA) was the most dominant PAHs recorded in fish samples. A maximum of 533 μg g−1 of DBA was recorded in Dahbana sp. collected from Bitter lakes during January 2004. However, a maximum of 68.7 μ g g−1 was recorded in Liza carinata species collected from El Temsah lake during July, 2004. The simultaneous occurrence of isomer ratios PHE/ANT<10 for all stations indicated that the major PAH input to water was from combustion of fossil fuel (pyrolytic source). The average ratios were 1.21 and 12.9 during winter (January 2004) and 4.3 and 8.63 during spring (April 2004) for all water samples of Great Bitter lakes and El Temsah lake, respectively. In addition, the present data demonstrate that PAHs from fossil fuel sources (MW<178) were the least significant source of PAHs in this region.
Heavy metal levels in mussels (Unio stevenianus Krynicki) obtained from Van Lake.

The aim of this study was to evaluate heavy metal levels in mussels ( Unio stevenianus Krynicki) obtained from Van Lake. A total of 120 samples representing each of the four seasons was collected between 01.01. 1994 and 01.01. 1995. The organic parts of the samples were ashed with a mixture of magnesium oxide and magnesium nitrate according to the dry ashing method and arsenic residues were measured by silver diethyldithyocarbamate in UV spectrophotometer; copper, cadmium, zinc and lead levels were also determined using an atomic absorption spectrophotometer. In the analysis of the 120 samples for residues of heavy mettals, the average values were found to be: 1.43±0.81 ppm for lead, 0.09±0.02 ppm for cadmium, 5.83±0.73 ppm for copper, 15.93±3.26 ppm for zinc and 0.06±0.05 ppm for arsenic. Evaluation of the study results showed that these heavy metal levels were within the normal ranges for our country and other country's acceptable limits.
An Efficient Synthesis of Phenol via CuI/8-Hydroxyquinoline-Catalyzed Hydroxylation of Aryl Halides and Potassium Hydroxide

The CuI/8-hydroxyquinoline-catalyzed direct hydroxylation of aryl iodides with KOH takes place at 100 degrees C in a mixed solvent system (t-BuOH-DMSO-H2O), providing the corresponding phenols in great diversity. Aryl bromides are found to be rather less reactive under these reaction conditions.
Detailed Flow and Heat Transfer Coefficient Measurements in a Model of an Internal Cooling Geometry Employing Orthogonal Intersecting Channels

Cast interconnecting passage Lattice cooling geometries offer the gas turbine designer higher structural integrity and improved convective efficiency when compared to traditional aerofoil rear cooling strategies. In this paper, local heat transfer coefficient distributions were measured in a model of an idealised engine lattice cooling geometry, with flow ejection through film-cooling holes. The measurements were made using the transient liquid crystal technique in a large-scale perspex model at low temperature. The technique allows very high data resolution. Heat transfer patterns on all surfaces of the device including the internal web are presented at engine representative Reynolds numbers. The results are discussed in terms of the interpreted flow field. Furthermore, a subsequent analysis which accounted for the changing driving gas temperature and mass flow rate through the model has allowed the heat transfer coefficients to be derived based on the mixed bulk temperature, and local passage Reynolds number. © 2000 ASME