Prospects For Commercial Application Research Articles

GLASSY MATERIALS AND LIGHT: PART 2

In this second part it will be discussed some photonic applications of glassy and glass ceramic thin films which can be used as planar waveguides. Some photonic applications require certain specifications of glass, which can be quantified by studying the nonlinear optical properties of the materials. Therefore, a brief introduction of these phenomena is discussed, as well as the use of femtosecond lasers to manipulate the composition or for the preparation of waveguides into glasses. Finally, the article will address a brief introduction on microstructured optical fibers and commercial application prospects for these devices.

Facile synthesis of N-rich carbon quantum dots by spontaneous polymerization and incision of solvents as efficient bioimaging probes and advanced electrocatalysts for oxygen reduction reaction.

In this study, uniform nitrogen-doped carbon quantum dots (N-CDs) were synthesized through a one-step solvothermal process of cyclic and nitrogen-rich solvents, such as N-methyl-2-pyrrolidone (NMP) and dimethyl-imidazolidinone (DMEU), under mild conditions. The products exhibited strong light blue fluorescence, good cell permeability and low cytotoxicity. Moreover, after a facile post-thermal treatment, it developed a lotus seedpod surface-like structure of seed-like N-CDs decorating on the surface of carbon layers with a high proportion of quaternary nitrogen moieties that exhibited excellent electrocatalytic activity and long-term durability towards the oxygen reduction reaction (ORR). The peak potential was -160 mV, which was comparable to or even lower than commercial Pt/C catalysts. Therefore, this study provides an alternative facile approach to the synthesis of versatile carbon quantum dots (CDs) with widespread commercial application prospects, not only as bioimaging probes but also as promising electrocatalysts for the metal-free ORR.

Ultra-thin and porous MoSe2 nanosheets: facile preparation and enhanced electrocatalytic activity towards the hydrogen evolution reaction.

In this study, ultra-thin and porous molybdenum selenide (MoSe2) nanosheets were prepared through a modified liquid exfoliation method as efficient electrocatalysts for the hydrogen evolution reaction (HER). This novel structure enables the exposure of more catalytically active sites and moreover maintains effective electron transport, resulting in a small peak potential of ∼75 mV as well as long-term durability. In addition, due to the facile and economical preparation method as well as its eco-friendly synthetic conditions, this study provides a high-performance HER catalyst with promising commercial application prospects.

A Review of Destructive and Non-destructive Methods for Determining Avocado Fruit Maturity

Optimum harvest maturity is one of the important factors determining the quality of avocado fruit. Currently, avocado harvest maturity is mostly determined using markers or indices such as mesocarp oil, dry matter, or moisture content, all quantified destructively using representative samples of a batch in a consignment. Although useful, destructive techniques are time-consuming and results reflect properties of specific produce evaluated. High variation in maturity stages affect postharvest quality and the rate of ripening within a consignment, causing logistical difficulties. Emerging analytical techniques have particular advantages in non-destructive detection of food quality and safety. In this paper, destructive and non-destructive analytical methods and instruments for determining maturity parameters of avocado fruit are discussed. This review also looks at the trends in applying emerging optical and imaging techniques to the analysis of avocado fruit maturity and quality, in particular, visible to near infrared spectroscopy, ultrasonic system, ultrasound imaging, hyperspectral imaging, magnetic resonance imaging, and fluorescence imaging. On the basis of the observed trends, the technical challenges and future prospects for commercial application of these non-destructive techniques for maturity determination of individual avocado fruit are presented.

锂离子电池三元正极材料的研究进展

As the most promising commercial lithium-ion battery, the ternary transition metal oxides Li(Ni,Co,Mn)O2 have been widespread concerned by researchers and companies in recent years. They are expected to become a series of major cathode active material for EV batteries. The latest research progress on Li(Ni,Co,Mn)O2 is reviewed in terms of synthetic methods, property modifications and suitable electrolyte functional additives. Finally, its commercial application prospects are discussed and evaluated.

Isomerization of n-butane over Pd–SO4/ZrO2 catalyst: Prospects for commercial application

Increase in productivity of the refineries and improvement the fuel quality demands to engage isobutane as a key feedstock for producing both alkylates and oxygenated additives. Substantial growth of isobutane output via isomerization of n-butane poses a real technological challenge. The goal of this study is to investigate performance of Pd promoted sulfated zirconia catalysts (Pd–SZ) in n-butane isomerization. The physical–chemical characteristics of various anion-modified zirconia catalysts (XRD and IR spectra, BET surface) are presented. It was observed that Lewis acid sites of medium and strong strength and two types of Brönsted acid sites exist. Approximately 90–97% of zirconia is in tetragonal phase.The influence of parameters on conversion of n-butane and selectivity towards isobutane was investigated by varying the temperature (90–290°C), pressure (15–26bar), WHSV (0.5–5h−1), and molar ratio H2/C4 (0.08–3). Mainly, temperature and H2/C4 ratio are responsible for increasing the effectiveness of the process. At H2/С4=0.08–0.3 the apparent activity of Pd–SZ catalyst was high enough to reach the equilibrium conversion of n-butane to isobutane at 140°С value, that is, ∼65%. The best results were obtained on Pd–SZ granules in the form of 2mm trilobe. Water impact and the catalyst lifetime were studied in the pilot setup. Endurance testing of Pd–SZ catalyst in course of 90h showed its sustained operation at H2O concentration up to 20ppm without loss of activity.The estimated process specifications on Pd–SZ catalyst were compared to a conventional process; potential benefits of making use Pd–SZ catalyst are emphasized and discussed.

Colloidal Branched Semiconductor Nanocrystals: State of the Art and Perspectives

Colloidal inorganic nanocrystals are versatile nanoscale building blocks. Advances in their synthesis have yielded nanocrystals with various morphologies including spheres, polyhedra, rods, disks, sheets, wires, and a wide range of branched shapes. Recent developments in chemical methods have allowed the synthesis of colloidal nanocrystals made of sections of different inorganic materials connected together. Many research groups are investigating these nanocrystals' structural and photophysical properties experimentally and theoretically, and many have examined their prospects for commercial applications. Branched nanocrystals, in particular, are gaining attention, in part for their potential applications in solar cells or electronic devices. In this Account, we review recent developments in synthesis and controlled assembly of colloidal branched nanocrystals. Synthesis of branched nanocrystals builds on previous work with spherical nanocrystals and nanorods, but a unique factor is the need to control the branching event. Multiple arms can branch from a nucleus, or secondary branches can form from a growing arm. Branching can be governed by mechanisms including twinning, crystal splitting, polymorphism, oriented attachment, and others. One of the most relevant parameters is the choice of appropriate surfactant molecules, which can bind selectively to certain crystal facets or can even promote specific crystallographic phases during nucleation and growth. Also, seeded growth approaches recently have allowed great progress in the synthesis of nanocrystals with elaborate shapes. In this approach, nanocrystals with a specified chemical composition, size, shape, crystalline habit, and phase act as seeds on which multiple branches of a second material nucleate and grow. These approaches yield nanostructures with improved homogeneity in distribution of branch length and cross section. Ion exchange reactions allow further manipulation of branched nanocrystals by transforming crystals of one material into crystals with the same size, shape, and anion sublattice but with a new cation. Combining seeded growth with ion exchange provides a method for greatly expanding the library of branched nanocrystals. Assembly of morphologically complex nanocrystals is evolving in parallel to developments in chemical synthesis. While researchers have made many advances in the past decade in controlled assembly of nanocrystals with simple polyhedral shapes, modeling and experimental realization of ordered superstructures of branched nanocrystals are still in their infancy. In the only case of ordered superstructure reported so far, the assembly proceeds by steps in a hierarchical fashion, in analogy to several examples of assembly found in nature. Meanwhile, disordered assemblies of branched nanocrystals are also interesting and may find applications in various fields.

Improved biochemical characteristics of crosslinked β-glucosidase on nanoporous silica foams

Large mesoporous cellular foam (LMCF) materials were synthesized using the microemulsion templating route. For the enzyme stabilization, β-glucosidase was immobilized onto mesocellular silica foams (MCFs) in a simple and effective way, a process achieved using enzyme adsorption followed by glutaraldehyde (GA) crosslinking. This resulted in the formation of crosslinked enzyme aggregates (CLEAs) of nanometer scale. The structural and chemical properties of these prepared materials were characterized by TG, CPMAS NMR and nitrogen adsorption measurements. The crosslinked immobilizates retained activity over wider ranges of temperature and pH than those of the free enzyme. Kinetic parameter (Km) of the immobilized β-glucosidase is lower than that of its free counterpart. The resulting CLEA was proved to be active and recyclable up to 10 cycles without much loss in activity. This demonstrates its prospects for commercial applications. The immobilizate exhibited enhanced storage stability characteristics than the native enzyme. In contrast to adsorbed GL and covalently bound glucosidase, the resulting crosslinked enzyme aggregates (CLEAs) showed an impressive stability with high enzyme loadings.

Study on Micro-Grid Operating Mode Based on Game Theory

By describing the characteristics and the prospects of commercial application of current micro-grid, this paper analyzed the possible investors, operation subject and main users of micro-grid, and built the corresponding operating modes on this basis. Furthermore, based on the existing national policies and power grid management policies, this paper conducted an analysis of the feasibility and reliability of every operating mode and worked out several operating modes which are in line with regulations of our country and at the same time ensure the security of power grid.

Optical and Mechanical Properties of Transparent Conductive Al-Doped ZnO Films Deposited by the Sputtering Method

Al-doped ZnO transparent conductive oxide thin films (AZO) are prepared by the magnetron sputtering method. The structural, optical and mechanical properties of the AZO films are studied systematically. The average haze of the AZO sample is increased from 0.34% to 23.6% through wet etching treatment between 380 and 1100 nm, and the etched AZO sample has a higher average transmittance of about 82.3% in infrared wavelength range from 760 to 1100 nm due to the reduction of absorption by carriers. The average hardness and elastic modulus of the as-deposited AZO films, as determined using the nanoindentation technique, are approximately 10.2 GPa and 130 GPa, respectively. The critical fracture load related to the adhesion strength is about 91 mN. The optimized optical and electrical properties and referable mechanical data indicate that AZO films have good prospects for commercial applications.

Effect of Formic Acid on Conversion of Fructose to 5-Hydroxymethylfurfural in Aqueous/Butanol Media

Acid-catalyzed dehydration of carbohydrates into 5-hydroxymethylfurfural (HMF), a valuable biomass-derived intermediate, has received increasing attention. Efficient methods for HMF production are needed for successful commercialization of HMF in the near future. A new process for the dehydration of sugars into 5-hydroxymethylfurfural in aqueous/butanol media enhanced by using formic acid was developed. The effects of formic acid concentration, reaction temperature, and reaction time on the fructose conversion and HMF yield showed the significant influences of these process variables. The optimum conditions were found to be 2.5 mol/L formic acid concentration, 170°C and 70 min. Under such conditions, a fructose conversion of 98.3% with a HMF yield of 69.2% was achieved. The application of the butanol solvent and formic acid led to the conversion of fructose to HMF with high yield. The catalytic system in this study has prospects for commercial application due to its less corrosion and convenient downstream separation.

Covalent immobilization of β-1,4-glucosidase from Agaricus arvensis onto functionalized silicon oxide nanoparticles

An efficient β-1,4-glucosidase (BGL) secreting strain, Agaricus arvensis, was isolated and identified. The relative molecular weight of the purified A. arvensis BGL was 98 kDa, as determined by sodium dodecylsulfate polyacrylamide gel electrophoresis, or 780 kDa by size exclusion chromatography, indicating that the enzyme is an octamer. Using a crude enzyme preparation, A. arvensis BGL was covalently immobilized onto functionalized silicon oxide nanoparticles with an immobilization efficiency of 158%. The apparent V (max) (k (cat)) values of free and immobilized BGL under standard assay conditions were 3,028 U mg protein(-1) (4,945 s(-1)) and 3,347 U mg protein(-1) (5,466 s(-1)), respectively. The immobilized BGL showed a higher optimum temperature and improved thermostability as compared to the free enzyme. The half-life at 65 °C showed a 288-fold improvement over the free BGL. After 25 cycles, the immobilized enzyme still retained 95% of the original activity, thus demonstrating its prospects for commercial applications. High specific activity, high immobilization efficiency, improved stability, and reusability of A. arvensis BGL make this enzyme of potential interest in a number of industrial applications.

High thermoelectric performance BiSbTe alloy with unique low-dimensional structure

We report a detailed description of an innovative route of a melt spinning (MS) technique combined with a subsequent spark plasma sintering process in order to obtain high performance p-type Bi0.52Sb1.48Te3 bulk material, which possesses a unique low-dimensional structure. The unique structure consists of an amorphous structure, 5–15 nm fine nanocrystalline regions, and coherent interfaces between the resulting nanocrystalline regions. Measurements of the thermopower, electrical conductivity, and thermal conductivity have been performed over a range of temperature of 300–400 K. We found that MS technique can give us considerable control over the resulting nanostructure with good thermal stability during the temperature range of 300–400 K and this unique structure can effectively adjust the transport of phonons and electrons, in a manner such that it is beneficial to the overall thermoelectric performance of the material, primarily a reduction in the lattice thermal conductivity. Subsequently, this results in a maximum figure of merit ZT value of 1.56 at 300 K for p-type Bi0.52Sb1.48Te3 bulk material. This ZT value is over a 50% improvement of that of the state of the art commercial Bi2Te3 materials. We also report results of thermal cycling of this material for over one hundred cycles between 300–400 K. Our work offers an innovative route for developing high performance bismuth telluride based alloys and devices, which have even broader prospects for commercial applications. This technique may also be applicable to other thermoelectric materials.

Encapsulation of in vitro-derived explants of olive ( Olea europaea L. cv. Moraiolo) : II. Effects of storage on capsule and derived shoots performance

The experiments described in this paper were designed to examine the effect of storage at different temperatures for various periods on regrowth and proliferation ability of encapsulated olive microcuttings (capsules). The proliferation and rooting ability of the shoots derived from the capsules were compared with those maintained in normal proliferation by 45 days period of subculturing. A simple method of encapsulated microcuttings storage in plastic cuvettes was used. Interesting feature was the ability of the capsules to retain their viability and regrowth after storage at room temperature as well as at 4 °C for 15 and 30 days and both axillary buds on the nodes of almost all capsules sprouted successfully. Improvement in proliferation and rooting abilities were found in subsequent culturing of the shoots developed from the capsules. The study indicates bright prospects of commercial application of alginate nutrient capsule technology in various situations like supply of certified plant material from both official or private organizations to the plant nurseries and/or exchange of germplasm at international level without refrigerated containers just in plastic cuvettes.

Arthrobacter sp. lipase immobilization for improvement in stability and enantioselectivity

Arthrobacter sp. lipase (ABL, MTCC no. 5125) is being recognized as an efficient enzyme for the resolution of drugs and their intermediates. The immobilization of ABL on various matrices for its enantioselectivity, stability, and reusability has been studied. Immobilization by covalent bonding on sepharose and silica afforded a maximum of 380 and 40 IU/g activity, respectively, whereas sol-gel entrapment provided a maximum of 150 IU/g activity in dry powder. The immobilized enzyme displayed excellent stability in the pH range of 4-10 and even at higher temperature, i.e., 50-60 degrees C, compared to free enzyme, which is unstable under extreme conditions. The resolution of racemic auxiliaries like 1-phenyl ethanol and an intermediate of antidepressant drug fluoxetine, i.e., ethyl 3-hydroxy-3-phenylpropanoate alkyl acylates, provided exclusively R-(+) products ( approximately 99% ee, E=646 and 473), compared to cell free extract/whole cells which gave a product with approximately 96% ee (E=106 and 150). The repeated use (ten times) of covalently immobilized and entrapped ABL resulted in no loss in activity, thus demonstrating its prospects for commercial applications.

Thermal Upgrading of Fischer−Tropsch Olefins

Thermal oligomerization is a radical based conversion process. It offers specific advantages to linear olefinic feed with a high α-olefin content, like primary Fischer−Tropsch products. Thermal oligomerization of C4−C14 Fischer−Tropsch feed materials has been investigated over the temperature range 320−400 °C. Motor gasoline, distillate, and lubricating oil quality was determined by the feed used, and operating conditions had only a minor influence. Good quality distillate (cetane ≥ 54) and lubricating oil (viscosity index of 100) could be produced, while the naphtha was suitable for chemical applications, like plasticizer alcohols production. Oxygenates present in the Fischer−Tropsch product had little influence on the process. Carbon formation was about 400 μg·g-1. Prospects for commercial application was discussed and is limited to an olefin-rich refining environment, where feed-specific advantages can be used to offset the disadvantage of a slow reaction rate (0.1 mol·s-1·m-3).

Broad prospects for commercial application of the ultrasonic (cavitation) melt treatment of light alloys

Theoretical and applied aspects of ultrasonic melt treatment are considered. Industrial applications of the cavitation treatment for degassing, filtration, and grain refinement are illustrated using data for commercial alloys. Some new fields of use such as semi-solid processing, low-friction alloys, and natural composites are discussed. In general, wide prospects of commercial application for the ultrasonic melt treatment of light alloys are shown.

Economic losses and decontamination.

Mycotoxin contamination of crops may cause economic losses at all levels of food and feed production including crop and animal production, and crop distribution and processing. The national economy would be affected adversely by losses incurred by crop and livestock producers and the multiplier effect this has on other industries as a result of the reduced spending power of producers. Costs of chemical analyses, quality control and regulatory programs, research and development, extension services, law suits, and the cost of human illnesses must all be borne by the national economy. The value of the losses encountered depends on grain, animal, and animal product prices, interest rates, degree of contamination, and other economic variables. Even during favourable seasons it is likely that millions of dollars are lost as a result of the contamination of crops with mycotoxins. Many compounds and treatments have been tested in order to reduce mycotoxin concentrations in food and feed or to alleviate their adverse effects on animals. Some of these treatments show promising prospects for commercial application, while others have had commercial applications already. However, until reliable, cost-effective, commercially applicable methods are more widely available, problems associated with mycotoxin contamination and the economic losses resulting, will continue to be seen in food and agriculture industries.

Determination of Oil Saturation After Waterflooding in an Oil-Wet Reservoir The North Burbank Unit, Tract 97 Project

Laboratory and field techniques for measuring oil saturation were applied to an oil-wet reservoir. Log-inject-log and core measurements confirmed a 3.1 saturation exponent. Ultimate residual oil saturations determined by log-inject-log, core analysis, and microlaterolog procedures using laboratory-determined cementation and saturation exponents were in good agreement. Introduction In evaluating the prospects for commercial application of enhanced recovery processes, one of the most important factors to be considered is the quantity and distribution of oil present in the pore space at the time the process is to be applied. Waterflooding tends to leave low oil saturations in high-permeability zones and high saturations in tighter zones. Where expensive processes are to be applied, it is vital that the oil saturation distribution be established as accurately as possible. We have avoided the term "residual oil" because it is not precisely defined in the literature. Instead, the term "ultimate residual" is used to describe thoroughly flushed sand near the end-point of the relative permeability curve, and "current oil saturation" refers to the oil permeability curve, and "current oil saturation" refers to the oil saturation at some defined point in the production history of a reservoir. It is difficult to determine the oil saturation in a waterflooded reservoir for tertiary recovery purposes because there is some mobile oil present and significant changes can occur during drilling or coring. During the past few years, the rapid expansion of field testing of past few years, the rapid expansion of field testing of tertiary recovery processes using expensive chemical fluids has accentuated the importance of upgrading the accuracy of determination of oil saturation after secondary recovery. The industry has responded with several useful techniques, including special coring, logging, and tracer procedures. A number of excellent papers have been published giving details of these methods. This paper reports on the application of several techniques to a paper reports on the application of several techniques to a strongly oil-wet reservoir - the North Burbank Unit Tract 97 area. Nature of the Reservoir The North Burbank reservoir, which lies at a depth of about 3,000 ft, is a relatively clean, well consolidated sandstone of a type that occurs in many fields of north-eastern Oklahoma. The sand averages 47.2-ft net thickness, 16.8-percent porosity, and 50-md permeability. The stock-tank oil has a gravity of 39 degrees API. Tract 97, where the tertiary pilot is being run, is one of the most homogeneous areas of the North Burbank field. There are frequent, thin, shale laminae, but these do not interfere markedly with vertical fluid movement. Dispersed shales occur occasionally in the sand column, but water-sensitive clays have not been observed in the North Burbank reservoir. It long has been known that the North Burbank reservoir is strongly oil-wet. During the development of the waterflood, at least two wells on each quarter section were cored and, at frequent intervals, a wettability index designated as the Amott-Harvey "relative displacement index" has been run. This technique, which is similar to the Amott wettability measurement, compares the tendency of a permeability plug at irreducible oil to imbibe oil with the tendency of the same plug at irreducible water to imbibe water. The results are expressed as numbers ranging from − 1.0 (oil-wet) to + 1.0 (water-wet). Details of the procedure are given in Ref. 8. There is always some variation from specimen to specimen within a well, and from well to well, but the average over the North Burbank Unit is -0.7, strongly oil-wet. JPT P. 491