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Nicotiana tabacum leaves are mainly used in the production of cigarettes and cigars all over the world, and a large amount of waste materials will be produced in the process. High-value scopoletin can be extracted and separated from waste materials, but there are some problems, such as low purity of products and inability of large-scale production. In this study, we established an efficient and stable method for producing high-purity scopoletin from waste tobacco by containing acetone reflux extracting with dynamic axial compression-high performance liquid chromatography (DAC-HPLC) separating. In particular, the extraction system makes the scopoletin fully extracted through continuous reflux, the DAC-HPLC system makes the high-purity scopoletin repeatedly obtained, and the DAC-HPLC system was first used for scopoletin. Finally, related to the waste tobacco power, the yield of scopoletin is 1.9%, and its HPLC purity is 99.94%. Additionally, a preparation method for the colorless needle crystal of scopoletin was established. Meanwhile, it has a strong antioxidant activity by testing the scavenging activity of the DPPH free radical and the Fe3+ reducing power. And its spatial structure was identified by an X-ray diffractometer, which laid a good foundation for in-depth study of scopoletin. [ABSTRACT FROM AUTHOR]

Omega-3 fatty acids are in high demand due to their efficacy in treating hypertriglyceridemia and preventing cardiovascular diseases. However, the growth of the industry is hampered by low purity and insufficient productivity. This study aims to develop an efficient RP-MPLC purification method for omega-3 fatty acid ethyl esters with high purity and capacity. The results indicate that the AQ-C18 featuring polar end-capped silanol groups outperformed C18 and others in retention time and impurity separation. By injecting pure fish oil esters with a volume equivalent to a 1.25% bed volume on an AQ-C18 MPLC column using a binary isocratic methanol–water (90:10, v:v) mobile phase at 30 mL/min, optimal omega-3 fatty acid ethyl esters were obtained, with the notable purity of 90.34% and a recovery rate of 74.30%. The total content of EPA and DHA produced increased from 67.91% to 85.27%, meeting the acceptance criteria of no less than 84% set by the 2020 edition of the Pharmacopoeia of the People's Republic of China. In contrast, RP-MPLC significantly enhanced the production efficiency per unit output compared to RP-HPLC. This study demonstrates a pioneering approach to producing omega-3 fatty acid ethyl esters with high purity and of greater quantity using AQ-C18 RP-MPLC, showing this method's significant potential for use in industrial-scale manufacturing. [ABSTRACT FROM AUTHOR]

In recent years, molybdenum disulfide (MoS 2) has gained significant attention in the scientific community. Few-layered MoS 2 demonstrates unique properties and potential applications. However, the synthesis of few-layered and high-purity 1T-MoS 2 is still a challenge. In this study, we successfully employed a hydrothermal method to synthesize few-layered and high-purity 1T-MoS 2. The purity of the material is controlled by a combination of sodium borohydride and ethanol. Notably, the few-layered 1T-MoS 2 exhibits exceptional performance as a supercapacitor, including the high specific capacitance (250.3 ​F ​g−1 at a current density of 1 ​A ​g−1) and excellent long-trem cycling stability (90.7 ​% after 5000 cycles). Meanwhile, the asymmetric device assembled by 6-FL-1T-MoS 2 and active carbon on carbon cloths exhibits excellent flexibility and high energy and power density (23.1 ​μWh cm−2 at 600 ​μW ​cm−2, 55 ​μWh cm−2 at 12000 ​μW ​cm−2). This work provides valuable insights into the synthesis of few-layered and high-purity 1T-MoS 2 , opening up new avenues for further research and applications. [Display omitted] [ABSTRACT FROM AUTHOR]

The utilization of lithium slag (LS), a solid waste generated during the production of lithium carbonate, poses challenges due to its high sulfur content. This study presents a novel approach to enhancing the value of LS by employing alkali fusion and hydrothermal synthesis techniques to produce zeolite A at low temperatures. The synthesis of high-purity and crystalline lithium-slag-based zeolite A (LSZ) at 60 °C is reported for the first time in this research. The phase, morphology, particle size, and structure of LSZ were characterized by XRD, SEM, TEM, N2 adsorption, and UV Raman spectroscopy, respectively. High-purity and crystalline zeolite A was successfully obtained under hydrothermal conditions of 60 °C, an NaOH concentration of 2.0 mol/L, and a hydrothermal time of 8 h. The samples synthesized at 60 °C exhibited better controllability and almost no byproduct of sodalite occurred compared to zeolite A synthesized at room temperature or conventional temperature (approximately 90 °C). Additionally, the growth mechanism of LSZ was elucidated, challenging the traditional understanding of utilization of lithium and enabling the synthesis of various zeolites at lower temperatures. [ABSTRACT FROM AUTHOR]

The conventional method for synthesizing Ti 2 SC depends on the reaction between TiS and TiC, which requires the utilization of costly Ti, TiC, or TiS 2 powders. Utilizing TiO 2 as the raw material for the synthesis of Ti 2 SC enables the cost-effective preparation of this compound. However, the optimization of the TiO 2 /C/X n S m (sulfides) system is of utmost importance when aiming to synthesize Ti 2 SC through carbothermal-sulfurization of TiO 2 , as the formation temperature of TiS and TiC greatly depends on the X n S m. In this study, the identification of the thermodynamically dominant region for the formation of TiS and TiC in the TiO 2 /C/X n S m systems was conducted by utilizing various sulfides (63 types). Considering factors such as the challenges associated with removing by-products, accessibility, and toxicity, FeS 2 was ultimately chosen as a highly promising candidate. Thanks to the low melting point of FeS 2 , Ti 3 O 5 , the preliminary carbothermal reduction product of TiO 2 , has achieved rapid-deep deoxidation and phase reconstruction processes in the molten phase. Meanwhile, unlike the conventional solid-solid sintering reaction, which often results in residual reactants that are challenging to eliminate. This novel one-step phase transformation process that occurs in the molten phase exhibits minimal impurity phases, apart from the by-product Fe. Ti 2 SC with a purity greater than 99 wt% was obtained when the TiO 2 /C/FeS 2 was pickled to remove Fe after sintering at 1600 °C for 5 min. This work will provide the theoretical basis and a new path for the low-cost preparation of sulfur-containing MAX phases. [ABSTRACT FROM AUTHOR]

Omega-3 fatty acids are in high demand due to their efficacy in treating hypertriglyceridemia and preventing cardiovascular diseases. However, the growth of the industry is hampered by low purity and insufficient productivity. This study aims to develop an efficient RP-MPLC purification method for omega-3 fatty acid ethyl esters with high purity and capacity. The results indicate that the AQ-C18 featuring polar end-capped silanol groups outperformed C18 and others in retention time and impurity separation. By injecting pure fish oil esters with a volume equivalent to a 1.25% bed volume on an AQ-C18 MPLC column using a binary isocratic methanol–water (90:10, v:v) mobile phase at 30 mL/min, optimal omega-3 fatty acid ethyl esters were obtained, with the notable purity of 90.34% and a recovery rate of 74.30%. The total content of EPA and DHA produced increased from 67.91% to 85.27%, meeting the acceptance criteria of no less than 84% set by the 2020 edition of the Pharmacopoeia of the People’s Republic of China. In contrast, RP-MPLC significantly enhanced the production efficiency per unit output compared to RP-HPLC. This study demonstrates a pioneering approach to producing omega-3 fatty acid ethyl esters with high purity and of greater quantity using AQ-C18 RP-MPLC, showing this method’s significant potential for use in industrial-scale manufacturing.

In this study, the tendency of having different grain structures depending on the impurity levels in AZ91 alloys was investigated. Two types of AZ91 alloys were analyzed: commercial-purity AZ91 and high-purity AZ91. The average grain size of the commercial-purity AZ91 alloy and high-purity AZ91 is 320 µm and 90 µm, respectively. Thermal analysis revealed negligible undercooling in the high-purity AZ91 alloy, while undercooling of 1.3 °C was observed in the commercial-purity AZ91 alloy. A CS analyzer was employed to precisely analyze the carbon composition of both alloys. The carbon content of the high-purity AZ91 alloy was found to be 197 ppm, while the commercial-purity AZ91 alloy contained 104 ppm, indicating a difference of approximately 2 times. The higher carbon content in the high-purity AZ91 alloy is believed to be due to the use of high-purity pure Mg in its production (the carbon content of high-purity pure Mg is 251 ppm). To simulate the vacuum distillation process commonly used in the production of high-purity Mg ingots, experiments were conducted to investigate the reaction of carbon with oxygen to produce CO and CO2. XPS analysis and simulation results for activities confirmed the formation of CO and CO2 during the vacuum distillation process. It could be speculated that the carbon sources in the high-purity Mg ingot provide Al-C particles, which act as nucleants for Mg grains in the high-purity AZ91 alloy. Thus, it can be considered the main reason that high-purity AZ91 alloys have a finer grain structure than that of commercial-purity AZ91 alloys. [ABSTRACT FROM AUTHOR]

High-purity SiC ceramic devices are applied in semiconductor industry owing to their outstanding properties. Nevertheless, it is difficult to densify SiC ceramics without any sintering additive even by HP sintering. In this work, high-purity and dense SiC ceramics were fabricated by HP sintering with very low amounts of sintering aids. Residual B content was only 556 ppm and relative density was more than 99.5%. Furthermore, thermal conductivity of as-prepared SiC ceramics was improved from 155 W m−1 K−1 to 167 W m−1 K−1 by increasing holding time and their plasma corrosion resistance was promoted in the meantime. The as-prepared high-purity SiC ceramics have broad application prospects in the field of semiconductor industry. [ABSTRACT FROM AUTHOR]

The current study presents a novel method to prepare high-purity V2O5 from Na3VO4 solution. This process characterizes Na3VO4 calcification separation, Ca10V6O25 ammoniation and solubilization, NH4VO3 crystallization, and vanadium precipitation, which achieves elemental V migration from the Na3VO4–Ca10V6O25–NH4VO3–V2O5 phase, finally obtaining high-purity V2O5. The influencing factors of the preparation process were investigated, and the results showed that vanadium was released from Na3VO4 solution to synthesize Ca10V6O25 in the first stage under the most suitable conditions (Ca/V molar ratio of 1.8, and a concentration of NaOH less than 160 g/L). In the second stage, the leaching efficiency of vanadium reached 95% at optimal conditions (NH4+/V molar ratio was 1.2, reaction temperature and time were 90 °C and 30 min, respectively). In the third stage, NH4VO3 yield and crystal size reached maximum values under optimal conditions (feed rate, crystallization temperature, and the power factor of the circulating pump were 6 m3/h, 30 °C, and 80% respectively). Finally, high-purity V2O5 was prepared via a series of large particle NH4VO3 post-treatments. In addition, the ICP analysis confirmed that the purity of the generated V2O5 was more than 99.5%.

Vanadium, a crucial rare metal element, finds extensive applications across various fields owing to its exceptional physical and chemical properties. Its significance is further underscored by the increasing demand for vanadium-based applications, such as vanadium redox flow batteries, high-performance catalysts, and medical materials. Consequently, high-purity vanadium-based materials have emerged as an important direction, garnering widespread attention from academia to industry. In the preparation of high-purity vanadium-based materials, significant efforts have been made by researchers to enhance the extraction efficiency of vanadium. Nevertheless, given the complexity and diversity of vanadium-bearing resources, there remains a need to improve the purification effects of traditional extraction processes. Based on this situation, this paper provides a comprehensive overview of the production and consumption markets of vanadium to understand the necessity of developing high-purity vanadium-based materials. Subsequently, it introduces the typical processes for producing high-purity vanadium products from vanadium-bearing resources in detail. Among these processes, the purification step, which plays a crucial role in achieving high-purity vanadium-based materials, is thoroughly examined, accompanied by insights into some advanced short-route technologies. Finally, the common applications of high-purity vanadium-based materials are summarized. [Display omitted] [ABSTRACT FROM AUTHOR]

Hydrogen has received enormous attention as a clean fuel with its high specific energy (HHV=142 MJ kg -1 ). To apply hydrogen as a practically available energy vector, the direct production of high-pressure hydrogen with high purity is pivotal as it allows for circumventing the mechanical compression process. Recently, the concept of utilizing sodium borohydride (SBH) dehydrogenation as a chemical compressor that can generate high-pressure hydrogen gas was demonstrated by adopting formic acid as an acid catalyst. However, the presence of impurities (e.g., CO, CO 2 ) in the final gas product requires an alternative method to enhance the use of SBH as a chemical compressor. Here, we highlighted the feasibility of producing high-purity, high-pressure hydrogen gas from the SBH dehydrogenation with and without Co-based catalysts. The scrutiny behind the thermodynamics and kinetics of the SBH dehydrogenation was conducted under the elevated pressure condition. As a result, the dual roles of the catalysts as proton collectors and heat sources were revealed, both of which are essential for improving hydrogen production efficiency. We hope that our research stimulates subsequent research that pave the way to exploit hydrogen as an energy vector and achieve a more sustainable future society., (© 2024 Wiley-VCH GmbH.)

Gas bubble is a common defect in high-purity fused silica materials, but the formation of the second phase particles related to gas bubble and its mechanism remain unclear till now. In this work, we have presented a method for characterization of colored gas bubbles in high-purity fused silica crucibles for Czochralski silicon by the means of TEM and EDX. Based on it, the origin of the coloring of the gas bubbles is demonstrated to be induced by the gathering of Fe impurity and then, the formation of high-density second phase—ferric oxide (Fe 2 O 3) crystals around the gas bubbles. Moreover, our results provide insight into the formation mechanism of second phase crystals which can be induced by stress field variations around gas bubbles during the cooling process that probably promoted by volume shrinkage effect and increasing solubility of gas from gas bubbles into fused silica substrate. The understanding of the second phase particle formation mechanism in high-purity fused silica materials is valuable for its further controlling. [ABSTRACT FROM AUTHOR]

Electron beam melting(EBM) is a useful technique to obtain high-purity metal ingots. It is also used for melting refractory metals such as tantalum, which require melting techniques employing a high-energy heat source. Drawing is a method which is used to convert the ingot into a wire shape. The required thickness of the wire is achieved by drawing the ingot from a drawing die with a hole of similar size. This process is used to achieve high purity tantalum springs, which are an essential component of lithography lamp in semiconductor manufacturing process. Moreover, high-purity tantalum is used in other applications such as sputtering targets for semiconductors. Studies related to recycling of tantalum from these components have not been carried out until now. The recycling of tantalum is vital for environmental and economic reasons. In order to obtain high-purity tantalum ingot, in this study impurities contained in the scrap were removed by electron beam melting after pre-treatment using aqua regia. The purity of the ingot was then analyzed to be more than 4N5 (99.995%). Subsequently, drawing was performed using the rod melted by electron beam melting. Owing to continuous drawing, the diameter of the tantalum wire decreased to 0.5 mm from 9 mm. The hardness and oxygen concentration of the tantalum ingot were 149 Hv and less than 300 ppm, respectively, whereas the hardness of the tantalum wire was 232.12 Hv. In conclusion, 4N5 grade tantalum wire was successfully fabricated from tantalum scrap by EBM and drawing techniques. Furthermore, procedure to successfully recycle Tantalum from scraps was established.

Plant-based biogenic silicon dioxide nanoparticles are used to produce catalysts, additives, templates for deposition of other semiconductors and metals, nanomaterials with novel properties, bio-nanocomposites for biomedical, energy and environmental fields. There are too many ways of bio-SiO2 production. Dependent on the way and obtaining condition some properties of the plant-based biogenic silicon dioxide nanoparticles can be changed. The most amount of silicon is accumulated in stalks and husk biomass of rice, buckwheat and oats. The aim of our work was the investigation of physic-chemical properties of the biogenic silicon dioxide obtained from the rice husk by both ecologically- and economically-friendly technology. The fluoric technology was used for silicon dioxide isolation. Our technology allows us to restore used catalysts. Thus this technology is ecologically and economically efficient. The synthesised SiO2 was studied by using the following methods: low-temperature nitrogen sorption–desorption, XRD, XRF, ICP-MS, AFM, FTIR-ATR, SEM-EDS, TGA. It was established that obtained samples had a specific surface area 107 m2/g. The XRD of the powdered SiO2 showed 100% amorphous characteristics of the material. FTIR, XRF SEM-EDS, ICP-MS and X-ray diffraction indicated that samples contain only SiO2. AFM results show obtained silica particles were having shape from spherical to lamellar. According to SEM investigated sample consists of spherical small aggregates. [ABSTRACT FROM AUTHOR]

High-purity rayon-based carbon fiber (CF Ray) felt holds significant promise for applications in thermal protection systems and semiconductor crystal growth furnaces. This study employs halogen gas purification and high-temperature purification techniques in the fabrication of high-purity CF Ray felt. Additionally, the influence of the purification process on the thermal insulation and oxidation resistance of CF Ray felt is investigated. The glow discharge mass spectrometer analysis reveals that purification at a lower temperature of 2300 °C achieves a purity level of 6.9 ppm, surpassing both purified CF Ray felt without halogen at 2300 °C (56.1 ppm) and high-temperature treated CF Ray felt at 3000 °C (10.4 ppm). Thermal insulation and dynamic-static oxidation resistance tests show that the properties of CF Ray felt are concurrently affected by the heat treatment temperature. Compared to high-temperature purification, halogen gas purification operates at lower temperatures, preventing the graphitization of CF Ray , thereby ensuring high purity while enhancing thermal insulation and demonstrating relatively superior oxidation resistance. This study offers novel insights into the preparation and performance adjustment of high-purity CF Ray felt. [Display omitted] [ABSTRACT FROM AUTHOR]

Hexagonal boron nitride (h-BN) is widely used in the fields of pollutant adsorption and aerospace due to its low density, good electrical insulation, and excellent thermal conductivity. The precursor was prepared by using a liquid-phase method and then calcined in a flowing nitrogen atmosphere to achieve highly efficient preparation of high-purity h-BN and obtain h-BN short fibers. The chemical composition and generation rate of the precursor prepared at different BA(H 3 BO 3):M(C 3 N 6 H 6) ratios were characterized. The possible chemical synthesis reactions for converting raw materials into h-BN were discussed. The morphology and composition of h-BN short fibers were investigated, and the selective adsorption and reusability of h-BN short fibers was also analyzed. Results indicated that when the ratio of BA:M was 3:1, the generation rate of the precursor was the largest, reaching 85.424%. The maximum conversion rate of h-BN prepared from the precursor calcined in a flowing nitrogen atmosphere was 19.51%. When the BA:M ratio was 1:1 or 3:1, the obtained h-BN short fibers contained the least impurities, and the atomic content of O element was only 5.85%. The maximum specific surface area of h-BN fibers was 1144 m2/g and the main pore sizes were 1.72 nm and 3.78 nm. The maximum adsorption rate and adsorption capacity of h-BN short fibers to methylene blue (MB) reached 95.413% and 494.5 mg/g, respectively. The h-BN short fibers can rapidly adsorb MB from a mixed solution of MB and Cu2+, indicating that they have high adsorption selectivity for MB. After 5 times adsorption, the adsorption rate of the h-BN fibers to MB was still larger than 90%. This finding showed that the high-purity h-BN short fibers prepared in a flowing nitrogen atmosphere had the potential to selectively adsorb contaminants in the field of water treatment. [ABSTRACT FROM AUTHOR]

High-purity SiC materials have been used in semiconductor processes due to their excellent properties. However, they are difficult to densify without sintering aids. In this work, dense and high-purity SiC ceramics have been obtained by pressureless solid-state-sintering with ultra-low contents of sintering additives. The amount of residual B, C and O in the high-purity SiC ceramics was less than 0.15 wt%, respectively, and the total content of other impurity elements (such as aluminum, magnesium, calcium, iron, etc.) was less than 0.015 wt%. Finally, the purity of the as-prepared SiC ceramics was more than 99.5 wt%. [ABSTRACT FROM AUTHOR]

This paper contains data of the research project FVA 293 III by Schurer et al. and investigates the tooth root bending strength and the fatigue fracture characteristics of case-carburized and shot-peened gears of different sizes. The investigated carburized and shot-peened gears are made out of high-purity steel batches of the materials 20MnCr5 and 18CrNiMo7-6. Three different gear sizes with the normal modules mn = 1.5, 5, and 10 mm are examined in pulsator test rigs. Additionally, gear running tests in the FZG back-to-back gear test rigs for the gear size mn = 1.5 are performed. [ABSTRACT FROM AUTHOR]

Temperature detection based on the fluorescence intensity ratio (FIR) has been considered to be a promising technique for non-contact temperature measurement. Unfortunately, the FIR-based temperature sensor materials generally show low temperature sensitivity because of the narrow energy gap between the thermally coupled energy levels. In this work, lanthanide-doped Ba 3 Y 4 O 9 (BYO) upconversion luminescent materials were synthesized in order to explore their potential application in optical thermometer. The crystal structure of the present samples was investigated by XRD and further refined by the Rietveld method, which indicate that the dopant ions successfully enter the host lattice by occupying Y3+ sites. Excited by 980 nm, BYO:Ho3+/Yb3+ and BYO:Tm3+/Yb3+ present high-purity green and blue output colors, respectively. Based on the analysis of emission intensity ratio and pump-power dependence, the upconversion emission mechanisms are systematically investigated. Subsequently, the temperature sensing performances of BYO:Ho3+/Yb3+ and BYO:Tm3+/Yb3+ based on FIR technique are evaluated in the temperature range of 298–573 K under 980 nm excitation. Owing to the different temperature-dependent behaviors of different emission bands and larger energy gaps, the present materials display high sensitivity, good repeatability and excellent stability. The maximum absolute sensitivity of BYO:Ho3+/Yb3+ and BYO:Tm3+/Yb3+ reach as high as 79.62 × 10−4 K−1 and 193.51 × 10−4 K−1, respectively. Among them, the highest sensitivity of BYO:Tm3+/Yb3+ is far higher than those of other optical temperature sensors using the thermally coupled levels based on FIR technique. The results indicate that the present materials are promising for application as optical thermometer in non-contact temperature detection, and using FIR of 5F 1 /5G 6 and 5F 2,3 /3K 8 multiplets (Ho3+), and 3F 2,3 /1G 4 (Tm3+) are feasible methods for accurate temperature detection. [ABSTRACT FROM AUTHOR]

Equilibrium and nonequilibrium phase diagrams of the AlCl 3 -NaCl-H 2 O(-HCl-C 2 H 5 OH) salt water system were drawn and these were used to optimize the separation technology for solving the problem of aluminum chloride hexahydrate extracted from hydrochloric acid leach liquor with low purity because of the contamination of sodium chloride. The phase diagram of the AlCl 3 -NaCl-H 2 O(-HCl-C 2 H 5 OH) system is a simple eutonic type. It is weakly dependent on temperature but is greatly affected by hydrochloric acid and ethanol. Acidity can nonselectively decrease the solubility of the two salts, and this leads to similar aluminum/sodium ratios in the co-saturated liquid phase with different acidities and temperatures. As a result, the obtained aluminum chloride hexahydrate has a maximum purity of 96.65%. Adding ethanol to the system can increase the differences in solubility and crystal size between the two salts. Thus, in accordance with the theoretical route of evaporation and ethanol-assisted re-dissolution, aluminum chloride hexahydrate crystals were precipitated with a higher purity of 99.50%. Unlabelled Image • The solid-liquid equilibrium data of AlCl 3 -NaCl-H 2 O(-HCl-C 2 H 5 OH) system was obtained. • The problem of separation between dissolved AlCl 3 and NaCl was preliminarily solved. • AlCl 3 ·6H 2 O with 99.50% purity was directly separated from the acidic solution. [ABSTRACT FROM AUTHOR]

Abstract The high-purity α-Si 3 N 4 nano-powder without any β-Si 3 N 4 impurities was prepared by using a precursor-carbothermal reduction and nitridation method, and the detailed technical parameters were optimized. Using HNO 3 and CO(NH 2) 2 as reaction raw materials, C 6 H 12 O 6 ·H 2 O as carbon source and SiO 2 as silicon source, a porous precursor was prepared at 350 °C, in which the SiO 2 particles were uniformly distributed and in full contact with C. This precursor can be transformed into high-purity α-Si 3 N 4 nano-powder under such optimal technical conditions as the nitriding temperature of 1500 °C, the nitriding duration of 1 h and the nitrogen flow rate of 1800 ml/min. As intermediate products, SiO and Si 2 N 2 O were considered to be involved in the carbothermal process, and the presence of SiO accelerated the carbothermal reaction. Furthermore, the higher nitrogen flow rate took more heat away from the reaction area, suppressing the transformation from α-Si 3 N 4 to β-Si 3 N 4 , which might explain why the final products are mainly composed of high-purity α-Si 3 N 4 powder. [ABSTRACT FROM AUTHOR]

The existence of many background cells and the size overlap between white blood cells (WBCs) and malignant tumor cells (MTCs) pose a challenge for the efficient separation of MTCs from effusions or bloods. Herein, we proposed an inertia-magnetic cell separation (IMCS) device integrating a trapezoidal spiral chip with an immunomagnetic chip for high-throughput, high-recovery, and high-purity separation of MTCs from malignant pleural and peritoneal effusions (MPPEs). First, the effects of flow rate and particle size on separation performances in two separate chips were investigated. Then, the performances of the integrated IMCS device were characterized using blood samples spiked with three different tumor cells (A549, MCF-7, and MDA-MB-231 cells). The results showed that all the three tumor cells were separated from the WBCs with a high-throughput of ∼ 3200 μL/min, a high-recovery ratio of > 90%, and a high-purity of > 70%. Finally, we successfully separated MTCs from four clinical MPPE samples with an average purity of > 70%. As compared with conventional microfluidic devices using single technologies, our IMCS device combines the advantages of both passive size-dependent separation technology and immunomagnetic separation technology and can accurately separate tumor cells from WBCs of comparable sizes at a high throughput. Therefore, we envision that the high-purity MTC separation ability of our IMCS device can improve the sensitivity and efficiency of cytological examination. [Display omitted] • Passive size-dependent separation technology and immunomagnetic separation technology were combined. • Tumor cells were accurately separated from WBCs of comparable sizes. • Integrated device was used for the separation of multiple tumor cells from WBCs. • Malignant tumor cells were separated with an average purity of > 70%. [ABSTRACT FROM AUTHOR]

High-purity trilinolein and triolein were prepared by Novozym 435-catalyzed esterification reaction combined with column chromatography purification in this study. Firstly, linoleic acid and oleic acid were respectively extracted from safflower seed oil and camellia seed oil by urea adduct method. Secondly, trilinolein and triolein were synthesized through Novozym 435 catalyzed esterification of glycerol and fatty acids. The best synthesis conditions were obtained as follows: reaction temperature 100℃, residual pressure 0.9 kPa, enzyme dosage 6%, molar ratio of glycerol to linoleic acid 1:3 and reaction time 8 h. Crude trilinolein and triolein were further purified by silica gel column chromatography. Finally, highpurity trilinolein (95.43±0.97%) and triolein (93.07±1.05%) were obtained. [ABSTRACT FROM AUTHOR]

Accurate prediction of Mg corrosion rates within the body ( in vivo ) based on laboratory tests ( in vitro ) is a key challenge for Mg alloys in medical applications. Estimates based on in vitro measurements overestimate the measured Mg corrosion rate in vivo . This indicates that the medical environment and the biocorrosion mechanism is not fully characterised. We summarise (i) the relevant Mg metallurgy, and (ii) the solution factors that influence Mg corrosion in vitro . We analyse the reasons for the disparity between the corrosion rates in vivo and the expected corrosion rates based on in vitro testing, and suggest promising areas of research. [ABSTRACT FROM AUTHOR]

2D black arsenic phosphorus (b-AsP) is a promising candidate for infrared photodetectors. However, directly synthesizing high-purity b-AsP crystals under the existing system is an intractable task. Herein, we report a novel system for synthesizing high-purity b-AsP crystals using non-metallic mineralizer. A small amount of I 2 was chosen as the sole additive for the synthesis of b-AsP to avoid metal by-products, and impurities were removed through the reverse heating program after the reaction. Through optimization of process conditions, the efficient conversion rate of b-AsP was> 99%, and the purity of b-AsP crystal was as high as> 99.9% with favorable crystal form, diameter of ∼5 mm, and typical polycrystalline characteristics. The entire synthesis process took only 15 h. This facile and green route for b-AsP crystals synthesis might be expected to replace the existing b-AsP synthesis system and provide theoretical guidance for breakthroughs in the synthesis reaction mechanism of b-AsP materials. [Display omitted] • The black arsenic phosphorus was synthesized for the first time with non-metallic mineralizer. • A small amount I 2 was chosen as the sole additive to avoid metal by-products. • The conversion rate of black arsenic phosphorus was> 99%. • The purity of black arsenic phosphorus crystal was as high as> 99.9%. [ABSTRACT FROM AUTHOR]

This essay studies a novel environment-friendly synthesis method for the high purity micron iron phosphate. Compared with traditional synthesis method, this new method can greatly reduce the amount of industrial sewage, hence it is an environment-friendly production technology which can effectively improve the products’ purity, structure stability and morphological consistency. This new method includes two-step reactions: first, phosphoric acid, iron powder and hydrogen peroxide are used as raw materials to obtain iron phosphate dihydrate intermediate, which is then calcined at high temperature to obtain anhydrous iron phosphate. The results show that the iron phosphate prepared for this new method is a hexagonal system-structured iron orthophosphate with high purity and without any impurities, exhibiting a regular and primary spherical particle morphology, at the average size of 3.096 μ m in particle and the specific surface area reaching 39.1765 m ^2 g ^−1 . With these excellent characteristics, it has better application potentials in the field of electrode material preparation. The electrochemical performance of lithium iron phosphate anode materials synthesized with it as the precursor is superior to those synthesized with the iron phosphate prepared by the traditional method as precursor. The first specific capacity of discharge at 0.5C and 10C can be as high as 154.3989 or 102.9326 mAh g ^−1 , increasing by 2.74% and 8.03%, respectively.

In this paper, the development of an accelerating structure with high-purity copper operated at approximately 20 K is described. The aim is to obtain a dramatic increase in the quality factor ( Q factor), which is an important parameter as regards enhancement of the acceleration gradient in a normal-conducting accelerating structure that has been operated at room temperature in the past. First, the Q factors of pillbox cavities comprised of two types of copper with different purities (99.99% and 99.99998%) were measured, at room temperature (300 K) and at a relatively low temperature (20 K); the resultant ratios, Q 0 (20 K)/ Q 0 (300 K), were then compared with calculated values. Hence, it was found that the experimental and calculated values agree to within several percent, and converge to a constant value (approximately 5.3) when the residual resistance ratio is above 500. Next, a C-band accelerating structure was fabricated using a copper material having a purity of 99.99998%, and high-power testing of the structure was conducted at 20 K. Hence, it was found that the accelerating gradient E acc reaches 30.9 MV/m with a 1.0- μ s pulse width and 50-Hz repetition rate. In the high-power test, it was revealed that the radiation dose rate for C-band structure (20 K) was about two orders of magnitude lower than that for S-band structure (303 K) under the same conditions. Further, the magnitude of the dark current generated in this structure was estimated to be several femtoamps, which was below the detection limit. This finding was based on the assumption that the dark current magnitude is proportional to the radiation dose; however, no dark current was observed. [ABSTRACT FROM AUTHOR]

CM 2 A 8 is a solid solution of MA and CA 6 . As a component in the ternary phase diagram of CaO-Al 2 O 3 -MgO, it was not reported in detail. So in this work, analytically pure CaO, MgO and Al 2 O 3 were adopted as starting materials and batched stoimotrically according to CM 2 A 8 . The raw materials were ground, mixed, shaped and reaction-sintered at different temperatures (1550 °C, 1650 °C, 1700 °C, and 1750 °C) to synthesize CM 2 A 8 . The synthesized specimens were analyzed by XRD, SEM, and TEM and the corrosion mechanism against LF slag was also researched. The results show that high-purity CM 2 A 8 can be synthesized by reaction sintering at 1750 °C. During synthesis, granular MA and flake CA 6 form and grow together; at 1650 °C, they solid-solve together to form C 2 M 2 A 14 . As the temperature rises, solid solution reaction goes on, which results in the disappearance of CA 6 , C 2 M 2 A 14 , and MA in succession and forms high-purity CM 2 A 8 growing towards hexagonal column crystals. In the high temperature reaction between CM 2 A 8 and steel slag, Ca 2+ in the slag reacts with CM 2 A 8 to form CA 2 , damaging the structure of CM 2 A 8 and releasing excessive Mg 2+ and Al 3+ which move towards the molten slag. As the reaction between Ca 2+ and CM 2 A 8 proceeds, a dense CA 2 coating forms on the surface of CM 2 A 8 . The slag viscosity increases as well because of the entrance of Mg 2+ and Al 3+ . Thus, the formation of the CA 2 coating and the enhancement of the slag viscosity restrain the penetration and corrosion of slag towards CM 2 A 8 . [ABSTRACT FROM AUTHOR]

high purity fluorapatite (FA) with rod-like and spherical-like morphology was synthesized via sol-gel method. Chemical characterization of FA powders was done by XRD and FTIR analyses. Crystallite samples were calculated using Scherer method. Morphology of FA powders was investigated with TEM and SEM images. The results revealed that increasing the time of hydrolysis of phosphate sols significantly decreased the gelation time of FA sols. Also, mixing temperature of P and Ca sols affects the gelation time of samples and increasing pH decreases the gelation time of FA sols. Morphological and chemical characterization of samples showed that the FA powders have high purity and rod-like and spherical-like morphology.

A high-purity As 40 S 59 Se 1 /As 2 S 3 core/cladding step-index fiber for supercontinuum generation was fabricated in this study. The glass rods were obtained by using a relatively effective and inexpensive method of modified physical and chemical purification. Then, the multi-material fiber preform was fabricated through a modified laboratory using one-step co-extrusion process. Moreover, the fiber preform with a Polyether Sulfone (PES) polymer was drawn with a core diameter of ~ 22 μm. The core/cladding ratio of the fiber was approximately 1:17, and the minimum loss was approximately 1 dB/m between 4 and 6 μm. By pumping a 13 cm-long fiber with different laser powers and another two different lengths (20 cm and 50 cm, respectively) of fiber at 4.8 μm, a supercontinuum covering 1–5 μm could be recorded in all fibers. This study attained a 1–5 μm supercontinuum that covered the second atmospheric window. Result of this study can be a promising reference in the production of mid-infrared light source. [ABSTRACT FROM AUTHOR]

Improvements in technologies to yield purer circulating tumor cells (CTCs) will enable a broader range of clinical applications. We have previously demonstrated the use of a commercially available cell-adhesion matrix (CAM) assay to capture invasive CTCs (iCTCs). To improve the purity of the isolated iCTCs, here we used fluorescence-activated cell sorting (FACS) in combination with the CAM assay (CAM + FACS). Our results showed an increase of median purity from the CAM assay to CAM + FACS for the spiked-in cell lines and patient samples analyzed from three different metastatic cancer types: castration resistant prostate cancer (mCRPC), non-small cell lung cancer (mNSCLC) and pancreatic ductal adenocarcinoma cancer (mPDAC). Copy number profiles for spiked-in mCRPC cell line and mCRPC patient iCTCs were similar to expected mCRPC profiles and a matched biopsy. A somatic epidermal growth factor receptor (EGFR) mutation specific to mNSCLC was observed in the iCTCs recovered from EGFR(+) mNSCLC cell lines and patient samples. Next-generation sequencing (NGS) of spiked-in pancreatic cancer cell line and mPDAC patient iCTCs showed mPDAC common mutations. CAM + FACS iCTC enrichment enables multiple downstream genomic characterizations across different tumor types. [ABSTRACT FROM AUTHOR]

This study indicates that the kinetic rate constants of oxidation weight gain and thickening both increase with the increasing content of O, N and S impurities. The oxide layer of the low-purity alloy is not tight and easy to peel off. Internal oxidation becomes more serious with the increase of oxygen solubility. The microscopic mechanism of how impurity atoms affect the oxidation diffusion process was explained, and the models of the oxide layer growth process for high-purity alloys and low-purity alloys were constructed, which provide a reference for the improvement of high-temperature oxidation performance of superalloys in the future. • With the increase of O, N and S contents, the kinetic rate constants of both oxidation weight gain and thickening increase. • The oxide layer on the surface of high-purity alloy is more uniform. • The depth of internal oxidation is proportional to the square root of the oxygen content in the matrix. • The area of the intermediate layer and the insufficient oxidation region increase with the increase of impurity content. • The effect of impurity content on oxidation thermodynamics and kinetics was studied. [ABSTRACT FROM AUTHOR]

Ruthenium is widely used as magnetic recording and electrode materials. In this study, high-purity micro-spherical Ru particles were synthesized from crude ruthenium sequential by distilling, precipitation, dry spraying and ignition. Impurities in the starting Ru powders were eliminated by distilled and precipitated treatments. The morphology and size of as-synthesized Ru particles were controlled by dry spraying and ignition processes. The influences of heating rate in ignited treatment on the morphology and size of Ru particles were investigated. The purity of as-synthesized Ru particles was higher than 99.995 wt%, and the average size was about 12 μm. It should be noted that the powder technology in this study could be applied to synthesize other metals particles with high-purity requirement. [ABSTRACT FROM AUTHOR]

The electric field effects on the shape of transmission spectra associated with exciton including continuum band transition in ultra-high-purity GaAs have been theoretically studied at room temperature. We have calculated the Stark red shift, linewidth broadening of exciton, height of exciton peak and extinction ratio with applied electric field. The theoretical results are compared with experimental and found the close agreement between them. [ABSTRACT FROM AUTHOR]

A chemical method was developed for low-temperature synthesis of DAG from MAG followed by an easy purification procedure in order to obtain high-purity DAG. Solvent-assisted and solvent-free reaction conditions were used, combined with different catalysts (sodium methoxide, p-toluenesulfonic acid, methanesulfonic acid, and sulfuric acid). All reactions were performed at 35 and 70 °C. By increasing both acidity and polarity of the catalyst the equilibrium shifts towards the formation of DAG. When using sulfuric acid in solvent-assisted condition at 70 °C, 88 % conversion was obtained after 20 min of reaction (77 % w/w DAG in the reaction mixture after evaporation of the solvent). After purifying by means of column chromatography, 96 % pure DAG were obtained. The overall yield of DAG was 81 %. [ABSTRACT FROM AUTHOR]

A novel and simple process for the preparative extraction, separation, and purification of high-purity (–)-borneol and xanthoxylin, synchronously, from the leaves ofBlumea balsamifera(L.) DC was developed. Simultaneous distillation and extraction, silica gel column chromatography, and recrystallization were applied to the preparation. Two objective compounds with the purity of 98% were obtained, and the losses were minimal during the whole procedure. It is the first time that the preparation of high-purity (–)-borneol and xanthoxylin at the same time were achieved. [ABSTRACT FROM AUTHOR]