Contents Of Re Research Articles

Variation in ginsenoside content and composition within the American ginseng population.

The contents of 57 ginsenosides were measured in American ginseng roots collected from a single population grown in Jilin. Ginsenoside contents and compositions varied significantly among the population. The most abundant ginsenoside within the American ginseng root and by population was either Rg1 or Re, followed by Rb1, mal-Rb1, Rd, Rc, pseudoginsenoside F11, Ro, and gypenoside XVII. According to the relative contents of Rg1 and Re, the population was grouped into two chemotypes, and there were significant differences in ginsenoside profiles between them. The contents of protopanaxadiol-type ginsenosides were relatively stable. The rate-limiting enzymes of malonyl ginsenosides biosynthesis were located in front of their corresponding neutral ginsenosides. The regulatory sites of the oleanolic acid-type ginsenosides biosynthetic pathway were in front of the β-amyrin.

Research on tribological properties of new Ni-based single crystal alloy containing Re

Abstract The particles in high-temperature and high-speed airflow in the battlefield environment will form sliding friction and wear on the aeroengine turbine blades, thus reducing the service performance of the blades. However, few studies has been reported on the tribological properties of Ni-based single crystal alloy. Accordingly, the tribological properties of Ni-based single crystal alloys with different contents of Re (0 wt%, 1.5 wt%, 2.5 wt%, 3.5 wt%, 4.5 wt% and 5.5 wt%) are investigated by tribological experiments and molecular dynamics simulations in this paper. The results of tribological experiments show that Ni-based single crystal alloy without Re exhibits the characteristics of abrasive wear and adhesive wear, while the wear state is significantly improved after adding Re element. In particular, the worn surface of Ni-based single crystal alloy containing 5.5% Re (NSCA5) is the smoothest and only a few minor defects are observed. In addition, the micro-tribological characteristics of Ni-based single crystal alloy are analyzed by molecular dynamics simulations, the results show that Re atoms can inhibit the dislocation movement and reduce the system potential energy, which enhance the stability and hardness of Ni-based single crystal alloy, thereby the wear resistance of the material are improved.

Integrated Analysis of Ginsenoside Content and Biomarker Changes in Processed Ginseng: Implications for Anti-Cancer Mechanisms.

Black ginseng is the processed product of ginseng, and it has been found that the content and types of rare ginsenosides increased after processing. However, there is limited research on the ginsenoside differences between cultivated and forest ginseng before and after processing and among various plant parts. This study investigated the effects of processing on ginsenosides in different parts of cultivated and forest ginseng. After processing, the contents of Re, Rg1, S-Rg3, Rg5, R-Rh1, Rk1, Rk3, and F4 were significantly increased or decreased, the growth age of forest ginseng was not proportional to the content of ginsenosides, and the differences in ginsenoside content in ginseng from different cultivation methods were relatively small. Chemometric analysis identified processing biomarkers showing varying percentage changes in different parts. Network pharmacology predicted the EGFR/PI3K/Akt/mTOR pathway as a potential key pathway for the anti-cancer effect of black ginseng.

Fermented Ginsenosides Alleviate Acute Liver Injury Induced by CCl4 in Mice by Regulating the AKT/mTOR Signaling Pathway.

This study investigated the alleviating effect of fermented ginsenosides obtained through yeast strain fermentation transformation on acute liver injury (ALI) induced by CCl4. Strains were screened for their ability to produce β-glucosidase, the transformation ability of the strain was verified by high-performance liquid chromatography, and the Saccharomyces cerevisiae strain F6 was obtained by 26S rRNA sequencing. After fermentation by F6 strain, it was found that the content of ginsenosides Re, Rb1, and Rb2 was significantly decreased (P < 0.05), and rare ginsenosides were detected, with the content of Rh4 and Rg5 reaching 2.65 mg·g-1 and 2.56 mg·g-1. We also explored the preventive effect of fermented ginsenoside extract (FGE) on ALI. Mice were evenly divided into 9 groups as follows: control group, ALI model group, positive drug bifendate group, and treatment group, which included 3 ginsenoside extract (GE) groups and 3 FGE groups (dosage of 150, 300, and 450 mg·kg-1 b.w.). The results showed that compared with the ALI model group, FGE significantly increased the levels of glutathione peroxidase, hydroperoxidase, and superoxide dismutase and also decreased the malondialdehyde level. The levels of alanine aminotransferase, aspartate aminotransferase, and total bilirubin markers were significantly reduced, and the levels of inflammatory cytokines TNF-α, IL-6, and IL-1β were significantly decreased. Bioinformatics analysis combined with Western blot validation explored the molecular mechanism of the effect of FGE. It was found that FGE could downregulate the expression of the p-AKT/AKT and the p-mTOR/mTOR ratios. These results suggested that FGE played an alleviative role in ALI by promoting autophagy to inhibit the AKT/mTOR signaling pathway.

Research on the Effect Mechanism of Re on Interface Dislocation Networks of Ni-Based Single Crystal Alloys.

The effect of interface dislocation networks on the mechanical properties of new Ni-based single crystal alloys containing Rhenium (Re) is very large. Because the interface dislocations are microscopic in the nano-scale range, this has not been investigated, and it is very difficult to prepare new Ni-based single crystal alloys containing Re. Therefore, six kinds of new Ni-based single crystal alloys containing Re were prepared, and the hardness tests and nonlinear ultrasonic lamb wave tests were performed on the samples. It was found that the density of interface dislocation networks increases with the increase in the content of Re, which improves the blocking ability of matrix phase dislocation cutting into precipitated phase and enhances the inhibition of dislocation movement. The nonlinear ultrasonic lamb wave tests showed that the materials exhibit better mechanical properties when the density of the interface dislocation networks increases. Meanwhile, a new molecular dynamics model which is closer to the real state of an Ni-based single crystal alloy was constructed to reveal the evolution mechanism of interface dislocation networks. The results showed that the potential energy of Re atoms at the interface is the lowest, which affects the reduction of the potential energy of other atoms at the interface, and thus the stability of the model is improved. In addition, according to the change in the total length of dislocation loops in the model system, with the increase in the content of Re atoms, the inhibition of dislocation movement by dislocation networks at the interface is strengthened.

HPLC-MS Analysis of Ginsenosides in Morphogenic Cell Cultures of Ginseng (Panax ginseng C.A. Meyer)

The composition of triterpene glycosides in different in vitro tissues of cell lines (PgR–rhizogenic and PgG–hemogenic) and roots of ginseng plants (Panax ginseng C.A. Meyer), grown on plantations in Primorsky Krai (Russian Federation) was determined using the HPLC-MS method. More than 60 triterpene glycosides have been detected and characterized. The maximum content of ginsenosides was identified in the leaves of the hemogenic line. The total amount of ginsenosides in the PgG line embryonic tissue was lower compared to all other samples studied mainly due to the amount of protopanaxadiols. In all parts of the PgR line, the content of protopanaxatriol Re was two times higher than in the root of the intact plant. A high content of protopanaxatriols and oleanolic ginsenosides was found in the basal parts of PgR and PgG calli. Thus, morphogenic cell lines not only repeated the pattern of qualitative ginsenosides composition in comparison with individual parts of native roots and leaves but also demonstrated an increase in their diversity and quantity.

Composition and temperature dependence of kinetic behavior of γ′ precipitation in Ni–Al–Cr–Mo quaternary model superalloys: A phase field study

The characteristic of the γ′ strengthening phase plays a crucial role in the development of high performance nickel-based superalloys, which is strongly dependent on the kinetic behavior of γ′ precipitation. Herein, the precipitation kinetics of the nanoscale γ′ phase in Ni–10 Al–8.5 Cr–x Mo at% (x = 2, 3, and 4) quaternary alloys aged at 1073 K are investigated using CALPHAD-assisted phase field simulations. Our calculations show that the higher Mo content and lower aging temperatures delay the growth and coarsening kinetics of the γ′ phase, which can be attributed to the decrease of Al chemical mobility. Moreover, although Mo is a γ–stabilized element, previous experiments, thermodynamic calculations, and our simulations all indicate that the γ′ volume fraction increases abnormally with increasing Mo concentration in Ni–Al–Cr–Mo quaternary alloys, which is attributed to Mo occupying the Al sites of γ′-Ni3Al and the elemental partitioning behaviors between the γ matrix and the γ′ phase. In addition, Mo is a potential element to reduce the content of Re and W elements in nickel-based superalloys because of its lower density and stronger solid solution strengthening effect in the γ matrix. Our work can guide the design and development of lightweight nickel-based superalloys with superior microstructural stability and mechanical properties for engineering applications.

Occurrence state and enrichment mechanism of rhenium in molybdenite from Merlin Deposit, Australia

Rhenium (Re) is one of the critical metals, and molybdenite (MoS2) is the main host mineral for Re. Previous studies have shown that the distribution of Re in molybdenite is highly heterogeneous, and the occurrence state and enrichment mechanism of Re in molybdenite is not clear. The molybdenite of Merlin deposit has typical Re rich characteristics, which is an ideal object to study the occurrence state and enrichment mechanism of Re in molybdenite. Based on the geological research of the deposit, this study systematically investigated the Re-rich molybdenite of the Merlin deposit using LA-ICP-MS and STEM techniques. The LA-ICP-MS results showed that the content of Re in molybdenite ranged from 67 to 2726 ppm, and the distribution of Re content in molybdenite was extremely uneven and irregular. The STEM results showed that there was no independent Re mineral in molybdenite, and Re atoms were found to substitute molybdenum (Mo) atoms in situ in the Re-rich area of molybdenite. The substitution mechanism of Re was clarified at the atomic scale in a visual form, and a corresponding rigid sphere stacking model was established. Mo atoms are sandwiched between two layers of S atoms, while Re atoms enter the molybdenite lattice and substitute Mo atoms in situ, thus changing the lattice structure of the original molybdenite matrix. Rare lattice defects such as five-fold twinning were identified in the Re-rich area of molybdenite in high-resolution HAADF STEM images, which are related to plastic deformation caused by the low stacking fault energy and stress of hexagonal molybdenite. It is speculated that lattice defects such as five-fold twinning is an important mechanism for the enrichment of Re in molybdenite. The magmatic-hydrothermal fluids released from the intrusion of igneous rocks may have provided the main source of ore-forming materials for the Merlin deposit. The ore-forming fluids, which are rich in Mo4+ and Re4+, underwent redox reactions with carbonaceous shale, resulting in the decrease in temperature and oxygen fugacity, and the increase in S2- concentration. This ultimately led to the precipitation and enrichment of Re4+ and Mo4+ to form the Re-rich molybdenite in the Merlin deposit.

Genetic diversity of Panax ginseng cultivated in Japan and its relation with some plant characteristics.

In East Asia, Panax ginseng is one of the most important medicinal plants and has been used in traditional medicines from ancient times. Today, P. ginseng is cultivated in Korea, China, and Japan. Although the genetic diversity of P. ginseng in Korea and China has been reported previously, that of P. ginseng cultivated in Japan is largely unknown. In the present study, genetic diversity of P. ginseng cultivated in Japan was analyzed using eight simple sequence repeat markers that have been used in other studies, and the results were compared with previous results for Korea and China. The correlation between genetic diversity and plant characteristics, such as ginsenoside contents, were also examined. The genetic diversity of P. ginseng in Japan was substantially different from that in Korea and China, probably due to Japan's history of cultivation and the ginseng reproduction system of agamospermy. The genetic analysis indicated that P. ginseng cultivated in Japan could be classified into two clusters. The classification was related to the contents of ginsenosides Re and Ro in the main root but not to the cultivation region of the samples. These results may be useful for the cultivation and quality control of P. ginseng in Japan.

Super-enrichment of ultra-low concentration rhenium via synergistic co-flocculation precipitation using CTAB and ferric salt hydrolysis micelles

Super-enrichment and recovery of associated Rhenium (Re) in sandstone-type uranium deposits is challenging due to its sparse distribution and ultra-low contents in raw ores. Conventional industrial processes are extremely difficult to achieve economic recovery of Re with a concentration below 0.1 mg/L from in-situ leaching solutions of sandstone-type uranium deposits. This study proposes a novel approach for achieving super-enrichment ultra-low concentration of Re using a synergistic co-flocculation precipitation system composed of cetyltrimethylammonium-bromide (CTAB) and ferric salt (FeCl3) hydrolysis micelles. Experimental results reveal that the enriched content of Re in the co-flocculation precipitates is as high as 503 g/t, nearly 3353 times higher than that in the in-situ leaching solutions. The synergistic precipitation percentage of Re can reach more than 60%, which is larger than the sum of using CTAB micellar flocculation (30.16%) and FeCl3 hydrolysis micellar flocculation (5.43%) separately. Furthermore, the synergistic co-flocculation and precipitation mechanism of Re is examined by SEM, turbidity, Fourier transform infrared spectroscopy, Zeta potential analysis, and DTF calculations. Results demonstrate that the ReO4- anions first form ion associations with CTA+ cations through electrostatic force, which are subsequently captured to forms insoluble co-flocculating precipitate via weak intermolecular hydrogen bond force between Fe(OH)3 and ReO4-, which promotes the super-enrichment of the ultra-low concentration Re. In summary, this process presents great potential for the efficient recovery Re from a large amounts of sandstone-type uranium deposits leaching solution, and provides new insights into the enhancement mechanism of synergistic co-flocculation precipitation.

Resource components and utilization values of different parts of Panax quinquefolium in Shandong province

To explore the resource components and availability of different parts of Panax quinquefolium in Shandong province, the paper employed the non-targeted metabolomics technology based on ultra-high performance liquid chromatography-tandem mass spectrometry(UPLC-MS/MS) to analyze the metabolites and their metabolic pathways in the root, fibril, stem, and leaf of P. quinquefolium. The content of seven ginsenosides and polysaccharides in different parts was determined by high performance liquid chromatography(HPLC) and ultraviolet-visible spectrophotometry(UV-Vis). The results showed that the metabolites were mainly sugars, glycosides, organic acids, amino acids and their derivatives, terpenoids, etc. The total abundance of metabolites followed the trend of leaf &gt; root &gt; fibril &gt; stem. Most of the differential metabolites were concentrated in phenylpropane biosynthesis, flavonoid biosynthesis, citric acid cycle, and amino acid biosynthesis. The leaf contained high levels of sugars, glycosides, amino acids and their derivatives, and flavonoids; the root was rich in terpenoids, volatile oils, vitamins, and lignin; the fibril contained rich organic acids; and the stem had high content of nucleotides and their derivatives. The content of ginsenosides Re and Rb_1 was significantly higher in the root; the content of ginsenosides Rg_1, Rg_2, Rd, F_(11), and polysaccharide was significantly higher in the leaf; and the content of ginsenoside Rb_2 was significantly higher in the stem. We analyzed the resource components and availability of different parts of P. quinquefolium, aiming to provide basic information for the comprehensive development and utilization of P. quinquefolium resources in Shandong province.

Genesis of Makeng-type Fe-polymetallic deposits in SE China: New constraints by geochronological and isotopic data from the Dapai–Makeng metallogenic system

The southwestern Fujian depression belt (SFDB) is an economically important Mesozoic Fe metallogenic belt in South China and is renowned for its Makeng-type Fe deposits, in which stratified skarn Fe orebodies generally occur in or near the contact zone between late Paleozoic carbonate sequences and Mesozoic granites. However, the genesis and geodynamic setting of these deposits remain unclear because the characteristics of the widely distributed Pb–Zn–Cu and Mo orebodies in these deposits and the temporal, spatial, and genetic relationships between magmatism and mineralization are poorly defined. The Dapai Fe polymetallic deposit in the SFDB is a typical example of Makeng-type Fe deposits but also has regional significance, whereby the stratified skarn Fe orebodies have overprinted the stratabound Pb–Zn–Cu mineralization followed by final fissure-filling by vein-disseminated Mo mineralization. A detailed geological investigation suggests that episodic magmatic–hydrothermal events were involved in the formation process of the Dapai Fe polymetallic deposit.Pyrite and sphalerite from the Pb–Zn–Cu orebodies yield an Rb–Sr isochron age of 175.5 ± 3.3 Ma, which is regarded as the timing of Pb–Zn–Cu mineralization. Zircon grains from Fe-mineralized granodiorite porphyry and Mo-mineralized monzogranite yield weighted-mean 206Pb/238U ages of 146.3 ± 0.9 Ma and 131.7 ± 0.4 Ma, interpreted as the timings of Fe and Mo mineralization, respectively. Six zircons from granodiorite also yield a 206Pb/238U model age cluster of ∼184 Ma, which coincides reasonably with the timing of Pb–Zn–Cu mineralization and implies the existence of an unidentified ore-related intrusion in the Dapai deposit. Five further zircons from the porphyritic granodiorite yield an age cluster of ∼150 Ma, consistent with the timing of Fe mineralization. Galena, pyrite, and sphalerite from the Dapai and Makeng deposits have similar S–Pb isotopic compositions and suggest a magmatic source. Combining our results with published isotopic data for the SFDB, we suggest that the Pb–Zn–Cu mineralization in this area was derived from crustal magmas that mixed with mantle-derived magma prior to emplacement. The δ56Fe and δ57Fe values of magnetite from Dapai and Makeng are both slightly lower than those of the ore-related granites, suggesting that Fe in the initial fluid in both deposits was derived mainly from coeval granitic rocks. The Fe isotopic variation between intrusions and skarn Fe orebodies is interpreted as resulting from mass fractionation that occurred during fluid exsolution from melt. Contents of Re in molybdenite from published data for the SFDB indicate crust–mantle mixed sources of Mo and Re. The Makeng-type Fe polymetallic deposits formed as a result of three magmatic–hydrothermal episodes, generating Pb–Zn–Cu mineralization at 185–160 Ma, Fe–Mo mineralization at 150–140 Ma, and Mo–Fe mineralization at 135–130 Ma. The different metal associations formed during multiple stages of magmatism caused by ongoing subduction and rollback and/or retreat of the paleo-Pacific Plate.

Preparation of RE-containing magnesium alloys via molten-salt-mediated magnesiothermic reduction

Abstract RE-containing magnesium alloys were prepared via molten-salt-mediated magnesiothermic reduction by using RE2O3 (RE=Y, Nd and Gd) and Mg metal as raw materials. The thermomechanical analysis of the magnesiothermic reduction reactions in molten salt was investigated. Then the molten-salt-mediated magnesiothermic reduction process was studied from three different perspectives. After that, the RE-containing magnesium alloy was characterized by using chemical analysis, XRD analysis and SEM analysis. The magnesiothermic reduction was a liquid-liquid reaction with relatively weak driving force. During the melting process and the magnesiothermic reduction process, magnesium metal and the obtained alloy went up and down as a whole in molten salt, which improved the process safety without introducing chloride inclusions. Meanwhile, the hydrolysis of the RECl3-containing molten salt occurred at elevated temperature, which severely impeded the magnesiothermic reduction process. After the magnesiothermic reduction at 750 °C for 2.0 h, the content of RE and the common impurity elements in the obtained RE-containing alloy met the both requirements of the commercial WE43A and WE43B.

Preliminary data on critical element contents in lignite from the Maritsa East basin, Bulgaria

The studied samples include three composite coal, three lithotypes (lyptain, xylain, and fusain), and a black clay parting from the Troyanovo 1 and Troyanovo North mines in the largest Maritsa East lignite basin in Bulgaria. Mineral matter in composite coal samples, lithotypes, and clay is represented by clay minerals (montmorillonite, kaolinite, illite), quartz, pyrite, and gypsum in various quantities. A total of 66 elements were measured in all samples. The measured concentrations were compared to worldwide values of brown coal and upper continental crust and coefficients of enrichment (K1 and K2, respectively) were established. Most of the studied critical elements (REY, platinum-group metals, Li, Si, Mg, Ge, Ga, Nb, Sb, In, Co, Be, W) have low concentrations (K1 and K2 &lt;2). The content of rare earth elements, yttrium, and scandium in the studied composite coal and lithotype samples is lower than concentration in world low-rank coal (65 ppm) and lower than in the studied black clay (145 ppm). The K1 and K2 coefficients of Pd and Pt, Te, Re, and Au are anomalously high. The mode of occurrence of most trace elements is mineral matter (sorbed in clay minerals, trace elements in pyrite, and as discrete phases). Some elements in low-ash samples (lithotypes) demonstrate affinity to organic matter: Te, Re, As, Mo, Ca, P, Au, Ba, Sr, Cd, etc. The lithotypes show enrichment in HREE (Gd–Lu) and Y in the following decreasing order: xylain &gt; fusain ≫ liptain. The anomalously high contents of Te, Re, Pd, Pt, Au, Se, As, Mo, and others require further investigation.

Enhanced room temperature fracture toughness of directionally solidified Nbss/Nb5Si3 in situ composites via Rhenium addition

Using directional solidification technique, a series of Nb–Si in situ composites with nominal compositions of Nb–16Si–23Ti–4Cr–2Al-2Hf-xRe (x = 0, 0.1, 0.4, 0.6, at.%) were manufactured to investigate the phase constituent, microstructural evolution and room temperature fracture toughness. These four different alloys all consisted of Nbss, αNb5Si3 and γNb5Si3, while Rhenium was primarily partitioned in Nbss matrix. With further addition content of Re, the silicide got refinement firstly, its average size minimized to 4.68 μm in 0.4Re alloy; but that coarsened again in 0.6Re alloy which resulting in the maximum micro-hardness of 1627 HV. The ductile Nbss matrix in 0.4Re alloy exhibited best continuity and its volume fraction rose to 63.1%; that triggered more obvious microcrack, fracture step and crack bifurcation, especially interface decohesion during loading process, thus increasing the room temperature fracture toughness from 8.4 MPa m1/2 to 13.1 MPa m1/2. But the 0.6Re alloy had an adverse effect on room temperature plasticity due to higher proportion and larger size of silicide, then exerted perceptible constraint for ductile Nbss matrix. In order to better optimize the mechanical performance of Nb–Si based alloys, the alloying amount of Rhenium should be properly selected to circumvent its concentration-sensitive effect.

Development of a novel unified quality control strategy for proprietary Chinese medicines

There is no effective method for unified quality evaluation for the same medicinal materials in similar prescriptions. In this study, we used Ginseng-Fuzi ( Aconitum carmichaelii ) proprietary Chinese medicines (GFPCMs), with different dosage forms, as examples to develop a new unified quality control strategy. Thus, using a high performance liquid chromatography-tandem mass spectrometry method, coupled with unified quality evaluation strategies to comprehensively characterize the contents of 12 aconitines and 25 ginsenosides containing eight groups of isomers in 10 GFPCMs. Quality control was carried out for the first time for aconitines and ginsenosides in Jianbuqiangshen Pill, Nanbao Capsule, Nvbao Capsule, Pingfengshengmai Capsule, Wumei Pill, and Xinbao Pill. Furthermore, 4 aconitines and 16 ginsenosides were firstly quantified in all 10 GFPCMs. Subsequently, there was a comprehensive comparison of the universality and accuracy of the quality control strategies based on absolute, normalized, and unit content. It was indicated the strategy-based unit content was more practical and effective. As for Fuzi, the total unit content of diester alkaloids should be less than 0.020%, while monoester alkaloids should be more than 0.010%. As for ginseng, the total unit content of Rb1, Rb2, Rc, Rg5, and Re should be higher than 2.0%, and the unit content of Rg5 was a good indicator for the classification of the dosage forms and processing methods. In summary, this strategy showed great potential for supervising the quality of Chinese medicine.

Strengthening mechanism of cemented carbide containing Re

In the present study, the microstructural changes of WC hard phase, phase transition of Cobalt (Co) in the binder and grain boundary characteristics were investigated to interpret the strengthening mechanism of the cemented carbides containing Rhenium (Re). As the content of Re increased, the mean grain size of WC decreased from 0.95 μm to 0.43 μm. Re promoted the martensite transition of Co phase from face-centred cubic structure (fcc) to close-packed hexagonal structure (hcp) by lowering the stack fault energies, which stabilized the hcp-Co. Meanwhile, the addition of Re weakened the concentration of textures {0001}, which indicated the preferred textures {0001} disappeared and promoted the isotropy of WC grains. The number of special grain boundaries (especially the big angle grain boundaries and coincidence site lattice (Σ = 2)) increased obviously after Re addition. With the increase of Re content, hardness and transverse rupture strength (TRS) rose rapidly. Cemented carbide with 6 wt% Re displayed the topmost hardness of 1648.4 HV30 and TRS of 3690 MPa. The wear rate of cemented carbide with 6 wt% Re was approximately one-fifth of cemented carbide without Re addition. The excellent hardness, TRS and wear resistance of the cemented carbides were attributed to the Re induced synergistic strengthening effect of grain refinement, phase transition and formation of special grain boundaries.

Effects of combined infrared and hot-air drying on ginsenosides and drying characteristics of Panax notoginseng (Araliaceae) roots

Exploring new drying technology can help to deal with the challenge of better preservation of rhizome medicinal materials in the traditional Chinese medicine industry. In current work, combined infrared and hot-air drying (IR-HAD) was employed to Panax notoginseng roots and its effect on drying kinetics, energy efficiency and quality, i.e., rehydration ratio (RR), color parameters (L*, a*, b*), total color difference (∆E), Panax notoginseng saponins (PNS) content, and ginsenosides content (R1, Rg1, Re, Rd, Rb1) were evaluated. Hot air drying (HAD) was used as the control. Results showed that the increase in drying temperature significantly shortened drying time and reduced energy consumption. The shortest drying time of 43.0 h and lowest specific energy consumption of 15.9 kW·h/(kg-water) were obtained by IR-HAD at 55°C. The decrease of radiation distance and the increase of radiation power led to the shortening of drying time. However, high drying temperature resulted in large ΔE values, large collapse structure, and RR of samples. The drying time of Panax notoginseng roots dried by IR-HAD at a drying temperature of 50°C was shorter (15.5%) than HAD dried at the same drying temperature. The contents of R1, Rg1, Re, Rb1, and PNS were higher when the samples were dried by IR-HAD than those dried by HAD at the same temperature of 50°C. Moreover, the IR-HAD dried samples shortened 15.5% drying time and saved 22.1% energy consumption compared with HAD. Therefore, the optimal process condition was Panax notoginseng roots under IR-HAD at drying temperature of 50°C, radiation distance of 12 cm and radiation power of 1350 W, which can shorten drying time, maintain high ginsenosides contents and satisfactory apparent qualities. Keywords: Panax notoginseng (Burk.) F. H. Chen (Araliaceae) roots, infrared and hot air drying, drying kinetics, energy consumption, quality DOI: 10.25165/j.ijabe.20221501.6210 Citation: Jiang D L, Zheng Z A. Effects of combined infrared and hot-air drying on ginsenosides and drying characteristics of Panax notoginseng (Araliaceae) roots. Int J Agric & Biol Eng, 2022; 15(1): 267–276.

The synergistic effect of Re and W on the evolution of TCP phases in Nickel-based superalloys

In this work, the synergistic effect of Re and W on the evolution of the topological close-packed phases (TCP) in Nickel-based superalloys were studied by means of Thermo-Calculation (TC), solidifying slowly, Differential Thermal Analysis (DTA), and solution-aging treatment. The specimens were analyzed by means of SEM-EDS, TEM-SADP, and EPMA. The calculated results indicated that the P phase precipitated prior to the μ phase with the temperature decrease, and both phases μ and P coexisted in a certain temperature range when the content of Re was higher ( Re: 5–7 wt%) and the content of W was lower ( W:4–6 wt%); Only phase μ precipitated from the alloy when Re content was less than 4 wt% and W content was higher than 7 wt%. The experimental results showed that the μ phases were slats-like and distributed in parallel in different orientations; and the μ/P intergrowth phases with coherent relationship were short rod-like. In addition, the gathered μ/P intergrowth phases around the big blocky-like γ' phases were found in alloys solidified slowly, which was prone to cause holes. Based on phase-transition temperature obtained by combining calculation and DTA, the solution-aging process of the alloys were determined. After solution-aging treatment, the long strip shape μ phases and short rod-like μ/P intergrowth phases distributed uniformly in the matrix, and the big blocky-like γ' phases and holes disappeared. The experimental results showed that the total amount of TCP phase decreased and the P phase gradually disappeared when the content of Re decreased and the content of W increased. The research results had a guiding role in optimizing the composition of alloys and predicting the safety performance of aerocraft during the flight cycle.

Molecular differentiation of Panax notoginseng grown under different conditions by internal extractive electrospray ionization mass spectrometry and multivariate analysis

Panax notoginseng is a highly valuable and widely used herb in traditional Chinese medicine. The quality and efficacy of Panax notoginseng grown under different conditions can greatly vary due to the differences in chemical composition. The analysis of chemical composition in Panax notoginseng typically involves various experimental steps including extraction, chromatographic separation and characterization, which can be time- and labor-consuming. Therefore, the efficient quality assessment and control of Panax notoginseng requires the development of more rapid methods for the chemical characterization and classification of Panax notoginseng. In this study, a method based on internal extractive electrospray ionization mass spectrometry (iEESI-MS) was developed to characterize chemical components of Panax notoginseng samples under different growth conditions (e.g., place of origin, soil quality, growth season) at the speed of 0.5 min per sample, without sample pretreatment and chromatographic separation. A total of 35 chemical components, including sugars, saponins, organic acids, etc., were identified in Panax notoginseng samples. Clear separation was observed in the multivariate analysis of the iEESI-MS data from Panax notoginseng samples grown under different conditions. The difference in the content of sucrose, fructose, Rg1, Rf, Rb1, Noto-R1, malonyl-Rb1, malonyl-Rg1, malonyl-Rf, Rd, Re, linoleic acid, palmitic acid and malic acid can be used as key characteristic indicators to discriminate origin, commercial specifications, and cultivation conditions of Panax notoginseng samples. The results of our study indicate the high power of iEESI-MS for the rapid molecular characterization and classification of Panax notoginseng under different growth conditions, which can be used for the quality assessment of traditional herbal medicines as well as in pharmaceutical and clinical analysis.