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RumexL., a genus in Polygonaceae family with about 200 species, is growing widely around the world. Some Rumexspecies, called "sorrel" or "dock", have been used as food application and treatment of skin diseases and hemostasis after trauma by the local people of its growing areas for centuries. To date, 29 Rumexspecies have been studied to contain about 268 substances, including anthraquinones, flavonoids, naphthalenes, stilbenes, diterpene alkaloids, terpenes, lignans, and tannins. Crude extract of Rumexspp. and the pure isolates displayed various bioactivities, such as antibacterial, anti-inflammatory, antitumor, antioxidant, cardiovascular protection and antiaging activities. Rumexspecies have important potential to become a clinical medicinal source in future. This review covers research articles from 1900 to 2022, fetched from SciFinder, Web of Science, ResearchGate, CNKI and Google Scholar, using “Rumex” as a search term ("all fields") with no specific time frame set for the search. Thirty-five Rumexspecies were selected and summarized on their geographical distribution, edible parts, traditional uses, chemical research and pharmacological properties.

Purpose – Since the construction of China-ASEAN Free Trade Area (CAFTA) launched in 2002, the bilateral trade increased rapidly. The purpose of this paper is to test the competition and cooperation in trade relationships between China and the main trading partners (Singapore, Malaysia and Thailand (SMT)) from ASEAN in international trade under CAFTA. Design/methodology/approach – Grey Lotka-Volterra competition models are established for testing the trade relationships between China and SMT, respectively, based on the data of import and export from 2003 to 2014. To improve modeling accuracy, the interpolated coefficients for dynamic background value are introduced into the grey Lotka-Volterra model. The optimal parameters are solved through minimizing the mean absolute percentage error and the constraint of parameter relationships. Besides, eigenvalues of the Jacobian matrix are adopted to carry out the stability of equilibrium points of the trade relationships. Findings – As the beneficiary party, China has mutual benefit and win-win trade relationship with Singapore, while it has predator-prey trade relationships with Malaysia and Thailand. The future exports from SMT to China will stabilize at 462.31, 598.13 and 447.03 billion dollars, respectively. The future exports from China to SMT will stabilize at 637.16, 943.71 and 827.52 billion dollars, respectively. Practical implications – This study can be regarded as an important reference for China and its trading partners from ASEAN. The modeling results can help the decision makers to formulate appropriate international trade strategies to gain and maintain competitive advantages. Originality/value – A new approach to testing the trade relationships is proposed based on grey Lotka-Volterra competition model. The study also proposed a dynamic optimization method for the background value of grey Lotka-Volterra model. [ABSTRACT FROM AUTHOR]

The cutting performance, failure mechanisms and reliability of Al2O3/TiC micro-nanocomposite ceramic tools with different geometry parameters in continuous machining of austenitic stainless steel were studied. The results showed that the largest metal removal amount was got at the cutting speed of 80 m/min, the feed rate of 0.15 mm/r and the cutting depth of 0.1 mm. The failure modes of the tool with small chamfering width and corner radius were mainly cutting edge fracture and tool materials peeling off, which was due to the subcritical crack growth. The life of the tool with small chamfering width and corner radius well followed the Gamma distribution.

Micro milling is most flexible to create 3D features for application. However, how to design and fabrication of high precision micro milling tools are one of big challenges for mechanical micro milling. Commercially available micro milling tools are usually simply made from downsizing of macro milling tools, which have negative impact on milling performance. Therefore, in this paper, firstly, various structural of micro milling tools were optimized with abaqus that investigated stress and strain under certain static load on the cutting edges. Then, results showed the minimum stress and strain was a micro hexagonal end mill. Finally, a Ti (C7N3) cermet micro hexagonal end mill with a radius of 0.5mm was fabricated by wire electrical discharge machining, and the evaluation experiments for the hexagonal mill have been processed on a micro milling centre.

In order to fulfil the actual request of machining process to the machining database system, according to the characteristics and requirements of machining process, the fuzzy technology and case-based reasoning method were introduced to the design of machining database system. The reasoning process of case-based reasoning method and three main aspects of the fuzzy model were discussed. The match of cases and fuzzy comprehensive evaluation were introduced. The function of high-speed machining database was analyzed and the structure of the database was described. The users can use the database to acquire the overall solutions about high-speed machining.

Abrasive waterjet machining is considered as a promising technique in hard-brittle material polishing. In this paper, The ultrasonic torsional vibration is considered to apply on the workpiece to improve the abrasive waterjet polishing quality and efficiency. The process parameters in the ultrasonic torsional vibration-assisted abrasive waterjet polishing are optimized. The ultrasonic torsional vibration in the role of the abrasive waterjet polishing is investigated. The results show that the application of ultrasonic torsional vibration can effect of abrasive particle movement and increase the critical depth of the ceramic materials.

The roots of Panax notoginseng, an important Chinese medicinal plant, have been used traditionally in both the raw and processed forms, due to the different chemical constituents and bioactivities found. Thirty-eight dammarane-type triterpenoid saponins were isolated from the steam-processed roots of P. notoginseng, including 18 new substances, namely, notoginsenosides SP1–SP18 (1–18). The structures of 1–18were determined on the basis of spectroscopic analysis and acidic hydrolysis. The absolute configuration of the hydroxy group at C-24 in 1–4, 19, and 20was determined in each case by Mo2(AcO)4-induced circular dichroism. The new compounds were found to feature a diversity of highly oxygenated side chains, formed by hydrolysis of the C-20 sugar moiety followed by dehydration, dehydrogenation, epoxidation, hydroxylation, or methoxylation of the main saponins in the raw roots. The new saponins 1, 2, 6–8, 14, and 17and the known compounds 20–27showed promoting effects on the differentiation of PC12 cells, at a concentration of 10 μM.

“Long-Dan” and “Qin-Jiao” are two important TCM herbs since ancient times in China. In the Chinese Pharmacopoeia, the dried roots and rhizomes of four species from the genus Gentiana, e.g. Gentiana manshurica, G. scabra, G. trifloraand G. rigescens, are recorded under the name of Gentianae Radix et Rhizoma (“Long-Dan” in Chinese), while the other four species from the same genus including G. macrophylla, G. crassicaulis, G. stramineaand G. duhuricaare recorded and used as the raw materials of Gentianae Macrophyllae Radix (“Qin-Jiao” in Chinese). On the basis of the establishment of a validated HPLC–UV method for quantifying simultaneously, five iridoid glycosides, e.g. loganic acid (1), swertiamarinin (2), gentiopicroside (3), sweroside (4) and 2′-(o,m-dihydroxybenzyl)sweroside (5) have been used successfully as chemical markers for the comparison of the species used as “Long-Dan”, “Qin-Jiao” and their adulterants in the present study. The results suggested that four iridoid glycosides 1–4commonly existed in both “Long-Dan” and “Qin-Jiao”, while 2′-(o,m-dihydroxybenzyl)sweroside (5) also existed as one of the major components in “Dian-Long-Dan” species. Moreover, the contents of compounds 1–5were various in different “Long-Dan” and “Qin-Jiao” species. Herein, we profiled and compared three “Long-Dan” species, four “Qin-Jiao” species and five adulterants by applying multivariate statistical techniques to their HPLC data sets to establish the differences and/or similarities.

The TiB2 whiskers were fabricated in TiB2/TiCx composites by the in-situ synthesis process. The phase composition, thermodynamics, weight loss and lattice parameters of the obtained phases were studied. The obtained TiB2 whiskers showed an aspect ratio of 10-20 and a diameter of 0.5-1.5 μm. The synthesized TiC was a non-stoichiometric phase with a lattice parameter of 4.274 Å. Most of the whiskers had the cylinder shape, whereas, a few whiskers showed a bead-necklace morphology. The growth mechanisms of TiB2 whiskers were governed by the solid-liquid-solid (S-L-S) mechanism and the particle-to-particle connection mechanism.

Three new acylated flavonoid C-glycosides, 6‴-(-)-phaseoylspinosin (1), 6‴-(3″″,4″″,5″″-trimethoxyl)-(E)-cinnamoylspinosin (2), and 6‴-(4″″-O-β-D-gluco-pyranosyl)-benzoylspinosin (3), were isolated from the seeds of Ziziphus mauritiana(Rhamnaceae). A further 19 known compounds including eight spinosin analogues (4–11) were also isolated. Their structures were elucidated by means of spectroscopic analysis and chemical method. Among spinosin derivatives 1, 2, 4, 7, 8, and triterpenoid saponin 14, jujuboside A (14) displayed moderate acetylcholinesterase (AchE) inhibitory activity with an inhibition value of 46.2% at a concentration of 1 µM.

Three kinds of Al2O3 ceramics matrix composites, such as Al2O3-TiB2, Al2O3-SiC and Al2O3-TiC, were prepared by two steps, which were synthesis of the composites by thermal explosion under a pressure of 20MPa and hot pressing of the composites at 1700°C under a pressure of 32MPa respectively. The preparation process, the composition and the microstructure of the composites were investigated in detail. The Gibbs free energy and the adiabatic temperature (Tad) of three exothermic synthesis reactions were calculated. Disc-shaped and elongated TiB2 grains were synthesized in the Al2O3-TiB2 composite. Some whiskers and platelet grains were synthesized in the Al2O3-SiC composite. Nano-particles were synthesized in the Al2O3-TiC composite and distributed both within the Al2O3 matrix grains and along the grain boundaries.

Chemical study on the roots of Gentiana crassicaulisDuthie ex Burk (Gentianaceae) afforded 15 compounds, including two new iridoid glycosides, qinjiaosides B (1) and C (2). Their structures were elucidated by spectroscopic methods and chemical evidence. The isolated iridoid glycosides 1, 4–6and 8–11were tested for their anti-inflammatory activity by the inhibitory effects on LPS-induced NO and TNF-αproduction in macrophage RAW264.7 cells. All of them showed inhibitory effects on inflammatory mediators NO at a concentration of 15 µM, while 5and 9displayed the most potential inhibitory effects on TNF-αwith IC50 of 0.06 and 0.05 µM, respectively. The structure-activity relationships (SARs) of these iridoid derivatives were discussed.

TiB2-(W,Ti)C composites with (Ni,Mo) as sintering additive have been fabricated by hot-pressing technique, and the microstructure and mechanical properties of the composites have been investigated. (Ni,Mo) promotes grain growth of the composites. In the case of 7vol.% (Ni,Mo), the grain size decreases consistently with an increase in the content of (W,Ti)C. When the proper content of (W,Ti)C is added to TiB2 composites, the growth of matrix grains is inhibited and the mechanical properties of the composites are improved. The best mechanical properties of the composites are 1084.13MPa for three-point flexural strength, 7.80MPa•m 1/2 for fracture toughness and 17.92GPa for Vickers hardness.