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Three compositions of Ag-Cu-In-Ti system brazing alloys were designed for joining SiO 2f /SiO 2 ceramic composite to Nb metal. The wettability of the three alloys on the composite was studied with the sessile drop method. The results showed that after heating at 1073 K for 30 min, they exhibited contact angles of 74°, 83° and 86°, respectively. The brazing alloys were fabricated into foils by rapid solidification technique. Among the three brazing filler alloys the joints brazed with AgCu-10In-5Ti at 1073 K for 10 min presented the maximum average shear strength of 30.9 MPa. During the brazing process the active element Ti diffused strongly from the filler alloy to the composite surface and a reaction layer with a thickness of 2–3 μm was formed. Sound metallurgical bonding was also achieved at the Nb side. The interface structure of the joint brazed with the AgCu-10In-5Ti alloy can be described as the following sequence: SiO 2f /SiO 2 →SiO 2 +Cu 3 Ti 3 O→SiO 2 +TiO+Ti 5 Si 4 →Ag(s, s)+(Cu-Ti)→Nb. However, for the filler alloy with 4.0 wt% Ti content the joint strength was only 15.8 MPa. [ABSTRACT FROM AUTHOR]

Jaboticaba (Myrciaria cauliflora) and false jaboticaba (Myrciaria vexator) fruits are two pleasant-tasting, dark-colored fruits, native to Brazil. They are rich sources of phenolic compounds, including anthocyanins, flavonoids, phenolic acids, and tannins, as well as less well known polyphenols such as depsides. These two fruits are very similar in morphology, but their taste profiles differ markedly. This study was focused on identifying the marker compounds between them using HPLC-PDA and LC-TOF-MS, combined with principal component analysis. As a result, cyanidin-3-O-glucoside was found as the major anthocyanin in Myrciariafruits. Delphinidin-3-O-glucoside was found to be the marker compound for jaboticaba, while cyanidin-3-O-galactoside and cyanidin-3-O-arabinose were two marker compounds distinguishing false jaboticaba. In addition, two ellagitannins, iso-oenothein C and oenothein C, were isolated and identified from both of these fruits for the first time. Jaboticabin, a minor bioactive depside, occurred in both fruits and, because of its potential to treat chronic obstructive pulmonary disease, was successfully synthesized in the laboratory.

Myrciaria cauliflora(jaboticaba) is an edible fruit common in Brazil that has been used for treating respiratory diseases, including chronic tonsillitis and asthma. This study explores the distribution of an anti-inflammatory depside, jaboticabin, in different parts of the jaboticaba plant as well as major polyphenols from the wood of jaboticaba, some with biological activity similar to jaboticabin. The peel of the fruit was found to be the major source of jaboticabin. This is the first phytochemical study of the wood of M. cauliflora. The antioxidant-activity-guided fractionation strategy successfully identified 3,3′-dimethylellagic acid-4-O-sulfate from jaboticaba wood. This ellagic acid derivative, in a manner similar to jaboticabin, showed antiradical activity and inhibited the production of the chemokine interleukin-8 after treating the human small airway epithelial cells with cigarette smoke extract. The human intestinal Caco-2 cell studies demonstrated the jaboticabin transport in vitro. The polyphenols, jaboticabin and 3,3′-dimethyellagic acid-4-O-sulfate, from jaboticaba were both found to exhibit anti-inflammatory activities, thus suggesting the potential use of these compounds or even the fruits themselves for chronic obstructive pulmonary disease.

SiO2f/SiO2composite was joined to Al2O3ceramic using AgCu-Ti active filler at brazing temperature of 1153 K for 10 and 60 min, respectively, and sound joints were achieved. It was found that a thin reaction layer had been formed close to each of the joined materials, and the brazing seam matrix was composed of homogeneous Ag-Cu eutectic alloy. The joint interface was analyzed by SEM, EDS, and XRD. The typical interface structure of joint brazed at 1153 K for 10 min could be described as the following sequence: SiO2f/SiO2→ TiO2+ Ti5Si4→ TiO2+ Cu3Ti3O → Ag-Cu eutectic alloy → (Ti-O) + (Ti-Cu-O) → Al2O3. However, Cu2Ti4O but not Cu3Ti3O was detected in the joints brazed at 1153 K for 60 min. Besides, the reaction layers of joint brazed at 1153 K for 60 min were much thicker than those for 10 min. The SiO2f/SiO2-Al2O3joints brazed at 1153 K for 10 min showed an average shear strength of 38.6 MPa, evidently higher than that (26.0MPa) brazed at 1153 K for 60 min.

A number of Garciniaspecies accumulate benzophenone derivatives that may be useful for the treatment of breast cancer. The dereplication of new benzophenone derivatives from Garciniaspecies is challenging due to the occurrence of multiple isomers and the known compounds found in their extracts. In the current study, a strategy is described using the UPLC-QTOFMSEtechnique to identify tentatively the known and uncharacterized benzophenones of interest based upon the characteristic fragmentation ions. Several UPLC-QTOFMS peaks (a–ee) appeared to contain benzophenone derivatives, and 12 of these peaks contained compounds with MS ionization profiles not consistent with previously identified compounds from the seeds of Garcinia paucinervis, an endangered Chinese species. The targeted isolation of unidentified compounds of interest afforded five new benzophenones, paucinones E–I (1–5), which were determined by MS and NMR analysis and ECD spectroscopy. These compounds were evaluated for cytotoxicity against three breast cancer cell lines inclusive of MDA-MB-231, SKBR3, and MCF-7. These results indicate that the UPLC-QTOFMSE-guided isolation procedure is an efficient strategy for isolating new benzophenones from Garciniaspecies.

Eggplant and related Solanumspecies contain abundant caffeoylquinic acid (CQA) derivatives. Fruit of the invasive species Solanum viarumDunal contain numerous complex CQA derivatives, but only a few have been identified. The structures of two new compounds isolated from methanolic extracts of S. viarumfruit by C18-HPLC-DAD were determined using 2D NMR and MS data. Both include two 5-CQA molecules joined by glucose via ester and glycosidic linkages. The structures of compounds 1and 2(viarumacids A and B) are, respectively, 5-caffeoyl- and 3-malonyl-5-caffeoyl-[4-(1β-[6-(5-caffeoyl)quinate]glucopyranosyl)]quinic acid. The antioxidant activities determined by ABTS•+and DPPH•assays were in the order 1> 2> 5-CQA.

YVO4 nanoparticles with various morphologies were tuned directly by hydrothermal treatment in different solutions, including pure water, potassium hydroxide solution, hydrazine hydrate, ethanolamine, triethylamine, and pyridine. X-ray diffraction (XRD), Raman, and transmission electron microscopy (TEM) were utilized to characterize the structure, morphology, and size of the products, which indicated that tetragonal phase YVO4 crystallites displaying rod-like, square, and olivary shapes were obtained. It was found that the selected solvents play an important role in modulating the morphology and confining the size of the obtained products.

Ten new triterpenoids, named meliasenins I−R (1−10), one new steroid (11), and 11 related known compounds (12−22) were isolated from fruits of Melia toosendan. The structures of the new compounds were established on the basis of spectroscopic methods, including 2D NMR techniques and mass spectrometry. The relative configuration of 1, (20R*,23E)-25-hydroperoxyeupha-7,23-diene-3β,16β-diol (meliasenin I), was confirmed by single-crystal X-ray diffraction analysis. All isolated triterpenoids (1−10, 12−15) and two steroids (11, 20) were tested for their cytotoxicity against U20S human osteosarcoma and MCF-7 human breast cancer cells using the MTT assay, and some of them were significantly cytotoxic (IC50<10 μg/mL). The insecticidal properties of compounds 1−15and 20were also briefly evaluated.

A new dimeric psoralen-type furanocoumarin, notopterol-(18-O-20′)-notopol (1), was isolated from Notopterygium incisum for the first time and its structure was elucidated by spectroscopic methods.

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