Effects of Aging Treatment on the Microstructures and Mechanical Properties of a TC18 Alloy.

In the present work, the effects of aging treatment on the microstructures of a TC18 alloy are studied. The influence of aging treatment on the tensile properties and failure mechanisms is systematically analyzed. It is found that the size and morphology of the primary α (αp) phases are insensitive to aging temperature and time. Furthermore, the aging temperature and time dramatically influence the precipitation of the secondary α (αs) phases. Massive αs phases precipitate and gradually coarsen, and finally weave together by increasing the aging temperature or extending the aging time. The variations in αp and αs phases induced by aging parameters also affect the mechanical properties. Both yield strength (YS) and ultimate tensile strength (UTS) first increase and then decrease by increasing the aging temperature and time, while ductility first decreases and then increases. There is an excellent balance between the strengths and ductility. When the aging temperature is changed from 450 to 550 °C, YS varies from 1238.6 to 1381.6 MPa, UTS varies from 1363.2 to 1516.8 MPa, and the moderate elongation ranges from 9.0% to 10.3%. These results reveal that the thickness of αs phases is responsible for material strengths, while the content of α phases can enhance material ductility. The ductile characteristics of the alloy with coarser αs phases are more obvious than those with thinner αs phases. Therefore, the aging treatment is helpful for the precipitation and homogeneous distribution of αs phases, which are essential for balancing the strengths and ductility of the studied Ti alloy.

Two new species of Polyalthiopsis (Annonaceae) based on morphological characters and phylogenetic evidence, with a supplementary description of P. chinensis from China.

Two new species of Polyalthiopsis (Annonaceae), P. nigra Y.H. Tan & Bin Yang from Guangxi and Yunnan Provinces and P. xui Y.H. Tan & Bin Yang from Yunnan Province, are described and illustrated. P. nigra is morphologically similar to P. chinensis in having narrowly elliptic-oblong, lemon to yellowish green petals, but differs by having obovoid monocarps, a higher number of leaf secondary veins, leaf blades usually widest above the middle, and a lower ratio of leaf blade length to width. P. xui is morphologically similar to P. floribunda in having axillary inflorescences, 1-3(-4) flowers, elliptic leaves, and elliptic-ovate petals, but differs in the numbers of carpels per flower and ovules per carpel. The molecular phylogenetic analysis using five plastid markers confirm that the two new species belong to the genus Polyalthiopsis and show clear interspecific divergences between P. nigra and P. xui and between them and other species in the genus. Detailed descriptions, colored photographs, and habitat and distribution data for the two new species are provided. In addition, the fruit morphology of P. chinensis is described for the first time, based on living collections. Geographical distributions and a diagnostic key for all Polyalthiopsis species are also presented.

Oreocharispolyneura, a new species of Gesneriaceae from southern Yunnan, China.

Oreocharispolyneura, a new species from southern Yunnan, China, is described and illustrated. It is morphologically similar to O.rhytidophylla by having more obvious lateral veins forming a crosslinked network on the adaxial surface of leaf blades, but can be distinguished by having more lateral veins (12-15 pairs vs. 7-9 pairs) of leaf blades, shorter corolla tubes (the length ratio of corolla tube to corolla lobes = 1.2-2.9 vs. 3.4-6) and shorter pistils (6-8 mm long vs. 27-30 mm long). In addition, a detailed morphological description, a photographic illustration, the distribution and phenology of the new species are presented.

Contributions to the flora of Myanmar from 2000 to 2019.

Myanmar is botanically rich and floristically diverse: one of the world's biodiversity hotspots. However, Myanmar is still very unevenly explored, and until a plant checklist was published in 2003, relatively little work was done on its flora. This checklist included 11,800 species of spermatophytes in 273 families. Since this checklist was published, the botanical exploration of Myanmar has accelerated and there have been many additional publications. We therefore surveyed the literature of taxonomic contributions to Myanmar's vascular flora over the last 20 years (2000-2019) and compiled a list of new and newly described taxa. Our list includes 13 genera, 193 species, 7 subspecies, 19 varieties, and 2 forms new to science; and 3 families, 34 genera, 347 species, 4 subspecies, 7 varieties, and 1 form newly recorded in Myanmar. Altogether, they represent 91 families and 320 genera. Most of the new discoveries belong to 15 families, with more than 25% (146 taxa) belonging to Orchidaceae. These new discoveries are unevenly distributed in the country, with about 41% of the newly discovered species described from Kachin State in northeast Myanmar. This reflects the incompleteness of our current knowledge of the flora of Myanmar and the urgent need for a greatly expanded effort. The completion of the flora of Myanmar requires more fieldwork from north to south, taxonomic studies on new and existing collections, and some mechanism that both coordinates the efforts of various international institutions and initiatives and encourages continued international cooperation. In addition, producing modern taxonomic treatments of the flora of Myanmar requires the participation of experts on all vascular plant families and genera. There is also an urgent need to attract young scientists to plant taxonomy, to work on inventories, identification, nomenclature, herbarium work, and comparative studies.

From Polyalthia to Polyalthiopsis (Annonaceae): transfer of species enlarges a previously monotypic genus.

The genus Polyalthiopsis Chaowasku (Annonaceae) was a poorly known monotypic genus from Vietnam that was recently segregated from the highly polyphyletic genus Polyalthia s.l. The sister clade relationship between Polyalthiopsis and Miliusa was not well established in previous study. The phylogenetic position of two Polyalthia spp. from China, P. chinensis S.K.Wu ex P.T.Li and P. verrucipes C.Y.Wu ex P.T.Li, remains unresolved and is shown here to be phylogenetically affiliated with Polyalthiopsis. Phylogenetic analyses of six chloroplast regions (matK, ndhF, psbA-trnH, rbcL, trnL-F and ycf1; ca.7.3 kb, 60 accessions) unambiguously placed Polyalthia chinensis and P. verrucipes in the same clade with Polyalthiopsis floribunda (PP = 1, MPBS = 97%); the entire clade is sister to Miliusa with weak to strong support (PP = 1, MPBS = 54%). Polyalthia chinensis and P. verrucipes share several diagnostic characters with Polyalthiopsis floribunda, including the raised midrib on the upper surface of the leaf in vivo, conspicuous foliar glands when dried, petiole with transverse striations when dried and axillary inflorescences. The two species differ from Polyalthiopsis floribunda in having fewer flowers per inflorescence, longer linear petals and two ovules per carpel. On the basis of the combined molecular phylogenetic and morphological data, we propose two new combinations, Polyalthiopsis chinensis (S.K.Wu ex P.T.Li) B.Xue & Y.H.Tan and Polyalthiopsis verrucipes (C.Y.Wu ex P.T.Li) B.Xue & Y.H.Tan. The protologue of Polyalthia verrucipes did not include a description of the flowers, which we provide here. An updated description for the genus Polyalthiopsis and a key to species in the genus Polyalthiopsis is also provided.

A new species and two new records of Goniothalamus (Annonaceae) from Lao PDR.

Goniothalamus saccopetaloides Y.H. Tan & Bin Yang, a new species is described and illustrated from Laos. This species shows morphological similarities to G. yunnanensis W.T. Wang, but it differs from the latter by having almost fleshy, involute and saccate outer petals, subglobose monocarps, and single seeded monocarps. Goniothalamus cheliensis, and G. calvicarpus are new records for the Flora of Lao PDR. A key to Goniothalamus species indigenous to Laos is provided here.

Taxonomic studies on Amomum Roxburgh s.l. (Zingiberaceae) in Myanmar II: one new species and five new records for the flora of Myanmar.

In the course of a study of Amomum s.l. (Zingiberaceae) in Myanmar, Amomum schistocalyx Y.H. Tan & H.B. Ding, from Htamanti Wildlife Sanctuary, Sangaing Region of Northern Myanmar is described and illustrated as new to science here. Five taxa: A. yingjiangense S.Q. Tong & Y.M. Xia, A. carnosum V.P. Thomas & M. Sabu, A. tibeticum (T.L. Wu & S.J. Chen) X.E. Ye, L. Bai & N.H. Xia, Lanxangia scarlatina (H.T. Tsai & P.S. Chen) M.F. Newman & Skornick, and Meistera yunnanensis (S.Q. Tong) Skornick. & M.F. Newman, are newly recorded from Myanmar. The photographic illustrations, the distributions, and voucher specimens for each species are provided.

A new species and two new combinations of Monolophus (Zingiberaceae) from Indo-Burma.

Monolophus odontochilus Y.H.Tan & H.B.Ding, a new species from Northern Myanmar, is described and illustrated. The new species is morphologically similar to M. linearis, but differs by having elliptic to oblong leaves (vs. linear-lanceolate to lanceolate), bilobed ligules (vs. entire), purely white corolla (vs. pinkish white), semi-orbicular crenate labellum (vs. trilobed). In addition, a diagnostic key to the new species of Monolophus and its closely related non-yellow flowered species is provided. New combinations are proposed here for Caulokaempferia phokhamii Picheans. & Douangde. and C. wongsuwaniae Picheans. & Douangde. from Laos.

An updated checklist of Begonia (Begoniaceae) in Laos, with two new species and five new records.

Two new species of Begonia L. (Begoniaceae), B. laotica (sect. Parvibegonia) and B. hypoleuca (sect. Reichenheimia), from north Laos are described and illustrated. Begonia augustinei, B. dryadis, B. lancangensis, B. sizemoreae and B. sillentensis subsp. mengyangensis were newly recorded taxa in Laos. Furthermore, an updated checklist of Begonia of Laos is also compiled.

Taxonomic studies on Begonia (Begoniaceae) in Myanmar I: three new species and supplementary description of Begonia rheophytica from Northern Myanmar.

Three new species of Begonia (B. chenii, B. putaoensis and B. crassitepala) belonging to Begonia section Platycentrum and a supplementary description of B. rheophytica with a detailed description of female flowers from Putao, Kachin State, Northern Myanmar, are described and illustrated. All the new species are endemic to Northern Myanmar and can be easily distinguished from other species among the section Platycentrum. A detailed description, photographs, habitat, distribution and a comparison with the most related allied species for all new species are provided.

Four new species of Gesneriaceae from Yunnan, Southwest China.

Four new species of Gesneriaceae from Yunnan, southwest China, are described and illustrated. They are Petrocosmea rhombifolia, Petrocosmea tsaii, Didymocarpus brevipedunculatus, and Henckelia xinpingensis. Diagnostic characters between the new species and their morphologically close relatives are provided. Their distribution, ecology, phenology, and conservation status are also described.

New contributions to the flora of Myanmar â .

In this study, we describe several new taxa belonging to the flora of Myanmar. One new family, Polyosmaceae (Polyosma wallichii Benn.) is recorded. Over ten new genera are recorded for the first time, including Amentotaxus Pilger (Taxaceae), Hydrobryopsis Engler (Podostemaceae), Cyrtosia Blume and Biermannia King & Pantling (Orchidaceae), Eleutharrhena Forman and Haematocarpus Miers (Menispermaceae), Craigia W.W. Smith & W.E. Evans (Malvaceae), Amblyanthopsis Mez (Primulaceae), Huodendron Rehder and Rehderodendron Hu (Styracaceae), Platea Blume (Metteniusaceae), Achyrospermum Blume (Lamiaceae), Christisonia Gardner (Orobanchaceae). In addition, five new species are described and illustrated: Tupistra natmataungensis Y.H. Tan & H.B. Ding, Biermannia burmanica Y.H. Tan & Bin Yang, Impatiens megacalyx Y.H. Tan & H.B. Ding, Amblyanthopsis burmanica Y.H. Tan & H.B. Ding, Platea kachinensis Y.H. Tan & H.B. Ding. The distribution, ecology, phenology, and conservation status of these new species are also described.

Two new species of Hiptage (Malpighiaceae) from Yunnan, Southwest of China.

Hiptagepauciflora Y.H. Tan & Bin Yang and Hiptageferruginea Y.H. Tan & Bin Yang, two new species of Malpighiaceae from Yunnan, South-western China are here described and illustrated. Morphologically, H.pauciflora Y.H. Tan & Bin Yang is similar to H.benghalensis (L.) Kurz and H.multiflora F.N. Wei; H.ferruginea Y.H. Tan & Bin Yang is similar to H.calcicola Sirirugsa. The major differences amongst these species are outlined and discussed. A diagnostic key to the two new species of Hiptage and their closely related species is provided.

Two new species of Trivalvaria (Annonaceae) from northern Myanmar.

Trivalvaria rubra and Trivalvaria casseabriae, two new species of Annonaceae from Putao, Kachin State, Myanmar, are here described and illustrated. They are morphologically similar to T. costata and T. macrophylla. The major differences between them are outlined and discussed. A diagnostic key to the species of Trivalvaria is provided.

Aristolochia sinoburmanica (Aristolochiaceae), a new species from north Myanmar.

Aristolochia sinoburmanica Y.H.Tan & B.Yang, a new species of Aristolochiaceae from Putao, Kachin State, Myanmar, is described and illustrated. According to morphology (strongly curved perianth, 3-lobed limb, as well as 3-lobed gynostemium, anthers 6, adnate in 3 pairs to the base of gynostemium, opposite to the lobes), the species belongs to Aristolochia subgenus Siphisia. It is morphologically similar to A. faviogonzalezii, A. hainanensis, A. tonkinensis, A. saccata and A. xuanlienensis. The major differences between them are outlined and discussed. A detailed description, along with line drawings, photographs, habitat, distribution and conservation status, as well as a comparison to morphologically similar species, are also provided.

Hedychium putaoense (Zingiberaceae), a new species from Putao, Kachin State, Northern Myanmar.

Hedychium putaoense Y.H. Tan & H.B. Ding, a new species of Zingiberaceae from Putao, Kachin state, Northern Myanmar, is described and illustrated. It is similar to H. densiflorum Wall. and H. longipedunculatum A.R.K. Sastry & D.M. Verma, but differs by its very small bract (4-6 × 2.5-3 mm vs. 18-19 × 5-5.5 mm and ca. 11 × 7 mm, respectively), semicircle and dark red bracteole, orange flower and broadly falcate to lanceolate lateral staminodes.

[Impacts of human disturbance on the species composition of higher plants in the wetlands around Dianchi Lake, Yunnan Province of Southwest China].

Introducing higher plants to build semi-natural wetland ecosystem is one of the key approaches to restore the wetlands and lakes that suffered from serious pollution and destruction. Based on the investigation data from 128 quadrats at 26 sampling sites in the wetlands around Dianchi Lake in December 2011-October 2012, and in combining with the references published in the 1960s, this paper discussed the impacts of human activities on the species composition of higher plants in the wetlands around the Lake. In 2012, there were 299 species of 88 families in the wetlands, of which, 181 species were native species, and 118 species were alien ones (including 32 invasive species). Of the 42 species of hydrophytes in the total species, 13 species were alien ones (including 2 invasive species). In comparing with the species data recorded in the 1960s, 232 plants were newly recorded and 43 species disappeared in 2012. Aquatic plants changed obviously. The decreased species were 2 submerged plants, 2 floating plants, and 5 floating leaved plants, and the increased species were 8 emergent plants. Fourteen community types were identified by cluster analysis, of which, the main communities were those dominated by alien species including Pistia stratiotes and Alternanthera philoxeroides. As compared with the data in the 1960s, the plant communities dominated by native species such as Ottelia acuminate and Vallisneria natans were not found presently. Therefore, in the practice of introducing higher plants to restore the degraded wetlands and lakes, it would be necessary to scientifically and appropriately select and blend plant species to avoid the wetland degradation by human activities.

Caproate formation in mixed-culture fermentative hydrogen production.

Caproate always appears during fermentative H(2) production but its formation was not well explained. It possibly results from the secondary fermentation of ethanol and acetate or butyrate by some special species like Clostridium kluyveri. This study attempts to elucidate caproate formation during the fermentation H(2) production by using C. kluyveri as an example and evaluating several possible pathways of caproate formation. A detailed energetic analysis of the empirical data of an H(2)-producing reactor demonstrated that caproate can be formed from two substrates, either ethanol and acetate or ethanol and butyrate. The analysis showed that at least 5 mol ethanol per mole reaction was essential to support caproate formation under the experimental condition. The analysis also indicated that the secondary fermentation by C. kluyveri might be another pathway to spontaneously produce H(2), butyrate, and acetate in addition to the butyrate-acetate pathway. Co-production of caproate and H(2) from ethanol was thermodynamically feasible and contributed to at least 10-20% of total H(2) production in the reactor studied. It is also clarified that caproate formation is hydrogenogenic rather than hydrogenotrophic.

Biotechnology for aerobic conversion of food waste into organic fertilizer.

A biotechnology for aerobic conversion of food waste into organic fertilizer under controlled aeration, stirring, pH and temperature at 55-65 degrees C, is proposed. To maintain neutral pH at the beginning of the bioconversion 5% CaCO3 was added to the total solids of the food waste. The addition of 20% horticultural waste compost as a bulking agent to the food wastes (w.w./w.w.), improved the bioconversion and increased the stability of the final product. No starter culture was needed for aerobic bioconversion of food waste into organic fertilizer for 10 days. The low contents of heavy metals in the raw materials used in the bioconversions ensured the safety of fertilizer from food waste for application in agriculture. The addition of 4% organic fertilizer to the subsoil increased the yield and growth of Ipomoea aquatica (Kang Kong) by 1.5 to 2 times. The addition of phosphorus is required to enhance the positive effect of organic fertilizer on plant growth.

Biotransformation of vegetable and fruit processing wastes into yeast biomass enriched with selenium.

Water extracts of cabbage, watermelon, a mixture of residual biomass of green salads and tropical fruits were used for yeast cultivation. These extracts contained from 1420 to 8900 mg/l of dissolved organic matter, and from 600 to 1800 mg/l of nitrogen. pH of the extracts was in the range from 4.1 to 6.4. Biomass concentration of yeast, Saccharomyces cerevisiae CEE 12 grown at 30 degrees C for 96 h in the sterilized extracts without any nutrient supplements was from 6.4 to 8.2 g/l; content of protein was from 40% to 45% of dry biomass. The yield was comparable with the yield of yeast biomass grown in potato dextrose broth. The biomass can be considered as the protein source. Its feed value was enhanced by incorporation of selenium in biomass to the level of 150 microg/g of dry biomass. Therefore, it was recommended to transform the extracts from vegetable and fruit processing wastes into the yeast biomass enriched with selenium.