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Investigation of phytoplankton from East China Sea of the Pacific Ocean, offshore Réunion Island of the Indian Ocean, and the French Atlantic coast revealed a species of poorly known armored fusiform dinoflagellate. To clarify this species, morphology and phylogeny based on mitochondrial and nuclear protein gene sequence (Cox1, Cob and Hsp90) concatenated with the SSU, ITS region and LSU rDNA sequences were analysed. Epifluorescence and scanning electron microscopy observations revealed that the nucleus of the specimen was elongated, sausage-shaped and located equatorially on the left lateral side of the cell, and that the plate formula is Po, 3′, 1a, 6″, 6C, 8S, 5‴, 1p, 2′‴. These morphological features indicate that the species can be assigned to Centrodinium punctatum. Interestingly, the phylogenetic analyses placed this species within the Alexandrium clade, with Alexandrium affine being its closest relative. This indicates that genus Alexandrium is not monophyletic. The most similar morphological traits between C. punctatum and Alexandrium species were the shape of apical pore plate and the arrangement of the sulcal plates. However, since there are significant morphological differences between C. punctatum and Alexandrium species, further studies are needed to clarify the relation between the morphology and molecular phylogeny of other Centrodinium -related fusiform species. [ABSTRACT FROM AUTHOR]

• A new transversal heat transfer channel structure was first proposed here. • The structure can quickly transfer heat accumulated in asphalt pavement to road shoulders. • Transverse thermal conductivity of asphalt mixtures is significantly improved. • The structure provides a new method for active cooling of asphalt pavement. On the Qinghai-Tibet Plateau, intense solar irradiation will cause serious heat accumulation in asphalt pavement. Downward heat transfer will disturb the permafrost under subgrade, thus leading to a series of subgrade and pavement diseases. This makes construction of asphalt pavement in the permafrost regions of the Qinghai-Tibet Plateau a world-class challenge. This paper proposes for the first time a transversal heat transfer channel in asphalt pavement, which can quickly transfer heat accumulated in pavement to road shoulders. Finite element software ABAQUS was used to simulate the rutting plate with high axial thermal conductivity carbon fibers inserted transversely. Under the constant heat load of 500 W / m 2 , the heat flux near the carbon fibers showed the characteristic of convergence. The maximum transverse heat flux in the carbon fibers reached 4.97 × 10 7 W / m 2 , which was 14 times that in the asphalt mixture. Meanwhile, the maximum vertical heat flux in the carbon fibers reduced to 2.62 × 10 6 W / m 2 , which was 12 % less than the asphalt mixture. The effective thermal conductivity of composite specimens with different carbon fiber parameters was studied through control experiments. When the axial thermal conductivity, volume fraction and number of carbon fiber bundles increased to 100 W / m · ° C , 10.72 % and 4 bundles respectively, the transverse ETC of composite specimens increased to 4.05 W / m · ° C , 7.09 W / m · ° C and 16.18 W / m · ° C respectively. They were 3.12 times, 5.45 times and 12.45 times of the control group. The radial thermal conductivity of carbon fibers has a significant effect on the vertical ETC. When it decreased to 0.2 W / m · ° C , the vertical ETC decreased by 6.15 % compared with the control group. The temperature variation trend of specimens were measured by a laboratory irradiation experiment. The maximum temperature difference between the control group and the experimental group at 0 mm was 5.81 °C, and the average temperature difference within 2 h was 5.14 °C. The maximum temperature difference at 50 mm was 3.84 °C and the average temperature difference within 2 h was 3.24 °C. The results showed that the transverse heat transfer channel can reduce downward heat transfer. The application of the channels will enhance transverse heat release and relieve heat accumulation of asphalt pavement. This can create a low temperature state for pavement structure and has a positive effect on maintaining the stability of the permafrost regions on the Qinghai-Tibet Plateau. [ABSTRACT FROM AUTHOR]

To better understand the role of resting cysts in the outbreak of paralytic shellfish poisoning and bloom dynamics in Jinhae-Masan Bay, Korea, this study investigated the germination features of ellipsoidal Alexandrium cysts isolated from sediments collected in winter and summer under different combinations of temperature and salinity. Morphology and phylogeny of germling cells revealed that the ellipsoidal Alexandrium cysts belong to Alexandrium catenella (Group I). The cysts could germinate across a wide range of temperature (5–25 °C) with germination success within 5 days, indicating that continuous seeding for the maintenance of vegetative cells in the water column may occur through the year without an endogenous clock to regulate germination timing. In addition, the cyst germination of A. catenella (Group I) was not controlled by seasonal salinity changes. Based on the results, this study provides a schematic scenario of the bloom development of A. catenella (Group I) in Jinhae-Masan Bay, Korea. • Alexandrium catenella (Group I) cysts in Jinhae-Masan Bay can germinate under a wide range of temperatures without an endogenous clock to regulate germination timing. • A. catenella (Group I) cysts isolated from the surface sediments in winter and summer exhibit different ranges of germination temperatures. • Cyst germination of A. catenella (Group I) in Jinhae-Masan Bay is not controlled by seasonal salinity changes. [ABSTRACT FROM AUTHOR]

A versatile porous adsorbent of sulfonated polystyrene/ferrosoferric oxide/diazoresin (SPS/Fe 3 O 4 /DR) nanocomposite microspheres with magnetic property and acidic/basic groups was prepared and applied for removal of different dyes from water. The adsorbent showed good adsorption performance due to its functional groups and strong adsorption forces. The selective removal of methylene blue (MB) from MB/methyl orange (MO) mixture can be realized using this adsorbent. The adsorption uptake capacity of the adsorbents was 223.71 mg/g and the removal efficiency was more than 90% even after five adsorption-desorption cycles. This adsorbent could be readily separated from solution within 2 min using a magnet. Furthermore, adsorption kinetics for SPS/Fe 3 O 4 /DR followed by the pseudo-second order model. Isothermal equilibrium data were fitted with Langmuir model, which indicated the adsorption process is the monolayer adsorption. This novel, low cost and high effective adsorbent possesses great potential in environmental pollution cleanup. [ABSTRACT FROM AUTHOR]

Paralytic shellfish poisoning (PSP) caused the deaths of four people in coastal area of Korea, mainly Jinhae-Masan Bay and adjacent areas, in April 1986 and in 1996. The PSP outbreaks were caused by the consumption of mussels, Mytilus edulis . The organism that caused PSP was identified, from morphological data only, as Alexandrium tamarense which is recently renamed as A. catenella , however recent studies have shown that the morphological diagnostic characteristics used to identify Alexandrium species have uncertainties and molecular tools and other criteria should be considered as well. The organism that caused past PSP outbreaks and incidents in Korea therefore need to be carefully reconsidered. The aim of this study was to re-evaluate the species really responsible for past outbreaks of PSP in Jinhae-Masan Bay, Korea. The temporal production and fluxes of the resting cysts of Alexandrium species were investigated for one year (from March 2011 to February 2012) using a sediment trap, and the morphology and phylogeny of vegetative cells germinated from the resting cysts were analysed. The production of Alexandrium species peaked in August and November, when temporal discrepancies were found in the water temperature (22.4 and 22.7 °C in August, 19.1 and 19.6 °C in November) and salinity (29.5 and 26.1 psu in August, 30.5 and 31.8 psu in November). The morphological data revealed that Alexandrium species germinated from resting cysts collected in August have a ventral pore on the 1′ plate, whereas the 1′ plate in Alexandrium species germinated from resting cysts collected in November lacks a ventral pore. Molecular phylogenetic data for the vegetative cells from the germination experiments allowed the August and November peaks to be assigned to Alexandrium catenella (Group I) and A. pacificum (Group IV), respectively. This indicates that the production of resting cysts of A. catenella can be enhanced by relatively high water temperature. This result is not consistent with those of previous studies that A. catenella responsible for PSP outbreaks was found at relatively low water temperature. In addition, large subunit ribosomal sequences data revealed that A. pacificum isolates from Korea were closely related to those from Australia, Japan and New Zealand where the PSP toxicity of shellfish and blooms occurred in the 1990s, indicating that the introduction of toxic dinoflagellates were related to ballast water from bulk-cargo shipping. Based on these results, we concluded that past PSP outbreaks in Jinhae-Masan Bay of Korea could have been caused by A. pacificum rather than by A. catenella . [ABSTRACT FROM AUTHOR]

While the initiation and development of dense bloom of Cochlodinium polykrikoides have been shown to be related to some environmental factors, little is known about the ecological role of the formation and germination of temporary cysts, nor of their significance for the rapid expansion of dense regional-scale blooms. This study examined the factors affecting the formation and germination of temporary cysts of C. polykrikoides , and provides details about the germination process. In the laboratory experiments, C. polykrikoides produced the chain-forming temporary cysts that are immobile and surrounded by a hyaline membrane. The encystment experiment indicated that darkness induces the formation of chain-forming temporary cysts, consistent with field observation of morphology and fluxes of temporary cysts. Germination occurred twice from a single four-celled temporary cysts within 24 h after exposure to light, and the germlings appeared as two-celled chain-forming vegetative cells. The germination behavior of temporary cysts of C. polykrikoides differs from that of other dinoflagellates, and this may be a survival strategy for the maintenance of population size during dense blooms. [ABSTRACT FROM AUTHOR]

The buckling problems of composite shells with initial imperfections under hydrostatic pressure are studied in this paper. A novel initial imperfection model is introduced. The analytical solutions of critical buckling pressures for composite shells both with and without the initial imperfection are derived based on the Sanders-type kinematic relations, respectively. The analytical results are compared with published experimental results and finite element (FE) results and agree well. The numerical examples are presented and the effects of initial imperfection parameters and ply angle as well as stacking sequence on the critical buckling pressures of composite shells are discussed. The results show that if the initial imperfection parameters are properly controlled, the critical buckling pressure can be dramatically improved. This could be valuable for the practical design of composite pressure hulls of an underwater vehicle. [ABSTRACT FROM AUTHOR]

This paper presents buckling solutions for composite laminated cylindrical shells in the underwater environment. Under the equilibrium governing equation of the bending stress state, two calculation formulas are proposed to predict the buckling pressure for the underwater composite cylinders with different boundary conditions. The validation of the proposed solutions in the elastic range is proved by comparison with experimental data. The influences of the geometrical imperfections generated from the process are considered by correcting the stiffness coefficients of the proposed analytical model. The results, compared with the finite element method, show that the evolution trend of the buckling pressure calculated by the developed model is close to the finite element analysis. Therefore, the proposed analytical solutions can provide a practical and efficient way for the designers to evaluate the buckling pressure of the composite shells in the design stage. • Buckling solutions for composite laminated cylindrical shells in the underwater environment are presented. • Two formulas are proposed for the buckling pressure of underwater composite cylinders with different boundary conditions. • The validation of the proposed solutions is proved by comparison with experimental data. • The influences of the geometrical imperfections generated from the process are considered. • The trend of the buckling pressure calculated by the developed model is close to the finite element analysis. [ABSTRACT FROM AUTHOR]

The buckling and strength failure of composite cylindrical shells under hydrostatic pressure are studied in this paper by experimental tests and finite element method. Experimental tests were carried out for three composite cylindrical shells with different stacking sequences. In parallel, finite element models are built to predict the buckling and strength failure pressures. The finite element results agree well with the corresponding experimental tests. A parametric study is conducted and the effects of length-radius ratio, thickness-radius ratio, ply angle and stacking sequence on the critical buckling pressure and strength failure pressure are discussed. The results show that length-radius ratio has little influence on the strength failure pressure while thickness-radius ratio, ply angle and stacking sequence have significant influences on the critical buckling pressure and strength failure pressure. The boundary line formed by the intersections between the critical buckling pressure and strength failure pressure of composite shells with same configuration is nonlinear and it is a function of length-radius ratio, thickness-radius ratio, ply angle and stacking sequence. • Buckling & strength failure of composite shells are studied by tests and FE method. • Effects of geometric & ply parameters on buckling & strength failure are analyzed. • Boundary lines between the buckling and strength failure pressures are discussed. [ABSTRACT FROM AUTHOR]

This paper presents a study of the structural response of a point absorber wave energy converter structure made of composite materials under slamming loads. Glass and carbon fibre reinforced polymers combined with a polypropylene sandwich core are adopted for the structure subjected to breaking wave and bottom slamming. Design criteria from a classification society are used in the design of the structure in composite materials. According to the results, the matrix cracking and sandwich yielding criteria are particularly important in the design of the structure. This paper also highlights the importance of initial geometrical imperfections on the buckling strength which revealed a severe reduction compared to the linear buckling analysis. • The buckling strength of a wave energy converter structure made of composite materials under slamming load is assessed. • Glass and carbon fibre reinforced polymers combined with a polypropylene sandwich core make the structure. • Design criteria from a classification society are used in the design of the structure in composite materials. • The structure was considered subjected to breaking wave and bottom slamming. [ABSTRACT FROM AUTHOR]

Abstract: Excellent soft magnetic properties of Fe82Cu1B12Si4Nb1 alloy is obtained by concentration variation of metal elements Fe and Nb, and metalloid B and Si elements. But the crystallization temperature of Fe82Cu1B12Si4Nb1 alloy is shifted to lower range in contrast to Fe73.5Cu1B7Si15.5Nb3 alloys. The value of activation energy of primary crystallization by Kissinger equation is (236±10.6) kJ and (295±5.3) kJ for Fe82Cu1B12Si4Nb1 and Fe73.5Cu1B7Si15.5Nb3 glass alloys respectively. The relationship between the time of maximum nucleation rate of the primary crystallization with different heating rate t= (Tp1-Ton)/Thr and activation energy Ep1 and Eon is yielded. The grain coarsens easily for Fe82Cu1B12Si4Nb1 in contrast to Fe73.5Cu1B7Si15.5Nb3 glass alloy. [Copyright &y& Elsevier]

• A new toxic dinoflagellate Fukuyoa koreansis was described from Korean coastal waters. • Based on the height-to-width (H/W) and depth-to- width ratios in cell size, the apical pore H/W ratio and thecal pore size, Fukuyoa koreansis could be distinguished from other Fukuoya species. • The phylogenetic position of Fukuyoa koreansis was grouped with F. cf. yasumotoi isolated from Japan and clearly divergent from other Fukuyoa species. • The required temperatures and salinities for growth distinguished Fukuyoa koreansis from Gambierdiscus species. To clarify an unspecified toxic Gambierdiscus- like species isolated from seawaters off Jeju Island, Korea, its morphology and molecular phylogeny based on the small subunit (SSU) and partial large subunit (LSU) rRNA gene sequences were examined. Cells were narrow in ventral view and broad in lateral view with a smooth surface. The round thecal pores were evenly distributed, with an average diameter of 0.41 µm. Cell depth, width and height were 51.7 ± 4.5 μm, 43.0 ± 4.2 μm and 55.0 ± 4.7 μm, respectively, and depth-to-width (D/W) and height-to-width (H/W) ratios were 1.1 ± 0.2 μm and 1.3 ± 0.02 μm, respectively. The nucleus was located in the hypotheca. Scanning electron microscope observations revealed that the cells displayed a plate formula of Po, 4′, 6′′, 6c, 6s, 5′′′ and 2′′′, and transmission electron microscope observation demonstrated that the cells contained crystal-like particles. Morphological features indicated that the unspecified Korean isolate belonged to the genus Fukuyoa , and based on the H/W and D/W ratios, the apical pore H/W ratio and thecal pore size, it could be differentiated from other Fukuyoa species. The phylogenetic analyses based on the SSU and LSU rRNA sequences revealed that the Korean isolate was nested within the genus Fukuyoa with high support, and it grouped with F. cf. yasumotoi isolated from Japan. Based on the morpho-molecular data, a new species, Fukuyoa koreansis sp. nov. is proposed. The maximum growth rate (0.254 d−1) of F. koreansis was observed at 25°C and a salinity of 25. The required levels of temperature and salinity for growth distinguished Fukuyoa koreansis from Gambierdiscus species. [ABSTRACT FROM AUTHOR]

Centrodinium punctatum is a fusiform dinoflagellate with a global marine distribution. Due to a close phylogenetic relationship of one C. punctatum strain to Alexandrium species, toxin production of this C. punctatum strain was assessed using liquid chromatography coupled to tandem mass spectrometry. The paralytic shellfish toxin (PST) profile of C. punctatum was dominated by six analogs, i.e. STX (30%), GTX-1 (20%) and neoSTX (24%), followed by GTX-2 (9%), GTX-4 (9%) and GTX-3 (8%); deoxy-STX was also putatively identified while no gymnodimines, spirolides or goniodomins were detected. This is the first record of C. punctatum producing saxitoxins. The estimated cellular toxicity was rather elevated, between 91 and 212 pg cell−1 (or 259 and 601 fmol cell−1). When considering the toxicity equivalent factors, results suggest that this species can produce high cellular toxicity compared to other STX-producing dinoflagellates. Morphological details of the sulcal area and the hypotheca of Centrodinium punctatum were re-examined by scanning electron microscopy (SEM); this revealed that in the sulcal area, the left posterior sulcal plate (Ssp) is larger and longer than the left posterior sulcal plate and extended into the hypotheca. Based on the morphological observation, a revised interpretation of the sulcus and hypotheca is proposed. [ABSTRACT FROM AUTHOR]

In the current circumscription, the Thoracosphaeraceae comprise all dinophytes exhibiting calcified coccoid cells produced during their life-history. Species hitherto assigned to Ensiculifera and Pentapharsodinium are mostly based on the monadoid stage of life-history, while the link to the coccoid stage (occasionally treated taxonomically distinct) is not always resolved. We investigated the different life-history stages and DNA sequence data of Ensiculifera mexicana and other species occurring in samples collected from all over the world. Based on concatenated ribosomal RNA gene sequences Ensiculiferaceae represented a distinct peridinalean branch, which showed a distant relationship to other calcareous dinophytes. Both molecular and morphological data (particularly of the coccoid stage) revealed the presence of three distinct clades within Ensiculiferaceae, which may include other dinophytes exhibiting a parasitic life-history stage. At a higher taxonomic level, Ensiculiferaceae showed relationships to parasites and endosymbionts (i.e., Blastodinium and Zooxanthella) as well as to dinophytes harbouring diatoms instead of chloroplasts. These unexpected phylogenetic relationships are corroborated by the presence of five cingular plates in all such taxa, which differs from the six cingular plates of most other Thoracosphaeraceae. We herein describe Ensiculiferaceae, emend the descriptions of Ensiculifera and Pentapharsodinium , erect Matsuokaea and provide several new combinations at the species level. [ABSTRACT FROM AUTHOR]

• Prorocentrum shikokuense Hada, P. donghaiense Lu and Prorocentrum obtusidens Schiller are conspecific. • Prorocentrum obtusidens is a senior to P. shikokuense and P. donghaiense. • Prorocentrum obtusidens is a separate species from P. dentatum sensu stricto , P. veloi and P. monacense. • The periflagellar area of Prorocentrum obtusidens consists of seven platelets bearing a wing-like structure and two platelets without a wing-like structure, one flagellar pore and one accessory pore. In Japanese, Chinese and Korean coastal waters, recurrent blooms of a small, elongate Prorocentrum species have been observed in recent years. In previous studies, this species has been respectively identified as P. shikokuense , P. donghaiense and P. dentatum , despite morphological similarity and identical rDNA sequences. To resolve the confusion, morphological features, including the architectural details of the periflagellar area, were examined and ribosomal DNA (rDNA) sequences were obtained from specimens collected from the East China Sea and Korean coast, and a strain established in the waters off the Canary Islands of Spain. In addition, the descriptions of the three species and allied species were reviewed. Morphological observations and a phylogeny based on the SSU, ITS region and LSU rDNA sequences revealed that the previously confused species and our studied strains are conspecific and that the morphology of strains identified as P. dentatum in the phylogenetic trees does not coincide with P. dentatum sensu stricto. The confusion can be traced back to Dodge (1975, p. 116), who considered P. veloi, P. monacense and P. obtusidens as junior heterotypic synonyms of P. dentatum. However, Dodge's P. dentatum are closer to P. obtusidens sensu stricto , rather than P. dentatum sensu stricto. P. obtusidens sensu stricto can be distinguished from P. dentatum sensu stricto by its relatively small size, parallel sides towards the anterior and a blunt anterior extension on one side. This indicates that P. obtusidens should not be considered a synonym of P. dentatum sensu stricto. In addition, a comparison of the original descriptions of P. obtusidens and allied species allowed to conclude that small, elongate Prorocentrum from Japanese, Chinese and Korean coastal waters previously identified as P. shikokuense , P. donghaiense , P. dentatum sensu Yoo and Lee (1986) and the specimens studied herein, which share identical rDNA sequences, morphologically coincide with P. obtusidens. Therefore, it is proposed that P. shikokuense and P. donghaiense should be regarded as junior synonyms of P. obtusidens. [ABSTRACT FROM AUTHOR]

The potentially harmful species Alexandrium insuetum established by the incubation of resting cysts isolated from sediment trap samples collected at Jinhae-Masan Bay, Korea was characterized by morphological and phylogenetic analysis. The effects of temperature and salinity on the growth of A. insuetum were also investigated. The resting cysts are characterized by a spherical shape, a small size (20–25 μm) and the presence of either three or four red accumulation bodies. The similarity of morphological features of the resting cysts to those of other species of the minutum group (consisting of Alexandrium minutum and A. tamutum ) indicates that the morphological features of resting cysts might improve the accuracy of the grouping of Alexandrium species. A. insuetum germinated from the resting cysts is morphologically consistent with vegetative cells reported from Korean and Japanese coastal areas, and has an partial large subunit (LSU) rDNA sequence identical to that from Japanese strains. The growth of A. insuetum was observed between salinity 20 and 35, with increasing temperature; however at 25 °C, A. insuetum could grow even at the salinity of 15. The highest growth rate (0.60 d −1 ) was observed at 25 °C and the salinity of 25, which is higher than the previously reported growth rate of A. tamarense , which is responsible for outbreaks of paralytic shellfish poisoining and blooms in Jinhae-Masan Bay. These results suggest that the proliferation of A. insuetum in Jinhae-Masan Bay is likely to be highest during the summer. [ABSTRACT FROM AUTHOR]

Composite materials have been widely used in the field of pressure shells for underwater vehicles due to their great potential. This paper presents an experimental study of composite cylindrical shells with and without the circular hole subjected to external hydrostatic pressure. The mechanical response of the composite cylindrical shells under external hydrostatic pressure is recorded by the strain acquisition system, and the buckling deformation process of the shells is also captured by the high-speed camera system. According to the experimental results, the entire compression process of the shell can be divided into three stages based on variations in strain. Based on the findings that buckling starts very early and accounts for about 35 % of the entire process, the concept of initial buckling pressure is proposed to distinguish the critical point of the shell transition from a stable state to an unstable state. It is found that the damage positions of the three shells all correspond to the troughs in the buckling waveform, and the final fiber breakage of the perforated shells with the reinforcements both occur near the reinforcement component. Finally, a comparative analysis of the strain response of the shell with the hole and the complete shell is carried out to explore their similarities and differences. The experimental results in this paper provide valuable information for the design of perforated composite pressure shells for underwater vehicles. [ABSTRACT FROM AUTHOR]

To improve the effective use of ocean energy by water jet propulsion pump, it is necessary to study the underwater suction vortex (USV), which affects the propulsion and stealth performance of water jet propulsion pump. This paper analyses the time-frequency and nonlinear dynamic characteristics of the pressure fluctuation induced by USV through high-speed photography and high-frequency pressure fluctuation tests. The nonlinear characteristics of pressure fluctuations under the conditions with and without USV are compared and analyzed based on the chaotic time series analysis theory. The results show that the chaotic characteristics of the pressure fluctuation signal are unaffected by the occurrence of USV. However, the singular attractor structure of the pressure fluctuation signals induced by USV is highly complex, and the largest Lyapunov exponent increases. Therefore, the pressure fluctuation signals induced by USV have stronger chaotic characteristics. Note that the saturation correlation dimension of the pressure fluctuation signal in the period without USV is larger than that with USV, mainly because the influence factor of the pressure fluctuation signal in the USV period is relatively single, which is primarily induced by USV. The nonlinear characteristics analysis of the pressure fluctuation signal can effectively identify the presence of USV. • The location and morphological characteristics of suction vortices are determined by high-speed photography. • The main frequency of pressure fluctuation induced by suction vortices is low frequency. • The pressure fluctuation induced by the suction vortices is chaotic. • The difference between the nonlinear characteristics of the pressure fluctuation with and without USV are revealed. [ABSTRACT FROM AUTHOR]

Sulfonated poly (ether ether ketone) (SPEEK, SP) with tetraethoxysilane (TEOS) and diethylethylammonium trifluoromethanesulfonate ([dema] [OTf]) were used to make SP/SiOx/OTf inorganic–organic composite membranes by the sol–gel method. The composite membranes were studied with respect to their structural, thermal, ionic liquid leeching (ILs), mechanical, and proton conduction properties. Fourier transform infrared spectroscopy (FT-IR) results showed that there exist intermolecular forces between the sulfonic groups, silica, and ILs in the composite membrane. Thermogravimetric (TG) results showed that the thermal stability of the SP/SiOx/OTf composite membrane is better than that of the pristine SPEEK membrane. IL leaching studies showed that the sulfonic group could help to reduce the loss of ILs. The introduction of silica in the SP/SiOx/OTf composite membrane could further reduce the loss of ILs, and also reduce the swelling degree of the composite membrane. Dynamic mechanical analysis (DMA) data showed that the introduction of silica can increase the flexibility of membranes, and improve the mechanical properties. A proton conductivity of 2.003 × 10 −2 S/cm was obtained for a 50 wt% [dema][OTf] doped SP-66/SiOx/OTF-50 composite membranes at 220 °C under anhydrous conditions. [ABSTRACT FROM AUTHOR]

• A species identified as Cochlodinium geminatum and Polykrikos geminatus reclassified. • The species was re-described as Pseudocochlodinium profundisulcus gen. et sp. nov. • Redescription based on characteristic ASC, cingulum, sulcus and molecular phylogeny. • DNA metabarcoding found a wide distribution of the species in the coastal sediments of China. • Analyzed on rRNA gene sequences suggest a possible S-N expansion or warm water preference. Harmful algal blooms (HABs) caused by an unknown dinoflagellate species have frequently occurred in the Pearl River Estuary, China Since 2006. These blooms were associated with severe water discoloration and economic losses, ranging from several km2 to 300 km2 with the maximum recorded cell density being 2.77 × 107 cells⋅L−1. This unknown dinoflagellate species was initially identified as Cochlodinium geminatum and subsequently reclassified as Polykrikos geminatus. However, after reviewing the original descriptions for Cochlodinium geminatum sensu Schütt (1895) and the genus Polykrikos , we considered this species is incongruent with their original descriptions. Further morphological examinations and particularly phylogenetic analyses based on the SSU and partial LSU rRNA genes of isolates and resting cysts from China and Japan prompted us to consider it a new species of a new genus. This new species was proposed to be Pseudocochlodinium profundisulcus gen. et sp. nov., based on its open comma-shaped apical structure complex (ASC), cingulum encircling the cell less than one and a half turns, a deep sulcus with a torsion of a half turn, either single cell or cell chain consisting of two cells with the same number of nuclei and zooids, the resting cyst bearing lobed ornaments, and the evolutionary distances from Polykrikos (and others) on the phylogenetic trees constructed using the concatenated SSU and partial LSU rRNA gene sequences. Metabarcoding investigation of surface sediment samples collected in China revealed that the species to be widely present along the entire Chinese coast with the highest abundance in the South China Sea. Further re-analysis of the Tara Oceans metabarcoding dataset targeting the SSU rRNA gene V9 domain suggested a global distribution of this new genus. Phylogenetic analyses on 46 OTUs (average length: ∼552 bases) of its LSU rRNA gene sequences (mainly D1-D2 domains) obtained from surface sediment samples revealed intraspecific genetic diversity of this species. Interestingly, based on the different distributions and the abundance of these OTUs along the coast of China, this species appeared to have expanded its distribution from the South China Sea to the northern Yellow Sea, or preferred a warm water habitat. We consider that the present work improves the taxonomy and provides important insights into the biogeography of Pseudocochlodinium profundisulcus.⋅ [ABSTRACT FROM AUTHOR]

The key to the success of matrix acidizing in carbonate reservoirs depends on the diversion efficiency of treating fluid over the total production interval, especially for treatments on vertical wells with thick formations or horizontal wells with long and heterogeneous intervals. Foamed viscoelastic-surfactant (VES) acid combined the advantage of foam and VES can distribute acid evenly in the entire production interval. However, its diversion capability and wormhole propagation behavior has not been investigated yet. Therefore, the conventional core-flooding setup was modified by adding nitrogen source and foam generator, which was used to conduct single and parallel core-flooding acidizing experiments to investigate the effect of injection rate and initial permeability on wormhole propagation, and evaluate the diversion capability under extreme permeability contrast. Furthermore, in order to characteristic the wormhole morphology, computerized tomography (CT) scanning experiments were performed on the cores after acidizing to generate a 3D view of the wormholes inside the cores. The results of single core-flooding experiments achieved the following findings: 1. The injection rate was found to be a critical parameter in maximizing the acidizing efficiency during the foamed-VES acidizing, and the optimal acid injection rate ranges from 1 mL/min to 2 mL/min under laboratory conditions. 2. The wormhole morphology changes from conical wormhole to dominant wormhole and ramified wormhole with the increase of injection rate. 3. The initial permeability of cores hardly affects the optimal injection rate and wormhole morphology, but the pore volume to breakthrough (PVbt) decreases with the increase of the core initial permeability. 4. The foamed-VES acid has a better temporary plugging capability on the cores with high permeability due to the combined effects of foam's Jamin effect and VES self-viscosified property. The parallel core-flooding experiments show that foamed-VES acid can realize the uniform distribution of acid when the permeability contrast is about 10, and overcome the limitation of conventional VES acid. However, the foamed-VES acid will work ineffectively when the permeability contrast is greater than 20. This study deepens the understanding on the foamed-VES acidizing in carbonate reservoirs and provides fundamental for field acidizing treatment design. • Foamed-VES acid was introduced to achieve uniform distribution of acid. • CT scanning was used to characteristic the wormhole morphology inside the core. • The effect of injection rate and initial permeability on wormhole propagation behavior were analyzed. • The diversion limitation of foamed-VES was investigated. [ABSTRACT FROM AUTHOR]

Metallic glasses (MGs) are promising candidates for catalysts with high efficiency for dyeing wastewater remediation, due to their metastable nature, disordered structure, and large residual stresses. However, dyeing wastewater usually contains a high concentration of inorganic ions which may have adverse effects on the degradation process, while the impacts of these ions on MGs' degradation capability have often been overlooked and still remain unknown. Thus, the roles of inorganic ions (Cl - , NO 3 - , SO 4 2 - , and H 2 PO 4 -) on the degradation of azo dye by Fe-based MG with nominal composition of Fe 81 Si 4 B 14 Cu 1 were systematically investigated. The results showed that the inorganic ions have significant influence on MG's surface morphology, degradation capability, mineralization and durability. All these aspects need to be considered prior to application of MGs for azo dyes degradation in real natural contaminated water or saline wastewater. • Inorganic ions significantly change the degradation path way of azo dyes by Fe-based MG. • Cl - , NO 3 - , SO 4 2 - and H 2 PO 4 - deteriorate the durability of Fe-based MG. • Cl - , SO 4 2 - and H 2 PO 4 - impede the Fe-MG to remove the TOC in dyeing wastewater. • This work provides reference for the application of Fe-based MG in wastewater treatment. [ABSTRACT FROM AUTHOR]

As proven from field practices in North America and Northwest China, temporary plugging and diverting acid fracturing is an indispensable technology to enhance stimulation effect and hydrocarbon production of complex carbonate reservoirs. It's well-known that the key to the success of this technology lies in creating a temporary plugging within the previously created fractures. Consequently, many scholars have conducted laboratory experiments to investigate the plugging behavior of fibers and particulates. However, the current devices nearly have certain limitations in simulating temporary plugging experiments. Aiming at this problem, this paper introduced the fracture temporary plugging evaluation system with large fracture size, and high-pressure resistance, which can meet the requirement of temporary plugging experiment. In addition, 3D printing technology was used to reproduce the roughness of acid-etched fracture surface, improving the experimental accuracy. Based on the device, a series of experiments were performed to study the effect of carrier fluids type, the injection rate, the fracture width, and the fracture morphology on plugging behavior of fibers and particulates. Experimental results show that the plugging effect of HPG fracturing fluid is better than that of slick water. Moreover, the effect of temporary plugging deteriorates with the decrease of injection rate, which can be attributed to the fact that high injection rate increases the probability of bridging and plugging. When it comes to the fracture width, only fibers have favorable plugging effect under the condition of 2 mm fracture width. However, a single type of temporary plugging agent (only fibers or particulates) cannot achieve effective plugging under the condition of 4 mm fracture width. The combination of fibers and particulates can obtain favorable plugging effect. When the fracture width increases to 6 mm, it's difficult to obtain favorable plugging effect if the diameter of particulates is less than 50% of fracture width. Hence, it is recommended to add big particulates whose diameters are at least 50% of the fracture width to improve the plugging effect. Moreover, the fracture surface morphology affects the formation time of temporary plugging, but does not affect whether temporary plugging is formed or not. This study deepens the understanding the plugging behavior of fibers and particulates within acid-etched fracture and provides fundamental for field treatment design. [ABSTRACT FROM AUTHOR]