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A concept design method of tubular column to H-beam cast modular joint with integrated inner diaphragm is introduced. Experiment research was conducted on the joints under cyclic loading. Influence of different axial compression ratio on seismic performance was studied for practical application. Test results show that proposed cast modular joint exhibits remarkable ductility, stable and efficient energy dissipation, relatively high capacity. A key issue on how to develop stable shear plastic energy dissipation capacity of panel zone is addressed by proposed cast modular joint in seismic-resistant steel framed structures. The ductility and energy dissipation capacity of cast modular joint is reduced slightly with the increase of axial compression ratio. Revised formula of panel zone strength according to ANSI/AISC 360-10 is verified to be available and conservative for cast modular joint. Furthermore, yielding sequence can be controlled by controlling the relative strength of beam to panel zone. [ABSTRACT FROM AUTHOR]

As a newly-invented and highly-efficiency strobilurin fungicide, pyraoxystrobin (SYP-3343) has been recognized as a highly poisonous toxin for a variety of aquatic organisms. Nevertheless, the developmental toxicity and potential mechanism of SYP-3343 have not been well-documented. The results showed that SYP-3343 was relatively stable and maintained within the range of 20 % in 24 h, and the LC 50 value to embryos at 72 hpf was 17.13 μg/L. The zebrafish embryotoxicity induced by 1, 2, 4, and 8 μg/L SYP-3343 is demonstrated by repressive embryo incubation, enhancive mortality rate, abnormal heart rate, malformed morphological characteristic, and impaired spontaneous coiling, indicating SYP-3343 mostly exerted its toxicity in a dose- and time-dependent manner. Besides SYP-3343 was critically involved in regulating cell cycle, mitochondrial membrane potential, and reactive oxygen species production as well as zebrafish primary cells apoptosis, which can be mitigated using antioxidant N-acetyl- L -cysteine. A significant change occurred in total protein content, the biochemical indices, and antioxidant capacities owing to SYP-3343 exposure. Additionally, SYP-3343 altered the mRNA levels of heart development-, mitochondrial function-, and apoptosis-related genes in zebrafish embryos. These results indicated that SYP-3343 induced apoptosis accompanying reactive oxygen species-initiated mitochondrial dysfunction in zebrafish embryos. [Display omitted] • SYP-3343 induces acute toxicity to zebrafish embryos. • SYP-3343 triggers pathological changes in cardiac morphology. • SYP-3343 provokes zebrafish primary cell dysfunction. • SYP-3343 triggers changes in biochemical indexes and antioxidant ability. • SYP-3343 irritates apoptosis via ROS-initiated mitochondrial dysfunction. [ABSTRACT FROM AUTHOR]

The effect of selenoprotein P (SELENOP) levels on the sensitivity of cervical cancer patients to concurrent chemoradiotherapy (CCRT) has not been reported. In this study, the effects of the variations in plasma SELENOP levels on the sensitivity of cervical cancer patients to CCRT were investigated using metabonomics. Two patient groups were evaluated, i.e., the case group: 11 patients with intermediate to advanced primary squamous cervical cancer, who developed resistance against CCRT, and the sensitivity group: 11 patients who did not develop resistance were matched in a 1:1 ratio (controls). Blood samples were collected before and after CCRT, and the plasma SELENOP levels were measured by ELISA. The different metabolites present in the plasma were analyzed by UPLC-MS-MS. SELENOP levels exhibited a significant reduction in both the resistant and sensitive groups after CCRT (F = 50.705, P < 0.001), and interaction effects between sensitivity and pre-and post-treatment on SELENOP levels were observed (F = 7.414, P = 0.013). Further, a more significant reduction in the SELENOP levels was observed in the CCRT-resistant group (mean reduction, 0.028 µg/mL; P < 0.001) than in the sensitive group (mean reduction, 0.013 µg/mL; P = 0.006). Four metabolic biomarkers, i.e., C18, C19, C20 sphingomyelin, and phosphatidylcholine 20:2/22:6, were shown to be differentially expressed between the resistant and sensitive groups pre-and post-treatment. C20 sphingomyelin levels exhibited a significant correlation with SELENOP levels (r = −0.326, P = 0.031). The levels of plasma SELENOP in the CCRT-resistant group decreased significantly, suggesting that SELENOP might affect the sensitivity by modulating lipid synthesis and metabolism. • SELENOP levels is associated with the sensitivity of cervical cancer patients to CCRT. • The levels of plasma SELENOP in the CCRT-resistant group decreased significantly. • SELENOP affects sensitivity by modulating lipid synthesis and metabolism. [ABSTRACT FROM AUTHOR]

Purpose: Toremifene (TOR) is widely used as an antineoplastic drug and has an inhibitory effect on angiogenesis in mesenteric desmoid tumors and vascular intracranial solitary fibrous tumors. However, no study has investigated the direct effect of TOR on vascular cells. This study aimed at exploring the effect of TOR on the behaviors of vascular smooth muscle cells (VSMCs). Methods: Human aortic umbilical vascular smooth muscle cells (HAVSMCs) were treated by TOR. Cell morphology, migration, adhesion, and proliferation assay were investigated. The cell cycle, apoptosis, mitochondrial membrane potential, and reactive oxygen species were assessed using flow cytometry. Caspase-3 and 9 activities were assayed using Caspase-3 and Caspase-9 Activity Assay kits, respectively. Immunofluorescence and Western blot assays were carried out to characterize protein expressions of PCNA, p53, and Rho/ROCK signaling pathway. Results: TOR damaged cytoskeleton, inhibited VSMC proliferation, migration, and adhesion, and induced abnormal cell morphology and apoptosis. The antiproliferative activity of TOR was associated with the induction of G0/G1 phase arrest, blocking the cell cycle. TOR disrupted intracellular reactive oxygen species and mitochondrial membrane potential, and enhanced p53 expression and the activities of caspase-3 and caspase-9. Thus, TOR-induced apoptosis by the mitochondrial signaling pathway. Additionally, TOR induced decreased Rho, ROCK, MLC, and pMLC proteins. Collectively, TOR may affect multiple behaviors of VSMCs by damaging cytoskeleton through the Rho/ROCK pathway. Conclusion: The adverse effect of TOR on VSMCs could be considered as an important aspect of tumor growth inhibition. [ABSTRACT FROM AUTHOR]

Vanadium-based body-centered-cubic (BCC) alloys are ideal hydrogen storage media because of their high reversible hydrogen capacities at moderate conditions. However, the rapid capacity decay in hydrogen ab-/desorption cycles prevents their practical application. In this work, V-based BCC alloys with three different V contents (V 20 Ti 38 Cr 41.4 Fe 0.6 , V 40 Ti 28.5 Cr 30.1 Fe 1.4 , V 60 Ti 19 Cr 19 Fe 2 , named as V20, V40, V60) were prepared by arc melting, and their microstructures and hydrogen ab-/desorption properties were investigated systematically. XRD results show that there is a number of C15-Laves phase presence in V20, which does not appear in V40 and V60. Meanwhile, the lattice constant of the BCC phase clearly decreases as the V content rises. These differences result in a hydrogen storage capacity of only 1.82 wt% for V20 alloy, but 2.13 wt% for V40 and 2.14 wt% for V60, and an increment in hydrogen ab-/desorption plateau pressure. The V40 and V60 alloys are chosen in de-/hydrogenation cycle test owing to higher effective storage capacities, and the results show that the V60 alloy has better cycle durability. According to the microstructural analysis of the two alloys during the cycles, the micro-strain accumulates, the cell volume expands, the particles pulverizes and the defects increase during the cycles, which eventually lead to the attenuation of the hydrogen storage capacity. The increment of the V content obviously improves the elastic properties of the alloy, which further diminishes the micro-strain accumulation, cell volume expansion, particle pulverization and defect increase, eventually resulting in a higher capacity retention and better cyclic durability. • The hydrogen storage properties of the alloys can be affected by adjusting the BCC cells through the composition design. • The relationship between cyclic durability and its affecting factors are quantified. • Smaller elastic constants, achieved by increasing the V content, helps to improve the cyclic durability of the alloy. [ABSTRACT FROM AUTHOR]

Flexible and durable electrically driven heaters (EDHs) was prepared by using silver nanowire/polydopamine modified cotton fabric (AgNW/PDA-C) as Joule heat generator and polydimethylsiloxane (PDMS) as stretchable matrix.The electric property of the EDHs was investigated, and it can show excellent electrical property and stability. The EDHs can be seen from the SEM morphology that cotton fabric was well protected by the PDMS and has good conductive network. The EDHs also exhibit excellent electrothermal performance under applied voltage. At low-voltages, it can quickly reach satisfactory steady-state temperatures that meet the needs of wearables. By improving the electrothermal model, it can be verified that there is a quadratic function relationship between electric power and steady-state temperature. Under cyclic voltage and bending tests, the EDHs can well maintain steady-state temperature and exhibit excellent dynamic and static electrothermal performance. [ABSTRACT FROM AUTHOR]

In the middle and late stages of water flooding development in oil fields, oil wells will have the characteristics of low production fluid and high water cut content, making traditional production profile combination instruments unable to meet field needs. In order to accurately obtain the flow rate of each phase of the oil-water two-phase flow under the condition of low velocity, this paper proposes a new production profile logging method that combines an ultrasonic Doppler logging tool and a combined annulus logging tool. The measurement characteristics are verified by simulation experiments. Through frequency spectrum transformation of the original ultrasonic logging data, the power spectrum curve of the oil-water two-phase flow is obtained, the oil frequency, oil amplitude and other parameters are obtained by Gaussian fitting, and the distance analysis of the obtained experimental data is performed to obtain the correlation between the variables. Finally, the PLS-SVR algorithm is used to predict the oil and water flow. The mean absolute percentage error of oil flow is 7.96%, and the mean absolute percentage error of water flow is 9.4%. The prediction results show that the proposed low-velocity oil-water two-phase split-phase flow prediction model can meet actual needs, and has higher accuracy than support vector regression (SVR) and back propagation (BP) neural network prediction models, which can provide a new theoretical support for logging interpretation of production profiles. • A new measurement method for fluid yield profile logging was proposed. • We formulated the PLS-SVR model to predict the flow of oil and water. • The accuracy of the algorithm proposed in this paper is higher than BPNN and SVR. [ABSTRACT FROM AUTHOR]

In order to clarify the gas-water two-phase flow law in horizontal wells and study the gas-water two-phase flow characteristics in horizontal wells, firstly, the gas-water two-phase in a horizontal well is numerically simulated and analyzed, and the flow pattern distribution under different well inclination angles and different phase separation flow rates is obtained. Secondly, a series of production logging instruments including CAT instrument was used to conduct experimental research on gas-water two-phase flow under different flow conditions, and the measured values of each CAT probe were extracted to reflect the local holdup under different flow patterns. Finally, SSA-BP neural network algorithm is used to identify a gas-water two-phase flow pattern in a wellbore by using experimental parameters such as center holdup, well inclination angle, spinner revolution, and CAT probe measurements. The recognition accuracy of the neural network was improved from 83.75% to 91.66%, and the operation speed was accelerated. It provides a research idea to explore the flow characteristics of gas-water two-phase flow in horizontal wells. [ABSTRACT FROM AUTHOR]

Abstract: The grain-refining behavior of TiB2 particles was investigated by the method of adding Al–4B master alloy into the melt of electrolytic low-titanium aluminum (ELTA). The results indicate that TiB2 particles will be formed when the Al–4B master alloy is added into the melt of ELTA. These TiB2 particles are produced by in situ technology, thus their surface properties are preserved and do not alter. At the bottom of the melt, the TiB2 particles are pushed to the grain boundaries because of the absence of enough titanium atoms, which indicates that TiB2 particles alone are not potent nuclei of α-Al. Though some TiB2 particles settle down at the bottom, there are still numbers of fine TiB2 particles suspended. These TiB2 particles, together with the titanium atoms left, will form much more heterogeneous nucleation sites during the solidification of the melt, resulting in the grain-refining efficiency of the ELTA with Al–4B addition being improved obviously. To investigate the grain-refining mechanism of aluminum, this method has its advantages in comparison with that of adding synthetic TiB2 particles into the melt of aluminum. [Copyright &y& Elsevier]

A new series of anionic photoacid generators (PAGs) and corresponding polymers were prepared. The thermostability of PAG bound polymers was superior to that of PAG blend polymers. PAG incorporated into the polymer main chain showed improved resolution when compared with the PAG blend polymers. This was demonstrated by extreme ultraviolet lithography (EUVL) results: the fluorine PAG bound polymer resist gave 45 nm (1 : 1), 35 nm (1 : 2), 30 nm (1 : 3) and 20 nm (1 : 4) Line/Space as well as the 50 nm (1 : 1) elbow pattern. [ABSTRACT FROM AUTHOR]

Abstract: The settlements and the grain refining action of TiB2 particles in the melt of electrolytic low-titanium aluminum (ELTA) with Al–4B addition were investigated. The results show that numerous fine TiB2 particles will be formed when Al–4B master alloy is added into the melt of ELTA at the Ti/B mass ratio of 5:1. Because of their fine sizes, though there are also TiB2 particle settlements, there will still be more TiB2 particles being suspended in the melt of the ELTA with Al–4B addition than in the melt of the pure Al with Al–5Ti–1B addition at a given Ti addition level. These fine TiB2 particles, together with the titanium atoms left in the melt, will form more heterogeneous nucleation sites during solidification of the melt, improving the grain refining efficiency and the fading-resisting ability obviously. Comparing with the method of adding Al–5Ti–1B into pure Al, the present method has advantages in resulting in the formation of fine TiB2 particles and preventing their settlements. [Copyright &y& Elsevier]

Abstract: The effect of B/Ti mass ratio on grain refining of the low-titanium aluminum produced by electrolysis was investigated by adding AlB master alloy to the melt of the low-titanium aluminum. The results show that the addition of titanium by electrolysis is an effective way of grain refining of aluminum, and addition of boron to the melt of the low-titanium aluminum can further increase the grain refining efficiency. And the best grain refining efficiency is obtained when the B/Ti mass ratio is 1:10. However, when the B/Ti mass ratio is 1:2.22 (the stoichiometric value for TiB2), the grain refining efficiency vanishes almost completely. It means that all of the solute titanium atoms in the melt of the low-titanium aluminum react with boron atoms that come from AlB master alloy to form TiB2 particles, and TiB2 particles have not grain refining ability. The grain refining efficiency seems to increase with addition of more boron to the melt after the B/Ti mass ratio exceeds 1:2.22. But the grain refining efficiency is very poor, and similar to that of pure Al refined by AlB master alloy. It further shows that TiB2 particles do not participate in grain refining, and that the excess boron atoms in the melt also cannot turn TiB2 particles into the effective nuclei for aluminum as the solute titanium atoms do. [Copyright &y& Elsevier]

The objectives of this study were (1) to determine the effect of land use on N2O emissions from Inner Mongolian semi-arid grasslands of China and (2) to evaluate the process-based DNDC model to extrapolate our field measurements from a limited number of sites to a larger temporal and spatial scale. The results suggest the following. Rainfall event was the dominant controlling factor for the seasonal variations of the N2O fluxes. The seven selected sites exhibited a similar seasonal trend in N2O emission, despite their different vegetation, land use and textures. In the typical steppe, N2O fluxes generally decrease with decreasing soil organic C (SOC) and total N content, indicating that soil C and N pools are very important in determining the spatial magnitude of the N2O flux. N2O emissions were very small during the entire growing season, averaging only 0.76 g N2O-N ha-1 day-1 for the five typical steppe sites, 0.35 g N2O-N ha-1 day-1 for the mown meadow steppe site, and 0.83 g N2O-N ha-1 day-1 from the cropped meadow steppe site. No enhanced effect due to overgrazing was observed for the N2O emission from the semi-arid grasslands. This was mainly results from the decreased SOC content due to overgrazing, which may have reduced the promoting effect of increased soil bulk density by trampling and animal excreta. Except for the mown steppe site, the model predictions of the N2O flux for the six different sites agree well with the observed values (r2 ranging from 0.35 to 0.68). It would be concluded that the DNDC model captured the key driving process for N2O emission. Nitrification was the predominant process, contributing 64–88% to the N2O emission. However, in terms of the magnitude of the N2O emission, further modifications should focus on the underestimated N2O flux during the spring and autumn periods (nitrification, freeze/thaw cycles) and the effect of topography and the mowing on N2O emission. [ABSTRACT FROM AUTHOR]

Abstract Nitric oxide emissions from a typical rice–wheat rotation system in southeastern China were continuously measured with an automatic system in 1996–1997. The seasonal pattern of the NO emissions was characterized for the non-waterlogged period of a rotation cycle. Nitric oxide emissions during the period from March through June were 3.9–6.3 folds for the fertilized plots and 1.6 folds for the unfertilized plot larger than those from November through December. Nitric oxide emissions were not detectable during the winter period from January through February. Amendment of synthetic fertilizer N significantly enhanced the NO emission by a factor of 6.5, but the enhancement was significantly mitigated by 25% through substituting ca. 16% of the synthetic fertilizer N with organic N from fermented crop residues or by 21% through deep tillage. The NO–N emission factor, defined as the amount of NO–N released per unit of synthetic fertilizer N input, was determined to be 0.025 kg NO–N kg-1 of N applied for the non-waterlogged period, which was reduced by 32% through substituting part of the synthetic N fertilizer with fermented crop residues or by 24% through deep tillage. In addition, the NO emission factor, defined as the amount of NO–N emitted from unit unfertilized area per day, was observed to be ca. 3.8 g N ha-1 d-1 . Approximately 0.55 Tg N yr-1 was likely released as NO from Chinese cultivated lands. [ABSTRACT FROM AUTHOR]

Examines the advances in atmospheric chemistry in China. Use of mechanism analysis and model simulation; Ozone variation in surface layer; Emission of greenhouse gas from agricultural fields.

Epoxy resin, as a thermosetting polymer material with good performance, has been limited in application due to its high flammability. In this investigation, porous CuO-ZnO hollow spheres (CZHS) were prepared by a hydrothermal method. By incorporation with ionic liquids loaded CuO-ZnO hollow spheres (CZHS@Ils) and ammonium polyphosphate (APP) into epoxy resin (EP) matrix, a new composite flame retardant material, named as EP/7.5APP/1.5CZHS@ILs, was developed for improvement of their thermal insulation and flame retardancy. The thermal conductivity of EP/7.5APP/1.5CZHS@ILs was measured to be 0.0197 W m −1 K −1, which is lesser than that of APP incorporated epoxy resin (EP/APP), demonstrating good thermal insulation capability. The flame retardancy were assessed using the limiting oxygen index (LOI) test, the Vertical flame testing (UL-94) test, and the cone calorimeter (CC) test. The results obtained from LOI test show that the EP/7.5APP/1.5CZHS@ILs has good flame retardancy with a LOI value of up to 28, better than that of pure EP which has a LOI value of 19.2. Moreover, a V-0 level of the EP/7.5APP/1.5CZHS@ILs was observed from the UL-94 test. The peak heat release rate (PHRR) was reduced to 257.9 kW m−2, which is 74.8 % lower than that of the pure EP. Such results are attributed to the synergy effect of CZHS@ILs and APP which offers the epoxy resin excellent flame retardancy. Taking advantages of the excellent thermal insulation, flame retardancy and better mechanical properties, the as-resulted EP/7.5APP/1.5CZHS@ILs may hold great potential for future thermal insulation and flame-retardant applications of energy saving building. [Display omitted] • CuO-ZnO composite hollow spheres were prepared by one-pot hydrothermal synthesis. • CuO-ZnO composite hollow spheres were used as the carrier of ionic liquid. • The prepared EP composite has a LOI value of 28 and its UL-94 reaches V-0 level. • Cone calorimetric test results show that PHRR drop to 257.9 kW m-2, which has excellent flame retardancy. [ABSTRACT FROM AUTHOR]