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The evaluation of the results of geometric error compensation is critical, and it can serve as the feedback of the compensation to help improve the precision of the compensation. In this paper, the closed-loop mode geometric error compensation of five-axis machine tools is presented by correcting the movements of all axes. At first, general geometric error modeling of the machine tool is proposed based on POE theory. The initial positions of linear axes and rotary axes relative to the machine tool are considered and the error twist of each axis containing position-independent errors is established. Second, the closed-loop mode is developed by analyzing the open-loop mode of geometric error compensation. The precision inverse feedback module is formed by introducing the designed tool poses. The output of the feedback is the integrated errors of the revised movements of axes relative to the ideal tool poses of nominal movements of axes. Third, the adaptive correction of movements of axes is proposed based on CSO (chicken swarm optimization). The initializing of the swarm, the Jacobian based moving of roosters, and the moving of chicks containing one mutation are developed. The fitness of the swarm is calculated using the integrated errors relative to the compensation goal in the precision inverse feedback. Finally, simulations by comparing with open-loop mode error compensation and real cutting experiments are proposed on one SmartCNC500_DRTD five-axis machine center to verify the effectiveness of the closed-loop mode geometric error compensation. [ABSTRACT FROM AUTHOR]

Lignin deposition phenomenon during the liquid-hot-water (LHW) pretreatment negatively affects substrate enzymatic digestibility (SED). To overcome this limitation of LHW, acid-free ethanol-water (EW) pretreatment with low ethanol concentration was developed. With less cellulose loss and similar hemicellulose removal, adding 10% (v/v) ethanol into water (EW10 pretreatment) resulted in a lignin removal of 5.8% higher than that of LHW pretreatment conducted at the same conditions (such as 200 °C for 40 min). Although the lignin removal did not increase significantly, differential scanning calorimetry (DSC) and X-ray photoelectron spectroscopy (XPS) characterizations indicated that LHW pretreatment-induced lignin condensation was alleviated by EW10 pretreatment, leading less lignin condensates deposited on the corresponding surface of solid substrate. Moreover, compared with lignin separated from LHW-pretreated substrate, the non-productive adsorption between EW10 pretreatment-induced lignin and cellulase was significantly weakened. As a result, the SED of EW10 pretreatment was improved to 91.7%, which was higher than LHW pretreatment by 19.5%. Due to the advantages of suppressing the deposition of lignin condensates and employing ethanol at low concentration, EW10 pretreatment shows practical significance for producing fermentable sugar from abundant non-woody biomass (bamboo) in China. [ABSTRACT FROM AUTHOR]

Mycotoxins are toxic secondary metabolites produced by different fungal species under specific environmental conditions. The common and regulated mycotoxins are such as deoxynivalenol (DON), zearalenone (ZEN), ochratoxin (OTA), aflatoxin B 1 (AFB 1), and fumonisins (FB). These mycotoxins are highly regulated in feed and food because their effects start to exert from their lowest exposures and are abundant in our common environment. However, there are other emerging mycotoxins such as apicidin, beauvericin, aurofusarin, and enniatins which are also harmful. Thus, making a total of around 500 forms of mycotoxins. The existence of mycotoxins in feed and food has a significant impact on animal and human health, which ultimately, slows down economic growth globally. According to this review, different approaches to removing multi-mycotoxin separately or simultaneously have been stated. Mostly, the review focused on the simultaneous removal of different multiple mycotoxins. This is because the current studies show a growing trend in reporting the co-existence of multiple mycotoxins in feed and food materials, however, most detoxifying approaches are for singular mycotoxins. Therefore, the physical, chemical, and biological approaches to remove multi-mycotoxin have been elucidated as well as their advantages and limitations. Furthermore, the authors give suggestions on the way forward to reduce exposure to mycotoxins and diminish their health effects in society. Lastly, the authors emphasized introducing more stringent limits for co-existing mycotoxins, especially those that have the same health effects by acting synergistically, such as AFB 1 and OTA, which both act as carcinogenic agents. [Display omitted] • Mycotoxins are highly regulated in feed and food because their effects are exerted in their very minimal doses. • There is a growing trend in reporting the co-existence of multiple mycotoxins in feed and food materials. • Different approaches of removing multi-mycotoxin separately or simultaneously are crucial to be studied. • New limits are needed for co-existing mycotoxins, especially those that have the same side effects by acting synergistically. • The biological approach of removing mycotoxins using microorganisms and/or enzymes is the efficaciously leading one. [ABSTRACT FROM AUTHOR]

Intensive reclamation and cross-sea bridge construction occurred in the Jiaozhou Bay, Qingdao, China in the last 30 years. These changes have not only reduced water volume but also altered sedimentation in the bay. Using the data collected in the 1980s, 2000s and early 2010s, bottom sediment evolution in the last 30 years in the western bay were studied. Furthermore, a numerical model was used to study the hydrodynamic environment change in the surrounding sea areas. The seabed sediment became finer in the northwestern area from the 1980s to 2003, which was mostly influenced by the reduced sediment discharge from the Dagu River. However, from 2003 to July 2014 during which the Jiaozhou Bay Bridge was built, the seabed sediment became coarser on the north side of the bridge, and became finer on the south side; in particular, two coarser sediment belts appeared across the channel bridge. Numerical simulation results indicated increased current velocity on the north side and decreased velocity on the south side of the bridge. The tidal-duration asymmetry was calculated from the tidal harmonic parameters of the model output. In the flood dominated JZB, the larger deceased tidal-duration asymmetry on the north side of the bridge could result in more coarser seabed sediment brought in from the northern bay. These could be the reasons for the coarser seabed sediment on the north side of the bridge and finer sediment on the south side after the bridge construction. Deeper water on the north side and shallower water on the south side of the bridge from 2005 to July 2014 further demonstrated the effect of hydrodynamic change caused by the bridge construction. [ABSTRACT FROM AUTHOR]

Seawalls play an important role in protecting coastal regions by resisting storm surge and waves. However, a seawall can cause seabed erosion at its foot by facilitating hydrodynamic scouring, but the effects of seabed scour on wave loads have not been sufficiently considered. This paper presents a case study of increased wave load on the Gudong seawall in the Huanghe delta, China, which has experienced serious erosion since its construction. Four commonly-used empirical formulas, which were also verified through our physical simulation experiments, were used to calculate the wave loads on the crown wall of the seawall based on observed wave conditions. The maximum allowable wave load on the seawall was also determined based on historical extreme sea conditions that caused severe damage to the seawall. Our calculations showed that, the wave load has increased at least two times since the seawall's construction due to seabed scour, and the present crown wall cannot resist large waves with a 5-year return period, much less than the 50-year return period it was designed to resist. This suggested that the reasonable design of seawalls needs to adequately consider seabed scour as well as the associated increase in of wave loads. • The seabed in front of the Gudong seawall experienced serious erosion since its construction. • The wave force on the seawall increased greatly due to seabed scouring in front of the seawall. • The seawall is now unable to withstand extreme waves with return period of 5-years. • It is necessary to consider increased wave load induced by deepening water depth in seawall design. [ABSTRACT FROM AUTHOR]

A hydrotrope-based pretreatment, benzenesulfonic acid (BA) pretreatment, was used to fractionate bamboo in this work. With optimized content (80 wt %) of BA in pretreatment liquor, about 90% of lignin and hemicellulose could be removed from bamboo under mild conditions (95 °C, 30 min or 80 °C, 60 min). The potential accessibility of BA pretreated substrate to cellulase was thus significantly improved and was also found to be much higher than those of acidic ethanol and dilute acid pretreatments. But the deposition of lignin on the surface of solid substrates, especially the BA pretreated substrate, was also observed, which showed a negative effect on the enzymatic hydrolysis efficiency. The addition of inexpensive soy protein, a bio-based lignin-shielding agent, could readily overcome this negative effect, leading the increase of enzymatic conversion of cellulose in BA pretreated substrate from 37% to 92% at a low cellulase loading of 4 FPU/g glucan. As compared to acidic ethanol and dilute acid pretreatments, the combination of BA pretreatment and soy protein could not only stably improve the efficiency of non-cellulose components removal, but also could significantly reduce the loading of cellulase. [ABSTRACT FROM AUTHOR]

Mode-division multiplexing (MDM) is an effective solution to improve the integration of photonic integrated circuits. MDM systems increase the number of channels for data transmission by introducing higher-order modes. The mode converter is a key component for MDM. In this work, we propose a novel ultra-compact mode converters in the silicon-on-insulator platform, combining beam splitters with nano strips. The nano strips are used to achieve the phase matching. The high-performance TE 1 -TE 0 , TE 2 -TE 0 , and TE 3 -TE 0 mode converters exhibit high conversion efficiency and broad transmission bandwidth, in ultra-small footprints. • An novel ultracompact mode converter combining beam splitters with nano strips has been proposed. The mode conversion efficiency from TE 1 to TE 0 reaches 81% with a small footprint of 1. 3 × 15. 1 μ m 2 . • The proposed mode converter is also able to design for higher-order mode conversion. And they also have a very good performance. [ABSTRACT FROM AUTHOR]

Mixed halide inorganic perovskite CsPbI 3-x Br x has attracted attention in the field of optoelectronics. As a desirable photoactive material, the application of CsPbI 2 Br in the field of photodetector (PD) remains to be explored. The synergistic passivation strategy based on Ag 2 S quantum dot (QD) aqueous solution improves the morphology of the CsPbI 2 Br perovskite film. At the same time, Ag 2 S/CsPbI 2 Br bulk heterojunction optimizes the energy level arrangement between perovskite and Au electrode, improves the carrier transmission and collection capacity, and thus improves the performance of PD. Ag 2 S/CsPbI 2 Br bulk heterojunction PD has an ultra-low dark current of 7.74 pA, an ultra-fast response speed of 2.95/3.07 μs, and a high switching ratio of 7.67 × 105. This work provides a method for the preparation of high-quality mixed halide perovskite materials and a strategy for the development of high-performance perovskite PDs based on bulk heterojunction. • The synergistic passivation strategy improves the morphology of CsPbI 2 Br. • Ag 2 S/CsPbI 2 Br optimizes the energy level arrangement. • Ultralow I dark of 7.74 pA and ultrafast response of 2.95/3.07 μs. [ABSTRACT FROM AUTHOR]

Abstract: Experiments on three types of soil (d 50=0.287, 0.057 and 0.034mm) with pipeline(D=4cm) either half buried or resting on the seabed under regular wave or combined with current actions were conducted in a large wave flume to investigate characteristics of soil responses. The pore pressures were measured through the soil depth and across the pipeline. When pipeline is present the measured pore pressures in sandy soil nearby the pipeline deviate considerably from that predicted by the poro-elasticity theory. The buried pipeline seems to provide a degree of resistance to soil liquefaction in the two finer soil seabeds. In the silt bed, a negative power relationship was found between maximum values of excess pore pressure p max and test intervals under the same wave conditions due to soil densification and dissipation of the pore pressure. In the case of wave combined with current, pore pressures in sandy soil show slightly decrease with time, whereas in silt soil, the current causes an increase in the excess pore pressure build-up, especially at the deeper depth. Comparing liquefaction depth with scour depth underneath the pipeline indicates that the occurrence of liquefaction is accompanied with larger scour depth under the same pipeline-bed configuration. [ABSTRACT FROM AUTHOR]

Abstract: The paper presents an experimental investigation of seabed evolution behavior around a submarine pipeline and the hydrodynamic forces on the pipeline under regular waves. Unlike the previous flume tests that have largely used beds with median sands, this study focuses on fine sediments such as sandy silt and silt. The primary objective of the study was to investigate: (i) the scour process under different wave conditions and with different sediments and (ii) the influence of the bedform evolution on the hydrodynamic forces experienced by the pipeline. In terms of scour and ripple formation, four distinct regimes of the near-field bed evolution behavior are identified which are: (I) no scour, (II) scour without ripples, (III) scour with small ripples and (IV) scour with large ripples. The influence of bedform evolution on wave forces was found to vary significantly in different regimes. In regime I, the wave forces were quite stable; in regime II and III, the wave forces underwent a gradual reduction before reaching their equilibrium values at fairly early stages of the scour process; in regime IV, the wave forces were significantly affected by the migrating ripples and can be rather unsteady throughout the testing period. [Copyright &y& Elsevier]

The Amazon River has the highest discharge in the world. Nevertheless, there is still a lack of the research on the interaction between river-diluted water and the ocean. This study used the remote sensing data (2008–2017) of the Moderate Resolution Imaging Spectroradiometer (MODIS) aboard the Aqua satellite, and data of the currents, wind fields, sea surface temperature, and water depth. The river–sea interaction off the Amazon estuary was studied by analyzing the diffusion of river-diluted water and the distribution of surface suspended particulate matter (SPM). The results revealed that the Amazon estuary has a "filter effect," whereby the distribution of the surface SPM exhibited significant spatial characteristics of being high in the nearshore area and low in the offshore area. Most of the SPM accumulated within the estuary in a fan shape, although some was distributed in the shallow water region of the continental shelf along the coasts on both sides of the estuary. The currents were found to limit the diffusion range of SPM. The flow direction and velocity of the North Brazil Current and the North Equatorial Countercurrent, which are largely driven by the magnitude of the trade wind stress, are the main forces controlling the long-distance diffusion of diluted water, thus forming unique river–sea interaction patterns in the Amazon estuary. This research provides a supplement and reference for the study of the diffusion process of SPM and river-diluted water, and on the estuarine river–sea interactions of other large rivers worldwide. [ABSTRACT FROM AUTHOR]

Based on National Oceanic and Atmospheric Administration/Advanced Very High-Resolution Radiometer (NOAA/AVHRR) remote sensing and Cross-Calibrated Multi-Platform (CCMP) wind field data from 2007 to 2019, oceanographic conditions are analysed, respectively, in the Source Area (SA) and Typical Bloom Area (TBA) of Ulva prolifera (U. prolifera) in the west of the Southern Yellow Sea (SYS) using Sea Surface Temperature (SST), Suspended Sediment Concentration (SSC) and Wind Speed over the years. The results indicate that the annual maximum SST Difference (SSTD) between U. prolifera SA and TBA is strongly consistent with the intensity of U. prolifera, and a high SST Warming Rate (WR) from May to July may constrain the U. prolifera blooms. The Taiwan Warm Current (TWC), crossing Yangtze River Estuary northward from March to April, leads to SST increasing in the SA and becomes a key trigger for the growth of U. prolifera in the early period. The amount of U. prolifera may decrease in the early period because of the lower light intensity with high SSC and turbidity in SA. The summer monsoon is one of determinants for the spread of U. prolifera, and the distribution of U. prolifera reaches its highest point with a higher mean wind speed in the TBA. [ABSTRACT FROM AUTHOR]

Waves are fundamentally important for sediment re-suspension in estuary and coastal areas, especially for silty sediments, which can be easily suspended by waves, but the differential effects of swell and wind waves are still unclear. Integrated field observations were made from November 2012 to March 2013 including waves, currents, and suspending sediments on the offshore seabed of the Huanghe Delta to explore the mechanism of sediment re-suspension in silty coastal zones. During the five months of observation, there were more than 30 winter wind events that affected the study area and induced sediment re-suspension with varying suspended sediment concentration. The observed wave composition was separated into swell and wind waves using a bandpass filter. Results show that large swell (with significant height > 1.0 m) coming from the offshore direction (NE in our study area) dominated sediment resuspension in the coastal seabed due to the fact that this wind direction had the longest average fetch. Winds from the onshore direction usually had smaller swell due to their short fetches and caused limited sediment re-suspension. The residual currents caused by NE winds also transport larger sediment. An individual NE wind event could transport sediment 8–13.6 t/m2 and 5.1–8.2 t/m2 in directions parallel and perpendicular, respectively, to the isobaths, which is much higher than the sediment transportation during an individual NW wind event, which could transport 1.5–4 t/m2 and 0.6–5 t/m2 parallel and perpendicular, respectively, to the isobaths. Our research shows that large swell and the accompanying residual currents caused by NE winds (from offshore direction) are a vital driving force for sediment resuspension and transportation in the offshore zone. • The height of swell strongly affected sediment resuspension in coastal seabed. • Large swell coming from offshore (NE in our study area) dominated sediment resuspension events in offshore zone (water depth >10 m). • During and after swell, residual currents are the major dynamics that transport sediment from coastal areas. • Abstract. [ABSTRACT FROM AUTHOR]