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A facile and green approach for the preparation of PEGn-NH2s from PEGn-N3s in water with DTT as the reduction reagent has been developed, avoiding the introduction of metal ions and difficulties in purification compared to the traditional synthesis process of PEGn-NH2s. A series of high-purity linear and multiarm PEGn-NH2s with different molecular weights were synthesized, demonstrating the versatility of this method. Additionally, HS-PEG45-NH2with high fidelity of thiol and amine was easily prepared through the one-step two functional group conversion of N3-PEG45-S-S-PEG45-N3, and the PEG-based NH2-PEG@AuNPs were also prepared. This technology will promote the application of PEGn-NH2s in the fields of medicine and biomaterials.

Satellite constellation networks play a pivotal role in making Beyond 5G services universally accessible to people worldwide. Inter-satellite laser communication is a crucial component of satellite communication networks. To utilize fiber amplifiers, it is imperative to couple the free-space optical beam into a single-mode fiber. However, vibrations and non-coaxial errors significantly impact coupling efficiency, thereby affecting communication quality. We have developed a parameter-free fiber coupling method based on Gaussian approximation to rectify non-coaxial errors and mitigate incident angle deviations induced by vibrations, ensuring consistently high coupling efficiency. This method is fast, stable, and parameter-free, eliminating the need for manual intervention. Furthermore, experimental results demonstrate the method’s effectiveness across the entire correction range of the correction device. In environments with strong vibrations, the communication link experiences a bit error rate of 6.734 E-2, which is reduced to zero bit errors after implementing this method in a closed loop.

We first demonstrate atmospheric turbulence compensation and optical coherent combining using a phased fiber laser array with the largest channels of sub-apertures. With multi-dimensional control of piston and tip/tilt phases on each sub-aperture, the co-phasing and adaptive fiber coupling of receiving beamlets have been achieved in all-fiber structure, and the mean received power increased by about 12 times and the scintillation index caused by turbulence decreased from 0.275 to 0.041 compared with open loop. This experiment shows the practicability and adaptive optics ability of the phased fiber laser array and suggests the great potential of its applications in urban free-space optical communications.

We demonstrated a beam conformal projection system for coherent combining of large-scale lasers over 2.1 km in turbulence 20 m above the ground, using the basic modules of a 19-element fiber phased array combined with coarse pointing by a gimbal mount. After coarse pointing and aberration corrections, the metrics (reflected light) of the combined beams from a basic module were best increased by 13.4 times, suggesting that our system promises the great effect of coherent combining under long-distance turbulence. Moreover, we tentatively realized coherent combining of two basic modules (38 lasers), which is the largest number of elements in a fiber laser coherent beam combination outdoors, to the best of our knowledge, with the metrics of combined beams increased by about 29 times.

Tomato mottle mosaic virus (ToMMV), an economically important species of the genus Tobamovirus, causes significant loss in yield and quality of tomato fruits. Here, we identified the Shandong isolate of ToMMV (ToMMV-SD) collected from symptomatic tomato fruits in Weifang, Shandong Province of China. ToMMV-SD caused symptoms such as severe mosaic, mottling, and necrosis of tomato leaves, yellow spot and necrotic lesions on tomato fruits. The obtained full genome of ToMMV-SD was 6 399 nucleotides (accession number MW373515) and had the highest identity of 99.5% with that of isolate SC13-051 from the United States of America at the genomic level. The infectious clone of ToMMV-SD was constructed and induced clear mosaic and necrotic symptoms onto Nicotiana benthamianaleaves. Several commercial tomato cultivars, harboring Tm-22resistance gene, and pepper cultivars, containing Lresistance gene, were susceptible to ToMMV-SD. Plants of Solanum melongena(eggplant) and Brassica pekinensis(napa cabbage) showed mottling symptoms, while N. tabacum cv.Zhongyan 100 displayed latent infection. ToMMV-SD did not infect plants of N. tabacum cv.Xanthi NN, Brassica rapassp. chinensis (bok choy), Raphanus sativus(radish), Vigna unguiculata cv.Yuanzhong 28-2 (cowpea), or Tm-22transgenic N. benthamiana.A quintuplex RT-PCR system differentiated ToMMV from tomato mosaic virus, tomato brown rugose fruit virus, tobacco mosaic virus, and tomato spotted wilt virus, with the threshold amount of 0.02 pg. These results highlight the threat posed by ToMMV to tomato and pepper cultivation and offer an efficient detection system for the simultaneous detection of four tobamoviruses and tomato spotted wilt virus infecting tomato plants in the field.

Rechargeable potassium-ion batteries (PIBs) have great potential in the application of electrochemical energy storage devices due to the low cost, the abundant resources and the low standard reduction potential of potassium. As electrode materials are the key factors to determine the electrochemical performance of devices, relevant research is being carried out to build high-performance PIBs. In recent years, significant progress has been made in the study of the design of inorganic electrode materials. Herein, we review the cathode materials (Prussian blue and its analogues, layered oxides and polyanionic compounds) and the anode materials (antimony-based, selenium-based and bismuth-based compounds). On the basis of previous work, the structural design principles for improving the performance of electrode materials are reasonably summarized. At the same time, the problems that need to be solved in the preparation of electrode materials and the direction of future research and improvement are pointed out.

Tomato brown rugose fruit virus (ToBRFV) is a novel tobamovirus firstly reported in 2015 and poses a severe threat to the tomato industry. So far, it has spread to 10 countries in America, Asia, and Europe. In 2019, ToBRFV was identified in Shandong Province (ToBRFV-SD), China. In this study, it was shown that ToBRFV-SD induced mild to severe mosaic and blistering on leaves, necrosis on sepals and pedicles, and deformation, yellow spots, and brown rugose necrotic lesions on fruits. ToBRFV-SD induced distinct symptoms on plants of tomato, Capsicum annumm,and Nicotiana benthamiana,and caused latent infection on plants of Solanum tuberosum, Solanum melongena,and N. tabacum cv.Zhongyan 102. All the 50 tomato cultivars tested were highly sensitive to ToBRFV-SD. The complete genomic sequence of ToBRFV-SD shared the highest nucleotide and amino acid identities with isolate IL from Israel. In the phylogenetic tree constructed with the complete genomic sequence, all the ToBRFV isolates were clustered together and formed a sister branch with tobacco mosaic virus (TMV). Furthermore, a quadruplex RT-PCR system was developed that could differentiate ToBRFV from other economically important viruses affecting tomatoes, such as TMV, tomato mosaic virus, and tomato spotted wilt virus. The findings of this study enhance our understanding of the biological and molecular characteristics of ToBRFV and provide an efficient and effective detection method for multiple infections, which is helpful in the management of ToBRFV.

Strain engineering is a highly effective tool for tuning the lattice parameter and in turn optimizing the optical, electronic, and chemical properties of numerous functional materials. In conventional methods, the strain is imposed from an additional heterogeneous substrate, bringing extra composition/phase that disturbs the mechanism investigations of the effects of lattice parameters on material properties. Here, we report a convertible-precursor-induced growing method to fulfill the elongation of the uniaxial lattice parameter of anatase TiO2with a complex structure of single-crystal-like hierarchical arrays, without changing the composition, morphology, phase, and surface states. This methodology relies on a precursor-induced oriented growth and lattice parameter modulation on the basis of the lattice mismatch from the precursor. Unlike conventional substrate-manipulating methods, the employed precursor can be converted to the final materials (i.e., anatase TiO2), which can eliminate the effects of the additional substrate. It is found that for anatase TiO2, the elongation of lattice parameter aleads to the shift-up of the conduction band bottom and can thus accelerate the reduction reactions of O2. The elongation of lattice parameter aand unique structural features make the TiO2arrays highly active for photocatalytic degradation of toluene in air, with a turnover frequency (TOF) 3.8 times and 2.1 times, respectively, that of the normal TiO2arrays and P25 powder under ultraviolet irradiation. The enhanced reduction capability is further confirmed by the much-improved efficiency to assist the photoreduction of Cr(VI) in water.

In this work, Ni–Cu bimetallic alloy nanoparticles supported on reduced graphene oxide (Ni–Cu ANPs/RGO) was successfully fabricated through a one-step hydrothermal synthesis method, where simultaneous reduction of graphene oxide, nickel salt and copper salt was performed, and relevant characterization studies were executed. This synthetic method does not require surfactants and high temperature treatment, and is recommended as a green, convenient and effective way to produce composites. The unique two-dimensional architecture of the RGO provides a large specific surface area, contributing to loading more Ni–Cu ANPs, while the uniformly distributed Ni–Cu bimetallic alloy nanoparticles enhance the electrocatalytic performance of glucose oxidation. The non-enzymatic glucose biosensor based on Ni–Cu ANPs/RGO showed a wide linear range (from 0.01 μM to 30 μM), low detection limit (0.005 μM), and excellent sensitivity (1754.72 μA mM−1cm−2). More importantly, the high reliability and the excellent selectivity in actual sample detection will broaden its practical application in electrochemical sensing.

In this Letter, we propose and demonstrate efficient adaptive optics correction of a distributed 19-element fiber laser array for both receiving and transmission for the first time, to our best knowledge. Active beam coupling from space into polarization-maintaining fibers and all-fiber active cophasing beam combining with multiple-level fiber couplers are performed. Phase distortions distributed throughout the optical path from the simulated target to the receiving port are eliminated, and nearly ideal coherent combining is achieved in the far-field. Comprehensive reception efficiency is raised up to 52 times with the whole equivalent aperture of 152 mm and the far-field power-in-the-bucket metric up to 8.27 times. The optimal array element parameters for a given whole array aperture and turbulence intensity are analyzed.

Potassium-ion storage devices are the most promising equipment for large-scale energy storage due to their low cost and abundant resource. However, the low rate and poor cycling ability of potassium-ion energy storage devices resulting from the dramatic structure changes of electrode materials during operation limit their development. Herein, a defect-rich hierarchical porous carbon nanosheets (HPCS) is successfully synthesized viaa facile Mg(OH)2template approach with low-cost coal tar pitch as carbon precursor. The ultrathin nanosheets framework with a porous structure not only accelerates the rapid infiltration of electrolyte, but also alleviates the volume expansion upon cycling. Benefiting from its unique microstructure, the optimized HPCS-900 exhibits excellent rate performance (156.2 mAh g−1at 1 A g−1) and cycling stability (130.1 mAh g−1at 1 A g−1after 1000 cycles). As a practical device application, the assembled potassium-ion capacitors (HPCS//AC) deliver a high energy density of 130 Wh kg−1and a maximum power density of 10,735 W kg−1. This work provides an exciting approach to designing advanced defect-structured carbon-based materials for high-performance potassium-ion batteries and capacitors.

Carbon-based materials are regarded as promising anode materials for potassium-ion batteries. However, owing to the limited storage sites and worse diffusion kinetics of K+, leading to inferior potassium ion storage ability. Herein, a creative strategy for molecule-microstructure modification focusing on oxygen vacancy-rich, high-internal spacial scale is proposed, which has employed to prepare porous amorphous SiOx@C composite anode for enhanced potassium-ion storage. In particular, SiOxfunctions as the inner porous skeleton of composites and contributes to storage activity. The oxygen vacancy with C-Si-(O) accelerates the electron and ion transfer and generates the active sites with enhanced concentration, and the carbon defect enlarges the interlayer spacing, resulting in rapid dynamics and greater storage capacity. As expected, the optimized SiOx@C anode delivers a superior rate performance of 265 mAh g−1at 2 A g−1. As a practical device application, the assembled potassium-ion hybrid capacitors (SiOx@C//AC) deliver a maximum energy density of 100 Wh kg−1and a satisfactory cycle stability (5000 cycles). This work sheds light on carbonaceous anode based on oxygen vacancy composite as a promising support to design efficient potassium storage systems.

In this paper, polycyclic aromatic hydrocarbons (PAHs) and soot formation in rich partially premixed flames and nonpremixed flames were studied using a blend of n-heptane and toluene. The flames were diluted with Ar, N2, and CO2to control the flame temperature. Laser-induced fluorescence, laser-induced incandescence, and two-color pyrometry were used to study the effects of flame temperature on the PAHs and soot evolution. Results show that temperature distributions are similar for different gas dilutions at low flow rates. However, the high-temperature area increases dramatically in size at high flow rates and it depends on diluents in the order Ar > N2> CO2with regard to flame temperature. With an increase in the flow rate of Ar, the higher growth rate of flame temperature and bigger region of high-temperature region can lead to a higher growth rate from small to large PAHs and higher soot volume fraction. However, for CO2dilution, the increased flow rate results in the increase of formation of large PAHs, but soot formation is reduced due to the fact that lower flame temperature suppresses the soot formation. Therefore, it can be concluded that the evolution of PAHs and soot strongly depends on flame temperature.

In addition to the 1,9- and 1,7-C60adducts, the 1,23-C60adducts are an important type of C60derivatives, where the property of the fullerene compounds is significantly affected by the addition pattern. However, much less is known on the adducts due to the less availability of the compounds. Herein, the hydroxide-promoted reactions of C60with 2-alkylmalonates are reported, which produce the 1,23-C60adducts with improved efficiency. The reactions were studied with the in situ vis–NIR spectral measurement in order to probe into the reaction mechanism. The obtained 1,23-C60adducts exhibited good thermal stability and better solubility with respect to the 1,7-isomers.

Single event effects of 1-T structure programmable read-only memory (PROM) devices fabricated with a 130-nm complementary metal oxide semiconductor-based thin/thick gate oxide anti-fuse process were investigated using heavy ions and a picosecond pulsed laser. The cross sections of a single event upset (SEU) for radiation-hardened PROMs were measured using a linear energy transfer (LET) ranging from 9.2 to 95.6 MeV cm2mg−1. The result indicated that the LET threshold for a dynamic bit upset was ~ 9 MeV cm2mg−1, which was lower than the threshold of ~ 20 MeV cm2mg−1for an address counter upset owing to the additional triple modular redundancy structure present in the latch. In addition, a slight hard error was observed in the anti-fuse structure when employing 209Bi ions with extremely high LET values (~ 91.6 MeV cm2mg−1) and large ion fluence (~ 1 × 108ions cm−2). To identify the detailed sensitive position of a SEU in PROMs, a pulsed laser with a 5-μm beam spot was used to scan the entire surface of the device. This revealed that the upset occurred in the peripheral circuits of the internal power source and I/O pairs rather than in the internal latches and buffers. This was subsequently confirmed by a 181Ta experiment. Based on the experimental data and a rectangular parallelepiped model of the sensitive volume, the space error rates for the used PROMs were calculated using the CRÈME-96 prediction tool. The results showed that this type of PROM was suitable for specific space applications, even in the geosynchronous orbit.

Pitch-based carbon materials (PBCMs) are considered as one of the most promising anodes for alkali metal-ion (Li/Na/K) batteries due to their low cost, high carbon yield, resource availability, and environmental friendliness. However, PBCMs tend to be soft carbon with low layer spacing at high temperatures, resulting in undesirable reversible capacity and poor cycling stability during repeated charging and discharging cycles, which limit their applicability to energy storage systems. To date, many studies have focused on modifying PBCMs to achieve excellent alkali metal-ion storage performance. In this review, the operating mechanisms and corresponding microstructural characteristics of PBCMs used in alkali metal-ion batteries are discussed. Additionally, the design and optimization strategies of PBCMs are summarized and discussed in detail, including morphology adjustment, heteroatom doping, composite modification, pre-oxidation, and coating strategies. Furthermore, the current research status and development prospects of PBCMs are presented, including a perspective on future research directions.

In this study, treatment of C57BL/6J (wild type, WT) mice fed a high-fat diet (HFD) with retinoic acid (RA) decreased body weight and subcutaneous and visceral fat content, reversed the apparent hepatosteatosis, and reduced hepatic intracellular triglyceride and serum alanine transaminase (ALT) and aspartate aminotransferase (AST) concentrations. Moreover, RA treatment improved glucose tolerance and insulin sensitivity in WT mice fed a HFD. However, these RA-induced effects in WT mice fed a HFD were alleviated in liver specific Sirtuin 1 (Sirt1) deficient (LKO) mice fed a HFD. Furthermore, RA also could not improve glucose tolerance and insulin sensitivity in LKO mice fed a HFD. The mechanism studies indicated that RA indeed increased the expression of hepatic Sirt1 and superoxide dismutase 2 (Sod2), and inhibited the expression of sterol regulatory element binding protein 1c (Srebp-1c) in WT mice in vivoand in vitro. RA decreased mitochondrial reactive oxygen species (ROS) production in WT primary hepatocytes and increased mitochondrial DNA (mtDNA) copy number in WT mice liver. However, these RA-mediated molecular effects were also abolished in the liver and primary hepatocytes from LKO mice. In summary, RA protected against HFD-induced hepatosteatosis by decreasing Srebp-1c expression and improving antioxidant capacity through a Sirt1-mediated mechanism.

A technique comprising coal-based direct reduction followed by magnetic separation was presented to recover iron and copper from copper slag flotation tailings. Optimal process parameters, such as re-ductant and additive ratios, reduction temperature, and reduction time, were experimentally determined and found to be as follows: a limestone ratio of 25%, a bitumite ratio of 30%, and reduction roasting at 1473 K for 90 min. Under these conditions, copper-bearing iron powders (CIP) with an iron content of 90.11% and copper content of 0.86%, indicating iron and copper recoveries of 87.25% and 83.44% respectively, were effectively obtained. Scanning electron microscopy and energy dispersive spectroscopy of the CIP revealed that some tiny copper particles were embedded in metal iron and some copper formed alloy with iron, which was difficult to achieve the separation of these two metals. Thus, the copper went into magnetic products by magnetic separation. Adding copper into the steel can produce weathering steel. Therefore, the CIP can be used as an inexpensive raw material for weathering steel.

Cloud manufacturing offers the potential to make mass manufacturing resources and capabilities more widely integrated and accessible to users through network. Most related research assumes that there exists only one management center for all manufacturing resources and capabilities in a manufacturing cloud. However, this could cause the efficiency problem (e.g. scheduling time) and harm the quality of service (e.g. response time). Actually, a large-scale manufacturing cloud should have multiple management centers to deal with massive, widely distributed manufacturing resources and capabilities and users; meanwhile, the constraint of finite manufacturing resources and capabilities and the cost of remote collaboration should be taken into consideration. Thus, this article first presents the architecture for the multi-centric management with two-level scheduling strategy combining the advantages of the centralized and decentralized decision-making. Then, after quantifying the availability and the collaborative cost of the manufacturing resources and capabilities, we propose a global optimization model for the manufacturing resources and capability allocation under the multi-centric architecture. Finally, a case study adopting our new method shows that the utilization of the manufacturing resources and capabilities would be more balanced, while the cost of the total collaboration would be reduced, compared with the typical decentralized solution. The research results can support cloud manufacturing to effectively deal with the challenge of management and allocation for increasingly large-scale and distributed manufacturing resources and capabilities.

A multiaperture receiver with a phased array is an effective approach to overcome the effect of the random optical disturbance in coherent free-space laser communications, in which one of the key technologies is how to efficiently combine the multiple laser beams received by the phased array antenna. A combining module based on coherent polarization beam combining (CPBC), which can combine multiple laser beams to one laser beam with high combining efficiency and output a linearly polarized beam, is proposed in this paper. The principle of the combining module is introduced, the coherent polarization combining efficiency of CPBC is analyzed, and the performance of the combining module is evaluated. Moreover, the feasibility and the expansibility of the proposed combining module are validated in experiments of CPBC based on active phase-locking.

Embedding direct reduction followed by magnetic separation was conducted to fully recover iron and titanium separately from beach titanomagnetite (TTM). The influences of reduction conditions, such as molar ratio of C to Fe, reduction time, and reduction temperature, were studied. The results showed that the TTM concentrate was reduced to iron and iron-titanium oxides, depending on the reduction time, and the reduction sequence at 1200 °C was suggested as follows; Fe2. 75Ti0. 25O4→Fe2TiO4→FeTiO3→FeTi2O5. The reduction temperature played a considerable role in the reduction of TTM concentrates. Increasing temperature from 1100 to 1200 °C was beneficial to recovering titanium and iron, whereas the results deteriorated as temperature increased further. The results of X-ray diffraction and scanning electron microscopy analyses showed that low temperature (≤ 100 °C) was unfavorable for the gasification of reductant, resulting in insufficient reducing atmosphere in the reduction process. The molten phase was formed at high temperatures of 1250–1300 °C, which accelerated the migration rate of metallic particles and suppressed the diffusion of reduction gas, resulting in poor reduction. The optimum conditions for reducing TTM concentrate are as follows: molar ratio of C to Fe of 1. 68, reduction time of 150 min, and reduction temperature of 1200 C. Under these conditions, direct reduction iron powder, assaying 90. 28 mass% TFe and 1. 73 mass% TiO2with iron recovery of 90. 85%, and titanium concentrate, assaying 46. 24 mass% TiO2with TiO2recovery of 91. 15%, were obtained.

Embedding direct reduction followed by magnetic separation was conducted to fully recover iron and titanium separately from beach titanomagnetite (TTM). The influences of reduction conditions, such as molar ratio of C to Fe, reduction time, and reduction temperature, were studied. The results showed that the TTM concentrate was reduced to iron and iron-titanium oxides, depending on the reduction time, and the reduction sequence at 1200 °C was suggested as follows: Fe2.75Ti0.25O4→Fe2TiO4→FeTiO3→FeTi2O5. The reduction temperature played a considerable role in the reduction of TTM concentrates. Increasing temperature from 1100 to 1200 °C was beneficial to recovering titanium and iron, whereas the results deteriorated as temperature increased further. The results of X-ray diffraction and scanning electron microscopy analyses showed that low temperature (⩽1100 °C) was unfavorable for the gasification of reductant, resulting in insufficient reducing atmosphere in the reduction process. The molten phase was formed at high temperatures of 1250–1300 °C, which accelerated the migration rate of metallic particles and suppressed the diffusion of reduction gas, resulting in poor reduction. The optimum conditions for reducing TTM concentrate are as follows: molar ratio of C to Fe of 1.68, reduction time of 150 min, and reduction temperature of 1200 °C. Under these conditions, direct reduction iron powder, assaying 90.28 mass% TFe and 1.73 mass% TiO2with iron recovery of 90.85%, and titanium concentrate, assaying 46.24 mass% TiO2with TiO2recovery of 91.15%, were obtained.

Virtual Shack-Hartmann wavefront sensing (vSHWS) has some significant advantages and is promising for aberration measurement in the field of biomedical optical imaging. The illumination sources used in vSHWS are almost broadband, but are treated as monochromatic sources (only using center wavelength) in current data processing, which may cause errors. This work proposed a data processing method to take into account the multiple wavelengths of the broadband spectrum, named multiple-wavelength centroid-weighting method. Its feasibility was demonstrated through a series of simulations. A wavefront generated with a set of statistical human ocular aberrations was used as the target wavefront to evaluate the performance of the proposed and current methods. The results showed that their performance was very close when used for the symmetrical, but the wavefront error of the proposed method was much smaller than that of the current method when used for the asymmetrical spectrum, especially for the broader spectrum. These results were also validated by using 20 sets of clinical human ocular aberrations including normal and diseased eyes. The proposed method and the obtained conclusions have important implications for the application of vSHWS.

The effect of sodium sulfate on direct reduction of beach titanomagnetite, followed by magnetic separation, to separate iron and titanium was investigated. Direct reduced iron (DRI) with a high Fe content, low TiO2content and low iron recovery was obtained after adding sodium sulfate. When the sodium sulfate dosage was increased from 0 to 10 mass %, the Fe content of the DRI increased from 90. 00 mass% to 93. 55 mass% and the TiO2content decreased from 1. 27 mass% to 0. 70 mass%. The reduction mechanism of sodium sulfate was investigated by X-ray diffraction (XRD) and scanning electron microscopy (SEM) with energy dispersive spectrometer (EDS). Results revealed that the metallic iron grains in the reduced ore with sodium sulfate were larger than those in the ore without sodium sulfate. Sodium sulfate promoted the migration of iron as well as the accumulation and growth of metallic iron grains by low-melting-point carnegieite and troilite formed in the redox system. Low-melting-point carnegieite decreased the melting point of the system and then promoted liquefaction. Troilite could decrease the surface tension and melting point of metallic iron grains.

The effect of sodium sulfate on direct reduction of beach titanomagnetite, followed by magnetic separation, to separate iron and titanium was investigated. Direct reduced iron (DRI) with a high Fe content, low TiO2content and low iron recovery was obtained after adding sodium sulfate. When the sodium sulfate dosage was increased from 0 to 10 mass%, the Fe content of the DRI increased from 90.00 mass% to 93.55 mass% and the TiO2content decreased from 1.27 mass% to 0.70 mass%. The reduction mechanism of sodium sulfate was investigated by X-ray diffraction (XRD) and scanning electron microscopy (SEM) with energy dispersive spectrometer (EDS). Results revealed that the metallic iron grains in the reduced ore with sodium sulfate were larger than those in the ore without sodium sulfate. Sodium sulfate promoted the migration of iron as well as the accumulation and growth of metallic iron grains by low-melting-point carnegieite and troilite formed in the redox system. Low-melting-point carnegieite decreased the melting point of the system and then promoted liquefaction. Troilite could decrease the surface tension and melting point of metallic iron grains.

Monte Carlo simulation results are reported on the single event upset (SEU) triggered by the direct ionization effect of low-energy proton. The SEU cross-sections on the 45 nm static random access memory (SRAM) were compared with previous research work, which not only validated the simulation approach used herein, but also exposed the existence of saturated cross-section and the multiple bit upsets (MBUs) when the incident energy was less than 1 MeV. Additionally, it was observed that the saturated cross-section and MBUs are involved with energy loss and critical charge. The amount of deposited charge and the distribution with respect to the critical charge as the supplemental evidence are discussed.

The present work is a computational simulation of single event upset (SEU) induced by heavy ions passing through the device with Geant4-tool based on Monte Carlo transport code. Key parameters affecting SEU occurrence are examined, and related geometrical construction and critical charge are quantified. The MUlti-Functional Package for SEU Analysis (MUFPSA) has been successfully programmed and applied for SEU occurrence after the completion of device geometrical construction, critical charge, and SEU cross section calculation. The proposed MUFPSA has yielded a good agreement with MRED. Specifically, the results show that higher LET incident ions lead to increased SEU vulnerability due to more diffusion and higher energy deposition. In addition, the analytical method of radial ionization profile provides a good complementary interpretation.

This paper presents a low bit rate speech coder based on predictive lattice vector quantization (PLVQ) and time-scale modification (TSM). The coding model of proposed vocoder is built on the MELP, in which bit rate reduction is achieved by taking advantage of PLVQ and TSM techniques. PLVQ is used to encode the speech line spectrum pair (LSP) parameters, which has the advantage of lower implementation complexity than multi-stage vector quantization (MSVQ), moreover, it does not require memory for codebook storage. With our speech data base, PLVQ can save up to 4 bits/frame compared to unstructured codebook MSVQ. TSM can change the speed of speech signal with its perceptual characteristics remained. Through appending TSM as previous and post process, speech coding at bit rate about 1.1 kbps could be easily achieved without modifying the vocoder structure.

Coherent beam combining (CBC) of fiber array is a promising way to generate high power and high quality laser beams. Target-in-the-loop (TIL) technique might be an effective way to ensure atmosphere propagation compensation without wavefront sensors. In this paper, we present very recent research work about CBC of collimated fiber array using TIL technique at the Key Lab on Adaptive Optics (KLAO), CAS. A novel Adaptive Fiber Optics Collimator (AFOC) composed of phase-locking module and tip/tilt control module was developed. CBC experimental setup of three-element fiber array was established. Feedback control is realized using stochastic parallel gradient descent (SPGD) algorithm. The CBC based on TIL with piston and tip/tilt correction simultaneously is demonstrated. And the beam pointing to locate or sweep position of combined spot on target was achieved through TIL technique too. The goal of our work is achieve multi-element CBC for long-distance transmission in atmosphere.

This paper describes the design of modulation, compression coding and transmission control in underwater acoustic color image transmission system. This design adapts a special system of modulation and transmission control based on a DSP (Digital Signal Processing) chip, to cope with the complex underwater acoustic channel. The hardware block diagram and software flow chart are presented.

An efficient and sensitive electrochemical sensor for simultaneous detection of heavy metal ions was developed based on furfural/reduced graphene oxide composites (FF/RGO). The preparation of FF/RGO were performed through a one-step high-pressure assisted hydrothermal treatment, which is recommended as a green, convenient, and efficient way for the reduction of graphene oxide and the production of FF/RGO composites. RGO not only serves as the skeleton for furfural loading but also improves the conductivity of the composites in the matrix. FF/RGO with large specific surface area and abundant oxygen-containing functional groups was used to provide more binding sites for the effificient adsorption of heavy-metal ions due to the interaction between hydrophilic groups (–COOH, –OH, and –CHO) and metal cations. The developed sensor showed identifiable electrochemical response toward the heavy metal ions separately and simultaneously, exhibiting superior stability, outstanding sensitivity, selectivity and excellent analytical performance. Impressively, the sensor developed in this experiment has been successfully applied to the simultaneous determination of various heavy metal ions in actual samples, which has definitely exhibited a promising prospect in practical application.