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An excellent compatible and cost-effective dynamic kinetic resolution (DKR) protocol has been developed by combining a novel immobilized oxovanadium racemization catalyst onto cheap diatomite (V-D) with an immobilized lipase LA resolution catalyst onto a macroporous resin (LA-MR). V-D was prepared via grinding immobilization, which may become a promising alternative for the immobilization of metals, especially precious metals due to its low cost, high efficiency, easy separation, and large reaction interface. The DKR afforded high yield (96.1%), e.e. (98.67%), and Sel (98.28%) under optimal conditions established using response surface methodology as follows: the amount of V-D 10.83 mg, reaction time 51.2 h, and temperature 48.1 °C, respectively, indicating that all the reactions in the DKR were coordinated very well. The DKR protocol was also found to have high stability up to six reuses. V-D exhibited excellent compatibility with LA-MR because the lipase immobilized onto MR did not physically contact with the vanadium species immobilized onto diatomite, thus avoiding inactivation. Considering that lipase, oxovanadium, diatomite, and MR used are relatively inexpensive, and the adsorption or grinding immobilization is simple, the LA-V-MD DKR by coupling LA-MR with V-D is a cost-effective and promising protocol for chiral secondary alcohols.

Cascading failure causes a major risk to society currently. And dynamic thermal rating (DTR) technique is a cost-effective approach to mitigate the risk by exploiting potential transmission capability. From the perspectives of service life and Braess paradox, it is important and challenging to jointly optimize the DTR placement and its operation schedule for changing system state, which is a two-stage combinatorial problem with only discrete variables, suffering from no approximation guarantee and dimension curse in traditional solving algorithms. Thus, the present work proposes a novel two-stage submodular optimization (TSSO) of DTR for risk mitigation considering placement and operation schedule. Specifically, it optimizes DTR placement with proper redundancy in first stage, and then determines the corresponding DTR operation for each system state in second stage. Under the condition of the Markov and submodular features in sub-function of risk mitigation, the submodularity of total objective function of TSSO can be proven for the first time. Based on this, a state-of-the-art efficient solving algorithm is developed that can provide a better approximation guarantee than previous studies by coordinating the separate curvature and error form. The performance of the proposed optimization model is verified by case results.

The massive integration of uncertain distributed renewable energy resources into power systems raises power imbalance concerns. Peer-to-peer (P2P) energy trading provides a promising way to balance the prosumers’ volatile energy power generation and demands locally. Particularly, to protect the privacy of prosumers, distributed P2P energy trading is broadly advocated. However, severe privacy leakage issues can emerge in the realistic fully distributed P2P energy trading paradigm. Meanwhile, in this paradigm, two-party and multi-party computations coexist, challenging the naive privacy-preserving techniques. To tackle privacy leakage issues arising from the fully distributed P2P energy trading, this paper proposes a privacy-preserving approach via hybrid secure computations. A secure multi-party computation mechanism consisting of offline and online phases is developed to ensure the security of shared data by leveraging the tailored secret sharing method. In addition, the Paillier encryption method based on the Chinese Remainder Theorem is proposed for both the secure two-party computation and the offline phase of the multi-party computation. The random encryption coefficient is designed to enhance the security of the two-party computation and simultaneously guarantee the convergence of the distributed optimization. The feasible range for the encryption coefficient is derived with a strict mathematical proof. Numerical simulations demonstrate the exactness, effectiveness, and scalability of the proposed privacy-preserving approach.

We have engineered a colorimetric sensor capable of selective and sensitive detection of amino acids. This sensor employs a supramolecular copper-dependent oxidase mimic as the probe, stemming from our prior research. The oxidase mimic is constructed through the self-assembly of commercially available guanosine monophosphate (GMP), Fmoc-lysine, and Cu2+. It catalyzes the formation of a red product with a maximum absorbance at 510 nm. The changes in color and absorbance are responsive to both the concentrations and types of amino acids present. This effect is most pronounced in the presence of histidine, with a detection limit (LOD) of 6.4 nM. Furthermore, the catalytic probe can distinguish histidine from histamine and imidazole propionate, as well as 1-methyl-histidine from 3-methyl-histidine, based on their distinct coordination capacities with copper. This underscores the high selectivity of the sensing platform. Both theoretical simulations and experimental results (including UV–vis spectra, fluorescence, and EPR) indicate that the amino acids may engage in copper center coordination, thereby impeding O2access to copper─a pivotal aspect of the oxidase catalysis. This sensing platform, characteristic of its swift response, simple fabrication, and exceptional sensitivity and selectivity, can also be applied to detect other biological analytes such as nucleotides. It holds potential for use in environmental and biochemical analyses.

As a photocatalytic anode material, hematite (α-Fe2O3) is the most promising of the three iron oxides. The two other oxides are FeO, which is seldom available, and Fe3O4, which is found naturally in magnetite. There are both theoretical and experimental methods suggested for enhancing α-Fe2O3’s reactivity. First-principles calculations led to the design of two different doping concentrations of Al-doped α-Fe2O3(0001) structures and an Al2O3/Fe2O3heterostructure in the (0001) plane. A detailed investigation of the state density and stability, band structure, local potentials, charge densities, and Bader charge analysis is presented in this paper. A reduction in energy was observed with the Al-doping of an α-Fe2O3(0001) surface slab. The increase in doping concentration favors the formation of doped systems, and Al’s presence in α-Fe2O3(0001) is an energetically favorable process. The work function increases by increasing the Al concentration on the surface compared to a pure α-Fe2O3(0001) slab. Based on Bader charge analysis and charge density difference studies, it appears that chemical bonding becomes ionic in Al-doped regions. We additionally investigate Al2O3/Fe2O3interfaces by using first-principles calculations, aiming to shed light on their geometric structure and electronic properties. Al2O3/Fe2O3interfaces are more thermodynamically favorable. The results of these studies suggest that the Al2O3/Fe2O3heterojunction is a type-III broken-gap heterojunction rather than a staggered one. Additionally, oxygen evolution reaction (OER) electrocatalysts are discussed for Al-doped systems and the interface. As a result, the most favorable rate-limiting step in high-performance electrocatalysts relies on Al atom doping concentration to modulate the electronic and structural properties of Al-doped sites, while the concentration of active sites is increased and the OER rate is improved. Providing a basic understanding of the OER process at these interfaces, the discussion will be useful for exploring and developing better catalysts and device units.

Cascading failure poses a significant risk to society. One approach to mitigate failure risk is through dynamic thermal rating (DTR) sensor, placed in transmission lines to achieve both risk mitigation and investment postponement of new lines. Sensor placement, as the basis of DTR analysis, is intrinsically a combinatorial optimization problem, while traditional solving methods cannot provide optimality guarantee and suffer easily from dimensionality curse. Besides, the risk mitigation may result in Braess paradox, a counterintuitive phenomenon that line update inversely increases failure risk. This paper proposes a submodular optimization-based DTR placement model for risk mitigation considering Braess paradox. First, a model based on Markov probability and important sampling weight techniques is utilized to efficiently quantify the failure risk before and after DTR placement. Then the risk model is applied to analytically reveal the Braess paradox condition which can invalidate the submodular formulation. For this invalidation issue, a novel submodular optimization approach is established to reformulate the risk mitigation model containing estimation error. Finally, a computationally efficient solving algorithm is designed to address this nonmonotone submodular optimization, which provides a provable approximation guarantee. The benefits brough from DTR and performance of the proposed algorithms are verified by case results.

With the widespread photovoltaic deployment to achieve the net-zero energy goal, the resulting photovoltaic waste draws attention. In China, considerable steps have not been taken for photovoltaic waste management. The lack of relevant scientific information on photovoltaic waste brings difficulties to the establishment of photovoltaic waste regulatory systems. In this study, the necessity and feasibility of photovoltaic waste recovery were investigated. In China, the photovoltaic waste stream was quantified as 48.67–60.78 million t in 2050. In photovoltaic waste, indium, selenium, cadmium, and gallium were in high risk, judging by the metal criticality analysis, which meant that their recovery was significant to alleviate the resource shortage. The full recovery method was proved to reduce the environmental burdens most. For cost and benefit analysis, the net present value/size was −1.02 $/kg according to the current industrial status. However, it can be profitable with the recovery of silver. This study provides scientific and comprehensive information for photovoltaic waste management in China and is expected to promote the sustainable development of photovoltaic industry.

Systemic lupus erythematosus (SLE) is an autoimmune condition that is characterized by the production of autoantibodies and sustained inflammatory damage. Coronary heart disease (CHD) is a common complication of SLE, significantly increases CHD-related mortality in SLE patients. Despite conventional risk factors, the mechanisms contributing to a higher CHD risk require further investigation, with the immune and inflammatory aspects of SLE playing a significant role. Endothelial cell damage and dysfunction are key factors in the progression of coronary atherosclerosis in SLE patients. This review specifically focuses on endothelial dysfunction and the role of specific microRNAs in the context of SLE and CHD. In addition, we discuss the effects and functions of oxidative stress markers, endothelial progenitor cells, and circulating endothelial cells in individuals with both SLE and CHD. We also explored the typical inflammatory markers associated with SLE and CHD, addressing their clinical significance and limitations.

A catalyst based on molybdenum oxides was prepared and used for the catalytic pyrolysis of PET (poly(ethylene terephthalate)) in a H2atmosphere to facilitate the direct conversion of PET for producing olefins (ethylene and propylene) and TPA (terephthalic acid). At a reaction temperature of 400 °C, the yields of olefins and aromatic products were the highest, reaching 10.10 and 52.16 wt %, respectively. Meanwhile, the carbon black could be entirely removed. The content of TPA in aromatic products was about 70%, and the content of benzoic acid reached 22.64%. Analyses using in situ gas chromatography (GC) and high-performance liquid chromatography (HPLC) were performed to clarify the possible reaction mechanism involved in the catalytic pyrolysis of PET. Vinyl ester was found to be an important intermediate in the formation of olefins. The molybdenum oxide catalyst promoted the cleavage of the C–O bond in the side chain of PET molecules to form TPA and monovinyl terephthalate. By catalytic hydrogenation, vinyl ester was easily attacked by H to drop off the vinyl end to form olefins, simultaneously converting the ester groups into a carboxyl group and further into a TPA. This is also the main path for the production of olefins. Meanwhile, the source of olefins also involved the hydrogenation of the coordinated quaternary cycle transition state of vinyl esters and the H transfer and cracking of monoethyl terephthalate. In addition, it was found that the presence of H2was the main reason for the reduction of carbon black products. This work is promising to promote the highly efficient utilization of waste PET and directional adjustment of pyrolysis products.

Identifying drug–protein interactions (DPIs) is crucial in drug discovery, and a number of machine learning methods have been developed to predict DPIs. Existing methods usually use unrealistic data sets with hidden bias, which will limit the accuracy of virtual screening methods. Meanwhile, most DPI prediction methods pay more attention to molecular representation but lack effective research on protein representation and high-level associations between different instances. To this end, we present the novel structure-aware multimodal deep DPI prediction model, STAMP-DPI, which was trained on a curated industry-scale benchmark data set. We built a high-quality benchmark data set named GalaxyDB for DPI prediction. This industry-scale data set along with an unbiased training procedure resulted in a more robust benchmark study. For informative protein representation, we constructed a structure-aware graph neural network method from the protein sequence by combining predicted contact maps and graph neural networks. Through further integration of structure-based representation and high-level pretrained embeddings for molecules and proteins, our model effectively captures the feature representation of the interactions between them. As a result, STAMP-DPI outperformed state-of-the-art DPI prediction methods by decreasing 7.00% mean square error (MSE) in the Davis data set and improving 8.89% area under the curve (AUC) in the GalaxyDB data set. Moreover, our model is an interpretable model with the transformer-based interaction mechanism, which can accurately reveal the binding sites between molecules and proteins.

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A water-stable thin film composed of C6H4NH2CuCl2I was fabricated using spin-coating precursor solutions that dissolved equimolar amounts of C6H4NH2I and CuCl2in N,N-dimethylformamide. Photoelectrochemical characteristics show that the C6H4NH2CuCl2I film demonstrated a stable photocurrent (∼1 μA/cm2) in an aqueous solution under white light (11.5 mW/cm2) even after 3000 s, while exhibiting a photon-to-current efficiency of 0.093% under AM1.5 (100 mW/cm2) illumination. However, these values were significantly lower than those of the CH3NH3PbX3(X = I, Cl) film in solid devices. The electron diffusion length L(e–) (373 nm) and hole diffusion length L(h+) (177 nm) in the C6H4NH2CuCl2I photoelectrode were significantly lower than those of CH3NH3PbX3, limiting the photoelectrochemical and photocatalysis performances. Moreover, L(h+) was shorter than L(e–) in the C6H4NH2CuCl2I photoelectrode, resulting in the hole-collecting efficiency [ηc(h+)] being lower than the electron-collecting efficiency [ηc(e–)]. A CuO interlayer was introduced as a hole transport layer for the C6H4NH2CuCl2I photoelectrode, which improved L(h+) and ηc(h+).

The dynamic covalent kinetic resolution protocol was efficiently used for the synthesis of the enantiopure ((R)-5-acetoxy-1,3-oxathiolan-2-yl)ethyl benzoate (PR) from substrates 2-(phenylmethoxy)acetaldehyde (A), 1,4-dithiane-2,5-diol (B), and phenyl acetate (D) by a one-pot process with 99.6% conversion, 97.3% yield, and 96.5% ee through the combination of reversible hemithioacetal transformation and enantiomer-selective lactonization catalyzed by immobilized lipase from Trichosporon laibachii. A proposed kinetic model consisting of transformation and lactonization was developed herein for the first time, fitting the experimental data very well. It was concluded that (1) the transformation in a chemical fashion may follow a power law. (2) The enzymatic lactonization may follow a sequential mechanism with product inhibition. The reaction kinetic data reveal that phenol (P1) would have strong product inhibition, while noncompetitive inhibition, product inhibition of PR, and substrate inhibition were not recognized. The model suggests that there is a common limitation of both enzyme and chemistry in the chemo-enzymatic system, and thus the amount of lipase was increased to accelerate the enzymatic lactonization and to reduce the limitation caused by the enzymatic reaction, resulting in the increase of the yield of PRsignificantly. The experimental results demonstrate that both the internal and external mass diffusion resistance could be negligible, and thus the kinetic model developed is the inherent kinetic one.

As important marine biological resources, corals produce a large amount of active organic compounds in their secondary metabolic processes, including numerous brominated, chlorinated, and iodinated compounds. These compounds, with novel structures and unique activities, guide the discovery and research of important lead compounds and novel biological mechanisms. Through a large number of literature surveys, this paper summarized a total of 145 halogenated secondary metabolites which were roughly divided into four major classes of terpenes, prostaglandins, steroids and alkaloids, and they were mainly isolated from ten coral families, Ellisellidae, Gorgoniidae, Briareidae, Plexauridae, Anthothelidae, Alcyoniidae, Clavularidae, Tubiporidae, Nephtheidae and Dendrophyllidae to the best of our knowledge. In addition, their organism species, structure composition and biological activity were also discussed in the form of a chart in this essay.

Sugarcane is recognized as the fifth largest crop globally, supplying 80 % of sugar and 40 % of bioenergy production. However, sugarcane genetic research has significantly lagged behind other crops due to its complex genetic background, high ploidy (8–13×), aneuploidy, limited flowering, and a long growth cycle (more than one year). Cross breeding began in 1887 following the discovery that sugarcane seeds could germinate. Both self- and cross-pollination and selection were conducted by sugarcane breeders, but new cultivars were often eliminated due to disease susceptibility. Within the Saccharumgenus, different species possess variable numbers of chromosomes. Wild sugarcane species intercrossed with each other, leading to development of the ‘Nobilization’ breeding strategy, which significantly improved yield, sucrose, fiber content, and disease resistance, and accelerated genetic improvement of cultivars. In recent years, scientific achievements have also been made in sugarcane genome sequencing, molecular marker development, genetic linkage map construction, localization of quantitative trait locus (QTL), and trait-associated gene identification. This review focuses on the progress in sugarcane genetic research, analyzes the technical difficulties faced, presents opportunities and challenges, and provides guidance and references for future sugarcane genetics research and cultivar breeding. Finally, it offers directions for future on sugarcane genetics.

Automatic performance tuning (Autotuning) is an increasingly critical tuning technique for the high portable performance of Exascale applications. However, constructing an autotuner from scratch remains a challenge, even for domain experts. In this work, we propose a performance tuning and knowledge management suite (PAK) to help rapidly build autotuners. In order to accommodate existing autotuning techniques, we present an autotuning protocol that is composed of an extractor, producer, optimizer, evaluator, and learner. To achieve modularity and reusability, we also define programming interfaces for each protocol component as the fundamental infrastructure, which provides a customizable mechanism to deploy knowledge mining in the performance database. PAK’s usability is demonstrated by studying two important computational kernels: stencil computation and sparse matrix-vector multiplication (SpMV). Our proposed autotuner based on PAK shows comparable performance and higher productivity than traditional autotuners by writing just a few tens of code using our autotuning protocol.

Objective: The aim of this study was to conduct a comparative proteome quantitation of Vibrio parahaemolyticus in response to cold stress, demonstrating specifically characteristic changes at proteomic level, and to analyze the possible potential risks based on cold-stressed strains. Method: Comparative proteome quantitation analysis based on Stable Isotope Labeling by Amino Acid in Cell Culture (SILAC) is combined with high resolution mass spectrometry, which minimizes errors and contributes to the higher accuracy compared with chemical or label-free approaches. Results: A total of 1182 proteins were identified, among which 601 were quantified. Catalase/peroxidase HPI, aromatic amino acid aminotransferase and 16S rRNA methyltransferase were significantly upregulated in spite of the inconsistency of some proteins expression and its corresponding mRNA expression. Glutamine synthetase, asparagine synthetase and enzymes related to pentose phosphate pathway increased as well. Some proteins associated with glycolysis, tricarboxylic acid cycle, transcription and translation were downregulated. Some proteins related to DNA synthesis were almost unchanged. Conclusion: The results demonstrated that most upregulated proteins enhance the stress resistance and self-adaptation. We assume that there may be correlation between upregulation and potential risks on seafood. Most downregulated proteins contribute to energy conservation and self-protection in order to resist various negative stresses. This study provides information on specific differences of proteome and offers some new clues to the differentiation and analysis of V. parahaemolyticus under cold stress.

In this study, binary S-scheme heterojunctions (Ag3VO4/SNW-1) with a covalent organic framework SNW-1 were synthesized using a cost-effective deposition-precipitation method. Comprehensive material characterization was conducted, including XRD, FT-IR, TGA, SEM-EDS, UV–vis, and PL analyses. The photocatalytic activity of Ag3VO4/SNW-1 was evaluated using NR dye as model pollutant. Results revealed superior performance, with a maximum NR degradation rate of 94% under optimized conditions. The binary system not only enhanced photocatalytic efficiency but also improved stability. Further investigations included free radical scavenging tests, EPR measurements, and identification of reactive active sites of NR. Reactive radicals, including ·O2-, e-, ·OH, and h+, were found to enhance the photocatalytic reaction. Economic analysis showed a 34.82% rate of return on investment (ROI) and a 36.27% break-even point (BEP), affirming the commercial potential of the binary nanocomposites. In summary, this study introduces a cost-effective, reproducible, and environmentally friendly binary nanocomposites with exceptional water pollutant removal performance, showcasing promising prospects for practical applications.

The usage of zinc-containing catalysts in glycolysis causes the residue of Zn2+in the polyethylene terephthalate (PET) degradation monomer bis-hydroxyethyl (BHET), which limits the high-value utilization of BHET. This work first used electrodeposition combined with one-time recrystallization to purify BHET. Electrodeposition was suitable for dealing the Zn2+concentrations of degradation solutions within 50–100 ppm, and decreased the content of Zn2+in BHET from 141.30 to 2.41 ppm, which reached the standard of repolymerization into PET bottles. The removal rate of Zn2+was 90 % for the degradation solutions, which decreased the concentration of Zn2+in wastewater from 100 to 8.97 ppm. Meanwhile, the Zn2+removed from the degradation solutions was deposited on cathode, which obtained metal Zn materials and realized the recycling of Zn resources from Zn(OAc)2. Therefore, electrodeposition could realize the purification of BHET, recycling of Zn(OAc)2, reducing the environmental pollution caused by the emission of Zn2+and the protection of human health, simultaneously. Electrodeposition had less water consumption, lower loss rate of BHET (from 60 % to 10 %) and shorter processing time, compared with six-times recrystallizations. This study first proposed the formation of quadridentate between BHET and Zn2+, and put forward a new three-steps electrodeposition mechanism of Zn2+: the addition of electric field destroyed the dissociation equilibrium of quadridentate and made it shift to release free Zn2+; the free Zn2+gathered to form ionic groups and they migrated to copper; Zn2+reduced on copper, of which the first step was the speed limited step.

1-Benzyl-1,10-phenanthrolin-1-ium bromide (PQBr) was synthesized as a corrosion inhibitor for N80 steel, and its corrosion inhibition at high temperatures and high HCl concentrations was investigated via the weight-loss method. The addition of PQBr other additives reduced the corrosion rate of N80 carbon steel in 20% HCl at 453 K and 3 MPa to 59.93 g·(m2·h)−1. The adsorption of PQBr onto the surface of N80 carbon steel was evaluated by SEM, EIS, and PDP. An adsorption model and kinetic parameters of PQBr had been generated and determined. DFT calculations were performed to analyze the effect of the PQBr structure on adsorption.

In determining the orbits of low Earth orbit (LEO) satellites using spaceborne GPS, the errors caused by receiver antenna phase center offset (PCO) and phase center variations (PCVs) are gradually becoming a major limiting factor for continued improvements to accuracy. Shiyan 3, a small satellite mission for space technology experimentation and climate exploration, was developed by China and launched on November 5, 2008. The dual-frequency GPS receiver payload delivers 1Hz data and provides the basis for precise orbit determination within the range of a few centimeters. The antenna PCO and PCV error characteristics and the principles influencing orbit determination are analyzed. The feasibility of PCO and PCV estimation and compensation in different directions is demonstrated through simulation and in-flight tests. The values of receiver antenna PCO and PCVs for Gravity Recovery and Climate Experiment (GRACE) and Shiyan 3 satellites are estimated from one month of data. A large and stable antenna PCO error, reaching up to 10.34cm in the z-direction, is found with the Shiyan 3 satellite. The PCVs on the Shiyan 3 satellite are estimated and reach up to 3.0cm, which is slightly larger than that of GRACE satellites. Orbit validation clearly improved with independent k-band ranging (KBR) and satellite laser ranging (SLR) measurements. For GRACE satellites, the average root mean square (RMS) of KBR residuals improved from 1.01cm to 0.88cm. For the Shiyan 3 satellite, the average RMS of SLR residuals improved from 4.95cm to 4.06cm.

As the environmental issues of organic dyes pollutants are becoming more and more severe, the need to develop emerging technologies to effectively eliminate pollutants is becoming increasingly urgent. In this work, the perovskite-type BaCeO3/Fe2O3composites were successfully synthesized by a simple ultrasonic water bath. The obtained composite was characterized by various techniques such as XRD, FTIR, SEM and UV-Vis. The photocatalytic performance of the composite was investigated by degrading rhodamine B under 25 W and 254 nm UV irradiation. Moreover, we investigated the optimum preparation conditions of BaCeO3/Fe2O3photocatalyst with a BaCeO3to Fe2O3mass ratio of 1:1 and a temperature of 50∘C for 2 h. In addition, the operating parameters of the photocatalytic reaction were systematically studied such as the initial concentration of solution, catalyst dosage and solution initial pH. The results showed that the photocatalytic decolorization rate of rhodamine B could reach 97.5% by adding 1 g/L BaCeO3/Fe2O3photocatalyst to 100 mL of 20 mg/L rhodamine B solution at pH 2 for 2 h. What’s more, the BaCeO3/Fe2O3catalyst was shown to be reusable and stable by cycling tests, and the use of active species trapping agents determined the predominance of •O2−and h+in the reaction system. Finally, the possible mechanism of enhancement of photocatalytic activity was initially discussed.

The space technology experiment and climate exploration satellite is a small satellite mission of China. A new star tracker and an ASTRO 10 star tracker were loaded on the space technology experiment and climate exploration satellite to test the new star tracker’s in-flight performance. But the aberration correction function of the test star tracker is off during its experiment mission. Thus, the aberration effect should be considered in the evaluation of the test star tracker’s performance. This study researches on the aberration correction for the star tracker’s attitude measurement and deduces the aberration correction method based on attitude quaternion data. The inter-boresight angle and the relative Euler angle results show that the aberration of the test star tracker’s attitude has been corrected successfully. The low-frequency errors of the test star tracker are also analyzed in this paper.

The visibility for low earth orbit (LEO) satellites provided by the BeiDou-2 system is analyzed and compared with the global positioning system (GPS). In addition, the spaceborne receivers’ observations are simulated by the BeiDou satellites broadcast ephemeris and LEO satellites orbits. The precise orbit determination (POD) results show that the along-track component accuracy is much better over the service area than the non-service area, while the accuracy of the other two directions keeps at the same level over different areas. However, the 3-dimensional (3D) accuracy over the two areas shows almost no difference. Only taking into consideration the observation noise and navigation satellite ephemeris errors, the 3D accuracy of the POD is about 30cm. As for the precise relative orbit determination (PROD), the 3D accuracy is much better over the eastern hemisphere than that of the western hemisphere. The baseline length accuracy is 3.4mm over the service area, and it is still better than 1cm over the non-service area. This paper demonstrates that the BeiDou regional constellation could provide global service to LEO satellites for the POD and the PROD. Finally, the benefit of geostationary earth orbit (GEO) satellites is illustrated for POD.

In this present paper, we study a class of non-linear impulsive partial differential parabolic equations. We first consider the case of one delay and two delays with forced term, then consider the case without forced term. Some sufficient conditions for the oscillation of solutions of relevant equations are obtained by using Green formula, Jesen inequalities and impulsive delay differential inequalities.

In this paper, a class of impulsive reaction-diffusion system is studied. Sufficient conditions are obtained for the global existence of solution for the impulsive system. Through considering the equi-attractivity property of the impulsive error system, the impulsive synchronisation of the reaction-diffusion system is investigated, and the sufficient conditions leading to the equi-attractivity property are obtained.

The molecular weight and distribution of lignin-cresol polymer in peroxidase-catalyzed copolymerization of lignin with cresol in the reversed micellar system can be controlled by adjusting the surfactant concentration and other factors. The maximal mean molecular weight of copolymer obtained is 1890 kDa. The surfactant sustains chain growth. The cresol and/or polycresol is incorporated into the copolymer, and the thermal property of the copolymer is improved. A correlation for copolymer mean molecular weight is developed. The synthesized copolymer drops out of solution and can be easily recovered. The materials appear to act as thermosets and may have applications as replacements of conventional phenolic resins. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 2408–2418, 2001

The molecular weight and distribution of the lignin/cresol polymer in peroxidase-catalyzed copolymerization of lignin with cresol in the reversed micellar system can be controlled by adjusting the concentration of surfactant, enzyme, cresol, lignin and the ratio of alcohol to hydrocarbon in the organic phase. The maximal mean molecular weight of copolymer obtained is up to 1890 kDa. The surfactant sustains the chain of the copolymer growth. The cresol or/and polycresol is incorporated into the copolymer, and the thermal property of the copolymer become well. The synthesized copolymer precipitates and can be easily recovered. The materials appear to act as thermosets and may have application as replacements of conventional phenolic resins.

Excessive nitrogen (N) and phosphorus (P) result in serious eutrophication of water. In this study, magnesium modified acid bentonite was prepared by the impregnation method, and nitrogen and phosphorus were simultaneously removed by the magnesium ammonium phosphate method (MAP), which solved the problem of the poor adsorption capacity of bentonite. The morphology and structure of MgO-SBt were characterized by XRD, FT-IR, SEM, EDS, XPS, BET, etc. The results show that the acidified bentonite can increase the distance between bentonite layers, the layer spacing is expanded to 1.560 nm, and the specific surface area is expanded to 95.433 m2/g. After Mg modification, the characteristic peaks of MgO appear at 2θ of 42.95°, 62.31°, and 78.72°, indicating that MgO has been successfully loaded and that MgO bonded to the surface and interior pores of the acidified bentonite, boosting adsorption performance. When the dosage of MgO-SBt is 0.25 g/L, pH = 9, and N/P ratio is 5:1, the maximum adsorption capacity of MgO-SBt for N and P can reach 193.448 mg/g and 322.581 mg/g. In addition, the mechanism of the simultaneous adsorption of nitrogen and phosphorus by MgO-SBt was deeply characterized by the kinetic model, isothermal adsorption model, and thermodynamic model. The results showed that the simultaneous adsorption of nitrogen and phosphorus by MgO-SBt was chemisorption and a spontaneous exothermic process.

Focuses on the impact of the Japanese economy on the global market. Scrutiny on economic and fiscal policy; Citation of the trade between Japan and the U.S.; Failure of the deflation scheme proposed by the Koizumi Administration.