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In response to the challenge of low accuracy in load forecasting for the steel industry， a load forecasting approach is introduced based on ICEEMDAN （improved complete ensemble empirical mode decomposition with adaptive noise）. Firstly， ICEEMDAN is employed to decompose the electricity load in the steel industry into high and low-frequency modal components. Subsequently， the genetic algorithm （GA） is used to identify the primary influencing factors of the components. The PSO-BP （particle swarm optimization-backpropagation neural network） algorithm is then applied to construct prediction models for the high and low-frequency components. Finally， the forecasted results of each component are iteratively recombined to derive the ultimate load forecasting outcomes. Case analysis results indicate that this approach exhibits minimal prediction errors and higher precision.

The deep sea fuels the world’s largest ecosystem, and a deep knowledge of its relevant evolutionary patterns can support the sustainable development of human society. It is difficult to carry out in-situ experiments under the extreme environmental conditions in the deep sea, which puts forward harsh requirements for the development of deep-sea scientific experiment equipment.This study summarizes the development status and problems regarding deep-sea scientific experiment equipment in China and abroad from the aspects of deep-sea test equipment and test sites, deep-sea in-situ exploration and experiment equipment, and experimental equipment for deep-sea environment simulation. China has independently developed a serial of equipment and technologies in the field of deep-sea scientific experiment equipment, and some of its advantageous directions have reached the international advanced level, which has promoted the progress of deep-sea scientific research. However, the country fails to build a mature industrial chain in terms of sophisticated equipment and associated key technologies, resulting in the restricted development of some equipment and prominent technological weaknesses. Therefore, we propose the following suggestions to promote deep-sea scientific research and the high-quality development of the deep-sea scientific experiment equipment: (1) strengthening top-level planning to coordinate technical research; (2) establishing incentive mechanisms to encourage innovation transformation; (3) building demonstration platforms and forming a standards system; (4) developing sensing technologies and accelerating the localization process; and (5)strengthening international cooperation to enhance innovation capacities.

With the advancement of the dual-carbon goal， the integration of a large amount of new energy sources has posed new challenges to power balance of the system. In this context， research on methods for system reserve provision considering both economy and reliability has garnered significant attention. In this regard， a multi-timescale market clearing model considering the reserve demand curve has been constructed， so that the reserve clearing results take account of both economy and reliability. Besides， diverse reserve resources across multiple time scales are considered， allowing for the balance between supply and demand of the reserve under multiple time scales through coordinated interactions among these resources. Finally， it is verified by a case study that the proposed model realizes a rational allocation of reserve， thereby improving the operational economy， safety and reliability of the system.

Power grid enterprises need to monitor the purchasing load of the agent and the changes of the market price， and evaluate the risks caused by the multiple uncertainties of the fluctuation of market transaction price， actual load fluctuation and demand response when allocating the proportion of power procurement in the multi-time scale electricity market. Based on the portfolio theory， a power procurement surrogate decision-making model of electricity purchasing agent service of decision-making model for power grid enterprises in the multi-time scale electricity market considering users’ demand response is proposed. Firstly， the transaction strategies of power grid enterprises participating in the electricity market are analyzed， and the profit and risk models of electricity purchasing agent service strategy in the multi-time scale electricity market are established. Then， the scenario analysis method is used to simulate the effect of actual load fluctuation on power procurement surrogate in this month. Based on the portfolio theory， an optimization model for the electricity purchasing agent service of power grid enterprises is constructed. Finally， the actual data of the Zhejiang spot market trial operation and the demand response exercise are used for simulation analysis. The results illustrate that the decision-making model of electricity purchasing agent service of power grid enterprises can effectively reduce the risk， and allocate the proportion of power procurement in the multi-time scale electricity market according to different risk preferences and degrees of load forecasting accuracy.

With the increasing access proportion of renewable energies and the enlarged difference between peak and valley loads， the peak regulation modes of power systems are suffering more and more severe situation. Especially in the emergency period when the supply and demand balance is tight， the requirement for the regulation flexibility in the generation side is very urgent to conduct peak shaving of the system. At present， the regulation capability in the generation side is mainly provided by a few types of power generation resources， while the flexibilities of other types of generation resources in the system， e.g.， nuclear power and external power， have not been effectively exploited and utilized. This paper aims to coordinate the flexible adjustment ability of multiple power generation resources and relieve the peak shaving pressure of the power system in the emergency period. Firstly， the framework of emergency peak shaving scheduling of the power system considering the flexibilities of multiple power generation resources is constructed. Then， an emergency period evaluation method based on day-ahead unit commitment is proposed. On this basis， an optimal dispatch model of peak shaving for the power system considering the regulation characteristics of multiple power generation resources is established. Finally， simulation results verify the effectiveness of the proposed framework and method.

To help to bring about “carbon peaking and carbon neutrality”， the traditional power system with fossil energy as its mainstay will be transformed into a new power system dominated by new energy. Zhejiang province， against such a background， has seen rapid growth in the installed capacity of photovoltaic power generation. Due to the randomness and fluctuation of photovoltaic power generation， high-proportion photovoltaic power has imposed new impact and challenges on the dispatch and operation of power system. Therefore， based on the existing research on the impact of photovoltaic power generation integration on power system， this paper summarizes and analyzes the impact of photovoltaic power generation on the balance of power generation and consumption in Zhejiang power grid， and the countermeasures as well. First， based on the characteristics of Zhejiang power grid， this paper analyzes the impact of high-proportion photovoltaic power integration on Zhejiang power grid from three aspects： typical load curve， power supply， and photovoltaic power generation support. Then， on the basis of the known impact， the relevant challenges are summarized on the short-term and medium and long-term time scales. Finally， a solution that can adapt to the effective consumption of photovoltaics and ensure the balance of the power system with the integration of high-proportion photovoltaic power in the future is proposed.

Objective: This study aimed to investigate the pollution of heavy metals in Astragalus membranaceus in the main producing areas of Gansu, and to evaluate the potential health risks of edible Astragalus membranaceus. Methods: The contents of five heavy metal elements Pb, Cd, As, Hg and Cu in Astragalus membranaceus were determined by inductively coupled plasma mass spectrometer （ICP-MS） by random sampling method, and the data were analyzed. Estimated Daily Intake （EDI）, Target Hazard Factor （THQ） and Lifetime Carcinogenicity Risk （LCR） were used for health risk assessment. Results: The average contents of Pb, Cd, As, Hg, and Cu elements in 58 batches of Astragalus membranaceus samples were 0.148, 0.024, 0.139, 0.011 and 4.569 mg/kg, respectively. According to the limited standards stipulated in the 2020 edition of the Chinese Pharmacopoeia, although the detection rate of individual elements was high, but none of them exceeds the standard. The health risk assessment model showed that EDICu＞Pb＞Hg＞Cd, and all less than 1, LCR was also less than 1×10-6. Indicated that the overall level of Astragalus membranaceus samples in this study was safe. Conclusion: The content of five heavy metals in Astragalus membranaceus produced in Gansu will not cause potential risks to the health of adults and children, and there is no potential carcinogenic risk.

The polymer with imine bonds (C═N) synthesized by condensation of aldehydes and amines was called polyimine. Graphene nanoplatelets (GNPs) were blended into polyimine by imine dynamic chemistry, and GNPs/polyimine (GNPs-P) composites were fabricated by heat-pressing. A series of thermal and mechanical properties have been tested for the matrix and GNPs-P composites. Thermogravimetric analyzer showed that the GNPs were able to improve the thermal stability of the GNPs-P composites. From the test of mechanical properties, GNPs-P composite with 0.5 wt% GNPs was superior to the matrix in bending and tensile properties. The bending and tensile strengths were 92.65 and 73.05 MPa, with an improvement of 18% and 5%. GNPs-P composites with 1 wt% GNPs showed the most significant advancement in impact properties, reaching an impact strength of 11.745 kJ·m−2 with a gain of 21.6%. Cross-sectional observations using scanning electron microscope proved that the GNPs-P composites have brittle fractures. A small number of GNPs could synergize with the matrix by bridging the cracks, creating a crack diffusion resistance and a load transfer reinforcement effect, which improved the mechanical properties of the GNPs-P composites.

Objective: This study aimed to compare the differences of volatile components in flower buds of Zingiber mioga after drying and freezing. Methods: Volatile components in flower buds of Z. mioga was determined by headspace solid phase microextraction Gas Chromatography-Mass Spectrometer（HS-SPME-GC-MS） after drying and freezing, and the relative content was calculated by peak area normalization method. Results: Drying and freezing treatment had a significant effect on the volatile components of Z. mioga flower bud. A total of 152 volatile components were identified in fresh, frozen and dried Z. mioga flower bud, containing a variety of volatile pharmacodynamic components, mainly olefins, including β-phellandrene, α-Hmulene and levorotatory-β-pinene, and their relative content was high. After drying and freezing, the amount of volatile components in Z. mioga flower bud decreased significantly. The relative content of olefins in fresh and frozen samples was higher, and the relative content of olefins and alcohols after drying was higher. After drying and freezing treatment, 25 volatile components were retained, and new volatile components appeared, giving the dried and frozen Z. mioga flower bud a unique flavor. Conclusion: Fresh, dried and frozen Z. mioga flower bud contains more physiologically active components. Compared with freezing treatment, drying treatment has a greater impact on the relative content and composition of volatile components in Z. mioga flower bud. In actual production, appropriate treatment conditions are selected according to the application purpose.

This paper introduces the origin of minimalism, discusses the advantages of minimalism style in food packaging design, and expounds the application of minimalism style in food packaging design from four aspects: Food packaging color, graphics, modeling and materials.

Objective: To reveal the effect of drying processes on the quality of Gansu purple-spoted peonycorolla tea, and to explain the drying mechanism of different drying processes. Methods: Vacuum freezing-hot air combined drying （FHCD）, variable temperature hot air drying （VHD） and vacuum freeze drying （VFD） were used to dry the flowers of peony. The active ingredient （anthocyanin content） and quality attributes （moisture content, shrinkage rate and rehydration） of the purple-spotted peony corolla tea processed by three drying processes were determined, and the energy consumption of the drying processes and sensory characteristics （appearance, tea color, taste, etc.） of corolla tea were compared with three drying processes. Results: the anthocyanin content of the purple-spotted peony corolla tea processed by the above three drying processes were 8.63%, 4.68% and 12.26%, and the rehydration of them were 491.52%, 433.28% and 531.75%, respectively. Compared with VHD, anthocyanin content of the purple-spot peony corolla tea processed by FHCD increased by 3.95%, rehydration of it increased by 58.24%, and shrinkage of it reduced by 13.82%; Compared with VFD, the efficiency of FHCD process doubled, and it's energy consumption reduced by 51.79%. The anthocyanin content of corolla tea was significantly positively correlated with shrinkage rate, rehydration and water content, and the correlation coefficients were 0.749, 0.741 and 0.738, respectively. The color of purple-spotted peony was related to the anthocyanin content. The anthocyanin content rule was: rose red corolla tea＞pink corolla tea＞white corolla tea. Conclusion: The purple-spot peony corolla tea processed by FHCD has high quality, high efficiency and energy saving. The anthocyanin content, moisture content, shrinkage rate and rehydration rate of corolla tea processed by this process were 8.63%, 9.46%, 52.85% and 492.40%, respectively. The test results provide a reference for improving the comprehensive quality and drying process of purple-spotted peony corolla tea.

With the wide application of planar sinusoidal ball movable teeth transmission in various industries，the study of its dynamic characteristics and vibration problems is also very important. Aiming at the torsional vibration model and its inherent characteristics of planar sinusoidal ball transmission mechanism，a 5-DOF torsional vibration mechanical model is established by using the lumped parameter method. Based on the undamped free vibration equation，the natural frequency and modal modes of the system are calculated. The sensitivity of the natural frequency of the system to the inertia and stiffness parameters is analyzed by the partial derivative method，and the structural parameters which have significant influence on the natural frequencies of the system are concluded. In order to avoid resonance between the system and the external excitation，the parameters with high sensitivity to the natural frequency of the system are modified to improve the operation stability of the system.

Objective To assess the brain functions and explore the neurobiological mechanism of emotional and cognitive changes in male patients with hyperuricemia. Methods Forty-one untreated male patients with hyperuricemia and 41 healthy control subjects were recraited through communities during, and all of them underwent examinations of fasting serum uric acid (SUA), neuropsychological test and resting-state functional magnetic resonance imaging (rs-fMRI). The amplitude of low-frequency fluctuation (ALFF) was analyzed to determine the seed points, and the functional connections between the abnormal seed points and the voxels of the whole brain were analyzed. Results The patients with hyperuricemia showed significantly decreased ALFF in the left inferior temporal gyrus (ITG.L) and increased ALFF in the bilateral inferior frontal gyrus (IFG.B) compared with the control subjects. The FC intensity of the bilateral cuneus (CUN.B) was enhanced when the extreme point of ITG.L was chosen as the seed point; the intensity of functional connection between the left thalamus (THA.L) and the right caudate nucleus (CAU.R) was enhanced when the extreme point of the IFG.L was the seed point. The results of SUA analysis and neuropsychological and behavioral tests showed that SUA levels were inversely correlated with the working memory reaction time (r=0.320, P=0.041), and the ALFF in the ITG.L was positively correlated with the working memory accuracy (r=0.535, P < 0.001). The ALFF in IFG.L and IFG.R was positively correlated with the accuracy of the executive function (r=0.461, P=0.002; r=0.566, P < 0.001, respectively); the strength of functional connection of the IFG.L with the THA.L and with the CAU.R was inversely correlated with sleep quality (r=-0.361, P=0.020) and depressive state (r=-0.343, P=0.028) of the patients, respectively. Conclusion Brain abnormalities at regional and network levels are present in male patients with hyperuricemia, and these findings provide new insights into the mechanisms underlying the cognitive and emotional changes in patients with hyperuricemia.

The microstructure, mechanical properties and thermal fatigue behavior at room temperature to 450℃ of ZCuAl10Fe3Mn2 alloy treated by T6, cryogenic treatment and T6 + cryogenic treatment were investigated. The microstructure and crack morphology of the alloy were observed and analyzed by XRD, OM, SEM and EDS. The results show that the mechanical properties and microstructure of ZCuAl10Fe3Mn2 alloy can be significantly improved by T6+cryogenic composite treatment. Compared with T6 treatment, the tensile strength, hardness and elongation of the alloy are increased by 7.28%, 16.96% and 23.53%, respectively; the α phase is further refined and distributed more uniformly, the density of dislocation is increased, which make the microstructure uniformity and compactness of the alloy better. The thermal fatigue properties of the alloy are also effectively improved through the improvement of comprehensive properties and the resistance to thermal stress and oxidation corrosion is enhanced. Under the same thermal cycling, the fatigue crack length is the shortest and the crack growth rate is the slowest.

In cement production, the synergistic use of municipal solid waste incineration (MSWI) fly ash provides a novel approach to solve the problem of the increasing productions of fly ash and heavy metal ions. In this study, slag-steel slag based cementitious material (referred to as metallurgical slag cementitious materials) was combined with four types of MSWI fly ash for preparing cementitious materials, all of which use sand as a binder. According to the determination of fluidity, compressive strength and Cd2+ leaching concentration of filler samples, the following are found:(1) the flow rate of filler material prepared from metallurgical slag and fly ash is 240-265 mm, which fulfills the pumping requirement of mine filling; (2) the 28-day compressive strength values are>8.88 MPa, which meets the general mine filling strength requirements (1-6.5 MPa); and (3) the Cd2+ leachate concentration is lower than the drinking water standard of 5 μg·L-1 limit. The results of X-ray diffraction, infrared spectroscopy, and thermogravimetry-differential scanning calorimetry show that the leading hydration products of gelling materials are ettringite, Friedel, and C-S-H. Furthermore, X-ray photoelectron spectroscopy results reveal that Cd2+ has a great effect on the binding energy of Al3+. Ettringite and Friedel salts are found to have a curing effect on cadmium ions.

To solve the high aluminum consumption problem in interstitial-free steel production in a steel plant, an aluminum consumption prediction model was established by mathematical statistics and BP neural networks. Compared with the multiple linear regression model, this model's result is more accurate. The influence of different smelting processes on aluminum consumption was analyzed, and the process parameters were optimized. The results show that the amount of aluminum consumption per ton of steel decreases 0.07 to 0.08 kg when the oxygen activity before RH or after decarbonization reduces by 0.005%. The effective utilization coefficient of aluminum-deoxidizing is from 70.31% to 80.35%; the aluminum consumption decreases about 0.1 kg when the temperature of steel before RH increases by 35 to 40℃. The heating utilization coefficient of aluminum thermal reaction is about 97.4%. When the blowing oxygen quantity is less than 100 m3 and greater than 100 m3, the ratio of oxygen reacting with aluminum is about 37.3% or about 74.6% respectively, and the aluminum consumption increases by 0.1 kg or 0.2 kg, respectively, with the blowing oxygen quantity increasing by 50 m3. After the process parameter optimization, the aluminum consumption decreases from 1.359 to 1.113 kg, which results in a decrease of 18.1%.

To study the reaction characteristics of iron-based oxygen carriers, a one-dimensional mathematical model was developed for the reduction process of iron-based oxygen carriers in moving beds based on the unreacted shrinking core model. In this model, the multi-stage reduction between iron-based oxygen carriers and H2/CO was considered. The average error of gas species concentration between the simulative and experimental values is 6.92%, and the average error of reduction is 11.16%. The results show that the final reduction rate of iron-based oxygen carriers is about 23%, with the main reactions including the first-stage reduction and the second-stage one, whose reduction rate is 95% and 40%, respectively. A higher reaction temperature, suitable diameter of oxygen carrier particles and suitable gas-solid ratio are helpful to improve the depth of reaction and enhance the utilization efficiency of syngas and iron-based oxygen carriers. The recommended particle diameter is 1 to 2 mm.

Based on the fact of high nitrogen pick-up, large nitrogen fluctuation and poor control in some steel works, the main aspects of nitrogen removal and nitrogen pick-up in an ultra-low-carbon Al-killed steel smelting process were summarized by analyzing the process data and sampling. The main sections for nitrogen removal are BOF decarburization period and vacuum treatment. High decarburization amount can lower the nitrogen content at the BOF endpoint. There is just a limited effect of switching between nitrogen and argon on the final nitrogen content at the BOF endpoint before the point of 70% oxygen blowing. Free oxygen is favorable for deni-trification by promoting the reaction of carbon and oxygen under the RH mode, in contrast under the VD mode. When free oxygen in liquid steel is controlled above 200×10-6, the nitrogen absorption during tapping can be controlled within 5×10-6. The nitrogen introduction of furnace charge is the important factor of nitrogen pick-up during the vacuum refining process, and it is up to 11×10-6. The minimum of nitrogen pick-up can reduce to 1×10-6 by adopting gasket sealing and argon blowing protection simultaneously.

Schistosomiasis is one of the worlds most devastating parasitic diseases, afflicting 251 million people globally. The Neotropical snail Biomphalaria glabrata is an important intermediate host of the human blood fluke Schistosoma mansoni and a predominant model for schistosomiasis research. To fully exploit this model snail for biomedical research, here we report a haplotype-like, chromosome-level assembled and annotated genome of the homozygous iM line of B. glabrata that we developed at the University of New Mexico. Using multiple sequencing platforms, including Illumina, PacBio, and Omni-C sequencing, 18 sequence contact matrices representing 18 haploid chromosomes (2n = 36) were generated (337x genome coverage), and 96.5% of the scaffold sequences were anchored to the 18 chromosomes. Protein-coding genes (n = 34,559), non-coding RNAs (n = 2,406), and repetitive elements (42.52% of the genome) were predicted for the whole genome, and detailed annotations for individual chromosomes were also provided. Using this genomic resource, we have investigated the genomic structure and organization of the Toll-like receptor (TLR) and fibrinogen-domain containing protein (FReD) genes, the two important immune-related gene families. Notably, TLR-like genes are scattered on 13 chromosomes. In contrast, almost all (39 of 40) fibrinogen-related genes (FREPs) (immunoglobulin superfamily (IgSF) + fibrinogen (FBG)) are clustered within a 5-million nucleotide region on chromosome 13, yielding insight into mechanisms involved in the diversification of FREPs. This is the first genome of schistosomiasis vector snails that has been assembled at the chromosome level, annotated, and analyzed. It serves as a valuable resource for a deeper understanding of the biology of vector snails, especially Biomphalaria snails.

Vitellogenesis is the most important process in animal reproduction, in which yolk proteins play a vital role. Among multiple yolk protein precursors, vitellogenin (Vtg) is a well-known major yolk protein (MYP) in most oviparous animals. However, the nature of MYP in the freshwater gastropod snail Biomphalaria glabrata remains elusive. In the current study, we applied bioinformatics, tissue-specific transcriptomics, ovotestis-targeted proteomics, and phylogenetics to investigate the large lipid transfer protein (LLTP) superfamily and ferritin-like family in B. glabrata. Four members of LLTP superfamily (BgVtg1, BgVtg2, BgApo1, and BgApo2), one yolk ferritin (Bg yolk ferritin), and four soma ferritins (Bg ferritin 1, 2, 3, and 4) were identified in B. glabrata genome. The proteomic analysis demonstrated that, among the putative yolk proteins, BgVtg1 was the yolk protein appearing in the highest amount in the ovotestis, followed by Bg yolk ferritin. RNAseq profile showed that the leading synthesis sites of BgVtg1 and Bg yolk ferritin are in the ovotestis (presumably follicle cells) and digestive gland, respectively. Phylogenetic analysis indicated that BgVtg1 is well clustered with Vtgs of other vertebrates and invertebrates. We conclude that, vitellogenin (BgVtg1), not yolk ferritin (Bg yolk ferritin), is the major yolk protein precursor in the schistosomiasis vector snail B. glabrata.

Circular crossbore as a common geometric construction exists widely in the engineering components. Its fatigue life is heavily decreased by the crack failure around the intersecting line. So, the typical analysis model of crossbores with mode I crack is built, and the influence of four main parameters, such as thickness–diameter ratio Y , crossbores diameter ratio Q , crack length a , and axis ratio of elliptical crack face b / a , on fracture parameter K I is presented. The results show that the distribution of K I is mainly influenced by Q and b / a , and the influence of b / a is more obvious. The value of K I is mainly influenced by Y, Q , and a , while the influence of b / a is not evident. For elliptical crack face, the K I max (maximum value of K I ) located at the short axis leads to higher crack growth rate. K I max is a crucial factor of fracture criterion, and the significance of factors on it is also analyzed here. A variance analysis of four factors is performed and their order is Y > Q > a > b / a . In addition, a calculation function of K I max is built based on 294 sets’ data and the error is analyzed by mean absolute percentage error with maximum error being less than 7.2%.