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Cyanobacterial biomass is important for biofuel and biofertilizer, however, biomass production requires expensive chemical growth nutrients. To address this issue, we explored the useof inexpensive growth nutrient media from an integrated manure-seawater system for cyanobacterial biomass production. Salt-tolerant cyanobacterial strain HSaC and salt-sensitive cyanobacterial strain LC were tested to evaluate the potential of integrated manure-seawater media for sustainable cyanobacterial biomass production. As a prerequisite for seawater experiments, strain HSaC was grown at different NaCl concentrations (0 mM, 60 mM, 120 mM, 180 mM, 240 mM and 300 mM) to identify the optimum salt concentration. The highest biomass yield and photosynthetic pigment contents were obtained at 120 mM NaCl concentration. The highest exo-polysaccharide (EPS) content was obtained at 180 mM NaCl concentration. The treatments for the manure-seawater media were cow manure, pig manure, chicken manure and BG11, each with distilled water, diluted seawater and non-diluted seawater. The highest biomass and photosynthetic pigment yield for cyanobacterial strains LC and HSaC were obtained from 0.5 dS/m and 10 dS/m diluted seawater integrated with cow manure, respectively, but pig and chicken manure performed poorly. Overall, the biomass production and photosynthetic pigment results from cow manure-seawater were relatively better than those from the reference media (BG11). Based on the current findings, it is concluded that the growth nutrients from integrated cow manure-seawater can wholly substitute for the BG11 without affecting cyanobacterial growth, thereby reducing the usage of expensive chemical growth media. Thus,The results of study help to enhance the biomass production of both salt-sensitive and salt-tolerant cyanobacteria for sustainable biofuel and biofertilizer production. Cyanobacterial biomass is important for biofuel and biofertilizer, however, biomass production requires expensive chemical growth nutrients. To address this issue, we explored the useof inexpensive growth nutrient media from an integrated manure-seawater system for cyanobacterial biomass production. Salt-tolerant cyanobacterial strain HSaC and salt-sensitive cyanobacterial strain LC were tested to evaluate the potential of integrated manure-seawater media for sustainable cyanobacterial biomass production. As a prerequisite for seawater experiments, strain HSaC was grown at different NaCl concentrations (0 mM, 60 mM, 120 mM, 180 mM, 240 mM and 300 mM) to identify the optimum salt concentration. The highest biomass yield and photosynthetic pigment contents were obtained at 120 mM NaCl concentration. The highest exo-polysaccharide (EPS) content was obtained at 180 mM NaCl concentration. The treatments for the manure-seawater media were cow manure, pig manure, chicken manure and BG11, each with distilled water, diluted seawater and non-diluted seawater. The highest biomass and photosynthetic pigment yield for cyanobacterial strains LC and HSaC were obtained from 0.5 dS/m and 10 dS/m diluted seawater integrated with cow manure, respectively, but pig and chicken manure performed poorly. Overall, the biomass production and photosynthetic pigment results from cow manure-seawater were relatively better than those from the reference media (BG11). Based on the current findings, it is concluded that the growth nutrients from integrated cow manure-seawater can wholly substitute for the BG11 without affecting cyanobacterial growth, thereby reducing the usage of expensive chemical growth media. Thus,The results of study help to enhance the biomass production of both salt-sensitive and salt-tolerant cyanobacteria for sustainable biofuel and biofertilizer production.

Based on the observation monthly climatic data collected from 2766 weather observation stations on global during the period from 1981 to 2010, and the climatic scenarios data of SSP1_2.6、SSP1_4.5 and SSP1_8.5 scenarios released by CMIP6, the mean annual biotemperature, average total annual precipitation and potential evapotranspiration ratio on spatial resolution of 0.1º× 0.1º were respectively obtained by operating a high accuracy and speed method of surfacing modeling (HASM) (Yue, 2010, Yue et al., 2016) during all the four periods from 2020 to 2050 per decade. The method for surface modelling of land cover scenarios (SMLCS) has been developed to simulate the scenarios of land cover in Eurasia （Fan et al., 2019, 2020, 2021）. Finally, the scenario dataset of land cover under scenario SSP1_2.6、SSP1_4.5 and SSP1_8.5 were simulated by the SMLCS method from 2020 to 2050. 采用1981-2010年全球2766个气象观测站的观测月气候数据，以及CMIP6发布的SSP1_2.6、SSP1_4.5和SSP1_8.5情景的气候情景数据。通过运行高精度面建模方法（HASM）(Yue, 2010, Yue et al., 2016)，分别获得2020-2050年间每10年的空间分辨率为0.1º×0.1º的平均生物温度数据、多年平均年降水和潜在蒸散比率数据。采用自主研发的土地覆被情景曲面建模（SMLCS）方法（Fan et al., 2019, 2020, 2021），实现了SSP1_2.6、SSP1_4.5和SSP1_8.5情景的2020-2050年间每10年的全球土地覆被变化情景模拟。

Direct charge radioisotope battery having the advantages of long service lifetime, simple structure, high open circuit voltage and easily miniaturized, is a promising source for the great power of Micro-Electro-Mechanical System. Although the beta sources are the main choice for direct charge nuclear battery in the present studies,but no systematic analysis and comparison on beta sources is presented. In this work, the properties of six beta sources (including 3H(Ti3H2), 14C, 35S, 45Ca, 63Ni and 147Pm) were studied by software simulation and theoretical calculation. This study includes the differences of energy conversion efficiency and the theoretical output power for direct charge nuclear battery. The calculated results showed that the energy conversion efficiency was positively correlated with the average energy of emitted radioactive particles, and the theoretical output power was negatively correlated with half-life of beta source. 147Pm was the preferred choice considering long life, the energy conversion efficiency and the theoretical output power. Direct charge radioisotope battery having the advantages of long service lifetime, simple structure, high open circuit voltage and easily miniaturized, is a promising source for the great power of Micro-Electro-Mechanical System. Although the beta sources are the main choice for direct charge nuclear battery in the present studies,but no systematic analysis and comparison on beta sources is presented. In this work, the properties of six beta sources (including 3H(Ti3H2), 14C, 35S, 45Ca, 63Ni and 147Pm) were studied by software simulation and theoretical calculation. This study includes the differences of energy conversion efficiency and the theoretical output power for direct charge nuclear battery. The calculated results showed that the energy conversion efficiency was positively correlated with the average energy of emitted radioactive particles, and the theoretical output power was negatively correlated with half-life of beta source. 147Pm was the preferred choice considering long life, the energy conversion efficiency and the theoretical output power.

Spatio-temporal variations in extreme drought in China during 1961–2015 Spatio-temporal variations in extreme drought in China during 1961–2015

Wind turbine roll decay curves Wind turbine roll decay curves

This data set is the experimental data set of maize agroecosystem adaptation to climate change from 2018 to 2021 in Gucheng Station. It mainly contains the interannual and annual variation data of growth period, biomass, leaf area index, photosynthetic physiology, spectral characteristics, soil moisture, grain filling rate and yield of the same variety of maize at different sowing dates. This dataset has great significance for the revision of agrometeorological business service index, the improvement and regional application of agrometeorological simulation model, and the development of agrometeorological applicable technology for the study of maize ecosystem adaptation to climate change. This data set is the experimental data set of maize agroecosystem adaptation to climate change from 2018 to 2021 in Gucheng Station. It mainly contains the interannual and annual variation data of growth period, biomass, leaf area index, photosynthetic physiology, spectral characteristics, soil moisture, grain filling rate and yield of the same variety of maize at different sowing dates. This dataset has great significance for the revision of agrometeorological business service index, the improvement and regional application of agrometeorological simulation model, and the development of agrometeorological applicable technology for the study of maize ecosystem adaptation to climate change.

Studies of historical climate and environment changes in the eastern monsoonal region of China have made great progress in recent years. However, progressively studies indicate that the processes of climate and environment changes during the last 2000 years differed greatly in different regions. This is especially the case among studies based only on single-site records, possibly because of different materials, proxy indicators, dating accuracy, etc. Therefore, it is necessary to conduct comprehensive and integrated analyses of regional climate and environment changes at larger spatial scales. Here, multiple climate proxy records selected from 16 sites in southeastern China (i.e., approximately east of 105° E and south of 30° N) were used to synthesize and reconstruct the temperature and precipitation changes over the past 2000 years, and the possible forcing mechanisms behind these changes were explored. The results indicate that the integrated temperature sequence in the study region is quite comparable to the reconstructions for the entirety of China, eastern China, and the Northern Hemisphere. Several typical characteristic climate periods on centennial timescales, such as the Dark Age Cold Period, the Medieval Warm Period, the Little Ice Age, and the modern warm period of the 20th century, were well revealed in the present reconstruction. The integrated precipitation sequence shows that the dry and wet phases in southeastern China have changed significantly during the past 2000 years. Specifically, precipitation was relatively higher during the Medieval Warm Period, but it was relatively lower during the Little Ice Age (i.e., less precipitation occurred in the former part of the Little Ice Age and more precipitation occurred during the latter part). In general, the synthesized temperature and precipitation changes in southeastern China had relatively diverse hydrothermal combinations during the last 2000 years. However, it is noteworthy that the integrated precipitation sequence in southeastern China is weakly comparable to the sequence in northern China, reflecting great regional differences in historical precipitation changes. Thus, the forcing mechanisms might differ greatly from south to north in the monsoonal region of eastern China. Furthermore, the results suggest that large-scale atmosphere–ocean interactions, volcanic activities, and changes in solar radiation could have had significant effects on the climate and environment changes in southeastern China during the last 2000 years.

With the objective of carbon neutrality, renewable energy resources gradually become the main power supply, whose variability poses great challenges to the operation and optimization of the system, especially to the power distribution network. In order to solve the problem of reactive power caused by high penetration of renewable energy sources, a centralized optimization model is proposed, which takes reactive power optimization and “generation-network-load-storage” multi-energy integration into account. The model aims at optimizing the operating cost and minimizing network losses and carbon emissions of the system. Reactive power compensation, regulation of energy storage, and energy conversion are considered to achieve safe and low-carbon economic dispatch of the power and gas systems. An improved second-order cone relaxation method is used for the convex relaxation of non-linear equality constraints concerned with the distribution network. The switching capacity produced by discrete reactive power compensators can be exactly linearized by the application of the big M approach. The simulation results demonstrate that the proposed method could effectively compensate the reactive power required by the grid-connection point of wind turbine, coordinate the energy interaction between the power and gas, thus improving the stability and elasticity of the distribution network after integration of large-scale renewable energy sources, which helps promote the consumption of renewable energy.

The icing of wind turbine blade will seriously affect the power output of wind turbine and endanger the safe operation of wind turbine. Computational fluid dynamics (CFD) is used to study the icing characteristics of typical wind wing. Firstly, the impact characteristics of water droplets on NACA0012 type turbine under different attack angle of 0°,4°,8°are calculated. The calculated results are in good agreement with the experimental results, which shows that the calculation method is correct, and, the ice coating on the blade surface of typical wind turbine with different wind speed and temperature was simulated, and the variation trend of water collection coefficient and ice thickness with temperature and velocity was obtained. The results show that: 1) with the increase of wind speed, the ice thickness of blade surface increases and the icing adhesion area increases; 2) with the decrease of temperature, the ice thickness of blade surface increases; and 3) the anti-ice effect of S801 airfoil is obviously greater than that of S802 airfoil. The research result helps logically select turbine under low temperature conditions, providing reference for lowering the blade icing hazard.

The resource utilization of solid waste is an important way to achieve energy saving and emission reduction. A lauric acid (LA)/raw fly ash (RFA)-diatomite(DT)/carbon nanotubes(CNT) composite form-stable phase change materials (FSPCM) for thermal energy storage were prepared via simple direct impregnation method, in which LA, RFA-DT binary matrix and CNT were employed as phase change materials(PCMs), the supporting material, and thermal conductive additive, respectively. The loading capacity, structure and thermal properties of FSCPCM were investigated through the diffusion-oozing testing, Fourier transform infrared spectrometer (FTIR), differential scanning calorimetry (DSC), thermo gravimetry analysis (TGA) and paperless recorder, respectively. The results show that the RFA-DT binary material can effectively prevent the leakage of LA. When the mass fraction of LA in composite is 28%, the FSPCM without leakage can be obtained. What’s more, the utilization rate of RFA reaches 55%. The FTIR demonstrates that FSPCM has good compatibility between its four components, LA, RFA-DT, and CNT. The melting onset temperature of FSPCM is 45.79 ℃ measured by DSC, and the corresponding latent heat of FSPCM is determined as 51.06 J/g. TGA analysis shows LA/RFA-DT has good thermal stability. The storage/release performance curve indicates that when mass fraction of CNT is added with 5%, the melting and solidification time of LA/RFA-DT/CNT are decreased by 60% and 62.5%, respectively, indicating that the heat transfer performance is remarkably improved.