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In view of a whole series of problems such as the reduction of system inertia， the increase of frequency fluctuation， and the deterioration of power quality caused by large-scale wind power integration， a flywheel with high power density is designed for energy storage in wind farm and connected to the low voltage side of the box type transformer for the purpose of peak and valley regulation， system inertia enhancement and frequency regulation. The converter on the side of the flywheel energy storage system adopts current vector control， so that the output power of the system can be flexibly adjusted. The grid-side converter adopts a voltage directional vector control strategy to ensure the stability of the DC bus voltage. In order to verify the operation reliability of the system， Mat lab/Simulink is used to build a simulation model for testing. The results show that the energy storage system is simple to operate， efficient and convenient for installation and construction； a rotation speed modular is designed based on the operation mechanism of flywheel energy storage so that the system can operate within safety domain efficiently； control schemes of current and voltage vector on the system side and grid side are formulated respectively so that the output power can be smooth and the voltage stable.

Astragalus, as the most commonly used traditional Chinese medicinal herb, contains various active components, the most important of which are astragaloside IV, flavonoids, and polysaccharides.These components endow Astragalus with a variety of pharmacological effects such as immunity enhancement, anti-fatigue, anti-inflammatory, cardiovascular and cerebrovascular protection, visceral tissue protection, anti-cancer, anti-tumor, etc.The article reviews the physiological functions of the active components of Astragalus and their application in food, with the aim of providing theoretical references for the further development and application of Astragalus and its active components in the food industry. [ABSTRACT FROM AUTHOR]

In order to evaluate the performance of precipitable water vapor (PWV) inversion from reanalysis data in specific areas and under specific weather conditions, an atmospheric weighted mean temperature model was established based on the observation data of Guilin radiosonde stations from 2015 to 2017. The continuous operating reference stations (CORS) precipitable water vapor (CORS-PWV) calculated by the model was used as the reference value, and was compared with the PWV extracted from the two reanalysis data ERAS and MERRA-2. The results show that compared with Bevis model, Guangxi model and Eastern China model, the accuracy of the new model is improved by 8.1%, 13.1% and 17.1%, respectively. In the course of a rainstorm, taking the CORS-PWV of day of year from 178-183 in 2017 as reference value, the mean bias and RMSE of PWV extracted by ERAS are 1.55 mm and 3.38 mm respectively, while the mean bias and RMSE of PWV extracted by MERRA-2 are -1.60 mm and 6.18 mm. The PWV extracted by ERAS has a better consistency with the PWV retrieved by CORS station, which is consistent with the actual ground precipitation situation. [ABSTRACT FROM AUTHOR]

Reducing CO2 emissions and increasing carbon sinks are basic approaches to achieve carbon neutralization in China. China is the largest mariculture country in the world. China's mariculture industry is dominated by non-fed culture type and characterized by rich species, diverse nutrition levels, and advanced farming technology. Therefore, mariculture has huge potential for the development of ocean negative carbon emissions (ONCE). However, the ONCE process of bivalves and seaweed farming is complicated, and the scientific principles, process, mechanisms, monitoring and evaluating methods, and approaches of increasing carbon sink are gradually being recognized and yet to be resolved. This study discusses the research progress of fishery carbon sink, existing problems and possible impact of global climate change on ONCE of mariculture. It then proposes technological approachs and policy suggestions to implement ONCE, which include expanding mariculture space and increaseing unit yield, green development of mariculture based on carrying capacity regulatory regime, integrated multi-trophic aquaculture, blue carbon engineering of ocean ranching, and marine artificial upwelling. [ABSTRACT FROM AUTHOR]

Daqing oilfield has entered the extra high water cut development stage after polymer flooding. There are some problems, such as low degree of water flooding control and big contradictions between layers, etc. In order to further dip remaining oil, improve recovery factor and solve the problem of injection-production exploitation, on the basis of indoor experiment, this paper studied parameter optimization of gel and polymer alternating injection after polymer flooding in view of N5 test area. The results show that the EOR effect of small slug with more rounds of gel and polymer alternating injection after polymer flooding is better than big slug with less rounds; best combination of slug is gel (0. 02 PV) + polymer (0. 03 PV) and total injection rounds are 11 (total 0. 55 PV). Under this condition, the stage recovery can increase about 10% than polymer flooding, which indicates that the method of gel and polymer alternating injection has the potential of further developing remaining oil after polymer flooding. [ABSTRACT FROM AUTHOR]

Financial support can effectively promote the construction and development of carbon trading market. However, the China's commercial banks generally neglect to address climate change. If these commercial banks were forced into the carbon trading market, it could promote the issue of green credit, enforcement of low carbon and transfer financing mode and low carbon financial products innovation, at the same time could increase the activity carbon trading market, promote carbon emissions responsibility way from the producer responsibility to shared responsibility. [ABSTRACT FROM AUTHOR]

Ranpirnase (onconase, ONC) is a new drug, with weak RNase activity and strong cytotoxicity to various tumor cells in vitro and in vivo. This study is to obtain recombination onconase (rONC) with high bioactivity. Based on the codon preference of Pichia pastoris, we designed and synthesized the gene according to cDNA sequences of ONC and the α mating factor's prepeptide. We screened positive clones after transforming the recombination plasmids into P. pastoris X-33, GSS115 and SMD1168. We screened the best combination of seven different vectors and host strains. Moreover, we optimized culture condition in shake flasks and 10 L bioreactor, and purified rONC from the supernatant after inducing it with 0.25% methanol by aqueous two-phase extraction coupling G50 molecular exclusion method. The highest rONC production was 13 mg/L in pPICZα-A/X-33/ONC combination under the condition of pH 5.5 and 23 degrees C in shake flasks for 7 d; and that the highest rONC production was 180 mg/L when the induction is performed in the lower basic salt medium with pH 5.5 in the 10 L bioreactor for 7 d. The yield of rONC is more than 90% at a purity of above 95%. rONC can kill various tumor cells in vitro. The expression and purification of rONC would be useful for further investigation of this new drug.

Objective: To explore the effects of acrylonitrile on T lymphocyte subsets, expression of toll-like receptor 4 and related cytokines in rats., Methods: Sixty-four Sprague-Dawley rats were randomly divided into 4 female groups and 4 male groups, and there were 8 rats in each group. Rats in each group were respectively given a single dose of 0, 5, 10 and 20 mg/kg acrylonitrile by gavage, once a day, 5 days a week, for 13 weeks. Blood and spleen T lymphocyte subsets was detected by flow cytometry, the mRNA expression of TLR4, IL-1β and TNF-α was analyzed by real-time quantitative PCR, the protein expression of TLR4 was evaluated by Western blot., Results: Compared with control group, the percentages of blood CD3, CD4 T cells in 20 mg/kg female group and CD4/CD8 ratio in 5, 10 and 20 mg/kg female groups was significantly decreased, CD8 T cells in 20 mg/kg group was significantly increased (P < 0.05 or P < 0.01), blood CD3 T cells in 5 mg/kg male group, CD4 T cells and CD4/CD8 ratio in 20 mg/kg male groups were lower than that of control group, CD8 T cells in 20 mg/kg make group was significantly in oreased (P < 0.05 or P < 0.01). Spleen CD4, CD8 T lymphocyte percentages and CD4/CD8 ratio in 20 mg/kg female group decreased significantly, CD8 T cells in 20 mg/kg male group was significantly increased (P < 0.05 or P < 0.01), spleen CD3, CD4, CD8 T cells in 20 mg/kg male group and CD4/CD8 ratio in 10, 20 mg/kg male groups was also significantly decreased, CD3 T cells in 20 mg/kg and CD8 T cells in 10, 20 mg/kg male groups were significantly increased (P < 0.05 or P < 0.01) (TLR4 mRNA was lower expressed in 5, 10 and 20 mg/kg male groups and 10 mg/kg female group (P < 0.05 or P < 0.01), and TLR4 protein in 5 mg/kg female group and 20 mg/kg male group was significantly lower than control group (P < 0.05). The expression level of IL-1β mRNA was significantly decreased in 5, 10 and 20 mg/kg female group and 5, 10 mg/kg male group (P < 0.05 or P < 0.01), TNF-α mRNA was lower expressed in 10, 20 mg/kg female groups and 5, 10 mg/kg male groups (P < 0.01)., Conclusion: Acrylonitrile may lead to the changes of CD3, CD4, CD8 T lymphocyte percentages and CD4/CD8 ratio in rat blood and spleen, and also significantly effected the expression level of TLR4 mRNA and protein together with the secretion of IL-1β, TNF-α. This may cause effects on the cellular immune function.

Aeromonas hydrophila (Ah) biofilm (BF) model in vitro was established and antibiotic effects of 11 antimicrobials on BF and free-cell(FC) bacteria were tested. After the Ah J-1 on the surfaces of the silicon pieces was incubated for 7 days in TSB, the intact BF was formed by detection of AgNO3 solution staining. The FC bacteria were resistant to Penicillin but susceptible to Enrofloxacin and Fulgram. Their minimum bactericidal concentrations (MBCs) were 256 microg/mL, 0.03 microg/mL and 0.25 microg/mL respectively. Florfenicol had a strong antibacterial effect on BF bacteria and the ratio of MBC between BF and FC bacteria was 2 to 1, but more than 32 to 1 occurred for Kanamycin, Penicillin and Neomycin. Morphology and structure of BFs with/without the treatment of Enrofloxacin were observed under scanning electron microscope, while the bactericidal curve was detected. Enrofloxacin could eradicate the FC bacteria completely but not the BF bacteria at a concentration of 4 fold MBC. The 32 fold MBC Enrofloxacin could entirely kill the FC bacteria in 4h, but in 24h for BF bacteria. The result suggested that BF enabled Ah to have strong resistance to antimicrobials and the potential influence of BF should be highly considered.