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71.
提出一种电感电流、输出电压瞬时值反馈控制和负载电流前馈控制相结合的复合控制策略。在此基础上,研制了一台800W的单相逆变器。实验结果表明,提出的控制策略改善了逆变器输出电压的波形,提高了系统的暂态特性。 相似文献
72.
A current development trend in research on intelligent systems is to optimize a general intelligent prediction system into an individuation intelligent prediction system that is applied in specialized fields. Protein structure prediction is a challenging international issue. In this paper, we propose a new intelligent prediction system model, designed as a multi-layer compound pyramid model, for predicting secondary protein structure. The model comprises four independent intelligent interfaces and several knowledge discovery methods. The model penetrates throughout the domain knowledge, with the effective attributes chosen by Causal Cellular Automata. Furthermore, a high pure structure database is constructed for training. On the RS126 dataset, the overall state per-residue accuracy, Q3, reached 83.99%, while on the CB513 dataset, Q3 reached 85.58%. Meanwhile, on the CASP8 sequences, the results are superior to those produced by other methods, such as Psipred, Jpred, APSSP2 and BehairPred. These results confirm that our method has a strong generalization ability, and that it provides a model for the construction of other intelligent systems. 相似文献
73.
74.
Novel technology of purification of copper electrolyte 总被引:10,自引:1,他引:10
The effects of arsenic with different valence states on the purification of copper electrolyte were studied and a novel technology of purification of copper electrolyte by copper arsenite was proposed. The results show that the purification performance of As(Ⅲ) compounds is better than that of As(Ⅴ) compounds. The purification technology by copper arsenite has the advantages of simple operation, high purification performance and low cost in comparison with other technologies and its appropriate purification conditions are that copper arsenite concentration is 18 g/L, reaction temperature is 65 ℃ and reaction time is 8 h. The removal rates of Sb and Bi are 53.22% and 58.67% respectively under these conditions. The purification principle show that a kind of yellow precipitate mainly composed of arsenic, antimony ( Ⅴ ), bismuth and oxygen forms in electrolyte after copper arsenite is added, and consequently antimony and bismuth are removed from electrolyte. 相似文献
75.
Jang Mi Han Jae Kyung Sohng Woo-Haeng Lee Tae-Jin Oh Hye Jin Jung 《International journal of molecular sciences》2021,22(5)
We recently discovered a novel nargenicin A1 analog, 23-demethyl 8,13-deoxynargenicin (compound 9), with potential anti-cancer and anti-angiogenic activities against human gastric adenocarcinoma (AGS) cells. To identify the key molecular targets of compound 9, that are responsible for its biological activities, the changes in proteome expression in AGS cells following compound 9 treatment were analyzed using two-dimensional gel electrophoresis (2-DE), followed by MALDI/TOF/MS. Analyses using chemical proteomics and western blotting revealed that compound 9 treatment significantly suppressed the expression of cyclophilin A (CypA), a member of the immunophilin family. Furthermore, compound 9 downregulated CD147-mediated mitogen-activated protein kinase (MAPK) signaling pathway, including c-Jun N-terminal kinase (JNK) and extracellular signal-regulated protein kinase 1/2 (ERK1/2) by inhibiting the expression of CD147, the cellular receptor of CypA. Notably, the responses of AGS cells to CypA knockdown were significantly correlated with the anticancer and antiangiogenic effects of compound 9. CypA siRNAs reduced the expression of CD147 and phosphorylation of JNK and ERK1/2. In addition, the suppressive effects of CypA siRNAs on proliferation, migration, invasion, and angiogenesis induction of AGS cells were associated with G2/M cell cycle arrest, caspase-mediated apoptosis, inhibition of MMP-9 and MMP-2 expression, inactivation of PI3K/AKT/mTOR pathway, and inhibition of hypoxia-inducible factor-1α (HIF-1α) and vascular endothelial growth factor (VEGF) expression. The specific interaction between compound 9 and CypA was also confirmed using the drug affinity responsive target stability (DARTS) and cellular thermal shift assay (CETSA) approaches. Moreover, in silico docking analysis revealed that the structure of compound 9 was a good fit for the cyclosporin A binding cavity of CypA. Collectively, these findings provide a novel molecular basis for compound 9-mediated suppression of gastric cancer progression through the targeting of CypA. 相似文献
76.
采用苯酚、邻苯二酚、愈创木酚和紫丁香酚为木质素单体模化物,利用两段裂解反应器-在线气相色谱仪(GCs)进行热解实验和产物分析,采用多色谱柱对无机气体(IGs)、C1~C5烃(C1~C5 LHs)、非芳基含氧化合物、酚和芳烃进行定量分析,以确定羟基和甲氧基对木质素热解过程中开环反应及产物分布的影响. 结果显示:羟基和甲氧基可以提高模化物的转化率,且羟基和甲氧基的存在影响芳基开环反应、芳基取代反应和重排反应间的竞争关系,使热解产物分布存在明显差异. 4种模化物热解产物主要是芳环的开环反应产物,包括IGs(质量分数为27.29%~33.56%)和C1~C5烃(20.46%~39.51%). 一氧化碳产率(23.82%~29.18%)随羟基数增加而升高,随甲氧基数增加而降低;二氧化碳产率(0.19%~9.61%)随甲氧基数增加而升高. 羟基和甲氧基的存在降低了C1~C5烃的质量选择性,促进了烷基苯、大分子化合物和焦炭的形成. 相似文献
77.
WAVE FIELD EXTRAPOLATION IN VISCOELASTIC MEDIUM AND VARIABLE FOCUS METHOD TO SEPARATE SEISMIC COMPOUND WAVE 总被引:2,自引:0,他引:2
WAVEFIELDEXTRAPOLATIONINVISCOELASTICMEDIUMANDVARIABLEFOCUSMETHODTOSEPARATESEISMICCOMPOUNDWAVE¥SongShougen;YuanXiugui;HeJishan... 相似文献
78.
从热力学第二定律出发, 指出清洁生产的热力学本质是控制物质由有序结构向无序转化并从中获取最大效益, 其优劣可由过程熵增反映。 引用复杂体系非平衡定态过程最小熵产生原理,推导出依据与外界交换的物流和热流信息定量计算化工复杂系统过程熵增的方法, 并定义过程熵增指数ζ 。 评价了化工过程对环境热力学状态的综合影响。选择以硫和以氨为载能原料的磷复肥工艺为例进行了计算和对比,其过程熵增指数分别为6.753和4.571,反映出载能原料硫作为废物排放对环境热力学状态产生更大的影响。 相似文献
79.
[目的]解决30%三唑锡悬浮剂分散稳定性的问题。[方法]为提高30%三唑锡悬浮剂分散稳定性,采用流点法对不同类型的分散剂进行初步筛选并测试表面张力,通过测试SC粒径、Zeta电势、悬浮率、流变性能确定分散剂配比与用量并对分散稳定机理进行分析。[结果]与单一分散剂制备SC相比,聚羧酸盐分散剂SD-816和聚氧乙烯醚磷酸酯分散剂SD-208复配体系制备的SC性能较优,其表观黏度、Zeta电势、粒径和悬浮率分别为386 mPa·s、-37.2 mV、2.58μm及98.4%。并且提出了聚羧酸盐分散剂和聚氧乙烯醚磷酸酯分散剂对农药三唑锡可能的分散机理。[结论]聚羧酸盐SD-816和聚氧乙烯醚磷酸酯SD-208的复配体系可同时提供静电排斥作用和空间位阻,明显改善SC体系的悬浮稳定性。 相似文献
80.
[目的]开发吡唑醚菌酯悬浮剂,并对较优配方中表面活性剂复配性能进行研究。[方法]采用湿法研磨工艺,通过粒径及稳定性等指标的测试,对配方中的润湿分散剂、增稠剂和防冻剂等进行了筛选,并采用表面张力法对表面活性剂组合的复配性能进行了研究。[结果]当表面活性剂8561与G5000的用量为5%和1%时,即摩尔比为4:1时,可制得合格的15%和25%吡唑醚菌酯悬浮剂。在该比例下,2种表面活性剂具有强烈的相互作用,与宏观现象相符。[结论]将复配表面活性剂协同增效理论与农药悬浮剂的研制相结合,对农药制剂研究工作有一定的指导意义。 相似文献