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61.
The progress of aqueous zinc batteries (AZBs) is limited by the poor cycling life due to Zn anode instability, including dendrite growth, surface corrosion, and passivation. Inspired by the anti-corrosion strategy of steel industry, a compounding corrosion inhibitor (CCI) is employed as the electrolyte additive for Zn metal anode protection. It is shown that CCI can spontaneously generate a uniform and ≈30 nm thick solid-electrolyte interphase (SEI) layer on Zn anode with a strong adhesion via Zn O bonding. This SEI layer efficiently prohibits water corrosion and guides homogeneous Zn deposition without obvious dendrite formation. This enables reversible Zn deposition and dissolution for over 1100 h under the condition of 1 mA cm−2 and 1 mAh cm−2 in symmetric cells. The Zn-MnO2 full cells with CCI-modified electrolyte deliver an ultralow capacity decay rate (0.013% per cycle) at 0.5 A g−1 over 1000 cycles. Such an innovative strategy paves a low-cost way to achieve AZBs with long lifespan.  相似文献   
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The silkworm Bombyx mori L. is a model organism of the order Lepidoptera. Understanding the mechanism of pesticide resistance in silkworms is valuable for Lepidopteran pest control. In this study, comparative metabolomics was used to analyze the metabolites of 2 silkworm strains with different pesticide resistance levels at 6, 12, and 24 h after feeding with fenpropathrin. Twenty-six of 27 metabolites showed significant differences after fenpropathrin treatment and were classified into 6 metabolic pathways: glycerophospholipid metabolism, sulfur metabolism, glycolysis, amino acid metabolism, the urea cycle, and the tricarboxylic acid (TCA) cycle. After analyzing the percentage changes in the metabolic pathways at the 3 time points, sulfur metabolism, glycolysis, and the TCA cycle showed significant responses to fenpropathrin. Confirmatory experiments were performed by feeding silkworms with key metabolites of the 3 pathways. The combination of iron(II) fumarate + folic acid (IF-FA) enhanced fenpropathrin resistance in silkworms 6.38 fold, indicating that the TCA cycle is the core pathway associated with resistance. Furthermore, the disruption of several energy-related metabolic pathways caused by fenpropathrin was shown to be recovered by IF-FA in vitro. Therefore, IF-FA may have a role in boosting silkworm pesticide resistance by modulating the equilibrium between the TCA cycle and its related metabolic pathways.  相似文献   
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65.
Oresitrophe and Mukdenia (Saxifragaceae) are epilithic sister genera used in traditional Chinese medicine. The taxonomy of Mukdenia, especially of M. acanthifolia, has been controversial. To address this, we produced plastid and mitochondrial data using genome skimming for Mukdenia acanthifolia and Mukdenia rossii, including three individuals of each species. We assembled complete plastomes, mitochondrial CDS and nuclear ribosomal ETS/ITS sequences using these data. Comparative analysis shows that the plastomes of Mukdenia and Oresitrophe are relatively conservative in terms of genome size, structure, gene content, RNA editing sites and codon usage. Five plastid regions that represent hotspots of change (trnH-psbA, psbC-trnS, trnM-atpE, petA-psbJ and ccsA-ndhD) are identified within Mukdenia, and six regions (trnH-psbA, petN-psbM, trnM-atpE, rps16-trnQ, ycf1 and ndhF) contain a higher number of species-specific parsimony-informative sites that may serve as potential DNA barcodes for species identification. To infer phylogenetic relationships between Mukdenia and Oresitrophe, we combined our data with published data based on three different datasets. The monophyly of each species (Oresitrophe rupifraga, M. acanthifolia and M. rossii) and the inferred topology ((M. rossii, M. acanthifolia), O. rupifraga) are well supported in trees reconstructed using the complete plastome sequences, but M. acanthifolia and M. rossii did not form a separate clade in the trees based on ETS + ITS data, while the mitochondrial CDS trees are not well-resolved. We found low recovery of genes in the Angiosperms353 target enrichment panel from our unenriched genome skimming data. Hybridization or incomplete lineage sorting may be the cause of discordance between trees reconstructed from organellar and nuclear data. Considering its morphological distinctiveness and our molecular phylogenetic results, we strongly recommend that M. acanthifolia be treated as a distinct species.  相似文献   
66.
用gFM31探针进行谷子品种的指纹分析   总被引:3,自引:0,他引:3  
王志民  刘春吉 《遗传学报》1996,23(3):228-233
用高度多态性探针gFM31对59个谷子(SetariaitarlicaBeauv.)品种(包括地方品种、育成品种及品系)进行DNA指纹分析,共鉴别出58种类型,而黑谷和黑粒1516给出完全相同的带型,二者有可能是同一材料。通过对gFM31DNA序列分析,未发现其中有小卫星DNA和微卫星DNA序列。该探针虽在谷子品种中显示很高的多态性,但与禾谷类的其他物种的DNA杂交信号微弱,表现出较强的谷子基因组特异性。  相似文献   
67.
A rapid method for microorganism detection using a piezoelectric quartz crystal sensor (PQC) coated with a thin liquid culture medium film was developed and applied to detect the cell number of Proteus vulgaris. This method employed the viscosity and density response of PQC and utilized the coagulation of gelatine medium solution in which the microorganisms had grown to determine the microorganism indirectly. Three time points (TT1, DT, TT2) were obtained from the coagulation curve and were found to be in good linear relationship with the logarithm of the initial number of P. vulgaris in the range 1·3 × 102−1·3 × 105 cells/ml. The detection was rapid and accurate because the coagulation of the thin liquid culture medium film was quick and the time points in the response curve were sharp and so were easy to determine accurately. The detection time was less than 4 h and only a micro sample was needed. A 5 h preincubation was needed before detection. Some experimental conditions are discussed in detail.  相似文献   
68.
将实验大鼠放置模拟5000m海拔高度低压舱内1、2和4周。结果表明:与对照组比较,1,2和4周组动物的心肌重量分别增加15%,18%和57%;心肌SRCa2+摄取分别降低33%,38%和53%;心肌SRCa2+ATPase活性分别降低54%,60%和74%;钙泵mRNA含量(基因表达分别降低14%,46%和68%。这些结果提示,缺氧导致的SR钙泵功能降低可能是心肌功能受损的重要生化基础之一,而钙泵数目减少可能是钙泵功能降低的分子生物学机制。  相似文献   
69.
通过野生种分离选用的平菇丰收一号,染色体数为9(n=9),菌丝生长速度比一般品种快2—34cm/h,平均投料0.5kg(块)产鲜菇0.6~2.5kg,个别单株重10~20kg左右,生物效率100~150%,高者达200%以上,是一种高产优质、适应性强的新菌种。  相似文献   
70.
本实验用受体放射自显影方法,研究了新生大鼠辣椒素皮下注射,成年后脊髓内3H-埃托菲(3H-etorphine)结合位点数的变化。发现新生鼠辣椒素处理可以引起脊髓后角浅层及中央管周围’H-etorphine结合位点明显减,其中Ⅰ、Ⅱ层自显影银粒数减少36%左右。Ⅲ层减少20%,中央管周围减少11%。而前角及背外测束3H-etorphine结合位点数无显著性差异。结果表明脊髓内初级感觉传入细纤维上有阿片受体分布。本研究为探明阿片类物质在脊髓水平的痛觉调控机制提供一定的形态学依据。  相似文献   
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