熔融碳酸盐燃料电池(MCFC)用γ-LiAlO_2粉末的制备

本文简介了熔融碳酸盐燃料电池(MCFC)及其优点;叙述了合成LiAlO_2的方法,用Al_2O_3(a,γ)成功地制得了稳定的适合于MCFC用的γ-LiAlO_2,在MCFC工作温度(923K)下,β-LiAlO_2是不稳定的;973-1073K时,β-LiAlO_2向γ-LiAlO_2转变速度明显增大;a-LiAlO_2要在1073K以上转变为γ-LiAlO_2.     

基于ANSYS的有限元网格划分方法

使用ANSYS软件分析实体模型的过程中,有限元网格划分是至关重要的一步.首先简单介绍了ANSYS软件的使用范围和核心思想,然后介绍了网格划分的基本步骤.最后结合实例详细说明了网格划分不同方法的技巧.     

Function of Graphene Oxide as the “Nanoquencher” for Hg2+ Detection Using an Exonuclease I-Assisted Biosensor

Graphene oxide is well known for its excellent fluorescence quenching ability. In this study, positively charged graphene oxide (pGO25000) was developed as a fluorescence quencher that is water-soluble and synthesized by grafting polyetherimide onto graphene oxide nanosheets by a carbodiimide reaction. Compared to graphene oxide, the fluorescence quenching ability of pGO25000 is significantly improved by the increase in the affinity between pGO25000 and the DNA strand, which is introduced by the additional electrostatic interaction. The FAM-labeled single-stranded DNA probe can be almost completely quenched at concentrations of pGO25000 as low as 0.1 μg/mL. A simple and novel FAM-labeled single-stranded DNA sensor was designed for Hg²⁺ detection to take advantage of exonuclease I-triggered single-stranded DNA hydrolysis, and pGO25000 acted as a fluorescence quencher. The FAM-labeled single-stranded DNA probe is present as a hairpin structure by the formation of T–Hg²⁺–T when Hg²⁺ is present, and no fluorescence is observed. It is digested by exonuclease I without Hg²⁺, and fluorescence is recovered. The fluorescence intensity of the proposed biosensor was positively correlated with the Hg²⁺ concentration in the range of 0–250 nM (R² = 0.9955), with a seasonable limit of detection (3σ) cal. 3.93 nM. It was successfully applied to real samples of pond water for Hg²⁺ detection, obtaining a recovery rate from 99.6% to 101.1%.     

Cytokinin Confers Brown Planthopper Resistance by Elevating Jasmonic Acid Pathway in Rice

Plants have evolved a sophisticated defense system that employs various hormone pathways to defend against attacks by insect pests. Cytokinin (CK) plays an important role in plant growth and stress tolerance, but the role of CKs in plant–insect interaction remains largely unclear. Here, we report that CKs act as a positive regulator in rice resistance against brown planthopper (BPH), a devastating insect pest of rice. We found that BPH feeding promotes CK biosynthesis and signaling in rice. Exogenous application of CKs significantly increased the rice resistance to BPH. Increasing endogenous CKs by knocking out cytokinin oxidase/dehydrogenase (OsCKXs) led to enhanced resistance to BPH. Moreover, the levels of the plant hormone jasmonic acid (JA) and the expression of JA-responsive genes were elevated by CK treatment and in OsCKXs knockout plants. Furthermore, JA-deficient mutant og1 was more susceptible to BPH, and CK-induced BPH resistance was suppressed in og1. These results indicate that CK-mediated BPH resistance is JA-dependent. Our findings provide the direct evidence for the novel role of CK in promoting insect resistance, and demonstrate that CK-induced insect resistance is JA-dependent. These results provide important guidance for effective pest management strategies in the future.     

Comprehensive Analysis of hsa-miR-654-5p’s Tumor-Suppressing Functions

The pivotal roles of miRNAs in carcinogenesis, metastasis, and prognosis have been demonstrated recently in various cancers. This study intended to investigate the specific roles of hsa-miR-654-5p in lung cancer, which is, in general, rarely discussed. A series of closed-loop bioinformatic functional analyses were integrated with in vitro experimental validation to explore the overall biological functions and pan-cancer regulation pattern of miR-654-5p. We found that miR-654-5p abundance was significantly elevated in LUAD tissues and correlated with patients’ survival. A total of 275 potential targets of miR-654-5p were then identified and the miR-654-5p-RNF8 regulation axis was validated in vitro as a proof of concept. Furthermore, we revealed the tumor-suppressing roles of miR-654-5p and demonstrated that miR-654-5p inhibited the lung cancer cell epithelial-mesenchymal transition (EMT) process, cell proliferation, and migration using target-based, abundance-based, and ssGSEA-based bioinformatic methods and in vitro validation. Following the construction of a protein–protein interaction network, 11 highly interconnected hub genes were identified and a five-genes risk scoring model was developed to assess their potential prognostic ability. Our study does not only provide a basic miRNA-mRNA-phenotypes reference map for understanding the function of miR-654-5p in different cancers but also reveals the tumor-suppressing roles and prognostic values of miR-654-5p.     

Engineering the Thermoelectrical Properties of PEDOT:PSS by Alkali Metal Ion Effect

Engineering the electrical properties of poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate)(PEDOT:PSS)holds great potential for various applications such a...     

cPCN-Regulated SnO2 Composites Enables Perovskite Solar Cell with Efficiency Beyond 23％

Efficient electron transport layers(ETLs)not only play a crucial role in promoting carrier separation and electron extraction in perovskite solar cells(PSCs)but...     

Growth mechanism for zinc coatings deposited by vacuum thermal evaporation

The vacuum thermal evaporation technique was used to simultaneously deposit zinc coatings onto interstitial free steel plates and single-crystal silicon wafers ...     

凯氏定氮仪在复混肥料总氮含量测定中的运用

我国是一个农业大国。农业的发展是国民经济和社会发展的重要因素。复混肥料在农业中的运用也日益广泛。文章研究的凯氏定氮仪法的检测方法与国标方法GB/T8572-2001的原理相同。与国标法比较,总氮含量的绝对误差在0.01%～0.29%之间,极差在0.07%～0.18%之间,检测准确度和精密度都符合国家标准的要求。此方法操作简便快速高效、安全可靠,效果令人满意。     

羧酸和乙酸酐合成甲基酮的研究

酮是化学化工行业应用广泛的重要中间体,其常见的合成方法这些年来不断有新的报道。文章研究了以常见的羧酸和乙酸酐为起始原料合成甲基酮的方法。该方法实施简单,产物收率62%～89%,为酮提供了一种未见文献报道的合成新方法。