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Accurate quantification of 3′-terminal 2′-O-methylated small RNAs by utilizing oxidative deep sequencing

《医学前沿（英文）》 2022年第16卷第2期页码 240-250 doi: 10.1007/s11684-021-0909-7

摘要： The continuing discoveries of novel classes of RNA modifications in various organisms have raised the need for improving sensitive, convenient, and reliable methods for quantifying RNA modifications. In particular, a subset of small RNAs, including microRNAs (miRNAs) and Piwi-interacting RNAs (piRNAs), are modified at their 3′-terminal nucleotides via 2′-O-methylation. However, quantifying the levels of these small RNAs is difficult because 2′-O-methylation at the RNA 3′-terminus inhibits the activity of polyadenylate polymerase and T4 RNA ligase. These two enzymes are indispensable for RNA labeling or ligation in conventional miRNA quantification assays. In this study, we profiled 3′-terminal 2′-O-methyl plant miRNAs in the livers of rice-fed mice by oxidative deep sequencing and detected increasing amounts of plant miRNAs with prolonged oxidation treatment. We further compared the efficiency of stem-loop and poly(A)-tailed RT-qPCR in quantifying plant miRNAs in animal tissues and identified stem-loop RT-qPCR as the only suitable approach. Likewise, stem-loop RT-qPCR was superior to poly(A)-tailed RT-qPCR in quantifying 3′-terminal 2′-O-methyl piRNAs in human seminal plasma. In summary, this study established a standard procedure for quantifying the levels of 3′-terminal 2′-O-methyl miRNAs in plants and piRNAs. Accurate measurement of the 3′-terminal 2′-O-methylation of small RNAs has profound implications for understanding their pathophysiologic roles in biological systems.

关键词： small RNAs 2′-O-methylation sequencing RT-qPCR

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Rh₂O₃/hexagonal CePO₄ nanocatalysts for N₂O decomposition

Huan Liu, Zhen Ma

《化学科学与工程前沿（英文）》 2017年第11卷第4期页码 586-593 doi: 10.1007/s11705-017-1659-6

摘要： Hexagonal CePO nanorods were prepared by a precipitation method and hexagonal CePO nanowires were prepared by hydrothermal synthesis at 150 °C. Rh(NO ) was then used as a precursor for the impregnation of Rh O onto these CePO materials. The Rh O supported on the CePO nanowires was much more active for the catalytic decomposition of N O than the Rh O supported on CePO nanorods. The stability of both catalysts as a function of time on stream was studied and the influence of the co-feed (CO , O , H O or O /H O) on the N O decomposition was also investigated. The samples were characterized by N adsorption-desorption, inductively coupled plasma optical emission spectroscopy, X-ray diffraction, transmission electron microscopy, X-ray photoelectron microscopy, hydrogen temperature-programmed reduction, oxygen temperature-programmed desorption, and CO temperature-programmed desorption in order to correlate the physicochemical and catalytic properties.

关键词： Rh₂O₃ CePO₄ N₂O decomposition

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Association of gene variants with juvenile amyotrophic lateral sclerosis

《医学前沿（英文）》 doi: 10.1007/s11684-023-1005-y

摘要： Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease characterized by progressive degeneration of motor neurons, and it demonstrates high clinical heterogeneity and complex genetic architecture. A variation within TRMT2B (c.1356G>T; p.K452N) was identified to be associated with ALS in a family comprising two patients with juvenile ALS (JALS). Two missense variations and one splicing variation were identified in 10 patients with ALS in a cohort with 910 patients with ALS, and three more variants were identified in a public ALS database including 3317 patients with ALS. A decreased number of mitochondria, swollen mitochondria, lower expression of ND1, decreased mitochondrial complex I activities, lower mitochondrial aerobic respiration, and a high level of ROS were observed functionally in patient-originated lymphoblastoid cell lines and TRMT2B interfering HEK293 cells. Further, TRMT2B variations overexpression cells also displayed decreased ND1. In conclusion, a novel JALS-associated gene called TRMT2B was identified, thus broadening the clinical and genetic spectrum of ALS.

关键词： TRMT2B amyotrophic lateral sclerosis mitochondrial complex I tRNA methylation reactive oxygen species

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Shape selective catalysis in methylation of toluene: Development, challenges and perspectives

Jian Zhou, Zhicheng Liu, Yangdong Wang, Dejin Kong, Zaiku Xie

《化学科学与工程前沿（英文）》 2018年第12卷第1期页码 103-112 doi: 10.1007/s11705-017-1671-x

摘要： Toluene methylation with methanol offers an alternative method to produce -xylene by gathering methyl group directly from C1 chemical sources. It supplies a “molecular engineering” process to realize directional conversion of toluene/methanol molecules by selective catalysis in complicated methylation system. In this review, we introduce the synthesis method of -xylene, the development history of methylation catalysts and reaction mechanism, and the effect of reaction condition in -selective technical process. If constructing -xylene as the single target product, the major challenge to develop -selective toluene methylation is to improve the -xylene selectivity without, or as little as possible, losing the fraction of methanol for methylation. To reach higher yield of -xylene and more methanol usage in methylation, zeolite catalyst design should consider improving mass transfer and afterwards covering external acid sites by surface modification to get short “micro-tunnels” with shape selectivity. A solid understanding of mass transfer will benefit realizing the aim of converting more methanol feedstock into -methyl group.

关键词： shape selective catalysis methylation of toluene

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Environmental pollution and DNA methylation: carcinogenesis, clinical significance, and practical applications

null

《医学前沿（英文）》 2015年第9卷第3期页码 261-274 doi: 10.1007/s11684-015-0406-y

摘要：

Environmental pollution is one of the main causes of human cancer. Exposures to environmental carcinogens result in genetic and epigenetic alterations which induce cell transformation. Epigenetic changes caused by environmental pollution play important roles in the development and progression of environmental pollution-related cancers. Studies on DNA methylation are among the earliest and most conducted epigenetic research linked to cancer. In this review, the roles of DNA methylation in carcinogenesis and their significance in clinical medicine were summarized, and the effects of environmental pollutants, particularly air pollutants, on DNA methylation were introduced. Furthermore, prospective applications of DNA methylation to environmental pollution detection and cancer prevention were discussed.

关键词： environmental pollution DNA methylation cancer biomarker diagnosis therapy prevention

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The stabilization effect of Al₂O₃ on unconventional Pb/SiO₂ catalyst

《化学科学与工程前沿（英文）》 2023年第17卷第10期页码 1423-1429 doi: 10.1007/s11705-023-2315-y

摘要： Similar to Sn, Pb located at the same group (IVA) in the periodic table of elements, can also catalyze propane dehydrogenation to propene, while a fast deactivation can be observed. To enhance the stability, the traditional carrier Al₂O₃ with a small amount, was introduced into Pb/SiO₂ catalyst in this study. It has been proved that Al₂O₃ can inhibit the reduction of PbO, and weaken the agglomeration and loss of Pb species due to its enhanced interaction with Pb species. As a result, 3Al15Pb/SiO₂ catalyst exhibits a much higher stability up to more than 150 h. In addition, a simple schematic diagram of the change of surface species on the catalyst surface after Al₂O₃ addition was also proposed.

关键词： Pb/SiO₂ Al₂O₃ propane dehydrogenation propene stability

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固体氧化物电解池共电解H₂O/CO₂研究进展

范慧,宋世栋,韩敏芳

《中国工程科学》 2013年第15卷第2期页码 107-112

摘要：本文介绍了固体氧化物电解池的结构特点及其用于H2O/CO2的共电解制备H2和CO的工作原理，综述了固体氧化物电解池的组成形式，以及单片电解池和电解池堆用于H2O/CO2共电解反应的国内外研究进展，并阐述了提高固体氧化物电解池共电解效率所亟需解决的问题

关键词：固体氧化物电解池 H₂O/CO₂共电解合成气电解效率水电解

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Al₂O₃-M_xO_y硬面陶瓷涂层的喷焊制备及性能研究

王飚,王宇栋,李慧玲,张自华

《中国工程科学》 2002年第4卷第9期页码 75-80

摘要：

在碳钢母材上，用氧乙炔焰喷焊镍包铝合金粉末制取预涂层，喷焊50% Al₂O₃+50% Ni的复合粉末制取过渡层，用等离子喷焊Al₂O₃ - M_xO_y复合粉末制取最终涂层。

关键词： Al₂O₃-M_xO_y 涂层等离子抗腐蚀抗磨损

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Optimization of the O/HO process with response surface methodology for pretreatment of mother liquor

《环境科学与工程前沿（英文）》 2021年第15卷第4期 doi: 10.1007/s11783-020-1371-5

摘要：

• Real ML-GFW with high salinity and high organics was degraded by O₃/H₂O₂ process.

关键词： High salinity High organic matters Gas field wastewater O₃/H₂O₂ Response surface methodology

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含稀释剂的Al-Cr₂O₃体系燃烧合成反应热力学分析与反应模型

张衍诚,潘冶,张传

《中国工程科学》 2004年第6卷第6期页码 63-67

摘要：

对含稀释剂Al203和Cr203的Al-Cr203体系燃烧合成反应进行了热力学计算与分析，讨论了起始反应温度T0、稀释剂Al2O3和Cr2O3的含量对绝热反应温度7^的影响，并得出T<

关键词：金属陶瓷燃烧合成 Al-Cr203体系热力学反应模型

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Effect of TiO 2 loading on the activity of V/TiO 2 -Al 2 O 3 in the catalytic oxidehydrogenation of ethylbenzene

Xiaohong LI, Wenying LI,

《化学科学与工程前沿（英文）》 2010年第4卷第2期页码 142-146 doi: 10.1007/s11705-009-0233-2

摘要： TiO-AlOmixed oxides with different compositions ranging from 40wt-% to 95wt-% of TiO were prepared by sol-gel method and impregnated with different amounts of VO. Supports and catalysts were characterized by X-ray diffraction (XRD), physisorption, temperature preprogrammed reduction (H-TPR), and ammonia temperature programmed desorption (NH-TPD). TiO content in the support had obvious effect on the crystal structure, texture characteristic, acid property, and catalytic activity in dehydrogenation of ethylbenzene (EB) with carbon dioxide. The highest catalytic activity was acquired when the TiO content was 50 wt-%.

关键词： desorption different TiO-AlOmixed physisorption ethylbenzene

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Study on tribological and electrochemistry properties of metal materials in H2O2 solutions

Chengqing YUAN, Li YU, Jian LI, Xinping YAN

《机械工程前沿（英文）》 2012年第7卷第1期页码 93-98 doi: 10.1007/s11465-012-0313-8

摘要：

Hydrogen peroxide (H₂O₂) is a kind of ideal green propellant. It is crucial to study the wear behavior and failure modes of the metal materials under the strong oxidizing environment of H₂O₂. This study aims to investigate the wear of rubbing pairs of 2Cr13 stainless steel against 1045 metal in H₂O₂ solutions, which has a great effect on wear, the decomposition and damage mechanism of materials. The comparison analysis of the friction coefficients, wear mass loss, worn surface topographies and current densities was conducted under different concentrations of H₂O₂ solutions. There were significant differences in the tribological and electrochemistry properties of the rubbing pairs in different H₂O₂ solutions.

关键词： hydrogen peroxide wear corrosion wear mechanism

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ZnFe₂O₄ deposited on BiOCl with exposed (001) and (010) facets for photocatalyticreduction of CO₂ in cyclohexanol

Guixian Song, Xionggang Wu, Feng Xin, Xiaohong Yin

《化学科学与工程前沿（英文）》 2017年第11卷第2期页码 197-204 doi: 10.1007/s11705-016-1606-y

摘要： ZnFe O -BiOCl composites were prepared by both hydrothermal and direct precipitation processes and the structures and properties of the samples were characterized by various instrumental techniques. The samples were then used as catalysts for the photocatalytic reduction of CO in cyclohexanol under ultraviolet irradiation to give cyclohexanone (CH) and cyclohexyl formate (CF). The photocatalytic CO reduction activities over the hydrothermally prepared ZnFe O -BiOCl composites were higher than those over the directly-precipitated composites. This is because compared to the direct-precipitation sample, the ZnFe O nanoparticles in the hydrothermal sample were smaller and more uniformly distributed on the surface of BiOCl and so more heterojunctions were formed. Higher CF and CH yields were obtained for the pure BiOCl and BiOCl composite samples with more exposed (001) facets than for the samples with more exposed (010) facets. This is due to the higher density of oxygen atoms in the exposed (001) facets, which creates more oxygen vacancies, and thereby improves the separation efficiency of the electron-hole pairs. More importantly, irradiation of the (001) facets with ultraviolet light produces photo-generated electrons which is helpful for the reduction of CO to ·CO . The mechanism for the photocatalytic reduction of CO in cyclohexanol over ZnFe O -BiOCl composites with exposed (001) facets involves electron transfer and carbon radical formation.

关键词： reduction of CO₂ cyclohexanol ZnFe₂O₄ deposited BiOCl facet composite photocatalyst

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Al₂O₃ and CeO₂-promoted MgO sorbents for CO₂ capture at moderate

Huimei Yu, Xiaoxing Wang, Zhu Shu, Mamoru Fujii, Chunshan Song

《化学科学与工程前沿（英文）》 2018年第12卷第1期页码 83-93 doi: 10.1007/s11705-017-1691-6

摘要： A series of Al O and CeO modified MgO sorbents was prepared and studied for CO sorption at moderate temperatures. The CO sorption capacity of MgO was enhanced with the addition of either Al O or CeO . Over Al O -MgO sorbents, the best capacity of 24.6 mg-CO /g-sorbent was attained at 100 °C, which was 61% higher than that of MgO (15.3 mg-CO /g-sorbent). The highest capacity of 35.3 mg-CO /g-sorbent was obtained over the CeO -MgO sorbents at the optimal temperature of 200 °C. Combining with the characterization results, we conclude that the promotion effect on CO sorption with the addition of Al O and CeO can be attributed to the increased surface area with reduced MgO crystallite size. Moreover, the addition of CeO increased the basicity of MgO phase, resulting in more increase in the CO capacity than Al O promoter. Both the Al O -MgO and CeO -MgO sorbents exhibited better cyclic stability than MgO over the course of fifteen CO sorption-desorption cycles. Compared to Al O , CeO is more effective for promoting the CO capacity of MgO. To enhance the CO capacity of MgO sorbent, increasing the basicity is more effective than the increase in the surface area.

关键词： CO₂ capture MgO sorbents Al₂O₃ CeO₂ flue gas

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NiCo2O4@quinone-rich N–C core–shell nanowires as composite electrode for electric double layer capacitor

《化学科学与工程前沿（英文）》 2023年第17卷第4期页码 373-386 doi: 10.1007/s11705-022-2223-6

摘要： The bind-free carbon cloth-supported electrodes hold the promises for high-performance electrochemical capacitors with high specific capacitance and good cyclic stability. Considering the close connection between their performance and the amount of carbon material loaded on the electrodes, in this work, NiCo₂O₄ nanowires were firstly grown on the substrate of active carbon cloth to provide the necessary surface area in the longitudinal direction. Then, the quinone-rich nitrogen-doped carbon shell structure was formed around NiCo₂O₄ nanowires, and the obtained composite was used as electrode for electric double layer capacitor. The results showed that the composite electrode displayed an area-specific capacitance of 1794 mF∙cm^–2 at the current density of 1 mA∙cm^–2. The assembled symmetric electric double layer capacitor achieved a high energy density of 6.55 mW∙h∙cm^–3 at a power density of 180 mW∙cm^–3. The assembled symmetric capacitor exhibited a capacitance retention of 88.96% after 10000 charge/discharge cycles at the current density of 20 mA∙cm^–2. These results indicated the potentials in the preparation of the carbon electrode materials with high energy density and good cycling stability.

关键词： carbon cloth NiCo₂O₄ nanowires core−shell structure quinone-rich electric double layer capacitor