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Formation and evolution of supercritical geofluid

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Science China Earth Sciences 2025年第1期68卷 39-51页

作者： Huaiwei ni Yilin XIAO Xiaolin XIONG Xiandong liU Chunxiao GAO Yi-Xiang CHEN Yunguo li Wan-Cai li Xuan GUO Yang-Yang WANG Dong-Bo TAN li ZHANG State Key Laboratory of lithospheric and Environmental Coevolution University of Science and Technology of China Deep Space Exploration Laboratory/School of Earth and Space Sciences University of Science and Technology of China Guangzhou Institute of Geochemistry Chinese Academy of Sciences School of Earth Sciences and Engineering Nanjing University State Key Lab of Superhard Materials Jilin University

In this work, we provide a comprehensive review on the formation, evolution, properties, and effects of supercritical geofluid. In Earth's interior, enhanced miscibility between H2O and silicate by the addition of special components or by the increase of pressure and temperature gives rise to supercritical geofluid with a significant amount of both H2O and silicate *** formation of supercritical geofluid in magmatic-hydrothermal systems, typified by pegmatite system, is governed by meltfluid critical curve. The formation of supercritical geofluid in metamorphic systems, typified by subducted slab, is governed by the second critical end point. Experimental results suggest that the presence of boron and fluorine in pegmatite system makes it possible to form supercritical geofluid at crustal depths, but the release of supercritical geofluid from subducted slab is withheld until almost 100 km depth. A major presence of both H2O and depolymerized structural units（monomers, dimers, etc.） endows supercritical geofluid with unique physical properties including low density, low elastic moduli, low viscosity, high diffusivity,and high electrical conductivity. Supercritical geofluid can effectively mobilize a variety of elements even including high field strength elements and heavy rare earth elements. The chemical signatures of supercritical geofluid can be inherited by metasomatized mantle and mantle-derived melts, and this could give an explanation of the oxidation of arc magmas. Phase separation of supercritical geofluid through the mechanism of spinodal decomposition leads to formation of a melt network. Multiphase fluid inclusions recovered from subduction zone rocks and pegmatites are possible relics of supercritical geofluid. Supercritical geofluid can cause electrical anomaly and low seismic velocity near the top of subducted slab, and can be linked with intermediate-focus earthquakes. Supercritical geofluid may have played a crucial role in the formation of pe

关键词： Supercritical geofluid Miscibility Subduction zone Pegmatite

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新型肿瘤治疗靶点Cdc20的研究进展

药学学报 2017年第9期52卷 1366-1371页

作者：乐祥阳蒯梦妮李乾斌陈卓中南大学湘雅药学院湖南长沙410013

细胞分裂后期促进复合物(APC)具有调节细胞周期进展的作用,经细胞分裂周期蛋白20(Cdc20)或Cdc20同系物1(Cdh1)活化后形成两种不同的E3泛素连接酶复合物APC^(Cdc20)或APC^(Cdh1)。Cdc20为促癌因子,Cdh1为抑癌因子,在肿瘤的发生及发展中... 详细信息

细胞分裂后期促进复合物(APC)具有调节细胞周期进展的作用,经细胞分裂周期蛋白20(Cdc20)或Cdc20同系物1(Cdh1)活化后形成两种不同的E3泛素连接酶复合物APC^(Cdc20)或APC^(Cdh1)。Cdc20为促癌因子,Cdh1为抑癌因子,在肿瘤的发生及发展中发挥不同的作用。越来越多的研究表明,Cdc20对肿瘤的发生起促进作用,很多肿瘤中存在Cdc20的高表达。目前Cdc20抑制剂除了apcin外,大部分为非特异性抑制剂,不仅阻断Cdc20与APC的结合,也阻断Cdh1与APC的结合,选择性差。本文就Cdc20在肿瘤发生及发展过程中的作用及其抑制剂进行综述。

关键词：肿瘤细胞分裂周期蛋白20 E3泛素连接酶抑制剂

应用蒙特卡洛模拟评价头孢类抗菌药的给药方案

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中国药学杂志 2018年第9期53卷 725-728页

作者：王梦妮李芬芬李英超冉延涛李晓天郑州大学药学院郑州450000

目的依据药动/药效(PK/PD)原理,应用蒙特卡洛模拟评价及优化头孢类抗菌药物的给药方案。方法将临床常用静脉滴注头孢类药物头孢拉定、头孢呋辛、头孢曲松、头孢吡肟0.75 g qid、1 g qid、2 g bid、2 g tid 4种给药方案分别对大肠埃希菌... 详细信息

目的依据药动/药效(PK/PD)原理,应用蒙特卡洛模拟评价及优化头孢类抗菌药物的给药方案。方法将临床常用静脉滴注头孢类药物头孢拉定、头孢呋辛、头孢曲松、头孢吡肟0.75 g qid、1 g qid、2 g bid、2 g tid 4种给药方案分别对大肠埃希菌、阴沟肠杆菌、肺炎克雷白杆菌、鲍曼不动杆菌、枸橼酸杆菌、金黄色葡萄球菌、肺炎链球菌、铜绿假单胞菌进行最低抑菌浓度(MIC)测定及蒙特卡洛模拟,评价各给药方案疗效。结果头孢拉定、头孢呋辛的耐药率较高(47.31%~100%),累计反应分数(CFR)均小于90%;头孢呋辛对大肠埃希菌、肺炎克雷白杆菌、枸橼酸杆菌及肺炎链球菌均有可取的给药方案;头孢吡肟对8种菌株均有至少1种给药方案的CFR大于90%,并且符合时间依赖性药物特点。结论对于治疗病菌感染,在选用头孢类药物时应遵从抗生素使用原则。目标治疗应进行致病菌株药敏试验,根据MIC值模拟相应的给药方案,实现个体化给药。

关键词：头孢类抗菌药药动/药效蒙特卡洛模拟

Atmospheric reductive catalytic fractionation of lignocellulose integrated with one-pot catalytic conversion of carbohydrate yielding valuable lignin monomers and platform chemicals from corn straw

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Green Energy & Environment 2025年第1期10卷 161-172页

作者： meng-Ying liu Zhe-Hui Zhang Xue-Qi Wang Qian Sun Chen Zhang Yu li Zhuohua Sun Katalin Barta Feng Peng Tong-Qi Yuan State Key Laboratory of Efficient Production of Forest Resources Beijing Forestry UniversityBeijing100083China Beijing Key Laboratory of lignocellulosic Chemistry Beijing Forestry UniversityBeijing100083China Department of Chemistry Organic and Bioorganic ChemistryUniversity of GrazHeinrichstrasse 28/II8010 GrazAustria

Developing a cost-effective and environmentally friendly process for the production of valuable chemicals from abundant herbal biomass receives great attentions in recent ***,taking advantage of the“lignin first”strategy,corn straw is converted to valuable chemicals including lignin monomers,furfural and 5-methoxymethylfurfural via a two steps *** key of this research lies in the development of a green and low-cost catalytic process utilizing magnetic Raney ni catalyst and high boiling point ethylene *** utilization of neat ethylene glycol as the sole slovent under atmospheric conditions obviates the need for additional additives,thereby facilitating the entire process to be conducted in glass flasks and rendering it highly convenient for scaling *** the initial step,depolymerization of corn straw lignin resulted in a monomer yield of 18.1 wt%.Subsequently,in a dimethyl carbonate system,the carbohydrate component underwent complete conversion in a one-pot process,yielding furfural and 5-methoxymethylfurfural as the primary products with an impressive yield of 47.7%.

关键词： Atmospheric reductive catalytic fractionation Corn straw Ethylene glycol Raney ni 5-Methoxymethylfurfural

Effects of Ti-and Nb-based transition element from single to multiple compound oxides and carbon-based composite additives on Mg-MgH2 hydrogen storage material

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Tungsten 2025年第1期7卷 32-49页

作者： li-Rong Xiao Chen Chen Shuo Wang Zi-Yin Dai Hideo Kimura Cui ni Chuan-Xin Hou Xue-Qin Sun Si-Jie Guo Wei Du Xiu-Bo Xie School of Environmental and Material Engineering Yantai University Bosch HUAYU Steering Systems (Yantai) Co. Ltd.Ytp/MFE University of Tennessee Knoxville Shandong Key Laboratory of Eco-Environmental Science for the Yellow River Delta Shandong University of Aeronautics

MgH2is considered as a promising hydrogen storage material for its high hydrogen storage capacity,low cost and abundant resource ***,the low kinetics and high enthalpy formation of MgH2limit its wide *** the perspective of adding catalysts to enhance the hydrogen storage properties of Mg-MgH2,this article elaborated the main catalysts based on Ti and Nb transition elements,including single oxide catalysts,binary oxides catalysts（combined with ni,Na,Sr,V,etc.）,multiple catalysts bound to carbon,and composite catalysts with Ti and Nb elements combined with MXene ***,the main pathways of various catalysts to reduce the reaction activity and broaden the hydrogen desorption channel were also *** Ti-based catalysts can enhance the reactive sites of the matrix by forming multivalent states,while Nb-based catalysts broaden the hydrogen reaction channels by forming tiny *** improving the size structure and enhancing the grain size stability,combined with carbon materials should be the future considerations.

关键词： Catalysts Mg-based hydrogen storage alloys Solid hydrogen storage Transition metal elements

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贝类中不同种类病原生物的快速检测方法

生命科学研究 2013年第2期17卷 156-162页

作者：倪梦丽杨冰王春德吕昆仑侯伟青岛农业大学海洋科学与工程学院中国山东青岛266109 青岛出入境检验检疫局中国山东青岛266001 青岛机场出入境检验检疫局中国山东青岛266108

为适应进口鲜活贝类的快速检验需求,有必要建立快速检测多种病原生物的方法.针对进口鲜活水产品中常见的细菌、病毒和原生动物等不同种类的病原生物,设计了退火温度相近的特异PCR引物,建立了能够同时定性检测不同种类病原生物的方法.在... 详细信息

为适应进口鲜活贝类的快速检验需求,有必要建立快速检测多种病原生物的方法.针对进口鲜活水产品中常见的细菌、病毒和原生动物等不同种类的病原生物,设计了退火温度相近的特异PCR引物,建立了能够同时定性检测不同种类病原生物的方法.在此基础上,针对不同病原生物设计了特异的荧光引物,建立了检测贝类中不同病原生物的荧光定量PCR体系,并进行了特异性与重复性试验.与传统的检测方法相比较,该方法检测贝类中的病原生物更为快速准确,结果直观,可以满足口岸进口水产品快速检测的需要.

关键词：沙门氏菌派琴虫急性坏死性病毒(AVNV) 荧光定量PCR 贝类

Based on non-targeted metabolomics for differential components screening of Rosae Chinensis Flos and Rosae Rugosae Flos and their quality evaluation

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Traditional Medicine Research 2025年第2期10卷 1-15页

作者： Xu liang ni-Hui Zhang Zhi-Lai Zhan Guang-Lu Chang Yan Gao Xia li Wen-Yuan Gao School of Pharmaceutical Science and Technology Faculty of MedicineTianjin UniversityTianjin 300193China State Key Laboratory for Quality Ensurance and Sustainable Use of Dao-di Herbs China Academy of Chinese Medical SciencesBeijing 100700China Key Laboratory of Modern Chinese Medicine Resources Research Enterprises Tianjin 300402China

Background:Rosa chinensis *** Rosa rugosa *** not only of ornamental value,but also edible flowers and the flower buds have been listed in the Chinese Pharmacopoeia as traditional *** two plants have some differences in efficacy,but the flower buds are easily confused for similar *** addition,large-scale cultivation of ornamental rose flowers may lead to a decrease in the effective components of medicinal ***,it is necessary to study the chemical composition and make quality evaluation of Rosae Chinensis Flos(Yueji)and Rosae Rugosae Flos(Meigui).Methods:In this study,40 batches of samples including Meigui and Yueji from different regions in China were collected to establish high-performance liquid chromatography ***,the fingerprints data was analyzed using principal component analysis,hierarchical cluster analysis,and partial least squares discriminant analysis analysis chemometrics to obtain information on intergroup differences,and non-targeted metabolomic techniques were applied to identify and compare chemical compositions of samples which were chosen from groups with large *** compounds were screened by orthogonal partial least-squares discriminant analysis and S-plot,and finally multi-component quantification was performed to comprehensively evaluate the quality of Yueji and ***:The similarity between the fingerprints of 40 batches roses and the reference print R was 0.73 to 0.93,indicating that there were similarities and differences between the *** principal component analysis and hierarchical cluster analysis of fingerprints data,the samples from different origins and varieties were intuitively divided into four *** least-squares discriminant analysis analysis showed that Meigui and Yueji cluster into two categories and the model was reliable.A total of 89 compounds were identified by high resolution mass spectrometry,mainly were flavonoids and flavon

关键词： Rosa chinensis Jacq. Rosa rugosa Thunb. metabolomics chemometrics multiple component quantification quality evaluation

A dual-site Fe-based catalyst for efficient ammonia synthesis under mild conditions

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Science China Chemistry 2025年

作者： Shiyong Zhang Mingyuan Zhang Tianhua Zhang Jizhen Sun Jiaxin li Kailin Su Ruishao Mao Yanliang Zhou Xuanbei Peng Yangyu Zhang Jun ni Bingyu lin Xiuyun Wang lilong Jiang National Engineering Research Center of Chemical Fertilizer Catalyst Fuzhou University Qingyuan Innovation Laboratory

Achieving green ammonia （NH3） synthesis requires developing effective catalysts under mild ***,the competitive adsorption of N2and H2,as well as the strong binding of N-containing intermediates on the catalyst,greatly inhibits the active sites for efficient ***,we constructed a series of ZrH2-modified Fe catalysts with dual active sites to address these issues and realized efficient NH3synthesis under mild *** study shows that ZrH2can not only provide active sites for H2activation but also transfer electrons to Fe sites for accelerating *** interaction between Fe and ZrH2over 40ZrH2-Fe leads to a decrease in work function and a downward shift of the d-band center,which is conducive to N2activation and NH3desorption,*** utilization of distinct sites for activating different reactants can avoid the competitive adsorption of N2and H2,leading to excellent NH3synthesis activity of the 40 wt.%ZrH2-mediated Fe *** a result,40ZrH2-Fe exhibits a high NH3synthesis rate of 23.3 mmol g-1cath-1at 400°C and 1 MPa and robust stability during100 h time-on-stream.

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黄精多糖不依赖于LRP5激活信号通路调控成骨细胞分化

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中国组织工程研究 2017年第4期21卷 493-498页

作者：彭小明宗少晖曾高峰农梦妮杜力李珂珂何基琛施雄智吴云乐广西医科大学研究生学院广西壮族自治区南宁市530021 广西医科大学第一附属医院脊柱骨病外科广西壮族自治区南宁市530021 广西医科大学公共卫生学院广西壮族自治区南宁市530021

背景:前期研究发现,黄精多糖通过Wnt/β-catenin信号通路促进骨髓间充质干细胞成骨分化,但是其促进骨髓间充质干细胞成骨分化的作用及分子机制尚不明确。目的:探讨黄精多糖LRP5激活Wnt信号通路促进小鼠骨髓间充质干细胞向成骨细胞分化... 详细信息

背景:前期研究发现,黄精多糖通过Wnt/β-catenin信号通路促进骨髓间充质干细胞成骨分化,但是其促进骨髓间充质干细胞成骨分化的作用及分子机制尚不明确。目的:探讨黄精多糖LRP5激活Wnt信号通路促进小鼠骨髓间充质干细胞向成骨细胞分化的研究。方法:培养C57BL/6小鼠骨髓骨髓间充干细胞,构建LRP5干扰载体,转染C57BL/6小鼠骨髓间充质干细胞,转染后在荧光倒置显微镜下计算细胞荧光转染效率及Western Blot检测LRP5蛋白的表达。碱性磷酸酶、茜素红染色和Western Blot分析转染LRP5-siR NA病毒后小鼠骨髓间充质干细胞成骨能力的改变;RT-PCR及双荧光素酶检测黄精多糖对沉默LRP5的小鼠骨髓间充干细胞的成骨分化作用。结果与结论:(1)与对照组相比,LRP5转染组细胞显著降低细胞的矿化能力(Pnin及Osterix基因的表达(Pnin信号通路促进小鼠骨髓间充质干细胞向成骨细胞分化。

关键词：黄精属膜蛋白质类细胞分化骨质疏松组织工程组织构建骨细胞黄精多糖骨髓间充质干细胞成骨分化 Wnt/β-catenin通路病毒转染国家自然科学基金