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“如果”句功能的类型学考察

汉语学习 2024年第2期 22-32页

作者：吴炳章姜彩璨许冰中国海洋大学外国语学院山东青岛266100

“如果”句的语义结构和用法复杂多样,但学界对该结构的功能类型分析过于笼统。文章通过语料库梳理书面语中“如果”句的结构特点和语篇关系,对其进行了功能分类。从功能视角看,“如果”句在知识域、语言域和人际域中分别发挥前提限定... 详细信息

“如果”句的语义结构和用法复杂多样,但学界对该结构的功能类型分析过于笼统。文章通过语料库梳理书面语中“如果”句的结构特点和语篇关系,对其进行了功能分类。从功能视角看,“如果”句在知识域、语言域和人际域中分别发挥前提限定、语篇建构和会话修辞等功能。根据从句和主句的意义关系,“如果”句可以分为蕴含条件句和非蕴含条件句。各类“如果”句的功能各有句法语义特征。从各类“如果”句的用法分布看,“如果”句的主要功能是表达推理关系,其次是语篇关系,再次是话语修辞。

关键词： “如果”句假设条件句间接条件句

Realizing efficient electrochemical oxidation of 5-hydroxymethylfurfural on a freestanding ni(OH)_(2)/nickel foam catalyst

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Chinese Journal of Catalysis 2024年第8期63卷 282-291页

作者： Yunying Huo Cong Guo yongle zh.ng Jingyi Liu Qiao zh.ng zhiting Liu Guangxing Yang Rengui Li Feng Peng School of Chemistry and Chemical Engineering Guangzhou UniversityGuangzhou 510006GuangdongChina State Key Laboratory of Catalysis Dalian National Laboratory for Clean EnergyDalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023LiaoningChina

With the continuous improvement of solar energy production capacity,how to effectively use the electricity generated by renewable solar energy for electrochemical conversion of biomass is a hot *** conversion of 5-hydroxymethylfurfural(HMF)to biofuels and value-added oxygenated commodity chemicals provides a promising and alternative pathway to convert re-newable electricity into *** nickel-based eletrocatalysts are well-known for HMF oxidation,their relatively low intrinsic activity,poor conductivity and stability still limit the poten-tial ***,we report the fabrication of a freestanding nickel-based electrode,in which ni(OH)2 species were in-situ constructed on ni foam(nF)support using a facile ac-id-corrosion-induced *** ni(OH)2/nF electrocatalyst exhibits stable and efficient electro-chemical HMF oxidation into 2,5-furandicarboxylic acid(FDCA)with HMF conversion close to 100%with high Faraday ***-situ formation strategy results in a compact interface between ni(OH)2 and nF,which contributes to good conductivity and stability during electrochemical *** superior performance benefits from dynamic cyclic evolution of ni(OH)2 to niOOH,which acts as the reactive species for HMF oxidation to FDCA.A scaled-up device based on a continu-ous-flow electrolytic cell was also established,giving stable operation with a high FDCA production rate of 27 mg h^(-1)cm^(−2).This job offers a straightforward,economical,and scalable design strategy to design efficient and durable catalysts for electrochemical conversion of valuable chemicals.

关键词： Acid-corrosion-induced 5-Hydroxymethylfurfural Electrocatalytic oxidation ni electrocatalysis

EFFECT　OF　RARE　EARTH　ELEMEnT　Er　On　STREnGTHEnInG　OF　InTERFACE　OF　Ti（C，n）　BASED　CERMETS

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中国有色金属学会会刊：英文版 1996年第3期6卷 136-139页

作者： Liu, n Cui, K Hu, zh AnHUI InST TECHnOL DEPT MAT SCI & ENGNHEFEI 230069PEOPLES R CHINA HUAzh.nG UnIV SCI & TECHnOL WUHAN 430074PEOPLES R CHINA

ＥＦＦＥＣＴＯＦＲＡＲＥＥＡＲＴＨＥＬＥＭＥＮＴＥｒＯＮＳＴＲＥＮＧＴＨＥＮＩＮＧＯＦＩＮＴＥＲＦＡＣＥＯＦＴｉ（Ｃ，Ｎ）ＢＡＳＥＤＣＥＲＭＥＴＳ￥ＬｉｕＮｉｎｇ（ＤｅｐａｒｔｍｅｎｔｏｆＭａｔｅｒｉａｌｓＳｃｉｅｎ... 详细信息

ＥＦＦＥＣＴＯＦＲＡＲＥＥＡＲＴＨＥＬＥＭＥＮＴＥｒＯＮＳＴＲＥＮＧＴＨＥＮＩＮＧＯＦＩＮＴＥＲＦＡＣＥＯＦＴｉ（Ｃ，Ｎ）ＢＡＳＥＤＣＥＲＭＥＴＳ￥ＬｉｕＮｉｎｇ（ＤｅｐａｒｔｍｅｎｔｏｆＭａｔｅｒｉａｌｓＳｃｉｅｎｃｅａｎｄＥｎｇｉｎｅｅｒｉｎｇ，...

关键词： rare earth element Er Ti(C n) based cermets bending strength hardness

MECHAnICAL PROPERTIES AnD MICROSTRUCTURES OF Ti(C,n) BASED CERMETS

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中国有色金属学会会刊：英文版 1996年第4期6卷 117-121页

作者： Liu, n Hu, zh Cui, K Liu, CL AnHUI InST TECHnOL DEPT MAT SCI & ENGNHEFEI 230069PEOPLES R CHINA HUAzh.nG UnIV SCI & TECHnOL WUHAN 430074PEOPLES R CHINA BEIJInG GEn RES InST IROn & STEEL BEIJING 100081PEOPLES R CHINA

ＭＥＣＨＡＮＩＣＡＬＰＲＯＰＥＲＴＩＥＳＡＮＤＭＩＣＲＯＳＴＲＵＣＴＵＲＥＳＯＦＴｉ（Ｃ，Ｎ）ＢＡＳＥＤＣＥＲＭＥＴＳ￥ＬｉｕＮｉｎｇ（ＤｅｐａｒｔｍｅｎｔｏｆＭａｔｅｒｉａｌｓＳｃｉｅｎｃｅａｎｄＥｎｇｉｎｅｅｒｉ... 详细信息

ＭＥＣＨＡＮＩＣＡＬＰＲＯＰＥＲＴＩＥＳＡＮＤＭＩＣＲＯＳＴＲＵＣＴＵＲＥＳＯＦＴｉ（Ｃ，Ｎ）ＢＡＳＥＤＣＥＲＭＥＴＳ￥ＬｉｕＮｉｎｇ（ＤｅｐａｒｔｍｅｎｔｏｆＭａｔｅｒｉａｌｓＳｃｉｅｎｃｅａｎｄＥｎｇｉｎｅｅｒｉｎｇ，ＡｎｈｕｉＩｎｓｔｉｌｕｔｅ...

关键词： Ti(C,n) based cermets mechanical properties microstructure

Silicotungstic acid-derived WO_(3) composited with ZrO_(2) supported on SBA-15 as a highly efficient mesoporous solid acid catalyst for the alkenylation of p-xylene with phenylacetylene

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Chinese Chemical Letters 2022年第3期33卷 1325-1330页

作者： Xueting Bai yongle Guo zh.ngkui zhao State Key Laboratory of Fine Chemicals Department of Catalysis Chemistry and EngineeringSchool of Chemical EngineeringDalian University of TechnologyDalian 116024China

Highly dispersed silicotungstic acid-derived WO_(3) composited with ZrO_(2) supported on SBA-_(15) (WZ/SBA-_(15)) as an ordered mesoporous solid acid catalyst was prepared via a facile incipient wetness impregnation (IWI) method that active ingredients, ZrO_(2) and WO_(3), were impregnated into the channels of SBA-_(15) simultaneously with a subsequent calcination process. The relationship between catalyst nature and performance was explored by high resolution transmission electron microscopy (HRTEM), high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM), FT-IR, X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), n_(2) adsorption-desorption, nH_(3) temperature-programmed desorption (nH_(3)-TPD), and FT-IR of pyridine adsorption (Py-IR) characterization techniques. The catalytic performance of W_(12)Z_(15)/SBA-_(15) is not only greater than that of single component solid acid catalysts, WO_(3)/SBA-_(15) and ZrO_(2)/SBA-_(15), but also W_(12)/Z_(15)/SBA-_(15) prepared by impregnating active ingredients, ZrO_(2) and WO_(3), into SBA-_(15) in sequence. The outstanding performance of W_(12)Z_(15)/SBA-_(15) is derived from the strong interaction between ZrO_(2) and WO_(3), which results in more acid sites, and relatively high specific surface area, large pore volume, and ordered mesoporous structure of SBA-_(15). The characterization and reaction results clearly demonstrate that the synergy of ZrO_(2) and WO_(3) has a clear boost for the alkenylation. The optimized W_(12)Z_(15)/SBA-_(15)-500 achieves a 99.4% conversion of phenylacetylene and a 92.3% selectivity of main product α-arylstyrene for the alkenylation of p-xylene with phenylacetylene, with very low level of oligomers producing at the same time. Moreover, W_(12)Z_(15)/SBA-_(15)-500 shows excellent catalytic stability and regeneration. Therefore, W_(12)Z_(15)/SBA-_(15)-500 is a promising solid acid catalyst for the alkenylation.

关键词： Alkenylation SBA-15 Zirconium dioxide Tungsten trioxide Silicotungstic acid Solid acid

Excellent magnetic softness in TbFe/FeCoV multilayers

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Rare Metals 2011年第4期30卷 322-326页

作者： FEnG Tangf LI yongle CHEn Ziyu Department of Physics Beihang University Beijing 100191 China Key Laboratory of Micro-nano Measurement-Manipulation and Physics （Ministry of Education of China） Beihang University Beijing 100191 China

[Tb4oFe6o（x nm）/Fe49Co49V2（y nm）]n multilayers were prepared by multitarget magnetron sputtering using a rotary turn-table technique in a stop-and-go mode. The mulfilayers were investigated using X-ray diffraction, field emission scan electron microscopy and vibrating sample magnetometry. The result shows that the coercive field drops abruptly with increasing number of bilayers, and it remains generally stable when the number of bilayers is 10 or higher. An excellent magnetic softness with a coercivity of 1.0 mT is obtained for x = 5 and y = 5 after annealing at 250℃. A crystalline state is observed in FeCoV layers before and after annealing by X-ray diffraction.

关键词： rnagnetostdctive devices multiplayer films magnetic softness magnetron sputtering coercivity

Master equation,design equations and runaway speed of the Kaplan turbine

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Journal of Hydrodynamics 2021年第2期33卷 282-300页

作者： zh.zh.ng zhAW Zurch University of Applied ScienceZurichSwitzerland

To make the Kaplan turbine technology comparable to both the Pelton and the Francis turbine,the master equation for the Kaplan turbine has been established by analyses similar to that-for the Francis *** analysis begins with the descriptions of free vortex flows at the runner inlet and the swirl flow at the impeller *** considering the Euler equation for specific work and by further evaluating the most significant shock and swirling losses,the first and the second energy equations in the form of hydraulic efficiency were *** master equation is then established by combining both energy *** addition,three design equations and a new design parameter are *** master equation relates the turbine hydromechanics to the geometrical design of both the runner and the guide-vane *** enables the complete hydraulic characteristics of a given Kaplan turbine to be analytically and simply computed.A computation example demonstrates the functionality and applicability of the *** the reconstructed master equation,the runaway speed of the Kaplan turbine and its dependence on the guide-vane setting can be easily and precisely *** bulb turbines with guide vanes directly ahead of the turbine runner in the same tube,all computations are also applicable using another equivalent control parameter.

关键词： Kaplan turbine master equation design equations design parameter runaway speed hydraulic efficiency shock loss swirling loss bulb turbines

经阴道超声血流参数联合血清抗苗勒管激素对多囊卵巢综合征不孕症体外受精-胚胎移植妊娠失败的预测价值

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实用临床医药杂志 2024年第4期28卷 125-130,135页

作者：张金玲李永乐河南省生殖妇产医院/河南省生殖健康科研院超声科河南郑州450003 河南省生殖妇产医院/河南省生殖健康科研院生殖医学中心河南郑州450003

目的探讨经阴道超声血流参数联合血清抗苗勒管激素(AMH)对多囊卵巢综合征(PCOS)不孕症体外受精-胚胎移植(IVF-ET)妊娠失败的预测价值。方法选取行IVF-ET的173例PCOS不孕症患者为研究对象,其中脱落12例。根据胚胎移植后第28天阴道B超结果... 详细信息

目的探讨经阴道超声血流参数联合血清抗苗勒管激素(AMH)对多囊卵巢综合征(PCOS)不孕症体外受精-胚胎移植(IVF-ET)妊娠失败的预测价值。方法选取行IVF-ET的173例PCOS不孕症患者为研究对象,其中脱落12例。根据胚胎移植后第28天阴道B超结果将161例患者分为妊娠失败组(n=96)与妊娠成功组(n=65)。比较2组阻力指数(RI)、搏动指数(PI)、收缩与舒张末期最大血流速度比值(S/D)和血清AMH水平。采用多因素Logistic回归分析法分析PCOS不孕症IVF-ET妊娠失败的影响因素。绘制受试者工作特征(ROC)曲线,分析RI、PI、S/D、血清AMH水平单独及联合评估对PCOS不孕症患者IVF-ET妊娠失败的预测价值。结果妊娠失败组血清AMH水平低于妊娠成功组,血流RI、PI、S/D高于妊娠成功组,差异有统计学意义(P<0.001)。RI(OR=4.688,95%CI:2.878~6.498)、PI(OR=4.332,95%CI:2.277~6.387)、S/D(OR=3.773,95%CI:1.856~5.691)、月经第3天黄体生成素(LH)/促卵泡生成素(FSH)值(OR=2.998,95%CI:1.236~4.760)高是PCOS不孕症IVF-ET妊娠失败的危险因素(P<0.05);月经第3天FSH水平高(OR=0.579,95%CI:0.416~0.806)、血清AMH水平高(OR=0.722,95%CI:0.533~0.911)及人绒毛膜促性腺激素(hCG)日子宫内膜厚(OR=0.632,95%CI:0.421~0.843)是PCOS不孕症IVF-ET妊娠失败的保护因素(P<0.05)。RI、PI、S/D联合血清AMH水平预测PCOS不孕症IVF-ET妊娠失败的灵敏度、特异度、曲线下面积(AUC)分别为95.83%、80.00%、0.933。结论超声血流参数联合AMH对PCOS不孕症IVF-ET妊娠失败具有较好的预测价值。

关键词：超声血流参数血清抗苗勒管激素多囊卵巢综合征不孕症体外受精-胚胎移植

马蓝AP2/ERF转录因子家族全基因组鉴定与表达分析

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植物生理学报 2024年第9期60卷 1461-1474页

作者：胡永乐黄杨钦王天才宁书菊叶齐魏道智武夷学院生态与资源工程学院福建省生态产业绿色技术重点实验室福建武夷山354300 福建农林大学生命科学学院福州350002 武夷学院海峡成功学院福建武夷山354300 福建农林大学农学院福州350002

马蓝中吲哚类生物碱靛蓝、靛玉红具有药效物质和天然色素的双重价值属性,经济及社会效益较高。AP2/ERF转录因子家族可从转录水平调控次生代谢物合成,本研究利用生物信息学从马蓝基因组中鉴定获得205个AP2/ERF转录因子,不均匀分布在16条... 详细信息

马蓝中吲哚类生物碱靛蓝、靛玉红具有药效物质和天然色素的双重价值属性,经济及社会效益较高。AP2/ERF转录因子家族可从转录水平调控次生代谢物合成,本研究利用生物信息学从马蓝基因组中鉴定获得205个AP2/ERF转录因子,不均匀分布在16条染色体上。结合结构域特征及系统进化分析,将成员细分为28个AP2亚家族、103个ERF亚家族、65个DREB亚家族、7个RAV亚家族和2个Soloist亚家族。保守基序及基因结构分析表明, Motif 1、2、4、5广泛分布于马蓝AP2/ERF中,部分亚家族具有自身特异Motif,各组别内含子/外显子结构具有一致性。物种间共线性分析表明, 49.8%的马蓝AP2/ERF在拟南芥中存在同源基因对。结合转录组筛选出响应茉莉酸甲酯诱导的组织差异表达基因,为后续探究AP2/ERF转录因子在马蓝吲哚类生物碱合成调控中的作用提供参考。

关键词： AP2/ERF转录因子转录因子家族生物信息学吲哚类生物碱