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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

Zn-Al-Zr LDH/氧化石墨烯对水中草甘膦的去除研究

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中国陶瓷 2024年第7期60卷 28-35页

作者：任建辉熊昆李冬梅西南科技大学环境友好能源材料国家重点实验室绵阳621010 西南科技大学材料与化学学院绵阳621010 南通环安智能科技有限公司南通226000

采用氯化锌、六水合氯化铝、八水合氧氯化锆和氧化石墨烯为原料,氢氧化钠和一水合碳酸钠为碱溶液,通过共沉淀法合成Zn-Al-Zr LDH/Go纳米复合材料(LDH/Go)。XRD、SEM、BET和UV-Vis分光光度计,分别用于表征Zn-Al-Zr LDH/Go复合材料的物相... 详细信息

采用氯化锌、六水合氯化铝、八水合氧氯化锆和氧化石墨烯为原料,氢氧化钠和一水合碳酸钠为碱溶液,通过共沉淀法合成Zn-Al-Zr LDH/Go纳米复合材料(LDH/Go)。XRD、SEM、BET和UV-Vis分光光度计,分别用于表征Zn-Al-Zr LDH/Go复合材料的物相组成、微观形貌、孔隙结构和吸附过程。结果表明:Go的掺入可以改善LDH的形貌结构,当温度在303 K,pH=7,投料量为0.5g/L,LDH/Go对草甘膦的吸附容量可达10.707 mg/g;其吸附过程符合准二级动力学和Freundlich等温吸附模型,LDH/Go对草甘膦的去除机理为静电吸引和表面络合;其草甘膦吸附性能优于当前商业磷吸附产品Phoslock。因此,Zn-Al-Zr LDH/Go可作为一种有前景的草甘膦去除剂。

关键词：层状双金属氢氧化物石墨烯去除草甘膦

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早期康复护理对吉兰-巴雷综合征患者肌力及日常生活活动能力的影响

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罕少疾病杂志 2024年第8期31卷 148-149,158页

作者：位亚娟王静张新勋郑州大学第一附属医院神经重症监护病房河南郑州450052

目的探究早期康复护理在吉兰-巴雷综合征(GBS)患者中的应用效果。方法选取2021年1月~2023年12月本院收治的GBS患者72例,根据护理方案进行分组,对照组40例患者进行常规护理,观察组32例患者进行早期康复护理。比较两组的四肢肌力、日常生... 详细信息

目的探究早期康复护理在吉兰-巴雷综合征(GBS)患者中的应用效果。方法选取2021年1月~2023年12月本院收治的GBS患者72例,根据护理方案进行分组,对照组40例患者进行常规护理,观察组32例患者进行早期康复护理。比较两组的四肢肌力、日常生活活动能力、自我效能感以及生活质量。结果干预前两组患者各项指标之间均无显著性差异(P>0.05);干预后,观察组上、下肢近端及远端肌力、改良Barthel指数(MBI)、一般自我效能感量表(GSES)、简明健康状况问卷(SF-36)评分较对照组均明显升高(P<0.05)。结论在GBS患者中,应用早期康复护理可明显改善其四肢肌力,显著提升患者的日常生活活动能力,有效提高患者的自我效能感及生活质量,值得临床推广。

关键词：早期康复护理 GBS 肌力日常生活活动能力

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重庆市农业科技创新能力评价研究

生产力研究 2024年第6期 43-48,F0003页

作者：曾琼万立志尹朝静马强重庆生产力促进中心(重庆市科学技术信息中心) 重庆401147 西南大学经济管理学院重庆400715 重庆市农业科学院重庆401329

根据农业科技创新内涵以及农业科技创新发展目标要求,从农业科技创新环境、投入、产出和贡献四个方面构建重庆市农业科技创新能力评价指标体系,并对2022年重庆市37个行政区县(不含渝中区)的农业科技创新能力进行评价和分析。研究发现重... 详细信息

根据农业科技创新内涵以及农业科技创新发展目标要求,从农业科技创新环境、投入、产出和贡献四个方面构建重庆市农业科技创新能力评价指标体系,并对2022年重庆市37个行政区县(不含渝中区)的农业科技创新能力进行评价和分析。研究发现重庆市农业科技创新的主要特征和短板,并从强化科研创新供给、提高农业科技成果量、发展数字农业农村、提高农业科技智慧度等5个方面提出提升重庆市农业科技创新能力的建议。

关键词：数实融合理论机理路径选择重庆市

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复杂环境下铀的光电催化分离研究进展

核化学与放射化学 2024年第4期46卷 281-298,I0001页

作者：林涛何嵘陈涛张浩雨钟连兵竹文坤西南科技大学国防科技学院核废物与环境安全省部共建协同创新中心核环境安全技术创新中心环境友好能源材料国家重点实验室四川绵阳621010 四川东树新材料公司四川德阳618000

作为核电运行最重要的燃料,铀是保障核能可持续发展的关键。我国铀资源的供需矛盾逐年突出,缺口部分需要由境外开发与国际市场采购来保障。一方面,海水中的铀储量是陆地的近千倍;另一方面,核工业开采及生产应用过程产生大量的含铀放射... 详细信息

作为核电运行最重要的燃料,铀是保障核能可持续发展的关键。我国铀资源的供需矛盾逐年突出,缺口部分需要由境外开发与国际市场采购来保障。一方面,海水中的铀储量是陆地的近千倍;另一方面,核工业开采及生产应用过程产生大量的含铀放射性废水。若能实现海水和含铀放射性废水中铀的高效分离回收,对降低铀资源对外依存度、实现核能的可持续发展具有重要战略意义。本文聚焦于近年来在海水和含铀放射性废水等复杂体系中光催化提铀和电催化提铀的最新研究进展,总结了在光催化还原和电催化还原过程中催化剂的结构设计、功能改性策略以及催化机理,介绍了用于有效识别和监测铀催化反应中间过程的先进表征技术,并讨论了光催化还原与电催化还原技术面临的挑战和未来的发展方向。

关键词：铀资源海水提铀放射性废水提铀光催化电催化

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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.zhang 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

Master equation and runaway speed of the Francis turbine

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Journal of Hydrodynamics 2018年第2期30卷 203-217页

作者： zh.zhang Free Researcher Zurich Switzerland

The master equation of the Francis turbine is derived based on the combination of the angular momentum（Euler） and the energy laws. It relates the geometrical design of the impeller and the regulation settings（guide vane angle and rotational speed） to the discharge and the power output. The master equation, thus, enables the complete characteristics of a given Francis turbine to be easily computed. While applying the energy law, both the shock loss at the impeller inlet and the swirling loss at the impeller exit are taken into account. These are main losses which occur at both the partial load and the overloads and, thus, dominantly influence the characteristics of the Francis turbine. They also totally govern the discharge of the water through the impeller when the impeller is found in the standstill. The computations have been performed for the discharge, the hydraulic torque and the hydraulic efficiency. They were also compared with the available measurements on a model turbine. Excellent agreement has been achieved. The computations also enable the runaway speed of the Francis turbine and the related discharge to be determined as a function of the setting angle of the guide vanes.

关键词： Francis turbine master equation runaway speed hydraulic efficiency shock loss swirling loss streamline similarity method

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Journal of Hydrodynamics 2018年第1期30卷 140-152页

作者： zh.zhang Free Researcher Zurich Switzerland

An analytical method is presented, which enables the non-uniform velocity and pressure distributions at the impeller inlet of a pump to be accurately computed. The analyses are based on the potential flow theory and the geometrical similarity of the streamline distribution along the leading edge of the impeller blades. The method is thus called streamline similarity method（SSM）. The obtained geometrical form of the flow distribution is then simply described by the geometrical variable G（s） and the first structural constant G_Ⅰ. As clearly demonstrated and also validated by experiments, both the flow velocity and the pressure distributions at the impeller inlet are usually highly non-uniform. This knowledge is indispensible for impeller blade designs to fulfill the shockless inlet flow condition. By introducing the second structural constant G_Ⅱ, the paper also presents the simple and accurate computation of the shock loss, which occurs at the impeller inlet. The introduction of two structural constants contributes immensely to the enhancement of the computational accuracies. As further indicated, all computations presented in this paper can also be well applied to the non-uniform exit flow out of an impeller of the Francis turbine for accurately computing the related mean values.

关键词： Pumps streamline similarity method flow distribution shock loss structural constant

SUBSTRUCTURE PRECoNDITIoNERS FoR NoNCoNFoRMING PLATE ELEMENTS

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Journal of Computational Mathematics 1998年第4期16卷 289-304页

作者： Shi, ZC Xie, zh Chinese Acad Sci ICMSEC State Key Lab Sci & Engn Comp Beijing 100080 Peoples R China Chinese Acad Sci Inst Atmospher Phys LASG Beijing 100080 Peoples R China

In this paper, we consider the problem of solving finite element equations of biharmonic Dirichlet problems. We divide the given domain into non-overlapping subdomains, construct a preconditioner for Morley element by substructuring on the basis of a function decomposition for discrete biharmonic functions. The function decomposition is introduced by partitioning these finite element functions into the low and high frequency components through the intergrid transfer operators between coarse mesh and fine mesh, and the conforming interpolation operators. The method leads to a preconditioned system with the condition number bounded by C(1 + log(2) H/h) in the case with interior cross points, and by C in the case without interior cross points, where H is the subdomain size and h is the mesh size. These techniques are applicable to other nonconforming elements and are well suited to a parallel computation.

关键词： substructure preconditioner biharmonic equation nonconforming plate element