基于材料应变的新型装配式剪力墙变形指标限值

为研究新型装配式剪力墙的抗震性能及其变形指标限值,基于课题组所做新型装配式剪力墙抗震性能试验,采用析因法,共设计216个不同剪跨比、轴压比、边缘构件纵筋配筋率等新型装配式剪力墙模型,完成相应的单推性能研究;基于有限元破坏形态识别,将构件破坏形态划分为弯曲破坏、弯剪破坏和剪切破坏3类,提出墙体破坏形态划分准则。参考GB 50011—2010《建筑抗震设计规范》,对弯曲破坏和弯剪破坏划分6个性能状态,对剪切破坏划分两个性能状态,基于构件极限状态下混凝土、钢筋应变和承载力,确定墙体性能状态判定准则。通过线性回归分别得到弯曲破坏、弯剪破坏和剪切破坏形态下构件各塑性位移角限值的回归方程,并提出各破坏形态下具有90%保证率的构件变形指标限值标准,为基于性能的新型装配式剪力墙抗震设计提供参考。

关键元素超常富集与战略资源效应

构成战略资源的关键元素有56个,大部分关键元素地壳丰度低,需要数十倍至上千倍的超常富集才能成矿,导致其矿产资源分布极不均匀。因此,圈定元素超常富集区是战略资源找矿预测和发现大型矿床的关键。超常富集核心是元素的富集强度,可以用成矿富集系数(m.a.i)、矿床规模吨位指数(t.a.i)和异常富集系数(a.c.i)定量刻画富集强度。对贵金属、有色金属、黑色金属、稀有金属、稀散金属、稀土和放射性等35个战略资源矿种进行统计分析,可以得出:成矿富集系数大于1000的元素有锑、铋、铼和金,>100~1000的元素有银、钨、锡、铬、锂、铯、碲、铟、铀和铂族元素(PGE),>10~100的元素有铜、镍、铬、铍、铷、钪、铌、钽、锆和原生稀土矿,≤10的元素有铁、铝、钛和离子吸附型稀土。富集达到大型以上矿床最低矿床规模吨位指数要达到10^(7),一般要达到10^(10)。异常富集系数要达到2以上。元素超常富集还体现在异常空间分布面积>100~1000 km^(2),具有3层以上异常结构,至少存在4个元素组合。元素富集量和潜在资源量,可以用面金属量和体金属量进行定量预测。元素超常富集导致大规模成矿效应,而且在成矿物质背景(源)、成矿过程(运)和最终就位(储)整个富集过程中留下了异常轨迹,可以从定性和定量角度刻画元素超常富集规律,为预测和发现矿床提供找矿标志。

Distribution, Enrichment and Ecological Risk Assessment of Six Elements in Bed Sediments of a Tropical River, Chottanagpur Plateau: A Spatial and Temporal Appraisal

Distribution and enrichment of six elements (iron, zinc, copper, lead, cadmium and manganese) in surface bed sediments, collected from seventeen selected locations during pre-monsoon and postmonsoon periods, of the tropical Chottanagpur plateau river Subarnarekha along with the ecological risks involved were investigated. Owing to the rich occurrence of mineral resources, the Subarnarekha river basin has a large scale presence of industrial and mining units especially in the Indian State of Jharkhand. An assessment, which involved examining distribution pattern of elements, comparative studies with sediment quality guidelines (SQGs) and geochemical background values and a sequential and integrated index analyses approach (containing contamination factor (CF), pollution load index (PLI), contamination degree (CD), enrichment factor (EF), geo-accumulation index (Igeo) and potential ecological risk index (PERI)), was followed to estimate enrichment and risks of elements in the bed sediments. Sediments collected from areas having abundance of population, industrial conglomerates and mining units recorded elevated element concentrations, which exceeded SQGs, and significantly higher values of CF, CD, PLI, EF, Igeo and PERI. Cadmium demonstrated surprising regularity in its enrichment;contributed most to the ecological risks;and high toxicity risks due to cadmium exceeded 64% of the sites. Moreover, chronic exposures of other elements would also lead to similar ecological risks. In addition to revealing potential ecological risks due to cadmium and other elements our investigation markedly highlighted anthropogenic control over sediment quality deterioration and some immediate sediment quality management strategies are needed to remediate and control river bed contamination.

Stiffness degradation-based damage model for RC members and structures using fiber-beam elements

To meet the demand for an accurate and highly efficient damage model with a distinct physical meaning for performance-based earthquake engineering applications, a stiffness degradation-based damage model for reinforced concrete （RC） members and structures was developed using fiber beam-column elements. In this model, damage indices for concrete and steel fibers were defined by the degradation of the initial reloading modulus and the low-cycle fatigue law. Then, section, member, story and structure damage was evaluated by the degradation of the sectional bending stiffness, rod-end bending stiffness, story lateral stiffness and structure lateral stiffness, respectively. The damage model was realized in Matlab by reading in the outputs of OpenSees. The application of the damage model to RC columns and a RC frame indicates that the damage model is capable of accurately predicting the magnitude, position, and evolutionary process of damage, and estimating stow damage more precisely than inter-story drift. Additionally, the damage model establishes a close connection between damage indices at various levels without introducing weighting coefficients or force-displacement relationships. The development of the model has perfected the damage assessment function of OpenSees, laying a solid foundation for damage estimation at various levels of a large-scale structure subjected to seismic loading.

Analysis and evaluation of enterprise risk management capability elements

Research on enterprise risk management capability is conducted with a view of discerning and processing risks, in which an evaluation index system and an evaluation model of enterprise risk management capabilities are constructed. The risk management capability consists of four aspects, i.e. risk identification capability, risk assessment capability, risk planning capability and risk control capability. Risk identification and assessment capabilities reflect the level of enterprises on finding and analyzing risks efficiently, while risk planning and control capabilities reflect the level of enterprises on resolving risks effectively. Each of capabilities is then further divided into more detailed elements based on the characteristics of enterprise development for a quantitative analysis of enterprise risk management capability. The approach adopted is a quantitative technique based on the use of fuzzy comprehensive evaluation. Finally, a case is pulled in to illustrate the feasibility of the method from an empirical perspective. This study is expected to be helpful for enterprises in cultivating their core capabilities.

Expert Anti-Evaluation Model Based on Matter-Element Analysis in Fund Project Peer-Review System

The article analyses several key issues which restrict the effectiveness of fund project peer review work. It analyses the evaluating theory and matter-element theory to access the expert anti-evaluation model, and also studies the expert anti-evaluation index system to support the anti-evaluation method. The practical basis is the true score data of the experts which is collected from the actual anti-evaluation in Liaoning province science and technology fund project peer review system. With the practical experience of the actual project, we prove that the expert index system anti-evaluation model and expert anti-evaluation method can improve the fund project peer review work and play a positive role for the peer review work and also make the review work more scientific and more rational.

Definition and Application of Topological Index Based on Bond Connectivity

Bond connectivity topological index S i based on chemical bonds was defined by using a matrix method.And S i is formed by atomic parameters such as the number of valence electrons,the number of the highest main quantum of atoms and the bonding electrons and bond parameters such as the length of bonds,the electronegativity difference of bonding atoms.The molecular bond connectivity topological index S is composed of S i.The thermodynamic properties of saturated hydrocarbons,unsaturated hydrocarbons,oxygen organic,methane halide and transitional element compounds and the molecular bond connectivity topological index S have an optimal correlative relationship.

知识复杂性的测度方法综述与比较

[研究目的]复杂知识是突破关键核心技术的基础支撑,也是企业或区域建立竞争优势的关键要素。该文旨在全面把握知识复杂性测度方法的研究现状与前沿进展,为知识复杂性的深入研究提供测度理论基础。[研究方法]通过梳理国内外知识复杂性研究的相关文献,详细介绍三种主要的知识复杂性测度方法的核心思想、理论基础和计算过程,并进一步对比分析不同方法的适用层次和优缺点,最后提出未来研究方向。[研究结论]反射法主要基于知识的空间分布异质性间接衡量知识复杂性,虽然原理简单且操作相对容易,但无法揭示知识复杂性的本质特征;元素依赖性指数利用知识组合频次衡量知识元素之间的相互依赖程度,进而反映知识复杂性,忽视了其他影响知识组合的因素;结构多样性指数通过知识组合网络拓扑结构的多样性反映知识复杂性,综合考虑多个网络结构指标,并经过大量数值模拟检验,但存在估计结果不稳定、仅适用于二值网络等问题。

走出师德评价困境:新时期高校师德师风综合评价指标研究

当前高校师德师风评价的主要困境在于评价指标缺乏整体性、过程简单化和人文性不足。其原因包括对师德师风内涵的研究不够充分、对综合评价指标的研究有待提高等。基于一系列有关高校师德建设工作的文件,确定高校师德师风综合评价指标。该综合评价指标提出高校师德师风建设过程中需要具备的“要素”性指标,即包括“结构性要素”“能动性要素”“连接性要素”和“文化性要素”,弥补以往高校师德评价指标借用政策性文件内容未能起到价值引领和科学评价的不足。

Major and Trace Element Characterization of Shallow Groundwater in Coastal Alluvium of Chidambaram Town, Cuddalore District, South India

Hydrogeochemical investigation of groundwater of Chidambaram town has been carried out to assess the suitability for drinking uses and the source for the ions acquisition process. Geologically, the area comes under the alluvial zone and is followed by tertiary formation, includes sands, sand stone, laterite, clayey black and stiff clay. The water level varies from 6 m to 10 m bgl. Twenty groundwater samples are collected and analysed for pH, Electrical Conductivity (EC), Total Dissolved Solids (TDS), major cations Ca2+, Mg2+, Na+, K+ and anions , Cl-, . The trace elements of Zn, Pb, Cr, Fe, Cd, Cu and Mn are determined. Study results reveal that groundwater in study area is a fresh water type. The pH, EC and TDS are noticed high and sequence of abundance of the major ions is Ca2+ > Na+ > Mg2+ > K+ and Cl- > > . The Stufzand chloride classification indicates that the groundwater is derived from precipitations and Scholler classification shown type I. Hydrochemical facies of groundwater are Ca2+ > Na+ > Cl- and saturation index shows that nearly all the water samples are under saturated with respect to carbonate (calcite, dolomite and aragonite) and sulfate (gypsum and anhydrite) minerals. Except Zn, other elements of Fe, Pb, Cr, Mn, Cu, and Cd are found high and above the permissible limit of drinking water standard. The ionic concentration present in the groundwater of the study area can be from wastes of commercial activities, domestic sewage and automobiles rather than by ionic exchange and geological formation.

圆筒混合机内不同粒径颗粒的轴向分离研究

为了探讨颗粒在圆筒混合机的轴向分离机理,提出了一种由多段摩擦系数不同圆筒组成的新型圆筒混合机结构.以颗粒堆积角为参考,通过仿真与实验测试得到了颗粒的参数,并基于圆筒混合机分离实验验证了仿真模型.以此为基础,开展基于离散元法的不同粒度颗粒在圆筒混合机内分离过程的数值模拟研究,根据颗粒分布、休止角、运动速度、回转半径等分析了不同粒径颗粒在分离过程中的流动形态,并基于分离指数探讨颗粒的分离特性.结果表明:圆筒混合机侧壁摩擦系数不同将导致颗粒休止角不同,从而使不同区间颗粒的运动速度不同,高摩擦系数区域内颗粒运动快,而低摩擦系数区域内颗粒运动较慢;运动速度的不同导致颗粒在新型圆筒混合机内将产生明显的轴向分离现象,小粒径颗粒聚集在低摩擦系数区,而大粒径颗粒聚集在高摩擦系数区.

Potentially Toxic Element Concentration in Fruits Collected from Markazi Province(Iran): A Probabilistic Health Risk Assessment

Objective This study was conducted to evaluate the concentration of potentially toxic elements(PTEs)such as arsenic(As),cadmium(Cd),mercury(Hg),and lead(Pb)in fruit samples collected from Markazi Province,Iran.A probabilistic health risk assessment due to ingestion of PTEs through the consumption of these fruits was also conducted.Methods The concentration of PTEs in 90 samples of five types of fruits(n=3)collected from six geographic regions in Markazi Province was measured.The potential health risk was evaluated using a Monte Carlo simulation model.Results A significant difference was observed in the concentration of PTEs between fruits as well as soil and water samples collected from different regions in Markazi Province.The order of PTE concentration in the soil and water samples was as follows:Pb>As>Hg>Cd.Furthermore,the highest level of transfer factor for Cd and Hg correlated with the grape.The estimated daily intake for adults and children was lower than the recommended tolerable daily intake.Conclusion The population in Markazi Province,Iran,is not at considerable noncarcinogenic or carcinogenic risk due to the ingestion of PTEs through the consumption of the examined fruits.

数据要素市场化推进力评价指标体系构建研究

[目的/意义]构建数据要素市场化推进力评价指标,旨在发现数据要素市场发展的关键因素与策略,推动数据要素理论与实践的发展。[研究设计/方法]通过文本分析、专家咨询等方法,对数据要素市场化推进力评价指标体系予以构建。[结论/发现]形成了以基础环境、保障支撑和执行推进为三大维度的细化至33项四级指标的评估指标体系,并立足我国实际展开应用与验证,随后就指标体系的优化提出展望。[创新/价值]从政府主导的数据要素市场化推进的视角构建评价指标体系,并融入信息资源管理的学科基础理论与方法。

不同供磷水平对椰枣幼苗生长、生理指标和营养元素含量的影响

【目的】通过分析不同供磷水平对椰枣幼苗生长、生理指标和营养元素含量的影响,为构建椰枣幼苗平衡施肥技术提供理论依据。【方法】以椰枣幼苗为试验材料,采用盆栽试验,设4个供磷水平处理,浓度分别为5(CK)、100、1000和5000μmol/L,培养7个月后,观察测定幼苗的生长、生理指标和营养元素含量。【结果】5μmol/L供磷水平下,椰枣幼苗长势弱;100μmol/L供磷水平下椰枣幼苗的根部鲜重显著低于1000μmol/L供磷水平(P<0.05,下同);1000μmol/L供磷水平下椰枣幼苗长势好,其根部鲜重、地上部干重、株高增加量、植株磷含量、植株磷累积量、第3叶和第6叶片中的可溶性蛋白含量均显著大于CK;5000μmol/L供磷水平下,新抽叶片密集,根部磷利用效率和植株磷利用效率最低。同一供磷水平下,椰枣幼苗茎尖中的磷含量高于叶片和根尖。不同供磷水平对地上部和根部氮、钾、钙、镁、钠、铝元素的含量影响不同。随着供磷水平的增加,地上部和根部的钾、铝含量,以及地上部钙含量均先增加后降低,地上部镁含量逐渐增加,根部钙、镁含量逐渐降低;5000μmol/L供磷水平下,地上部和根部的钠含量达最高。1000μmol/L供磷水平下,椰枣幼苗地上部的氮、钾、镁、钠、铝的累积量,地上部氮利用效率,以及地上部和根部的钙利用效率显著大于CK。【结论】营养液中的供磷水平会影响椰枣幼苗的长势、生理指标及营养元素的含量、累积量和利用效率。过低或者过高供磷水平均不利于椰枣幼苗的生长,1000μmol/L供磷水平下,椰枣幼苗长势良好。

数据要素市场化推进:进展、问题与对策

[目的/意义]系统地总结当前全国各地的数据要素市场化推进的实践进展及经验做法,为政策制定和实践工作提供参考,为相关领域的研究提供实证基础。[研究设计/方法]基于数据要素市场化推进力的评价指标体系,从基础环境、保障支撑、执行推进三个维度,对31个省(自治区、直辖市)的推进情况展开深入调查和综合分析。[结论/发现]我国数据要素市场化推进整体上呈三级梯队分布并呈现出显著的地域特征。各地在产业环境发展、制度保障、技术平台建设、公共数据开放与授权应用、数据流通交易方面取得了积极成效,但也存在着区域发展不平衡、公共数据制度体系不完善、场内数据交易规模不足等问题。基于此从区域间产业协调发展、制度保障体系建设和加强公共数据供给激活数据流通三个方面提出了政策建议。[创新/价值]对全国数据要素市场化推进进行了全景式的调查和研究,提炼共性问题,总结发展经验,为推动数据要素市场化向纵深发展提供借鉴。

中文文献地理元素标引的实践与思考

提高书目数据质量,规范文献主题标引,是中文文献信息组织与资源建设的基础环节。编目实践中有关中文文献地理主题的标引工作失序。地理学严密而系统的学科体系为精准揭示和深度标引地理元素提供了较为广阔的视角。结合对主题词表的分析研判以及对主题标引工作经验的提炼总结,明确地理标引的客观性、专指性、简洁性及实用性4项标引原则,结构化地理标引的基本步骤,规范化地理标引的常规做法。最后,从优化标引系统与编目工具、完善地理分类主题的逻辑体系、提升编目标引工作的管理效度等方面提出改进标引工作的措施。

基于振动速度与噪音的横梁动态特性优化

针对某型小五轴高精密数控机床加工精度不高的问题,对其横梁的动态性能进行研究.采用锤击模态测试实验与有限元模拟计算相结合的方法,对横梁的固有频率进行研究;测量主轴不同转速下的振动速度和振动噪音,通过赋权处理,建立振动评价指标方程,得到优化目标;对所研究横梁进行形状优化.试验与仿真所得固有频率最大误差为5.76%;基于主轴振动情况确定83~117 Hz的频率范围,作为横梁设计时需要避开的低阶固有频率范围.经过形状优化后,横梁的一阶固有频率为139 Hz,相较于原横梁增加了约20.870%,横梁的动态性能得到改善.

Analysis and Design of a 3 dB Tunable Lumped-Element Directional Coupler

An analysis of a 3 dB lumped-element directional coupler （LEDC） based on arbitrary terminal impedance is described numerically. To solve the conflicted requirement for broad bandwidth and small size in LEDC, a new structure of coupler is introduced, which can significantly improve bandwidth and whose size is only 3 cm×4 cm on the conditions of the frequency domain of 410 MHz to 490 MHz. The measure results are in good agreement with simulations despite the unexpected resistor loss.

AN APPROACH TO SOME PROBLEMS OF TECHNOLOGICALMINERALOGY STUDY ON THE ORE OFASSOCIATED GAIN ELEMENT

In this paper we put forward a new concept——the ore of associated gain element. It is thought that the theoretical index forecast of dressing and smelting should be the component part of contents of technological mineralogy study. The relative problems of the representativeness of ore sample, the handling of study sample and the choice of test means, and the examination of element existance form in the ore, etc., are discussed.