工业污泥用于根瘤菌菌剂生产的新方法

接种根瘤菌技术在农业生产中应用广泛。根瘤菌菌剂的生产涉及两大因素：根瘤菌生长培养基和用于固体菌剂生产的载体。最近,全世界一种广泛存在的可再生废料——污水污泥正被研究用作接种根瘤菌剂生产的培养基和载体。研究表明,污泥通常含有足以维持根瘤菌生长的氮元素,其重金属含量也较低。并且可以通过污泥预处理或者添加营养素的方法优化其生长条件。同普通菌剂相比,污水污泥中生长的根瘤菌能够使植物进行有效的结瘤和固氮。这种接种根瘤菌剂生产的新方法为废料处理和菌剂生产提供了一种安全、经济、环保的选择。     

Time averaged temperature calculations in pulse electrochemical machining, spectral approach

Simulation of the temperature distribution during the Pulse Electrochemical Machining (PECM) process provides information on system design and guidelines for practical use. The pulses that are applied to the PECM system have to be described on a time scale that can be orders of magnitude smaller than the time scale on which the thermal effects evolve. If the full detail of the applied pulses has to be taken into account, the time accurate calculation of the temperature distribution in PECM can become a computationally very expensive procedure. A different approach is used by time averaging the heat sources of the system. Performing this, the time steps used during the calculations are no longer dictated by the pulse characteristics. Using this approach, computationally very cheap, yet satisfying results can be obtained. In previous work of the authors, the hybrid calculation and the Quasi Steady State ShortCut (QSSSC) were introduced. This method allows to perform simplified calculations while getting satisfactory results. The method introduces errors however, which were quantified using analytical solutions and found to be acceptable. The results applied only to rectangular pulses. In this work, the more general case of arbitrary pulse forms is considered using a spectral approach.     

Processing of carbon-fiber reinforced (SiC + ZrC) mini-composites by soft-solution approach and their characterization

Carbon-fiber reinforced (SiC + ZrC) mini-composites have been prepared via soft-solution process using inorganic precursors. In this process, water-soluble compounds have been used to act as precursor materials to impregnate the fiber tow. Thermal analysis provided the temperature range for the pyrolysis to convert the precursors into the desired (SiC + ZrC) matrix. X-ray diffraction of the composites confirmed the phase formation and the crystallite size of these phases were in the range of 25–40 nm. Cross-sectional microstructures of the composites have shown the matrix formation around each individual fiber. The mechanical properties revealed that the tensile strength and fracture energy of the composites pyrolyzed at 1600 °C were significantly higher with typical composite failure behavior, as compared to those pyrolyzed at 1700 °C. The statistical size effects of the tensile strength were investigated on the basis of the Weibull statistics.     

钢筋保护层施工方法的探讨

在实际的钢筋混凝土施工中,钢筋保护层厚度控制常常被忽略,原因有多种。常规做法是现场制作等同保护层厚度的水泥块,在进行钢筋绑扎时。垫在钢筋下面,以控制钢筋保护层厚度。但这种做法的最大弊病就是在后续施工过程中常常被压碎或难以被控制在原位置,从而在混凝土施工过程中无法对钢筋的保护层进行有效的控制。而在施工现场利用大量的钢筋短头进行钢筋保护层控制,从而可解决这一问题。     

高校绿色建筑实现途径的探讨

文章根据《绿色建筑评价标准》,结合高校校园建设实际情况,对绿色校园建设可实现的途径进行了探讨,提出了可行的方案。     

地铁车站主要施工工法比较与浅析

根据地铁车站的功能、所处的周边环境和水文地质条件、施工的难易程度以及施工期间对交通和居民生活的影响等因素,介绍了在地铁车站施工中经常采用的几种主要施工工法。并对这些工法进行了比较,分析了这些工法的各自适用条件和优缺点。     

An ontology-based approach for formalisation and semantic organisation of conformance requirements in construction

This paper presents an ontology-based method for the formalisation and application of construction conformance requirements for effective code checking. This research continues our work on the development of a generic model automating the conformance checking of construction projects against building codes. We start from the analysis of the related research on the formalisation and organisation of building codes that allows us to formulate our approach for semantic annotation and scheduling of conformance requirements for conformance checking task. Our approach comprises 5 main steps: formalisation, semantic annotation, classification, context-based scheduling and semantic search of conformance requirements. They are implemented as corresponding key components of the C3R (Conformance Checking in Construction — Reasoning) prototype that we have developed to model the conformance checking process in construction. Finally, we discuss the ongoing work and perspectives of our research: the validation of our model by construction practices and the enrichment of our approach by usage-based knowledge.     

中美两高校物理化学课程教学的对比

物理化学课程是化学、化工、生物工程、环境工程、材料工程等专业的一门重要的专业基础课。为了适应社会发展的需要,物理化学课程教学的改革势在必行。笔者观摩了美国田纳西大学物理化学教学的全过程,受到了一些深刻的启示和借鉴,认为借鉴美国高校物理化学教学的先进经验,将以教师为中心的教学模式转变为以学生为中心的教学模式,是提高物理化学教学效果的一个有效途径。     

信号交叉口公交专用进口道设置方法的探讨

在信号交叉口设置公交专用进口道可减少公交车辆在信号交叉口的停车延误,是实施公交优先的有效技术措施之一。近年来,为体现公交优先,我国少数大城市的一些信号交叉口设置了公交专用进口道,但一些公交专用进口道的设置还不尽合理。为此,分别按直行、左转、右转公交专用进口道来分析各自设置方法,并对公交专用进口道的设置条件和设置长度进行了分析。     

Networked Space

Dennis Shelden , Chief Technology Officer at Gehry Technologies, asserts ‘a networked spatial approach to design informatics’ that brings together a spatial understanding with a current knowledge of geometry, the digital and modern communications. This emphasises the connections between not only forms and objects in space, but also among disciplines in a collaborative practice context and of the Web itself. It is a connectedness that has been further facilitated by the adoption of 3-D building information modelling (BIM) that helps to streamline processes and facilitate better communication among disparate members of the design team.