镍基高温合金脱氮工艺的研究

研究了真空感应熔炼镍基高温合金过程中的脱氮工艺并初步分析了镍基高温合金中钛对氮的相互作用,近似地计算出其相互作用系数.在现有的条件下,本研究的目的是获得实验数据以此来分析氮的含量并计算出钛对氮的相互作用系数,从而确定最佳的脱氮工艺.     

外加碳源对SBR法处理啤酒废水的影响

本试验以啤酒废水为试验对象，通过投加不同种类及不同浓度的外加碳源来研究其对SBR法脱氮除磷效果的影响。试验结果表明外加碳源能大大提高SBR法对氮、磷的去除率。而且啤酒废水与甲醇和葡萄糖相比可使总氮去除率稳定提高，对总磷也有最佳的去除效果。同时啤酒废水来源广泛、价格低廉，因此是外加碳源的最佳选择。     

镍基高温合金中钛对氮相互作用系数e_N~(Ti)和活度系数f_N的计算

研究了Ni/N/Ti系合金的真空感应熔炼过程,通过分析氮含量的变化,计算了镍基高温合金中钛对氮的相互作用系数值为-0.38,氮的活度系数为0.174,氮的溶解度为0.0003%。     

切割线用钢的真空感应熔炼工艺试验

为防止拉拔过程断丝,割线用钢要求对其材料中的夹杂物、残余铝含量和氧含量严格控制,通过试验,文中提供了一种高碳低铝低氧的切割线用钢的真空感应熔炼工艺,使用有氧化铝材质坩埚的真空感应熔炼炉进行熔炼,通过工艺中的设备参数、原材料控制、加料顺序、不同熔炼阶段的温度控制和炉内氛围控制等措施,熔炼浇铸后钢中铝含量和氧含量达到国外进口产品水平,氮含量则明显低于国外同类进口产品。     

一种新牌号Ni基高温合金的超纯净熔炼

研究了在真空感应炉中采用CaO坩埚熔炼一种新牌号Ni基高温合金的效果，结果表明，采用CaO坩蜗熔炼，当熔化期为25min时，O，N的脱除率分别为52％和5％，加入适量的C有利于O，N的去除，加入02％C比没加C时O，N可分别多脱除36％和60％，高温高真空下单纯使用CaO坩埚而无碱性渣不能脱S，加入0．5％Al后经．50min精炼可脱除35％的S。     

真空炼钢条件下的脱气动力学计算

通过数学物理模型的建立，采用数值计算法，计算了真空炼钢条件下，通过产生的ＣＯ气泡脱氮的动力学规律，找出了不同深度产生的ＣＯ气泡脱氮的不平衡参数和脱氮数量与熔池深度的关系。     

A/O脱氮工艺中外碳源投加控制器的建立与研究

反硝化需要以有机碳源为电子供体,当污水厂进水COD／TN较低时将会抑制反硝化反应的顺利进行,为了提高脱氮效率,需外投碳源。为了有效控制外碳源投加量,本文根据活性污泥数学模型建立了外碳源投加前馈—反馈控制器,确定维持缺氧区末端硝酸氮浓度为1mg／L时,能实现以尽可能少的外碳源投量大大降低出水硝酸氮和总氮浓度的目的。模拟表明该控制器抗冲击负荷能力强,响应快,易于在线控制,可显著提高污水厂脱氮效率。     

钒合金真空精炼过程杂质元素去除研究

核能用钒合金要求纯净度极高,一般都要进行真空熔炼去杂质,但目前对钒合金真空熔炼去杂质的条件和机制还不很清楚。为此,本文对钒合金真空熔炼过程杂质元素的去除机制和热力学条件进行了较全面的理论计算和实验数据对比分析,结果表明:钒合金真空熔炼过程中,Al、Fe、Cr、Cu、Ni、Si、Ca、Ti等金属杂质元素都能以金属蒸汽的形式挥发去除;合金中的氧能够以碳氧化物或低价金属氧化物VO(g)、AlO(g)、Al_2O(g)、TiO(g)、SiO(g))形式除去;合金中氢的除去效果也比较好,但合金中的氮则基本不能通过真空熔炼除去。     

城市污水脱氮除磷生物处理技术

本文系统地概述了城市污水脱氮除磷的机理,介绍了脱氮除磷的生物处理方法,并重点分析了城市污水生物脱氮除磷的成熟工艺及近几年的新工艺,同时对今后生物脱氮除磷技术的发展进行了展望。     

浅谈脱氮新工艺

传统的生物脱氮工艺存在着工艺流程长,脱氮效率低,占地大,成本高等缺点。随着新型脱氮技术的不断发展,突破了传统脱氮工艺的局限,涌现了一批新型脱氮工艺。本文综述短程硝化(SND),厌氧氨氧化(ANAMMOX),好氧反硝化(aerobic denitrification)等目前热点研究的脱氮新工艺,阐述了脱氮原理,影响因素,工艺特点,并与传统脱氮工艺进行对比。     

Insertion of triangulated surfaces into a meccano tetrahedral discretization by means of mesh refinement and optimization procedures

In this paper, we present a new method for inserting several triangulated surfaces into an existing tetrahedral mesh generated by the meccano method. The result is a conformal mesh where each inserted surface is approximated by a set of faces of the final tetrahedral mesh. First, the tetrahedral mesh is refined around the inserted surfaces to capture their geometric features. Second, each immersed surface is approximated by a set of faces from the tetrahedral mesh. Third, following a novel approach, the nodes of the approximated surfaces are mapped to the corresponding immersed surface. Fourth, we untangle and smooth the mesh by optimizing a regularized shape distortion measure for tetrahedral elements in which we move all the nodes of the mesh, restricting the movement of the edge and surface nodes along the corresponding entity they belong to. The refining process allows approximating the immersed surface for any initial meccano tetrahedral mesh. Moreover, the proposed projection method avoids computational expensive geometric projections. Finally, the applied simultaneous untangling and smoothing process delivers a high‐quality mesh and ensures that the immersed surfaces are interpolated. Several examples are presented to assess the properties of the proposed method.     

Certification Institutions Expected to Update and Transfer Information on Present Standards

Standards are the basis for production enterprises to organize production, ex-factory inspection, trade (delivery) and technical exchanges, product certification, quality arbitration and supervision.……     

Flow calorimeter for enthalpy increment measurements on condensed gases

A flow calorimeter for enthalpy increment measurements on condensed gases is presented. A better knowledge of the properties of the liquefied natural gas is needed, and therefore a liquid loop has been designed for our flow calorimeter. The fluid loop in the calorimeter is designed in order to avoid the two-phase region, since two phases would give compositional disturbances in the measurements. The avoidance of the two-phase region is made possible by increasing the pressure of the test fluid after the measurement section, then heating the fluid at super-critical pressure past the critical point. Finally, the fluid is throttled to the low-pressure gas state at the inlet condition of the compressor that circulates the fluid. To perform the pressure increase, a new cryogenic pump has been designed. To evaluate the new equipment, measurements were taken on liquid ethane over the temperature range 146–256 K at pressure between 0.9 and 5.1 MPa.     

Refrigerators Enter a New Era of Health Preservation Frestech initiates the establishment of China's first standard for household sterilization refrigerators

On November 30, 2007, the China Association for Standardization (CAS) held a press conference at Beijing Diaoyutai State Guest House. Leaders from the China Household Electric Appliance Research Institute, the China Household Electric Appliance Association, and the China Consumers' Association attended and made speeches.……     

Optimum-Simulation von Ernteprozessen

Zusammenfassung Bei der Gestaltung von Ernteprozessen — beispielsweise des Prozesses Mähdrusch, Körnertransport und -abnahme — als transportverbundene Fließarbeitsverfahren mit mindestens zwei verschiedenen Arbeitsmitteln gibt es einen großen Optimierungsspielraum. Solche Prozesse sind mehrstufige Bedienungsprozesse mit gemischter Anordnung der Bedienungseinrichtungen. Außerdem besitzen sie stark ausgeprägte räumliche Aspekte. Es wird vor allem gezeigt, welche Merkmale solcher Prozesse in Simulationsmodellen abgebildet sein müssen, welche Zielgrößen in Abhängigkeit von welchen Einflußgrößen unter Berücksichtigung welcher Prozeßbedingungen ermittelt werden sollten und wie der Bewertungsprozeß zur Ermittlung der gewünschten Informationen gestaltet werden muß.     

A study of centrifugal cast high boron high speed steel

In the present study a high‐boron high speed steel (HSS) roll material was designed. Many expensive alloy elements have been substituted by cheap boron alloy, and high‐boron high speed steel roll has been manufactured by centrifugal casting method. The microstructures, mechanical properties and wear resistance of centrifugal casting high‐boron high speed steel roll have been investigated by optical microscopy (OM), scanning electron microscopy (SEM), and X‐ray diffraction (XRD) analysis, hardness test, impact test and wear test. The results indicated that the solidification microstructures of high‐boron high speed steel roll consisted of M₂(B,C), (W,Mo)₂(B,C), M₃(B,C), M₂₃(B,C)₆ type borocarbides and martensite, a small amount of retained austenite. Borocarbides were continuously distributed over the grain boundary. After quenching from 1050 °C, local broken network appeared in partial borocarbides, and fine secondary borocarbide precipitated from the matrix. After tempering from 525 °C, the amount of precipitated borocarbide increased significantly. After heat treatment, the hardness of high‐boron high speed steel roll excelled 60 HRC, and its impact toughness excelled 8.0 J/cm². The single groove steel rolling amount of high‐boron high speed steel rolls increases by 500% than that of bainite cast iron roll, when the rolls are used in K₁ mill housing of bar mill.     

Brainstorming for ISO Strategy 2016-2020

正Responding to ISO’s appeal for survey for the to-be-developed ISO Strategy Plan for 2016-2020,SAC hosted a special workshop over the needs and comments of various fi elds on June 8 in Beijing.The workshop was attended by ISO President-elect and Ansteel General Manager Zhang Xiaogang,SAC Vice-Administrator Yu Xinli,and 30 experts from     

CNAS Passes APLAC's PTP Review

正The review group of Asia Pacific Laboratory Accreditation Cooperation(APLAC)carried out a 4-day peer review of the proficiency testing provider(PTP)for China National Accreditation Service for Conformity Assessment(CNAS)from July 28 to 31,2014.CNAS passed the PTP review with excellent performance.Two senior peer reviewers of APLAC made a comprehensive,rigorous and detailed review of CNAS’s PTP accreditation activities,and made the on-spot inspection of the review groups in Shanghai and Shenzhen respectively.     

新闻(英文)

正China and Greece Sign the Standardization Cooperation Agreement Witnessed by Chinese Premier Li Keqiang and Greek Prime Minister Antonis Samaras,AQSIQ Minister Zhi Shuping and ELOT Chairman and Executive Director Angelos Tolkas signed the SAC-ELOT Standardization Cooperation Agreement.The Agreement is one of the critical cooperation documents signed during Li Keqiang’s visit in Greece,encouraging China and Greece to