Effect of H_2 dilution on the structure and properties of nc-CrC/a-C:H coatings deposited by a hybrid beams system

Nanocomposite Cr C/hydrogenated amorphous carbon(nc-CrC/a-C:H) coatings were deposited by a hybrid beams system comprised of a hollow cathode ion source and a cathodic arc ion-plating unit with varying H_2 flow rates. The influences of H_2 flow rates on the morphologies, microstructures, and properties of the coatings were systematically studied. The morphologies and microstructures of the coatings were characterized by SEM, AFM, XPS, Raman spectroscopy, GIXRD, and HRTEM. The mechanical and tribological properties were measured by a nano-indenter, scratch tester, and ball-ondisk tribometer. The wear tracks were evaluated using 3D profilometer, optical microscope, and EDS analysis. It has been found that a moderate H_2 flow rate can effectively smooth the surface, enlarge the fraction of a sp~3 bond, and improve the properties. The coating exhibits the highest hardness and elastic modulus at the H_2 flow rate of 40 sccm. A superior combination of adhesion strength,friction coefficient, and wear resistance can be achieved at the H_2 flow rate of 80 sccm.     

DHDECMP-TBP/煤油萃取 HNO_3-稀土过程中防止形成第二有机相的研究

研究了ＤＨＤＥＣＭＰ－ＴＢＰ／煤油萃取ＨＮＯ３后形成和防止形成第二有机相的各影响因素。以Ｇｄ代表稀土，探讨了ＤＨＤＥＣＭＰ－ＴＢＰ／煤油萃取稀土时ＤＨＤＥＣＭＰ浓度、ＴＢＰ浓度、水相ＨＮＯ３浓度和温度对有机相萃取负载量的影响。结果表明：０．６０ｍｏｌ／ＬＤＨＤＥＣＭＰ－１．４０ｍｏｌ／ＬＴＢＰ／煤油能有效避免第二有机相的形成，又能满足工艺负载量的要求。     

锶-90同位素放射源屏蔽结构设计

在~(90)Sr放射源结构设计基础上,利用Monte Carlo程序MCNPX计算~(90)SrTiO_3陶瓷源表面的轫致辐射能谱和放射源外空间的剂量当量分布情况,并计算和设计屏蔽层。结果表明,90SrTiO_3陶瓷放射源表面的平均光子通量率约1.2×10~(10)cm~(-2)·s~(-1),表面最小剂量当量率约20Sv/h;应用厚度为7cm的钨材料屏蔽后,表面和1m处最大剂量当量率分别约为1.35mSv/h和0.027mSv/h,满足放射源运输要求。     

Nitrogen utilization and transformation in red soil fertilized with urea and ryegrass

The influence of fertilization with urea and ryegrass on nitrogen utilization and transformation in red soil has been studied by using ^15N tracer method.When urea and ryegrass were applied alone or in combination,the percentage of N uptaken by ryegrass from labelled urea was 3 and 1.7 times that from labelled ryegrass for the application rate of 200mgN.kg^-1 and 100mgN.kg^-1,respectively;combining application of ryegrass and ureareduced uptake of urea N and increased uptake of ryegrass N by ryegrass plant,but the percentage of N residued in soil increased for urea and decreased for ryegrass.when urea and ryegrass were applied alone,the percentage of N residued in soil from labelled ryegrass was more than 69% while that from labelled urea was less than 25%,and much more ryegrass N was incorporated into humus than urea N.     

涡流灶使宝鸡市民乐在其中

翻看 2000年 10月份的宝鸡日报《西部周末》,“宝鸡供电局优质服务全面提速”的服务承诺和措施跃然纸上。“一切始于客户需要,一切终于客户满意”的宣传语格外醒目。在整版的服务公示内容中,“涡流灶试用一月”的条款特别吸引人：凡已实行一户一表供电的客户（家庭）,可在华通商厦宝鸡供电局电热电器演示厅借用涡流灶一台,试用一个月,满意者可交钱购买,不满意者原物退回。百闻不如一见,记者趁中午时分,立即驱车赶往华通商厦。 华通商厦位于宝鸡火车站附近,是该市大型百货商场之一。虽在 12月初的隆冬季节,其周围仍车水马龙,行…     

小波瀑布型多重网格法

为了提高偏微分方程的计算精度,由瀑布型多重网格的速度收敛快以及小波多分辨分析的性质,通过改进传统瀑布型多重网格算法中的插值算子,提出一种新的小波瀑布型多重网格方法。数值结果表明,小波瀑布型多重网格方法比传统的瀑布型多重网格方法具有更高精度。     

超重力强化分离铜渣中铜的数值模拟及辅助工业设计

由于当前铜冶炼工艺产生的铜渣铜含量比较高,采用传统的电炉贫化技术分离铜液滴时间长、回收率低,因此引入超重力技术对贫化过程进行改善。采用数值模拟的方法,以卧式离心机为模型基础,选用转炉铜渣作为试验对象进行研究,借助COMSOL Multiphysics软件构建模型,模拟铜渣中铜液滴的沉降过程。根据计算结果分析重力系数（G）、温度（T）对不同粒径铜液滴沉降行为的影响。结果表明,在T=1 300 ℃、G=1的条件下,粒径低于80 μm的铜液滴无法自由沉降;在恒定温度下,重力系数以及铜液滴粒径的增加均有利于铜液滴在铜渣中的沉降;温度升高会降低铜渣和铜的黏度,促进二者分离。最后,根据铜液滴的沉降数据,对离心机半径、给料速度等工业参数提出优化建议,以提升铜的回收率,降低企业生产成本。     

321不锈钢工艺控制及成品板缺陷形成机理研究

介绍了某钢厂炉卷轧机生产321不锈钢的化学成分设计、生产工艺控制和成品板的力学性能,并利用光学显微镜、扫描电镜对生产的321不锈钢夹杂物形貌及成品板表面缺陷进行了观察与分析。结果表明:炉卷轧机生产的321不锈钢力学性能优良,表面质量较好,其主要的表面缺陷为线鳞,是由于连铸坯中TiN夹杂物大量聚集造成的。控制影响夹杂物产生的Ti、Al、N、O等元素含量,设置合理的LF炉吹氩搅拌参数,控制浇注时的过热度等措施可有效改善321不锈钢成品板的表面质量。     

Change in Carbon Dioxide （CO2） Emissions From Energy Use in China＇s Iron and Steel Industry

 As the largest energy consuming manufacturing sector and one of the most important sources of carbon dioxide (CO2) emissions, the China′s iron and steel industry has paid attention to the study of changing trend and influencing factors of CO2 emissions from energy use. The logarithmic mean Divisia index (LMDI) technique is used to decompose total change in CO2 emissions into four factors: emission factor effect, energy structure effect, energy consumption effect, and steel production effect. The results show that the steel production effect is the major factor which is responsible for the rise in CO2 emissions; whereas the energy consumption effect contributes most to the reduction in CO2 emissions. And the emission factor effect makes a weak negative contribution to the increase of CO2 emissions. To find out the detailed relationship between change in energy consumption or steel production and change in CO2 emissions, the correlation equations are also proposed.     

轧钢生产质量信息在质量管理工作中的应用

运用计算机网络和数据库管理系统,对国晟品打关数据进行采集,分析和处理,并自动为质量管理部门形成所需的报瑶和质量证明书,达到了提高工作效率和管理水平的目的。