直线感应加速器机械轴精密对中方法

 介绍了大型直线感应加速器机械轴精密对中安装方法和工艺。直线感应加速器由多个组元连接而成，总长几十m。采用激光跟踪仪并配以全站仪、水准仪进行准直测量，再用专门设计的高精度调节机构调节，可使机械轴的准直达到较高的精度。分析了准直安装各步骤能达到的精度，研究了几十m长机械轴准直控制测量网的建立和理论坐标值的修正。     

Degeneracy graphs: theory and application an updated survey

A survey of various aspects of the theory and application of degeneracy graphs (DGs for short) is given. The notion and some basic properties of DGs are introduced, cycling of the simplex method is discussed, the neighborhood problem is tackled, and the application of the so-called optimum DGs to particular problems which are connected with optimal degenerate solutions of a linear programming problem is presented. The impact of weakly redundant constraints on various postoptimal analyses under degeneracy is briefly described.     

International Perspective on Government Nanotechnology Funding in 2005

The worldwide investment in nanotechnology research and development (R&D) reported by national government organizations and EC has increased approximately 9-fold in the last 8 years – from $432 million in 1997 to about $4,100 million in 2005. The proportion of national government investments for: academic R&D and education are between 20% (Korea, Taiwan) and 65% (US), industrial R&D – between 5% (US) and 60% (Korea, Taiwan), and core facilities and government laboratories – about 20–25% in all major contributing economies. This evaluation uses the NNI definition of nanotechnology (that excludes MEMS or microelectronics), and is based on direct information and analysis with managers of nanotechnology R&D programs in the respective countries.     

On the Geometry of the Saccharinato Ligand/Ion in the Metal Saccharinates: Crystallographic Survey and Theoretical Study

The structural data for the five-membered ring of unsubstituted saccharinato ligands/ions in saccharinates are retrieved from the Cambridge Structural Database and analyzed. The average geometries of saccharin and the corresponding deprotonated species in the solid state are obtained and the extreme cases of highly distorted structures are pointed out. The influence of the nature of the metal ion as well as of the type of the metal-to-saccharinato bonding on the saccharinato geometry is examined. On going from saccharin or covalent saccharinates to ionic ones the bonds adjacent to the nitranionic center are shortened, while the carbonyl and sulfonyl groups are simultaneously stretched. The value of the internal angle at the nitrogen atom is lowered and that at the sulfur atom is increased, causing bending of the angle between the sulfonyl oxygen atoms. The average geometries are reproduced well by several (semiempirical and ab initio) theoretical models.     

The view of laboratories’ clients on the value of accreditation

The Swedish National Testing and Research Institute (SP) asked its clients in its 2001–2002 customer satisfaction survey how they valued an accredited test result on a scale of 1-6. As many as 81% of the recipients answered that it was important (a score of 5 or 6 on the scale ) to have an accredited test result. 12% found the question irrelevant, which could be interpreted as that they used some of SPs non-accredited services, or were just not interested in accredited test reports.     

宁波天童森林公园两栖爬行动物初步调查

在1994～2000年间记录了天童森林公园活动的两栖动物15种,隶属2目6科,爬行动物30种,隶属3目8科.两栖动物东洋界种占80.0%,古北界种占20.0%;爬行动物东洋界种占76.7%,古北界东洋界广布种占23.3%,具有南北过渡特征,并对其区系成分进行了分析.     

Some more space‐group corrections

A survey of approximately 100 000 entries in recent releases of the Cambridge Structural Database (CSD) has uncovered 156 crystal structures that were apparently described in inappropriate space groups. We have revised these space groups and prepared CIFs containing the new coordinates and brief comments describing the revisions.     

A list of organometallic kryptoracemates

The vast majority of racemic solutions of chiral compounds apparently crystallize at room temperature in non‐Sohncke space groups as racemic crystals. However, kryptoracemic crystals composed of nearly enantiomeric pairs occasionally crystallize at room temperature, or appear as low‐temperature phases, in Sohncke space groups. As a complement to the previously published catalog of organic kryptoracemates [Fábián & Brock (2010). Acta Cryst. B 66 , 94–103], 1412 chiral organometallic crystal structures have now been extracted from the Cambridge Structural Database and analyzed. 26 are listed herein as credible kryptoracemates. The possible influence of temperature is discussed, together with some problems in characterizing and classifying these structures.     

船用惯性系统试验安装标校与变形测量

船用惯性系统试验安装标校和变形测量是提高测量精度,保证试验质量的关键技术,因此在对设备的安装误差和船体变形造成的测量误差进行分析的基础上,重点阐述惯性系统试验零位对准和变形测量的相关理论和工程技术。     

动态约束下的惯性姿态测量系统分析

分析了动态条件下，载体姿态参数的惯性测量问题。以实际工程应用为背景，推导了运动约束条件下，基于两个激光陀螺，两个加速度计的系统姿态测量模型。根据载体姿态动态变化的不同频谱特性，进行了基于频域分析的算法设计，通过实验验证了算法的可行性。