基于Pro/E的设计与工艺信息共享关键技术研究

阐述了利用Visual C＋＋6．0、Pro／Toolkit和数据库的强大功能从设计信息中提取相关的零部件信息及将工艺信息输出到绘图环境下的具体方法和过程，实现了在Pro／E环境下设计与工艺之间的信息共享、无缝连接，并给出了实例。     

The internal-nitriding behavior of 310 stainless steel with and without Al and Ti additions

The internal-nitriding behavior in ammonia-hydrogen atmospheres of type-310 stainless steel and 310 to which either 2 wt.% Ti or 3 wt.% Al were added was studied over the range of 550–950°C. An Fe-24Cr binary alloy was included to assess the role of a BCC crystal structure vs the FCC crystal structure of 310 stainless steel. The BCC alloy exhibited the most rapid kinetics as expected. X-ray diffraction showed only the presence of CrN in all the alloys up to 735°C. At 850°C and above, both CrN and Cr₂N were detected. The nonformation of TiN and AlN at lower temperatures is attributed to nucleation problems. Precipitates were extremely fine (unresolvable even at 20,000×) at 563°C and became much coarser with increasing temperature. The precipitate density, size, and shape varied across the internal-nitriding zone at the higher temperatures. External scaling was noted at 850°C and above, however, it was not a continuous film. The activation energy of internal nitriding from 563–735°C ranged from 3.8 kcal/mol for 310+2Ti to 18.2 kcal/mol for 310+3Al; from 850–950°C, the activation energy ranged from 44 (310+2Ti) to 56.6 kcal/mol (310+3Al). Microhardness profiles show that an intermediate zone exists between the nitride case and the base metal. The origin of this zone is discussed.     

Pro/E工程剖视图与制图国标不相符合问题的解决方法

利用Pro/E三维模型与二维图形双向关联功能可以快速生成工程图,但由于在视图表达上有些方面不符合我国制图标准而影响其有效使用.本文针对Pro/E制作工程剖视图时所存在的与制图国标不相符合的问题,提出了解决这些问题的方法和技巧.     

The establishment of the statistical-thermodynamic model of D81-structure and its application to α-Nb5Si3

A statistical-thermodynamic model for binary nonstoichiometric A₅B₃ with D8₁-structure has been established on the basis of the grand canonical ensemble. In the model the average chemical potentials according to the composition and a new extra equation as a boundary condition are proposed for more accuracy and free experimental data calculations. The model can be used in any A₅B₃ type compounds with D8₁ structure. The establishment method of the statistical-thermodynamic model can be extended to other complicated structures. We apply the statistical-thermodynamic model to α-Nb₅Si₃ and the parameters used in the model are obtained from the first-principles' calculations. From these parameters the expression for the point defect concentrations as a function of compositions and temperatures is obtained by numeral calculations. The constitutional defects and thermal defects in α-Nb₅Si₃ are discussed.     

一种用于数控车削几何仿真的算法

利用开放式三维图形程序标准OpenGL函数库及CAD\CAM软件Pro／E，建立具有真实感的虚拟加工环境，通过对被加工零件离散化，将毛坯表面离散成三角形网格，实现数控车削加工过程的实时仿真。     

The role of isotopic techniques on the evaluation of the agronomic effectiveness of P fertilizers

Many isotopic techniques can be applied to determine the relative immediate and residual effectiveness of P fertilizers. Using isotopes as tracers, the percentage of utilization by plants of the P derived from a fertilizer can be determined. However this is only possible during the three or four months after the application. Therefore, the P fertilizers may be classified only according to their relative immediate effectiveness. To also evaluate residual effect, which can be observed when more P is applied than is removed with harvest, isotopes of phosphorus can be used. This residual effect is determined by comparing pool sizes of bioavailable soil P in soils with and without P fertilizer aged in soil. The bioavailable soil P pool may be analyzed according to three isotopic experimental procedures which give access to either the A value, or the E value or the L value. The aims, the similarities and the differences between these three procedures, are examined. Some of the theoretical and practical constraints of each method are described in this paper; they must be followed in order to obtain reliable information for agronomic purposes. A method involves measuring the rate of isotopic exchange of phosphate ions in soil-solution systems maintained in steady-state. It is now possible to predict the effectiveness of P fertilizers, whatever their chemical form when this method is applied on soil samples where P fertilizers were applied.This paper was originally submitted as part of the special issue on Evaluation of the Agronomic Effectiveness of Phosphate Fertilizers through the use of Nuclear Related Techniques edited by F. Zapata     

人Leptin基因的克隆及其在大肠杆菌中的表达

目的克隆Leptin基因,构建其重组表达菌株,并对表达产物进行免疫学鉴定。方法利用RT-PCR方法从脂肪细胞RNA中扩增出人瘦素前体(pre-Leptin)的cDNA片段和去信号肽序列的Leptin成熟基因片段,并插入pET32a中,转化大肠杆菌BL21(DE3),获得表达重组人瘦素(rh-Leptin)的菌株。结果DNA序列分析显示获得的pre-Leptin和成熟基因片段的序列与预计序列一致,菌株诱导后经SDS-PAGE检测,rh-Leptin表达量达菌体总蛋白的40%以上。Western blot分析显示重组Lep-tin具有免疫学活性。结论已获得高效表达Leptin的重组菌株。     

大肠杆菌肉碱脱水酶基因的克隆、测序及高效表达

［摘 要］目的 克隆并表达大肠杆菌肉碱脱水酶基因。方法 用聚合酶链反应（PCR）从大肠杆菌K12s中扩增大肠杆菌肉碱脱水酶基因caiB，测定其DNA序列，将caiB基因重组到T7启动子控制下的表达载体pET－28a（＋）中，构建表达质粒pETCaiB，转化大肠杆菌BL21（DE3），用1mmol/L异两基硫代-β-D半乳糖苷（IPTG）诱导表达。结果 克隆得到的肉碱脱水酶编码基因 caiB长度为 1221bp，与文献报道值相比,DNA序列有26个不同，氨基酸序列只有一个不同，即302位的丙氨酸变为苏氨酸。重组菌经IPTG诱导，可高效表达，SDS－PAGE分析表达蛋白相对分子质量约43000，表达产物含量占菌体总蛋白45％以上。结论 得到了高效表达肉碱脱水酶的重组菌，为制备L-肉碱创造了条件。     

Evidence for (E,Z)-8,10-dodecadienyl acetate as the major component of the sex pheromone of the eastern pine seedworm,Cydia toreuta (Lepidoptera: Tortricidae)

The sex pheromone ofCydia toreuta (Grote), the eastern pine seedworm, was investigated using electroantennogram (AG) measurements, gas chromatography (combined GC-FID-EAD) measurements, and field tests. (E,Z)-8,10-dodecadienyl acetate (E,Z8,10-12:Ac) and (E,E)-8,10-dodecadienyl actetate (E,E8,10-12: Ac) produced both the highest EAG and EAD responses. Only a single antennal stimulatory peak was observed when female abdominal tip extracts were analyzed by GC-FID-EAD, which corresponded exactly with that of authenticE,Z8,10-12: Ac. Field tests confirmedE,Z8,10-12: Ac as the major pheromone component. TheE,Z isomer by itself caught equivalent numbers of male moths as did caged females. The addition of theE,E isomer to theE,Z form increased trap catch, although not significantly (P = 0.05). The addition of (Z,Z)-8,10-dodecadienyl acetate to theE,Z isomer significantly (P=0.05) reduced trap catch, while the addition of (Z,E)-8,10-dodecadienyl acetate to theE,Z form also decreased trap catch, but not significantly (P=0.05).     

基于Pro／E参数化斜齿轮建模技术

应用Pro／E软件的参数化造型功能，不需要二次开发，直接创建渐开线斜齿圆柱齿轮模型，对直齿、人字齿齿轮的建模具有借鉴作用。