InGaAs（P）分别限制应变单量子阱激光器的优化设计

针对较常用的ＩｎＧａＡｓ（Ｐ）分别限制应变单量子阱激光器，给出了为得到最大净增益的优化设计参数。对于激射波长为１．５５μｍ的无应变激光器，最佳的光限制层波长为１．２４μｍ，厚度为１００ｎｍ。当阱材料引入压缩应变后．由于价带的有效状态密度减小，量子阱激光器的微分增益变大，阱深的增大对增大线性增益的效果更加明显．所以最佳光限制层的波长将变短，为１．２０μｍ     

Influence of China‘s WTO Entry on Petroleum Taxation

China has formulated a series of preferential taxation policies for the country 's petroleum enterprises. Those state policies are the important factors influencing reform and development of petroleum enterprises. The taxes turned over to the State by CNPC in 1998, 1999 and 2000 are 31.4 billion yuan, 31.7 billion yuan and 41 billion yuan respectively, accounting for 11.64 percent, 9.06 percent and 10.15 percent of the annual sales income.With China 's entry into WTO, it is necessary for t…     

品种和加工方式对双低菜粕有效能和氨基酸有效性的影响_注

用精确饲喂技术评价了 3个品种的中国双低油菜和 1个加拿大卡诺拉的脱脂种籽和商品饼粕的能量和氨基酸的有效性。结果表明 ,4个脱脂种籽的氮校正真代谢能和氨基酸真消化率没有差异 (P >0 .0 5 ) ;而 4个商品饼粕的脱脂样品的氮校正真代谢能和氨基酸真消化率有极显著或显著差异。研究结果证实 ,不适当的加工方式不仅降低了氨基酸的有效性 ,而且影响家禽对能量的利用效率。     

WiMax: The Emergence of Wireless Broadband

WiMax has changed the scene of wireless broadband from proprietary solutions to a standards-based industry. Authors discuss WiMax evolution, applications, spectrum issues, standards, and developments.     

核磁共振测井在致密含气砂岩中的应用

通过对核磁共振测井的T₂谱及其T₂截至值的合理选取，解释并获得了鄂尔多斯盆地西缘上古生界山西组、石盒子组致密砂岩储集层的总孔隙度、有效孔隙度、毛细管束缚水体积、可动水体积及渗透率等参数，据此预测的储集层孔隙结构特征与岩心分析测试结果很吻合。研究还发现，致密含气砂岩的T₂谱具有分布范围窄-中等，波形及差谱分析谱位置明显后移、分布中等、呈单峰的典型特征。结合常规测井资料，综合研究了致密砂岩储层特征及其含气层的测井响应。经测试验证，致密含气砂岩储层的核磁共振测井解释结果十分可靠，表明核磁共振测井可用于该区致密含气砂岩复杂储集层评价。     

Effect of mild acid treatment on the survival, enteropathogenicity, and protein production in vibrio parahaemolyticus

Vibrio parahaemolyticus is an important food-borne enteropathogen that encounters various adverse conditions in its native environment or during infection. Effects of mild acid treatment on survival under stress conditions, enteropathogenicity, and protein production in this pathogen were investigated. Logarithmically grown cells, at pH 7.5 shifted to pH 5.0 for 30 min, were more resistant to subsequent acid challenge at pH 4.4. A two-phase adaptive procedure (pH 5.8 for 30 min; pH 5.0 for 30 min) was better than a single-phase procedure for enhancing the acid tolerance of this pathogen. The acid-adapted cells were cross-protected against the challenges of low salinity and thermal inactivation. One-dimensional polyacrylamide gel electrophoresis revealed that proteins with molecular masses of 6.4, 9.0, 13.6, 16.3, 18.9, 22.9, 24.4, 28.3, 33. 9, 36.9, 41.2, 47.6, 58.1, 65.6, 80.5, 88.2, and 96.9 kDa were induced or significantly enhanced, while proteins of 25.3, 30.1, 30. 7, and 91.7 kDa were significantly inhibited. Two-dimensional polyacrylamide gel electrophoresis revealed that 20 species of proteins were induced or significantly enhanced, while 26 species were inhibited. In assays conducted using the suckling mouse model, enteropathogenicity of the acid-adapted cells was significantly enhanced in terms of intestine/body weight ratio and in vivo recovery of infected cells.     

TiAl基合金粉末爆炸烧结特性常数的测算

本文测算了自蔓延高温合成TiAl基合金粉末的爆炸烧结特性常数值：γ＝1．44，lgβ＝25．25，并为试验证实，这为获取大尺寸TiAl基合金提供了理论依据。     

Factors regulating SCC antigen expression in squamous cell carcinoma of the uterine cervix

Expression of squamous cell carcinoma (SCC) antigen emerged concurrently with squamous formation of the uterine cervix and increased during the neoplastic transformation of the cervical squamous epithelium. SCC antigen expression differed considerably among the histomorphologic cell types of cervical carcinoma. Large cell nonkeratinizing carcinoma contained high levels of the antigen. In contrast, no appreciable expression of SCC antigen was observed in small cell nonkeratinizing carcinoma. The pattern of SCC antigen expression closely coincided with EGF receptor (EGF-R) expression in cervical squamous neoplasia. This suggests that the expression of SCC and EGF-R in cervical carcinoma is related to the differentiation or dedifferentiation processes of the tumor cells. SCC production by CaSki cervical epidermoid carcinoma cells was stimulated by EGF. It seems likely that an autocrine system, in which EGF serves as the signal, may exist in cervical squamous carcinoma. 17beta-estradiol and L-triiodothyronine were found to upregulate EGF-R expression, proliferative potential and SCC production in the CaSki cervical carcinoma cells.     

Synthesis and Properties of the Bi-Based Superconducting Powder Prepared by the Pechini Process

Bi-based superconductors are of great interest in high-temperature superconductors. We describe what is believed to be the first synthesis of these materials using the Pechini process, a low-temperature synthetic method that often yields inorganic oxide of excellent phase purity and well-controlled stoichiometry. Using this process, it has been possible to synthesize phase-pure Bi-2223 phase by calcining the appropriate polymeric precursors in air at 800°C for several hours. The superconductivity studies show that the Pechini-synthesized materials appear to offer high-quality performance.     

面向对象方法在7号信令软件设计中的应用

随着交换技术的飞速发展，程控交换软件的规模越来越大，改动也越来越频繁，如何使代码对数据的改动具有相对的稳定性成为程控软件设计的一个首要问题。本文以ＣＣＳ７（７号公共信道信令）为例，从对象模型、动态模型、功能模型３个方面阐述了ＯＯ（面向对象）方法在ＣＣＳ７软件设计中的应用。这一方法，也可应用于程控软件的设计。