悬置线交指型带通滤波器设计

介绍了悬置线交指型带通滤波器的设计原理和方法,利用计算机辅助设计工具进行数值计算,给出了悬置线的电路板尺寸参数,并应用仿真软件对该悬置线交指型带通滤波器进行仿真和优化设计, 通过仿真得到了该滤波器的响应曲线,与实验结果吻合的较好。     

含硫氨基酸对肉味香精风味的影响

本文研究了含硫氨基酸进行Maillard反应对肉味香精特征风味的影响。选取几种可以产生肉味风味的氨基酸,优化配比与还原糖进行Maillard反应,并进行了有关结果分析。通过正交设计安排实验,含硫氨基酸与自制鸡肉酶解物、还原糖进行Maillard反应,反应物香味感官评定,确定了含硫氨基酸在香味特征中的作用。     

On concurrence of several linear regressions and applications to problems of enzyme kinetics

In comparing several regressions E(y_ij) =α_i + β_ix_ij i = 1, 2, ..., k, j = 1,2, ..., n_i, researchers are generally interested in the following five problems: whether they have (1) equal slope, (2) equal intercept, (3) coincidence, (4) common intersection on X-axis, and (5) common intersection on (X,Y) - plane. Problems (1) - (3) can be put into the framework of the general linear hypothesis and the F-test can be used. However, problems (4) and (5) cannot be put into the general linear hypothesis because they are ratios of parameters. Hence, in this paper we consider the generalized likelihood ratio test for hypothesis testing. An application to an enzyme kinetics problem in Aniline Metabolism is demonstrated     

The Apparent‐Time Construct and stable variation: Final /z/ devoicing in northwestern Indiana1

As real‐time language data becomes increasingly available for sociolinguistic research, a growing number of studies are benefitting from it in order to study language changes in progress, some of which even explicitly seek to scrutinize the Apparent‐Time Construct itself. Vanishingly few real‐time studies, however, have focused specifically on stable sociolinguistic variables, leaving an important gap in our understanding of the Apparent‐Time Construct's abilities to model real‐time facts. In an effort to address this gap, the present study analyzes a presumably stable sociolinguistic variable – final /z/ devoicing – in extreme northwestern Indiana through real and apparent time. A series of Varbrul analyses indicate that this variable is, indeed, stable throughout the 20 years of real time covered by the data and that its stability is successfully modeled in apparent time. Additionally, similarities in /z/ devoicing between this community and some other communities where it has also been studied are identified and discussed.     

广州方言底层词"栏"与"墟

广州方言中的底层词,除保留在地名和口语中之外,有的既是口语词,同时又是构成地名的词语,本文所讨论的"栏"与"墟"就是这一类词语。通过对它们在广州方言中的留存、变异以及衍生出来的系列词语的考察,不仅可以探索它们从少数民族语言进入到汉语的过程,更能深入地了解粤语与少数民族语言的关系,而且对认识社会经济的发展给词义演变所带来的影响,也是有意义的。     

Substrate reinforcement and dialectal differences in Melanesian Pidgin

Stabilization of a new contact language involves a process of levelling, or the reduction of variants. One of the factors influencing which grammatical variants are retained in the process is substrate reinforcement – the existence in the substrate languages of a congruent structure with a similar function. This article illustrates substrate reinforcement in the development of the three current dialects of Melanesian Pidgin. First, evidence of earlier variability is presented and the sociolinguistic conditions that later led to greater stability are described. Second, five grammatical features that differentiate the dialects are examined. For each feature, it is shown first that at least two variants were previously in use. Then evidence is presented illustrating correspondence between the particular variant retained in the dialect and a feature of the substrate languages of that geographic area. Differing substrates reinforced different variants, and this accounts for these dialectal differences.     

基片温度对非晶碳硅薄膜电导的影响

在基片加热的条件下,高纯硅靶在甲烷和氩的混合气氛中,采用直流平面磁控反应溅射,可以制备具有光电响应的氢化非晶碳硅合金薄膜。本文对不同基片温度下成膜的样品进行了电导性能测试并分析了测试结果,得出了基片温度是影响该薄膜光电导的关键因素的结论。     

Si衬底上3C-SiC异质外延应力的消除

利用低压化学气相沉积方法在N型Si衬底上异质外延生长3C-SiC薄膜,研究和分析了不同碳化工艺和生长工艺对3C-SiC外延层的影响;探讨了Si衬底3C-SiC异质外延应力的消除机理。通过台阶仪和XRD对不同工艺条件下的外延层质量进行分析,得到最佳工艺条件的碳化温度为1 000℃,碳化时间为5 min,生长温度为1 200℃,生长速度为4μm/h。对最佳工艺条件下得到的外延层的台阶仪分析表明外延层弯曲度仅为5μm/45 mm;而外延层的XRD和AFM分析表明,3μm厚度外延层SiC(111)半高宽为0.15°,表面粗糙度为15.4nm,表明外延层结晶质量良好。     

LiTaO_3薄膜红外探测器热分析

利用有限元软件ANSYS对LiTaO3薄膜热释电红外探测器进行热分析;研究了敏感元绝热层的厚度与热导率以及基底的厚度及材料对热分析结果的影响;提出了优化方案,并给出优化前后仿真的对比结果。分析结果表明,探测器的热响应随绝热层的厚度增加而增加,随绝热层的热导率降低而增加。在硅、镍、蓝宝石三种基底材料中,使用蓝宝石的探测器的热响应效果最佳。在绝热层厚度为2μm的情况下,基底的厚度对探测器响应的影响可以忽略。实验测试结果证实了优化模型的有效性。     

悬置微带多路宽带功率分配器

阐述了悬置微带多路宽带新型功分器的设计理论与关键技术的具体方法，实际了该类功分器的计算机辅助设计。实际制作出三路等功率悬置微带宽带功分器在３～１８ＧＨｚ的频带内，输入驻波小于１．３，插损小于０．６ｄＢ，隔离大于１５ｄＢ。