四角切圆燃烧锅炉炉膛内流体流动的实验研究

本文采用一维ＬＤＡ技术通过旋转方法对四角切圆燃烧煤粉锅炉炉膛内的冷态空气动力场进行了实验研究,得出了该流动定量化的流动特征：中心较明显的向下流动;下部燃烧器区外旋气流沿壁面向下流动;在屏式过热器下面仍然存在较强的旋转流动。本文所提供的数据可用于数值计算结果的检验。     

Intermolecular interaction potentials of methane－argon complex calculated using LDA approaches

The intermolecular interaction potential for methane－argon complex is calculated by local density approximation (LDA) approaches. The calculated potential has a minimum when the intermolecular distance of methane－argon complex is 6.75 a.u.; the corresponding depth of the potential is 0.0163eV which has good agreement with experimental data. We also have made a nonlinear fitting of our results for the Lennard-Jones (12-6) potential function and obtain that V(R)=143794365.332/R^{12}-3032.093 / R^6 (R in a.u. and V(R) in eV).     

Chemometric Analysis of Urinary Volatile Organic Compounds to Monitor the Efficacy of Pitavastatin Treatments on Mammary Tumor Progression over Time

Volatile organic compounds (VOCs) in urine are potential biomarkers of breast cancer. Previously, our group has investigated breast cancer through analysis of VOCs in mouse urine and identified a panel of VOCs with the ability to monitor tumor progression. However, an unanswered question is whether VOCs can be exploited similarly to monitor the efficacy of antitumor treatments over time. Herein, subsets of tumor-bearing mice were treated with pitavastatin at high (8 mg/kg) and low (4 mg/kg) concentrations, and urine was analyzed through solid-phase microextraction (SPME) coupled with gas chromatography-mass spectrometry (GC-MS). Previous investigations using X-ray and micro-CT analysis indicated pitavastatin administered at 8 mg/kg had a protective effect against mammary tumors, whereas 4 mg/kg treatments did not inhibit tumor-induced damage. VOCs from mice treated with pitavastatin were compared to the previously analyzed healthy controls and tumor-bearing mice using chemometric analyses, which revealed that mice treated with pitavastatin at high concentrations were significantly different than tumor-bearing untreated mice in the direction of healthy controls. Mice treated with low concentrations demonstrated significant differences relative to healthy controls and were reflective of tumor-bearing untreated mice. These results show that urinary VOCs can accurately and noninvasively predict the efficacy of pitavastatin treatments over time.     

Defect levels in d-electron containing systems: Comparative study of CdTe using LDA and LDA + U

The defect properties in d-electron containing materials will be strongly influenced by the non-negligible on-site Coulomb interactions. However, this has been omitted in the current widely adopted standard first-principles calculations, such as LDA, leading to a large deviation of calculated results. Therefore, as a comparative case study, in this paper the defects of CdTe are investigated by first-principles calculations including standard LDA and LDA + U, and we find that LDA + U gives more accurate formation energies of the neutral point defects than the standard LDA. The same trend can be found in transition energies of the charged state defects as well. These comparative analyses show that LDA + U gives better results for the defects of CdTe than the standard LDA and requires less computing resource than LAPW, indicating it should have huge potential to model supercells with large number of atoms and strong electron interactions. Moreover, a new anion interstitial defect structure is found to be more stable than the well-known tetrahedron central anion interstitial defect structure \begin{document}${\rm{Te}}_i^a$\end{document}.     

激光二极管光束整形技术

阐述了对LD输出光束进行整形的必要性。在国内首次对目前常用的一些典型的光束整形技术的整形原理、关键技术及整形效果进行了分析、比较和评价。     

用单一循环LDA测量法研究四气门汽油机缸内滚流运动的湍流结构

本研究在一台四气门汽油机上对缸内滚流运动进行了LDA测量，通过改进测试系统提高了数据率，用低通滤波的单一循环分析法计算了湍流结构参数。结果发现，滚流的湍流结构具有尺度大、频率低的特点；滚流运动在压缩末期破碎时，湍流的自相关时间和积分时间尺度显著增加。     

大功率半导体激光侧面泵浦Nd：YAG板条激光器

用准连续６０Ｗ半导体激光侧面泵浦Ｎｄ：ＹＡＧ板条激光器，获得单脉冲能量３．５ｍＪ的激光输出，脉冲重复频率１～１００Ｈｚ，能量输出起伏小于±１％，光－光效率为１５％，斜效率为２９％。实现了声光调Ｑ、电光调Ｑ、ＢＤＮ染料和ＬｉＦ色心晶体被动调Ｑ的激光输出，最大峰值功率超过１００ｋＷ。     

旋转盘腔流场速度与压力的实验研究

本文描述一个旋转盘腔流场的实验研究。该盘腔由一个旋转盘，一个静止盘及静止的外围屏组成．实验表明在盘腔的两个盘面上都有边界层形成，在边界层中，流体除有切向速度外，还有沿径向的二次流存在。在边界层外的核心区中径向速度为零。一般来说，静盘边界层比转盘边界层向紊流转捩地要早。另外，压力的测量表明，在半径较大的区域中压力分布可由“流体以恒角速度旋转”的假设所得的结果近似。     

Structure, ordering, and bonding of half antiperovskites: PbNi3/2S and BiPd3/2S

In a model study the crystal structures of shandite (Pb₂Ni₃S₂), parkerite (Bi₂Ni₃S₂) and their Pd homologues are investigated in terms of ordered half antiperovskites AM_3/2S (A = Pb, Bi; M = Ni, Pd). This addresses fundamental questions on the structural relations, ordering and chemical bonding. From crystal structure investigations a new cubic parkerite variant is presented for Bi₂Pd₃S₂ that fits in an ordering model equivalently to shandite and parkerite. Type–antitype relations to ordered oxygen deficit perovskites are presented. With the relation to the superconductor Ni₃MgC a model is deduced that provides the complete crystal structure and symmetry in terms of the Ni and Pd ordering in antiperovskite superstructures. Therein a systematic ab initio investigation on the relative stability of shandite and parkerite structures is carried out for the first time. From the DFT modelling results the preferences of the ordering variants and the distinct differences in the atomic coordination spheres are discussed. The bonding in the systems is investigated by site projected density of states and covalent bond energy calculations.     

Narrow-bore liquid chromatography with multichannel detection in paediatric biochemistry: Analysis of phenylalanine and tyrosine in phenylketonuria

Summary In paediatric biochemistry, the analysis of drugs and endogenous compounds in preterm or low-birth weight neonates presents particular analytical problems. Sensitive techniques with small sample capacity are essential and in this context, narrow-bore (1–2mm) LC columns, coupled with appropriate low-volume detector cells and connections to reduce band dispersion, have been shown to offer significant advantages. By comparison with conventional columns an increase in sensitivity by a factor ofca. 2 can be achieved. The combination of narrow-bore columns and rapid-scanning UV detectors in reversed-phase LC enables the spectral information to be used for both peak recognition and homogeneity validation. Furthermore, “diode bunching” in the wavelength domain leads to a further two-fold increase in sensitivity. This combination of column and detector technology has been utilised in the design of a sensitive serum micro-assay of the essential aromatic amino acids in paediatric samples, capable of being used with 500nl sample, sensitive to 13pg phenylalanine and 9pg tyrosine and linear over the requisite therapeutic range.