Ba原子6pnd自电离态实验研究

采用三步孤立实激发与偏振光激发相结合的技术将Ba原子分别从中间态6snp1D2(n=7～41)和6snp3D2(n=7～29)激发到6p1/2nd以及6p3/2nd自电离态,从而获得了这4个系列的自电离光谱.采用Lorentz线型拟和的方法对这4个系列的光谱所展现的不同的光谱特性及其所反映的物理意义做了详细的分析.     

Ba原子6pnd自电离态实验研究

采用三步孤立实激发与偏振光激发相结合的技术将Ba原子分别从中间态6snp1D2(n=7～41)和6snp3D2(n=7～29)激发到6p1/2nd以及6p3/2nd自电离态,从而获得了这4个系列的自电离光谱.采用Lorentz线型拟和的方法对这4个系列的光谱所展现的不同的光谱特性及其所反映的物理意义做了详细的分析.     

外电场中Ba原子6pnk自电离态光谱的测量

介绍了一种可调谐激光三步孤立实激发方式测量外电场中原子自电离态光谱的技术.利用该技术结合适当的激光偏振组合方式,系统地测量了大量的Ba原子初态为M=0和|M|=1 Stark态的6pnk自电离态光谱,并且对这些实验光谱进行了初步的分析.分析结果得出这些自电离态光谱由于电场的作用,它们之间产生了强烈的混和从而导致了它们线形的变化.     

外场中Ba原子6pnk自电离态光谱的测量

介绍了一种可调谐激光三步孤立实激发方式测量外电场中原子自电离态光谱的技术.利用该技术结合适当的激光偏振组合方式,系统地测量了大量的Ba原子初态为M=0和|M|=1 Stark态的6pnk自电离态光谱,并且对这些实验光谱进行了初步的分析.分析结果得出这些自电离态光谱由于电场的作用,它们之间产生了强烈的混和从而导致了它们线形的变化.     

外电场中Ba原子6pnk自电离态光谱的测量

介绍了一种可调谐激光三步孤立实激发方式测量外电场中原子自电离态光谱的技术。利用该技术结合适当的激光偏振组合方式 ,系统地测量了大量的 Ba原子初态为 M=0和 |M|=1 Stark态的 6pnk自电离态光谱 ,并且对这些实验光谱进行了初步的分析。分析结果得出这些自电离态光谱由于电场的作用 ,它们之间产生了强烈的混和从而导致了它们线形的变化。     

带传动优化设计

一、计算公式和图表计算公式:D:=。.。。智(1)_五__一n:一0 D299xD:(2) 一_.八:,。_七p二兀U也+名a十一{下、曰m= 己DZ+D- 2 D,一D,、△=一气矛一一少 ‘(3) _Lp一弃D In..二尸j下一一,l—丫4一一一一-一一(Lp一几Dm)2一(4)“l==1忿0~D:一D: ax巡 介(5)二==悠奎雪一(〔P〕二‘一〔P〕 (P。+△P。)K。KL)(6)△p。==K、nl‘,一公,‘7,__。,K^p了2.5一K。\F。=500任书苦、叹卫气二竺:乞、+qv名(8,)几.一,“VE\K以/’、’Q二ZEFOS‘n誉‘”,B二(E一1)e+Zf(10) 符号:D二、△-一中间变量,mrnji—传动比,n:—小轮转速,rpm,D:、D:…     

1996年全国风机、水泵节能产品推荐名录

序号产品名称砚格型号上要技术参数主产厂家faiJI7锅炉给水泵D.I）（iQ—6:Z～川Olll’/11厂一m卜-1680Tll直昌水泵厂臼贡第_二水泵厂个州水泵厂哈尔滨水泵厂沈阳水泵厂保定水泵厂唐山巾水泵厂承德水泵厂口照水泵厂广州水泵厂甫庆第二:水泵厂J（}tit”Q一1～60113/h11一24—22411张家港工业给水泵厂8（刁刁1”八Q—350～2400n13/hH一1700～280011沈阳水泵厂9IX“（=35130m3/hH-82～1082[11博山水泵厂IO11热水循环泵￡Q=已3129llTI:/jh11一2（）～门sll日照水泵厂个州水泵厂龙岩水泵厂广州水泵厂唐山水泵厂RxlQ一6～旧（〕nl3门l厂…     

压缩机计算例题集(三)

ⅩⅧ.飞 轮 18.1 飞轮计算式 GD～2=16.2×10～3×（?）（18.1） 式中G——飞轮轮縁重量 吨; D——飞轮轮縁重心直径 米; C（?）——能量变动系数=6.5-0.15 C——许容速度变动系数=1/40 n——转数 转/分 N（?）——轴功率 马力 18.2 例题 1）试求 D=2.31米,C～e=0.155,C～s=1/40,n=120,N（?）=300时的飞轮轮縁的重量。     

多接收双聚焦等离子体质谱法测定高精度同位素比

采用 VG Axiom型多接收双聚焦等离子质谱仪 ( MC-ICPMS)测定 Nd、Pb、U同位素比值 ,应用指数公式对测定的结果进行质量歧视校正。结果表明 :测定参考物质 Ames Nd获得的钕同位素比值为 14 3 Nd/14 4 Nd=0 .5 1 2 1 44± 0 .0 0 0 0 1 5 (确认值为 0 .5 1 2 1 3 5 )、14 5Nd/14 4 Nd=0 .3 4841 7± 0 .0 0 0 0 1 9(确认值为 0 .3 4841 8) ;测定参考物质 NIST SRM981获得的铅同位素比值为 2 0 8Pb/2 0 4Pb=3 6.71 1 4± 0 .0 0 81、2 0 7Pb/2 0 4Pb=1 5 .4886± 0 .0 0 3 8、2 0 7Pb/2 0 6Pb=0 .91 44 5 6± 0 .0 0 0 0 3 9、2 0 6Pb/2 0 4Pb=1 6.93 82± 0 .0 0 3 1、2 0 8Pb/2 0 6Pb=2 .1 660 1± 0 .0 0 0 1 6;测定参考物质 NIST SRM 0 1 0获得的铀同位素比值为 2 3 4 U/2 3 8U =0 .0 0 0 0 5 46±0 .0 0 0 0 0 0 3 (确认值为 0 .0 0 0 0 5 46)     

中国锅炉压力容器Ⅰ级无损检测人员第五期考试超声专业试题标准答案(一九八七年)

一、是非题 1.(O)2.(x)3.(O)4.(又)5。(O)6.(x)7.(x)8.(x)9.(O)10.(x)11.(O)12。(火)13。(x)14.(O)15.(义)16.① (O)②、(x)③④⑤(欠) 二、选择题 1。人B DZ。A B3。BA4 .A BS。A入6 .B 7 .D 8.C9。D 10。D 三、填空题1 .N=DZ/4久0,=sin一‘1。22。入/D 1 .6N2.衰减由声束扩散引起的衰减由散射引 起的衰减由吸收引起的衰减3.厚度超声波在压电材料中的传播速度 1/24.椭圆一个波长0.95.频率频散6。25二7.探头水平偏心量8。纵向垂直面状9。令奋甘10。小晶片大K值短前沿高频率n.测长线I区 四、问答题 1。答:超声检验仪和探头的组…     

低压燃油雾化喷嘴流动能量损失特性数值研究

建立了描述燃油在有渐扩切向槽的低压燃油喷嘴内的三维流动数学模型,采用SIMPLE算法进行计算,探讨低压下这种喷嘴的流动阻力特性,并采用试验方法研究了低压下油的雾化特性,以确定优化的燃油雾化喷嘴的结构特性。结果表明：在θ= 6o左右时,燃油雾化喷嘴出口流体的回流卷吸作用消失;在低压下(p0=0.8 Mpa),当燃油雾化喷嘴的结构特征为n=3～4,L≤2.5,θ=5o~6o,a/b=1.2和Rx/rb≥2.5时,能量损失达到最小,喷嘴压降达到最低;结构优化的燃油雾化喷嘴在低压下可保持良好的雾化质量。研究得到的燃油雾化喷嘴可用于火电厂、化工及建材等燃烧动力装置的燃烧点火及助燃等。     

HPLC-ESI/MS鉴定十字花科植物中完形硫代葡萄糖甙

采用高效液相色谱 -电喷雾电离串级质谱 (HPLC-ESI/MSn,n=1～ 2 )分别测量羽衣甘蓝及苔菜和样准样品中完型硫代葡萄糖的保留时间和负离子质谱 ,并用这种比较方法确认十字花科植物中 8种未知硫化葡萄糖甙。在 MS质谱中观察到硫代葡萄糖甙峰 [M-K]-,在 MS2 质谱中所有硫代葡萄糖甙都产生 m/z 75和m/z97的碎片峰 ,分别是 [S=C=N-OH]-和 [HSO4]-离子。另外还观察到了和硫代葡萄糖甙侧链有关的 [R-(C=NOH) -S]-离子。     

Tribological Studies of Some Quinoline Derivatives and Their Synergistic Interaction with Phosphate Ester

Antiwear properties of metal and sulfur-free synergistic formulations containing quinoline derivatives (QDs)—4-N-(7-chloroquinolin-4-yl)-1-N,1-N-diethylpentane-1,4-diamine (QD-1), 4-N-(6-methoxyquinolin-8-yl)pentane-1,4-diamine (QD-2) and 1-N,1-N-diethyl-4-N-(6-methoxy quinolin-8-yl)pentane-1,4-diamine (QD-3)—with triphenyl phosphate (PE) in polyethylene glycol (PEG) at a very low concentration, 0.25% w/v of each, have been studied on a four-ball tester using ASTM D4172 and D5183 standards. Phosphorus content in the formulations was significantly reduced compared to the frequently used antiwear additive zinc dialkyldithiophosphate (ZDDP) and it was much lower than the allowed concentration suggested by various norms. The synergistic admixtures, SQD-2 and SQD-3, significantly improved the antiwear properties of base lube compared to the ZDDP/PE/QDs alone but the behavior of SQD-1 is comparable to that of ZDDP. Minimum values of mean wear scar diameter and average coefficient of friction were found to be 0.458?mm and 0.034, respectively, for SQD-3, the admixture with the maximum antiwear efficiency. However, these values were 0.538?mm and 0.083, respectively, for ZDDP, and for base oil the values were 1.185?mm and 0.126, respectively. The load-carrying capacity was found to be much higher for the synergistic formulations than for ZDDP.

Atomic force microscopy (AFM) and scanning electron microscopy (SEM) micrographs of the wear track support the tribological behavior of the above additives. The presence of nitrogen, oxygen, and phosphorus in energy-dispersive X-ray (EDX) spectra of the worn surface lubricated with SQDs indicates the adsorption of additive on the surface. The magnificent tribological behavior of SQDs may be attributed to the tribochemical film formed on the steel surface invoking phosphorus–nitrogen synergy. Quantum chemical calculations (density functional theory) for interactions of QDs with a steel surface agree well with the experimental observations.     

Automated Microscope-Absorption-Spectrophotometry Of Rock-Forming Minerals In The Range 40,000–5000 Cm−1 (250–2000 Nm)

To measure polarized absorption spectra of microcrystals of 3dⁿ-ion bearing silicate minerals, computer processed, microscope-spectrophotometric methods have been developed. Absorbance, log (I₀/I), can be measured with high relative accuracy (near u.v. and vis: ±0·002 to 0·001; n.i.r.: ±0·004 to 0·002), and relatively small spectral band widths are available. Hence, weak spin-forbidden dd-bands of 3dⁿ-ions can be recognized alongside spin-allowed dd-transitions without artificial broadening of absorption bands due to finite resolution. The smallest area from which absorption spectra can be taken is 8 μm in diameter. As one example of the many applications in mineralogy and material sciences, absorption spectra of a natural spessartine garnet, Spess_69·7Alm_30·0Gross_0·05, containing Mn²⁺, Fe²⁺, and traces of Fe³⁺ as 3dⁿ-ions, and of a pure Mn²⁺-garnet, Spess₆₇Gross₃₃, are presented. From these it is evident that bands in natural spessartines at ～ 26,900, 23,200 cm^?1 which were assigned to dd-transitions in Fe³⁺⁽⁶⁾, have to be reassigned to Mn²⁺⁽⁸⁾. Comparison of spectra obtained with the microscopic equipment described with those obtained by means of conventional macroscopic equipment prove that the methods described produce true spectra.     

Temperature diagnostics of ECR plasma by measurement of electron bremsstrahlung

The x-ray bremsstrahlung spectrum emitted by the electron population in a 14.5 GHz ECR plasma source has been measured using a NaI(Tl) detector, and hence the electron temperature of the higher energy electron population in the plasma has been determined. The x-ray spectra for Ne and Ar gases have been systematically studied as a function of inlet gas pressure from 7 × 10(-7) mbar to 7 × 10(-5) mbar and for input microwave power ～1 W to ～300 W. At the highest input power and optimum pressure conditions, the end point bremsstrahlung energies are seen to reach ～700 keV. The estimated electron temperatures (T(e)) were found to be in the range 20 keV-80 keV. The T(e) is found to be peaking at a pressure of 1 × 10(-5) mbar for both gases. The T(e) is seen to increase with increasing input power in the intermediate power region, i.e., between 100 and 200 W, but shows different behaviour for different gases in the low and high power regions. Both gases show very weak dependence of electron temperature on inlet gas pressure, but the trends in each gas are different.     

Investigation of hole states near the Fermi level in Nb(1-)(x)Mg(x)B(2) by electron energy-loss spectroscopy and first-principles calculations

The fine structures of the electron energy-loss spectra (EELS) for the B-K edge have been examined in NbB(2) and superconducting Nb(0.75)Mg(0.25)B(2). The experimental results are analyzed based on the calculations of density functional theory (DFT) using the Wien2k code. The results of the EELS spectra and the angular decomposition of the density of states (DOS) reveal that both the B p(z) and B p(x)+p(y) states in NbB(2) have large weights at the Fermi energy due to intersheet covalent bonding with notable hybridization between the Nb 4d and B 2p states. This kind of hybridization also results in different core-hole behaviors for the B-K edge in two orthogonal crystallographic orientations. The best fit between experimental and theoretical data is achieved with consideration of the core-hole effect of the B 1s states, in particular for the q perpendicular c spectra. Analysis of the electronic structure of the Nb(1-)(x)Mg(x)B(2) superconductors suggests that confinement of the intersheet covalent bonding is likely to be favorable for the improvement of superconductivity in this kind of materials.     

Effect of Reynolds numbers on flow past four square cylinders in an in-line square configuration for different gap spacings

In this paper two-dimensional (2-D) numerical investigation of flow past four square cylinders in an in-line square configuration are performed using the lattice Boltzmann method. The gap spacing g = s/d is set at 1, 3 and 6 and Reynolds number ranging from Re = 60 to 175. We observed four distinct wake patterns: (i) a steady wake pattern (Re = 60 and g = 1); (ii) a stable shielding wake pattern (80 ≤ Re ≤ 175 and g = 1); (iii) a wiggling shielding wake pattern (60 ≤ Re ≤ 175 and g = 3) and (iv) a vortex shedding wake pattern (60 ≤ Re ≤ 175 and g = 6). At g = 1, the Reynolds number is observed to have a strong effect on the wake patterns. It is also found that at g = 1, the secondary cylinder interaction frequency significantly contributes for drag and lift coefficients signal. It is found that the primary vortex shedding frequency dominates the flow and the role of secondary cylinder interaction frequency almost vanish at g = 6. It is observed that the jet between the gaps strongly influenced the wake interaction for different gap spacing and Reynolds number combination. To fully understand the wake transformations the details vorticity contour visualization, power spectra of lift coefficient signal and time signal analysis of drag and lift coefficients also presented in this paper.     

硝基化合物的质谱研究

2,6—DNT、2,4,6—TNT、3,5—DNT、3,4,5—TNT、1,3,5—三硝基—1,3,5—三氮杂环已烷(RDX)、1,3,5,7—四硝基—1,3,5,7—四氮杂环辛烷(HMX)以及杂环硝胺偕二硝基化合物的裂解机理是用电子轰击方法研究的。在芳香硝基化合物中突出的反应机理是消去OH基的“邻位效应”和C—NO_2键裂分反应。RDX和HMX的裂解机理以典型的丢失结构单元CH_2NNO_2和基团NO_2、HNO_2、NO为特点。杂环硝胺偕二硝基化合物的裂解机理是以典型的丢失基团如NO_2、NO、HNO_2为特点。