N II离子禁戒跃迁几率的理论计算

用多组态Dirac Fock方法 ,系统考虑了相对论效应、电子关联、延迟效应等重要贡献 ,计算了NII离子 2p3d— 2p2 以及 2p3d— 2p3p (ΔL =± 2 ,ΔS =± 1)禁戒跃迁的几率 .与已有的理论相比 ,目前计算的精度有了明显提高. The forbidden transition probabilities have been calculated for the 2p3d -2p 2 and 2p3d-2p3p(ΔL=±2, ΔS=±1) spectra of N II by using a large-scale multiconfiguration Dirac-Fock (MCDF) method. The most important effects of relativity, correlation, and relaxation are considered in the calculation Comparing with other calculations, a remarkable improvement is achieved.     

共振光散射法测定三聚氰胺

应用共振散射光谱技术建立三聚氰胺检测新方法。三聚氰胺可使甲醇体系在567nm处的共振散射光明显增强。在优化实验条件下,体系的ΔI值与三聚氰胺的浓度在0.7—16.0mg/L之间具有良好的线性关系,线性方程为ΔIRLS=40.53C(mg/L)-2.64,r=0.9993;检出限为0.21mg/L;样品加标回收率为92.6%—102.3%。方法灵敏,操作简便,分析成本低,用于奶粉中三聚氰胺的测定,结果满意。     

Cl HN_3产生NCl(a~1Δ)和NCl(b~1Σ)的实验研究

对利用微波放电直接解离 Cl2 生成 Cl,Cl与 HN3 反应生成 NCl(a1Δ)和 NCl(b1Σ)的过程进行了实验研究。得到了较强的 NCl(a1Δ)和 NCl(b1Σ)自发辐射光谱 ,考察了 Cl2 流量和 He/ Cl2 配比对NCl(a1Δ)和 NCl(b1Σ)生成的影响。发现对于一定的 He流量 ,Cl2 流量对 NCl(a1Δ)和 NCl(b1Σ)生成的影响存在一最佳范围 ,而最佳 He/ Cl2 配比不是一定值 ,而是随 He流量升高而变大 ,在实验所考察的 He流量范围 (5～ 4 0 L/ min)内 ,最佳 He/ Cl2 配比在 3 0∶ 1～ 1 0 0∶ 1之间     

一种错误的误差传递公式

中学物理实验参考资料《有效数字和误差》(山西人民出版社,1984年)练习题五2—(4)题中(p.71)给出函数式 f=ab/(a-b)(ab) (1) 在练习题答案中又给出了(1)式的偶然误差传递式(p.76),f的相对误差δf为δf=Δa/a+Δb/b+(Δa+Δb)/(a-b) (2) 公式(2)是一个错误的误差传递公式。因为根据误差传递理论,间接测量偶然误差进行算术合成时,任意函数的通用误差传递式(相对误差)为ΔF/F=|     

BPR氧化减色法测定过氧化氢亨利常数

利用冷阱收集气-液平衡管出来的气相过氧化氢,以及氯化血红素(Hemin)催化下溴邻苯三酚红(bromopyrogallolred,BPR)被过氧化氢氧化减色的分光光度法检测,测定了温度依赖的过氧化氢亨利常数。在10~35℃的范围内,过氧化氢亨利常数KH(mol·L-1·atm-1)表达为lnKH=a/T-b,其中a=7269±22,b=13·26±0·08,T为温度(K)。过氧化氢溶解焓ΔH为60·43±0·18kJ·K-1·mol-1。     

149Gd(b1)和153Dy(b1)超形变带能量的ΔI=2Staggering

粒子一转子模型推广到用于描述A-150区奇A梭超形变核态,首次成功地拟合了¹⁴⁹Gd(b1)和¹⁵³Dy(b1)能量的ΔI=2 Staggering.     

铁(Ⅱ)异腈配合物与三甲基胺氮氧化物氧原子转移反应动力学及其机理研究

在CH2 Cl2 介质中研究了铁 (Ⅱ )异腈配合物 [FeL5(CN) ]Br(1 ,L = CNCH2 Ph)和trans [FeL4(CN) 2 ] (2 ,L = CNCH2 Ph)等与氧原子转移试剂 (CH3) 3NO的反应动力学行为 ,研究结果表明 :配合物 1与 (CH3) 3NO反应遵从二级速率定律 ,反应速率 =k2 [铁异腈配合物 ]× [(CH3) 3NO]。反应的活化熵ΔS≠ 和活化焓ΔH≠ 分别为- 2 5 34± 1 67cal·(mol·K) - 1 和 1 2 71± 0 49kcal·mol- 1 ,而配合物 2不与氧原子转移试剂反应。认为反应以缔合机理进行。     

应用不同光谱技术,动物RBC,Hb及人皮肤表面血流氧化-还原状态检测

目的:检测与分析实验动物血液RBC(RBC·O2,RBC·CO2),Hb(HbO2,HbCO2)和人体皮肤表面流动血液氧化·还原状态的成像与未成像可见光谱领域OD值特征,并为该技术对白癜风病表皮黑色素颗粒检测中的应用尊定基础。方法:利用不同光谱技术和invitro和invivo检测手段,统计分析血液不同状态下波长与位置的OD值信息。结果:invitro检测:动物血液Hb·O2和RBC·O2两者在可见领域均有367,414(Soret带)nm与541,576(Q带)nm的吸收峰位;血液Hb·CO2和RBC·CO2均有432(Soret带)与和553(Q带)nm的波长吸收峰位;血液RBC状态和Hb溶血状态波长吸收峰位无改变,只是在氧化与还原状态下有完全独立的吸收峰位,血液RBC状态和Hb溶血状态波长吸光度OD值之间,有显著性差异(p<0·01)。浓度为1·5×107cell·mL-1的RBC·O2和Hb·O2在576nm的吸收峰位吸光度(y)与红细胞浓度(x)做成两条回归曲线:既,Hb·O2(b1)^y=0·05 0·983x;RBC·O2(b2)y^=0·127 1·934x,两者之间差异有显著性(p<0·01)。invivo检测:在人手背皮肤表面ImSpector图像中RBC·O2状态在540,576nm,RBC·CO2状态在555和755nm处有吸收峰。选择(a:指甲,b:指,c:手背)三个点位分别进行波长检测,每点(n=10)545nm吸收峰的平均OD值,依次为0·83±0·001,0·73±0·001和0·62±0·001,其三处测定点的OD值之间有显著性差异(p<0·01)。结论:invitro检测的RBC与Hb两者波长吸收峰位不变,但吸光度OD值不同,认为RBC状态测定结果更接近于活体组织血管内原始状态。invivo检测对人体无任何侵袭与损伤,灵敏度高,测试时间短,并且同时获得被测样品的波长与位置信息画面等优势,有望表皮中黑素等有色颗粒的直接检测。     

半掺杂钙钛矿Pr_(0.5)Sr_(0.5)CoO_3中磁熵变的标度律研究

对半掺杂氧化钴Pr0.5Sr0.5Co O3在居里温度(TC≈232 K)附近的磁熵变(ΔSM)进行了研究.研究表明,磁熵变的最大值(ΔSmaxM)依赖于外磁场强度(H):ΔSmaxM~Hn,其中n=0.55±0.14;半高宽(δTFWHM)与H有如下关系:δTFWHM~H0.4±0.1;而相对制冷能力(RCP)与H几乎呈线性关系.另外,在不同的温度和磁场强度下测得的磁熵变(ΔSM(T,H))能够重新标度为一条普适的曲线.依据该唯象的普适曲线,能够较准确的计算出在不同温度和磁场强度下磁熵变的大小.     

流动注射化学发光增强法测定焦性没食子酸

在较低 p H值的 Na OH介质中 ,焦性没食子酸对 Luminol- K3 Fe(CN) 6化学发光体系有很强的增敏作用 ,据此建立了焦性没食子酸的测定方法——流动注射化学发光增强法。该法的化学发光增强值 (ΔI)与焦性没食子酸浓度 (在 3.0× 10 -9— 1.0× 10 -6mol/ L范围内 )呈良好的线性关系 ,检出限为 1.0× 10 -9mol/ L(n=11) ,对 5× 10 -8mol/ L焦性没食子酸测定的相对标准偏差为 2 .8%。用于没食子酸热解产物中的焦性没食子酸测定 ,结果令人满意     

牙齿洁白产品体外灌流过氧化氢缓释量及其动态变化测定方法的研究

为保证牙齿洁白产品在漂白使用过程中的安全性 ,需建立一种合理的装置和简便的方法来测定该产品的过氧化氢释放量。针对洁白牙贴的使用特点及过氧化氢缓释特性 ,设计了一种体外灌流装置 ,研究了分光光度法测定产品缓释过氧化氢的动态过程。考察了过氧化氢含量测定方法及灌流装置的有效性 ,并应用于几种产品的过氧化氢缓释量测定     

环形谐振器辅助马赫-曾德尔干涉仪型波长交错滤波器的研究

将环形谐振器与马赫-曾德尔干涉仪相结合,利用谐振器反馈回路引入的相位调节效应,选择合适的谐振器耦合角,设计出一种具有最大平坦滤波响应的环形谐振器辅助马赫-曾德尔干涉型波长交错滤波器.与普通马赫-曾德尔干涉型波长交错滤波器相比,不仅阻带抑制(>38dB)和过渡带滚降特性明显加强,而且在通带中心15 GHz范围,将色散降低到±10 ps/nm以内,从而可以有效避免对传输信号造成失真.在此基础上,进一步研究环周长(Lr)与马赫-曾德尔干涉臂长差(△L)之间的关系,指出波长交错滤波器奇偶输出端口的带宽分配比直接决定于Lr/△L,当调整Lr/△L=1/2,可以实现具有1;2非对称带宽分配特性的新型波长交错滤波器,为10 Gb/s向10 Gb/s 40 Gb/s系统升级提供一种简单、灵活的方式.     

Probing configuration mixing in 12Be with Gamow-Teller transition strengths

We present a novel technique for studying the quenching of shell gaps in exotic isotopes. The method is based on extracting Gamow-Teller (ΔL=0, ΔS=1) transition strengths [B(GT)] to low-lying states from charge-exchange reactions at intermediate beam energies. These Gamow-Teller strengths are very sensitive to configuration mixing between cross-shell orbitals, and this technique thus provides an important complement to other tools currently used to study cross-shell mixing. This work focuses on the N=8 shell gap. We populated the ground and 2.24 MeV 0+ states in 12Be using the 12B(1+) (7Li, 7Be) reaction at 80 MeV/u in inverse kinematics. Using the ground-state B(GT) value from β-decay measurements (0.184±0.007) as a calibration, the B(GT) for the transition to the second 0+ state was determined to be 0.214±0.051. Comparing the extracted Gamow-Teller strengths with shell-model calculations, it was determined that the wave functions of the first and second 0+ states in 12Be are composed of 25±5% and 60±5% (0s)4(0p)8 configurations, respectively.     

Investigation of a quasi-bound T = 2 (NΔ) state with increased lifetime of the Δ

The (NΔ) system has been investigated to see whether a quasi-bound state exists for which the lifetime of the Δ is considerably increased. The (NΔ) interaction using π- and ρ-meson exchange has been studied for various approximations. In particular, the Δ-nucleon mass difference and the Δ-width have been included leading to a complex (NΔ) potential. One finds that the (T = 2, J^P = 2⁺ state is bound with a binding energy of 10 to 40 MeV depending on the type of potential used and on the regularization range. Furthermore, for this state the decay width of the Δ is strongly reduced by binding effects and the Pauli principle. The reduction amounts to a factor of three to five.     

Color-scheme interpretation of new phenomena in charged-current neutrino reactions

Productions and subsequent decays of a fully-colored hadron in neutrino reactions are studied in the framework of the interaction scheme proposed previously. It is shown that various new phenomena, i.e. ΔS = ?ΔQ, dimuon and (ωe) events, are reasonably accommodated in our color scheme.     

孟塞尔色序系统与CIE1931标准色度系统转换新算法

孟塞尔色序系统到CIE标准色度系统的自动转换在颜色和视觉领域是一个很重要的课题.提出了一种基于等色调线和等彩度线插值的新算法,实现孟塞尔色序系统与CIE1931标准色度系统之间颜色的相互转换.实验测试表明,由孟塞尔系统到CIE色度系统的正向转换准确度为ΔY=0.004,Δx=0.000 13,Δy=0.000 13,由CIE色度系统到孟塞尔系统的反向转换准确度达到了ΔV ≈0,ΔH=0.017 5,ΔC=0.013.     

甲钴胺与牛血清白蛋白相互作用的光谱特性

应用荧光光谱法、紫外吸收光谱法及共振光散射法,研究了甲钴胺 (Mecobalamin) 与牛血清白蛋白 (BSA) 之间的相互作用。在pH=7.40的三羟甲基胺基甲烷-盐酸 (Tris-HCl) 缓冲溶液中,随着甲钴胺浓度的增加,BSA的荧光强度、共振散射光强度逐渐减弱。通过计算不同温度(293,303,310 K)下的猝灭常数 (K_sv=5.40×10⁴,6.90×10⁴,8.00×10⁴ L/mol) 及扫描紫外吸收光谱,确定了甲钴胺对牛血清白蛋白的猝灭机理为动态猝灭。测定了该反应的表观结合常数 (K_A=1.68×10⁴,4.34×10⁴,7.90×10⁴ L/mol)和结合位点数 (n≈1)。利用热力学参数 (ΔH>0、ΔG<0和ΔS>0) 确定了分子间的作用力性质,作用力主要是疏水作用力,作用过程是自发的。同时应用同步荧光技术研究了甲钴胺对BSA构象的影响。结果表明,甲钴胺没有引起BSA构象的变化。     

Further evidence that fundamental-frequency difference limens measure pitch discrimination

Difference limens for complex tones (DLCs) that differ in F0 are widely regarded as a measure of periodicity-pitch discrimination. However, because F0 changes are inevitably accompanied by changes in the frequencies of the harmonics, DLCs may actually reflect the discriminability of individual components. To test this hypothesis, DLCs were measured for complex tones, the component frequencies of which were shifted coherently upward or downward by ΔF = 0%, 25%, 37.5%, or 50% of the F0, yielding fully harmonic (ΔF = 0%), strongly inharmonic (ΔF = 25%, 37.5%), or odd-harmonic (ΔF = 50%) tones. If DLCs truly reflect periodicity-pitch discriminability, they should be larger (worse) for inharmonic tones than for harmonic and odd harmonic tones because inharmonic tones have a weaker pitch. Consistent with this prediction, the results of two experiments showed a non-monotonic dependence of DLCs on ΔF, with larger DLCs for ΔF's of ± 25% or ± 37.5% than for ΔF's of 0 or ± 50% of F0. These findings are consistent with models of pitch perception that involve harmonic templates or with an autocorrelation-based model provided that more than just the highest peak in the summary autocorrelogram is taken into account.     

Color characteristics of the fringe-field switching liquid crystal mode depending on E- and O-modes

Color characteristics of the E- and O-modes in the fringe-field switching mode using the liquid crystal with negative dielectric anisotropy have been investigated. According to calculated and measured results for color shift up to 70° of polar angle in all directions, a cell with E-mode shows smaller color shift with varying viewing direction than a cell with O-mode in all grey levels, for instance, the color shift in a white state is much smaller in the E-mode (Δxy = 0.1819) than in the O-mode (Δxy = 0.0798). However, the color shift of the white state is strongly suppressed for both E-mode (Δxy = 0.0199) and O-mode (Δxy = 0.0093) with a dual domain structure.