ICP-AES测定饮用水源中的Cu、Mn、Pb、Cd、Zn

用ICP－AES法同时测定饮用水源中的Cu、Mn、Pb、Cd、Zn等重金属元素，具有基体效应小、测量范围宽等优点。检出限为0．2－4．0μg/L，回收率为91．5％－103．9％，相对标准偏差为0．29％－1．5％，测定密码样与实际样品，结果令人满意。     

ICP-AES法测定蒿甲醚中 Cu、Pb、Zn、As、Sb和Cd

本文有用硝酸－高氯酸消解蒿甲醚样品，ICP－AES法同时测定其中痕量的Cu、Pb、Zn、As、Sb和Cd等。研究了样品处理方法及高氯酸残余量对测定的干扰，选择了仪器最佳工作条件，考查了方法准确度和精密度，6种元素加标回收率在91％－110％范围内，RSD（n=7)为4．2％－6．5％。     

ICP—AES法测定U3O8标样中Al、Cr、Fe、Mg、P、Pb、Ti、V、W

用7402季铵－Kel-F粉萃取色层使铀和待测杂质元素分离，接着用975型ICP光量计测定U3O8标样中Al、Cr、Fe、Mg、P、Pb、Ti、V、W，回收率为95－110％，相对标准偏差≤5％。     

ICP-AES法测定松香中铁、铅、铜、锌、铝

本文研究了用ICP－AES法测定松香中的铁、铅、铜、锌、铝的方法，确定了松香中杂质元素同时测定的最佳工作条件，并对实际样品进行了AAS法对比测定，回收率在91％－104％之间，结果令人满意。该方法快速、简便、可靠，适用于出口松香的日常检验。     

内标－脉冲雾化ICP－AES测定微量体液中的Ca、Mg、Fe、Zn、P、Mn、Cu、Pb、Sr

采用内标－脉冲雾化进样法，建立了微量体液的ＩＣＰ－ＡＥＳ分析方法。对内标的选择，分析信号与进样量的关系和分析标准曲线等方面进行了研究，测定了微量体液样品中的Ｃａ、Ｍｇ、Ｆｅ、Ｚｎ、Ｐ、Ｍｎ、Ｃｕ、Ｐｂ、Ｓｒ等元素的含量，获得了较满意的结果。     

原子吸收光谱法测定中成药阿胶中铜、铬、镉、铅、砷、锑、锡和汞

本文以５０ｍｌ比色管作消化容器，硝酸－高氯酸混酸消化中成药阿胶，采用火焰原子吸收法测定其中的铜；石墨炉法测定其中的铬、镉、铅；氢化物法测定其中的砷、锑、锡。以硝酸－硫酸加过氧化氢水浴加热消化处理样品、采用冷原子法测定其中的汞，均取得较满意的结果。     

ICP-AES法直接测定重晶石中的Ca、Sr、Fe

通过碳酸钠高温熔样，热水浸取过渡除去SO4^2-和Na^2 ，酸化溶解沉淀的方法处理样品，采用ICP－AES法测定重晶石中的杂质元素钙、锶、铁，方法的检出限为3．9－8．4ng／mL，回收率为99．4％－100．3％，精密度为1．1％－1．4％。该方法快速、简便，在重晶石日常检测中具有重要的实际意义。     

ICP－AES法同时测定柠檬酸中铁、铜、钙、铅

本文介绍了ＩＣＰ－ＡＥＳ法同时测定柠檬酸中铁、铜、钙、铅的方法。试样以干法分解，盐酸溶解残渣后进行测定。回收率为９０．２％－１０５．８％，ＲＳＤ＜２．６６％。     

ICP-AES法同时测定茶叶中的锌、铁、锰、铜、镍、镁

研究了用硝酸＋硫酸＋高氯酸消解样品，用ICP－AES法同时测定茶叶中锌，铁，锰，铜，镍，镁的新方法，在选定的最佳条件下，测锌，铁，锰，铜，镍，镁的检出限分别为4．2，7.8,0.4,7.3,7.6,4.8ng.mL^-1，回收率为94．7％－104．2％，RSD为0．3％－4．7％，该法准确，快速，简便，适用于茶叶样品的测定，结果令人满意。     

在小硅化物SiX~m（X＝Be、B、C、N、O、F、Ne，m＝～4－＋2）中分子成键倾向的从头算研究

此文用从头计算法，在ＨＦ、ＭＰ２、ＭＰ３水平下，使用基组６—３１Ｇ、６—３１＋Ｇ对ＳｉＯ的等电子分子ＳｉＸｍ（Ｘ＝Ｂｅ、Ｂ、Ｃ、Ｎ、Ｐ、Ｎｅ，ｍ＝－４～＋２）进行了几何优化，并计算了相应的平衡几何构型下的振动频率，对ＳｉＯ分子，使用ＱＣＩＳＤ（Ｔ）方法考虑了不同水平下的电子相关效应，并考虑了不同基函数６－３１＋Ｇ和６－３１１＋Ｇ的影响。计算结果表明，所有分子的势能曲线都有稳定的极小值，并且键长与频率在ＨＦ、ＭＰ２、ＭＰ３水平上都呈现出明显的规律性，通过与实验上存在的稳定分子ＳｉＯ相比较，可以预言ＮＳＩｉ－和ＳｉＦ＋比其它分子有较明显的成键可能性，所以，ＮＳｉ－和ＳｉＦ＋有可能形成稳定的分子。     

直接光度法测定啤酒中微量铁

以低铁啤酒作为标准系列溶液的基体 ,抗坏血酸直接还原标准系列溶液和啤酒样品中三价铁为二价铁 ,在 p H=4 .5条件下与邻菲口罗啉络合显色 ,分别测量其吸光度进行定量分析。该方法与等离子体发射光谱法、有机相富集火焰原子吸收光谱法比较结果无显著差别 ,加标回收率为 96 %— 1 0 7%。     

黑土腐殖酸的近红外光谱测定

研究了我国黑土腐殖酸碳含量及其光化学性质,并探索了利用近红外光谱分析法(near infrared spectroscopy, NIRS)对其进行预测的潜力。针对东北典型黑土带土壤样品,利用偏最小二乘法(PLSr)建立定量模型,并用独立样本对模型进行检验。结果表明,模型对腐殖酸碳、胡敏酸碳和富里酸碳含量的预测效果很好,NIRS对富里酸碳和胡敏酸碳的465 nm(E₄)和预测结果也较好,665 nm光密度(E₆)的预测达到可接受水平。胡敏酸碳和富里酸碳含量与SOC的相关性,高于其与NIRS模型预测值的相关性,二者光化学性质与SOC的相关性则低于其与模型预测值的相关性。NIRS在简化黑土腐殖酸碳、胡敏酸碳和富里酸碳含量和光密度测定领域具有很好的应用前景,且能够反映SOC性质方面的信息。     

C.I. Reactive Black 5 decolorization by combined sonolysis and ozonation

Decolorization of the azo dye C.I. Reactive Black 5 (RB5) in solution by a combination of sonolysis and ozonation was investigated. The results showed that the optimum pH for the reaction was 11.0, and both lower and higher pH decreased the decolorization rate. Increasing the initial concentration of RB5 led to a decreasing decolorization rate. Under the experimental conditions, the decolorization rate increased with an increase in temperature. The decolorization of RB5 followed pseudo-first-order reaction kinetics. Based on the decolorization rate constants obtained at different temperatures within the range 287-338K and the Arrhenius equation, the apparent activation energy (E(a)) was calculated to be 11.2kJmol(-1). This indicated that the reaction has little dependence on temperature. The color decay was considerably faster than the decrease in total organic carbon (TOC), which was attributed to the ease of chromophore destruction. Hence the efficiency of decolorization was 84% compared with 4% of TOC removal after 5min reaction. Additionally, muconic acid, (2Z)-pent-2-enedioic acid and maleic acid were identified as main oxidation products by gas chromatography coupled with mass spectrometry (GC-MS) after 150min of reaction.     

Stability of Black Holes and Black Branes

We establish a new criterion for the dynamical stability of black holes in D ≥ 4 spacetime dimensions in general relativity with respect to axisymmetric perturbations: Dynamical stability is equivalent to the positivity of the canonical energy, ${\mathcal{E}}$ , on a subspace, ${\mathcal{T}}$ , of linearized solutions that have vanishing linearized ADM mass, momentum, and angular momentum at infinity and satisfy certain gauge conditions at the horizon. This is shown by proving that—apart from pure gauge perturbations and perturbations towards other stationary black holes— ${\mathcal{E}}$ is nondegenerate on ${\mathcal{T}}$ and that, for axisymmetric perturbations, ${\mathcal{E}}$ has positive flux properties at both infinity and the horizon. We further show that ${\mathcal{E}}$ is related to the second order variations of mass, angular momentum, and horizon area by ${\mathcal{E} = \delta^2 M -\sum_A \Omega_A \delta^2 J_A - \frac{\kappa}{8\pi}\delta^2 A}$ , thereby establishing a close connection between dynamical stability and thermodynamic stability. Thermodynamic instability of a family of black holes need not imply dynamical instability because the perturbations towards other members of the family will not, in general, have vanishing linearized ADM mass and/or angular momentum. However, we prove that for any black brane corresponding to a thermodynamically unstable black hole, sufficiently long wavelength perturbations can be found with ${\mathcal{E} < 0}$ and vanishing linearized ADM quantities. Thus, all black branes corresponding to thermodynmically unstable black holes are dynamically unstable, as conjectured by Gubser and Mitra. We also prove that positivity of ${\mathcal{E}}$ on ${\mathcal{T}}$ is equivalent to the satisfaction of a “ local Penrose inequality,” thus showing that satisfaction of this local Penrose inequality is necessary and sufficient for dynamical stability. Although we restrict our considerations in this paper to vacuum general relativity, most of the results of this paper are derived using general Lagrangian and Hamiltonian methods and therefore can be straightforwardly generalized to allow for the presence of matter fields and/or to the case of an arbitrary diffeomorphism covariant gravitational action.     

微波消解ICP-AES测定黑花生和红花生中的微量元素含量

样品加浓硝酸,在微机控温加热板上加热赶酸,再加H2O2后。采用微波消解处理样品,以电感耦合等离子体-原子发射光谱法（ICP-AES）测定了黑花生与红花生中K,Mg,Cu,Mn,Fe,Ca,Zn,Se等8种微量元素的含量。方法的回收率在89.2%—110.1%之间,相对标准偏差小于3.25%。实验证明,黑花生与红花生中均含有K,Mg,Cu,Mn,Fe,Ca,Zn,Se等多种微量元素,尤其黑花生是营养价值极高,深受人们喜爱的健康食品。     

一种改进的Beer吸收定律及其实验验证

传统Beer定律只有在入射功率密度小于几个kW时才能准确描述介质内部的光吸收,而对于较大入射功率密度情形,由于存在受激发射和自发发发过程,使得该定律不再适用。目前已有的能够分析含有吸收、受激发射和自发发射三种过程的模型都没有得出关于吸收定律的解析表达式。为此,本文在二能级系统模型中,利用LambertW函数解速率方程,推导出了吸收定律的广义解析表达式,并分析得出该广义定律的应用判据。在入射功率密度较低的情况下,该广义吸收定律可转化为传统Beer定律。通过实验测量与数值计算的对比分析,表明该广义定律能够快速准确地描述复杂介质内部的光吸收。     

有机无机肥配施黑土胡敏酸结构光谱学特征

土壤有机质是土壤的重要组成部分,在土壤肥力、环境保护、农业可持续发展等方面都具有重要作用。腐殖质作为土壤有机质的主体,对土壤的一系列性质和形态产生影响,其数量、组成和性质可以反映一定的成土条件和过程,是土壤肥力的重要指标。由于腐殖质分子组成的不确定性,各种方法均存在一定的局限性,优化寻求更为准确可靠的腐殖酸表征方法已成为当前研究的热点。施肥方式改变土壤中胡敏酸的组成与结构,但短期的影响程度难以用常规的测定技术检测出来。利用38年的黑土长期定位试验,通过腐殖质组分HA的分离和纯化,多种光谱分析方法的联合应用,从物质结构的角度分析土壤中单施有机肥和有机无机肥配施对黑土HA有机化合物的分子结构变化的影响。分析显示,M和MNPK施肥处理较CK处理均可提高土壤有机碳和HA含量,增加土壤中HA的总反应热、中温放热值、2920/1720值、脂族C含量、f450/500值,表明单施有机肥和有机无机肥配施后土壤HA芳构化程度降低,脂族含量增加,结合简单化,但M施肥处理增加幅度小于MNPK施肥处理。分析结果表明：多种光谱技术的联合应用,可以相互认证其结果的准确性。同时试验结果也证明有机无机肥配施较单施有机肥,更能提高土壤有机碳和土壤HA的脂族C含量,增加作物产量,培肥地力。     

Black holes and beyond

The black hole information paradox forces us into a strange situation: we must find a way to break the semiclassical approximation in a domain where no quantum gravity effects would normally be expected. Traditional quantizations of gravity do not exhibit any such breakdown, and this forces us into a difficult corner: either we must give up quantum mechanics or we must accept the existence of troublesome ‘remnants’. In string theory, however, the fundamental quanta are extended objects, and it turns out that the bound states of such objects acquire a size that grows with the number of quanta in the bound state. The interior of the black hole gets completely altered to a ‘fuzzball’ structure, and information is able to escape in radiation from the hole. The semiclassical approximation can break at macroscopic scales due to the large entropy of the hole: the measure in the path integral competes with the classical action, instead of giving a subleading correction. Putting this picture of black hole microstates together with ideas about entangled states leads to a natural set of conjectures on many long-standing questions in gravity: the significance of Rindler and de Sitter entropies, the notion of black hole complementarity, and the fate of an observer falling into a black hole.     

微波消解ICP-MS法测定啤酒废酵母中的微量金属元素

建立了微波消解-电感耦合等离子体质谱法(ICP-MS)同时测定啤酒废酵母粉中铜、铅、锌、铁、锰、镉、铬和砷等八种微量元素的方法。在实验中,对仪器的最佳工作参数进行了优化,选择适当的同位素,并用铑作内标元素,有效地抑制了分析信号的漂移及分子和多原子离子的质谱干扰;探讨了混合酸消解体系、消解液用量、微波消解功率及时间对测定结果的影响。以HNO₃-H₂O₂(2∶1)作为消化试剂,在0.5 MPa压力下2 min,1.0 MPa压力下3 min,1.5 MPa压力下5 min,4 mL HNO₃和2 mL H₂O₂能完全消解样品。在选定的实验条件下,对五种啤酒废酵母粉样品进行了精密度和回收率实验,方法相对标准偏差在0.94%～3.26%(n=9)之间,加标回收率在98.4%～102.6%之间。