混合硝酸稀土和氯化镉对小鼠骨髓嗜多染红细胞微核率的影响

以混合硝酸稀土（剂量３２、６４ｍｇ／ｋｇ）和氯化镉（剂量０．７、１．４、２．８ｍｇ／ｋｇ）对小鼠分别进行灌胃和腹腔注射处理，以测定混合硝酸稀土对氯化镉诱发的骨髓嗜多染红细胞微核率的拮抗作用。实验结果表明，两种剂量混合硝酸稀土能有效地降低不同剂量氯化镉诱发的微核率，混合硝酸稀土和氯化混合给药组与相应的氯化镉单独给药组相比，有显著性差异（Ｐ〈０．０１）。     

硒对铅诱发动物体内变化的效应

综述了实验动物体内硒和铅的相互作用。研究结果表明,硒有拮抗铅毒的作用。全文包括上部分：（１）硒对铅诱发动物生长变化的效应;（２）硒对铅诱发动物血和器官中变化的效应;（３）三对铅诱发组织脂质过氧化的效应;（４）硒对抗铅毒性的可能机理。     

土壤粒级和酸度对硒吸附固定的影响

用砖红壤样品和亚硒酸钠进行实验,结果表明,土壤粒级和酸度对硒的吸附固定有明显影响,土样粒径越小和酸度增加,对硒的固定作用加强。〉１ｍｍ粒级对硒几乎没有固定能力,〈１．０ｍｍ粒级固定作用显著增大。当ｐＨ２￣３时,粘土矿物（经电镜和Ｘ射线监定绝大多数为高岭石）固定硒的量最大,当ｐＨ〉３时,固定硒的量随ＰＨ值的增加而逐步降低,至ｐＨ６￣８时,固定能力变化不明显。     

氯化汞和亚硒酸钠对大鼠的毒性相互作用

用Hom法测定了大鼠经口染毒的LD50,并在此基础上进行90天亚慢性经口毒性试验。测量染毒过程中的体重、食物利用率的变化,测定肝、肾、脾等五种器官脏器系数,并进行血液生化检测。氯化汞、亚硒酸钠及二者等摩尔比联合作用对大鼠LD50分别为127．5、39．55和252mg/kg。汞组和硒组大鼠体重呈进行性下降。汞组肝、肾、胸腺、脾系数增大,睾丸系数减小,联合作用显著降低了汞对各脏器系数的影响,并且随着剂量组中硒剂量的增加,汞对脏器系数的影响减弱。血液学、血清酶化学检测结果无显著性差异。实验结果表明氯化汞和亚硒酸钠相互作用表现为明显的毒性拮抗作用,雌鼠对氯化汞和亚硒酸钠联合毒性有更高的耐受性。联合作用能够减弱单独作用对大鼠生长的影响,减弱汞对五种脏器的毒性。     

高危人群补硒预防肝癌的作用

通过调查、抽血检测男性20～65岁18000人,检出HBsAg+、AFP(-)、肝功能(ALT)基本正常的患者2065例,按地区随机分为补硒组1112例及对照组953例。补硒组每人每天服亚硒酸钠05mg1片,对照组则服安慰剂1片。通过服药前瞻观察2年,补硒组血硒显著升高,与对照组比较有明显差异(P<001);相应谷胱甘肽过氧化物酶随之升高,与对照组比较亦有显著差异(P<001);相反补硒组外周血淋巴细胞微核检出率显著低于对照组(P<001)。补硒组肝癌发病率170863/10万(19/1112),对照组430220/10万(41/953),有非常显著差异(P<001),进一步证实在肝癌高发区高危人群中,尤其是低硒地区,补硒可以预防肝癌,补硒方法简单,易于推广。     

硒对镉毒性的拮抗与解毒作用实验研究

不同剂量的硒对高剂量镉的拮抗作用引起大鼠全血中谷胱甘肽过氧化物酶活性和心肝、肾脏器相对重量的变化，用以评价硒对镉毒性的缓解作用，实验结果显示，经口给适量的硒对镉引起的毒性有拮抗作用，对机体有保护作用。     

补硒对预防原发性肝癌的作用

原发性肝癌病因为多因素协同作用的结果,我国肝癌病因以乙型肝炎病毒（ＨＢＶ）、黄曲霉毒（ＡＦＢ１）、饮水污染和遗传等因素为主。某些微量元素缺乏,促进了肝癌的发生、发展。科学工作者针对肝癌病因采取以“防治肝炎、管粮防霉、改良饮水、适量补硒”为中心的综合防治措施,已取得初步成效,本硒进一步阐明在肝癌高发现场应用补硒肝癌的作用。通过四年前瞻研究结果表明,食硒盐补硒组较对照组血硒ＧＳＨ－ｐｘ升高,ＵＤＳ、微     

用相关分析法探讨加硒化肥引起麦粒化学元素含量的变化

在化肥中加亚硒酸钠，培育出的富硒小麦和对照组相比，Ｓｅ、Ｓｒ明显增加（Ｐ＜０．０１）．     

硒,砷在水稻体内的相互作用及其自由基机理的研究

以水稻为对象观察了砷（ＮａＡｓＯ２）的毒性作用及硒、砷毒性的相互作用。当培养液中砷（ＮａＡｓＯ２）的浓度约大于０．１×１０－６时，砷会抑制水稻的生长。当硒（Ｎａ２ＳｅＯ３）的浓度范围在０×１０－５～１×１０－６时，硒能拮抗砷的毒性，但硒的浓度大于１×１０－６时，硒会增加体系的毒性。有关作用的机理为自由基机理。     

Cu(Ⅱ)-CV-PO_2~(3-)体系的2.5次微分极谱研究及其应用

在ｐＨ４．１醋酸盐缓冲溶液及１００℃加热条件下，痕量铜（Ⅱ）对结晶紫（ＣＶ）（Ｅｐ＝－０．６５Ｖ）氧化次亚磷酸钠的缓慢反应有很强的催化作用，采用固定时间法借自来水冷却中止反应，拟定了测定铜的催化反应－伏安法，线性范围为３～６０ｎｇ／ｍＬＣｕ，检出限为１ｎｇ／ｍＬＣｕ，方法应用于植壮素中铜的分析，获得较好结果．     

大蒜对硒的吸收及硒对大蒜生长的影响

在培养液中添加不同浓度的Ｎａ２ＳｅＯ３研究大蒜对硒的吸收以及吸收的硒对大蒜生长的影响。结果表明，大蒜对硒具有很强的生物富集作用，总硒含量为对照的６２２倍，当添加１ｍｍｏｌ／ＬＮａ２ＳｅＯ３时，有机化程度最主达７８．２４％，另外吸收的硒影响大蒜的生长，低浓度硒促进大蒜生长，１ｍｍｏｌ／ＬＮａ２ＳｅＯ为最适的促进生长浓度，并能提高大蒜中的蛋白质，可溶性糖，ＤＮＡ，ＲＮＡ含量，大蒜可作为补硒和高营养价值     

Na2SeO3在Fe电极上还原和吸附机理

采用循环伏安法、恒电势电解法、恒电流阶跃法及交流阻抗法研究Na2SeO3提高锌锰合金电沉积电流效率的作用机理.证明在锌锰合金电沉积的条件下，Na2SeO3 阴极被还原为Se32－并吸附在阴极表面上，从而阻止了氢原子在阴极表面的吸附，因而减少了氢离子的阴极还原.拟定了Na2SeO3的反应和吸附机理，用交流阻抗法进一步证明了所拟机理的正确性.     

大豆施硒试验研究

大豆叶面喷硒可明显提高籽粒硒含量。鼓粒期一次喷施亚硒酸钠水溶液效果最佳，籽粒硒含量最高可比对照提高31.71倍。叶面喷硒对大豆植株生长及产量无不良影响。     

Selenium oxoanion compounds of palladium(II)

Three new palladium compounds, PdSeO3, PdSe2O5, and Na2Pd(SeO4)2, containing selenium oxoanions of both Se(IV) and Se(VI) have been prepared under mild hydrothermal conditions. PdSe2O5 and Na2Pd(SeO4)2 both possess one-dimensional structures. Within the structure of PdSe2O5, [PdO4] square planar building blocks are joined together through diselenite, Se2O52-, anions, and form a zigzag chain along the c axis. In Na2Pd(SeO4)2, [PdO4] units are connected by two selenate, SeO42-, anions, and extend along the a axis to form a [Pd(SeO4)2]2- chain. Na+ cations reside in the space between the [Pd(SeO4)2]2- chains and act as counter cations. Unlike above two compounds, PdSeO3 exhibits a layered structure. In the structure of PdSeO3, [PdO4] units are connected to each other by corner-sharing and form a zigzag chain along the b axis. The chains are further joined together by tridentate selenite, SeO32-, anions to form layers in the [ab] plane that stack along the c axis. Crystallographic data: (193 K; Mo Kalpha, lambda=0.71073 A): PdSeO3, monoclinic, space group P21/m, a=3.8884(5) A, b=6.4170(8) A, c=6.1051(7) A, beta=96.413(2) degrees, V=151.38(3) A3, Z=2; PdSe2O5, monoclinic, space group C2/c, a=12.198(2) A, b=5.5500(8) A, c=7.200(1) A, beta=107.900(2) degrees , V=463.8(1) A3, Z=4; Na2Pd(SeO4)2, triclinic, space group P, a=4.9349(11) A, b=5.9981(13) A, c=7.1512 (15) A, alpha=73.894(4) degrees, beta=86.124(4) degrees, gamma=70.834(4) degrees, V=192.03(7) A3, Z=1.     

Laser desorption/ionization and laser ablation synthesis of new selenium oxide compounds from selenium(IV) dioxide

Laser desorption/ionization (LDI) and/or laser ablation (LA) of selenium dioxide crystals or its mixtures with sodium peroxide were studied using a commercial matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometer. It was found that LDI and LA of selenium (IV) dioxide not only ionizes SeO(2), but also leads to the formation of several positively and negatively singly charged species: SeO(n) (+) (n = 0-2), Se(2) (+), SeO(n) (-) (n = 0-4), Se(2)O(n) (-) (n = 3-7), Se(3)O(n) (-) (n = 4-9), Se(4)O(n) (-) (n = 8-10). A rather high yield of selenium species in the positive ion mode, Se(m) (+) (m = 1-8) and Se(m)OH(+) (m = 3-7), was obtained by using the MALDI approach while the species detected in the negative ion mode, SeO(n) (-) (n = 0-4), Se(2)O(n) (-) (n = 3-7), Se(3)O(n) (-) (n = 4-9), and Se(4)O(n) (-) (n = 9, 10), were the same as those observed during LDI/LA of selenium dioxide. The addition of sodium peroxide to selenium dioxide with the aim of enhancing its oxidation and thus increasing the production of SeO(4) product resulted in extensive cationization of the species with sodium or potassium. The following positively and negatively charged species were identified: Se(+), Se(2) (+), Se(2)OH(+), Se(2)ONa(+), SeO(n) (-) (n = 0-3), and Se(2)O(n) (-) (n = 0, 1, 4). Also observed in mass spectra of such mixtures, various mixed sodium and/or potassium adducts with selenium oxide species, e.g. Se(2)O(4)K(2)Na(-), were identified. In all, 26 totally new species, Se(2)O(n) (-) (n = 3-6), Se(3)O(n) (-) (n = 4-9), Se(4)O(n) (-) (n = 8-10), Se(4)O(11)H(5) (-), Se(4)O(12)H(3) (-), Se(2)O(4)Na(-), Se(2)O(5)HNa(-), Se(2)O(5)HNa(2) (-), Se(3)O(6)K(2)Na(-), Se(3)O(6)K(2)Na(2) (-), Se(2)ONa(+), and Se(m)OH(+) (m = 3-7), were described for the first time. Also, for the first time, the formation of selenium(IV) diperoxide, O-O-Se-O-O or O(2)SeO(2), is described. The stoichiometries of the compounds generated were confirmed using isotopic pattern modeling.     

Three new sodium neptunyl(V) selenate hydrates: structures, Raman spectroscopy, and magnetism

Green crystals of Na(NpO(2))(SeO(4))(H(2)O) (1), Na(3)(NpO(2))(SeO(4))(2)(H(2)O) (2), and Na(3)(NpO(2))(SeO(4))(2)(H(2)O)(2) (3) have been prepared by a hydrothermal method for 1 or evaporation from aqueous solutions for 2 and 3. The structures of these compounds have been characterized by single-crystal X-ray diffraction. Compound 1 is isostructural with Na(NpO(2))(SO(4))(H(2)O) (4). The structure of 1 consists of ribbons of neptunyl(V) pentagonal bipyramids, which are decorated and further connected by selenate tetrahedra to form a three-dimensional framework. The resulting open channels are filled by Na(+) cations and H(2)O molecules. Within the ribbon, each neptunyl polyhedron shares corners with each other solely through cation-cation interactions (CCIs). The structure of 2 adopts one-dimensional [(NpO(2))(SeO(4))(2)(H(2)O)](3-) chains connected by Na(+) cations. Each NpO(2)(+) cation is coordinated by four monodentate SeO(4)(2-) anions and one H(2)O molecule to form a pentagonal bipyramid. The structure of 3 is constructed by one-dimensional [(NpO(2))(SeO(4))(2)](3-) chains separated by Na(+) cations and H(2)O molecules. These chains have two configurations resulting in two disordered orientations of the Se(2)O(4)(2-) tetrahedra. Each NpO(2)(+) cation is coordinated by one bidentate Se(1)O(4)(2-) and three monodentate Se(2)O(4)(2-) anions to form a pentagonal bipyramid. Raman spectra of 1, 2, and 4 were collected on powder samples. For 1 and 4, the neptunyl symmetric stretch modes (670, 676, 730, and 739 cm(-1)) shift significantly toward lower frequencies compared to that in 2 (773 cm(-1)), and there are several asymmetric neptunyl stretch bands in the region of 760-820 cm(-1). Magnetic measurements obtained from crushed crystals of 1 are consistent with a ferromagnetic ordering of the neptunyl(V) spins at 6.5(2) K, with an average low temperature saturation moment of 2.2(1) μ(B) per Np. Well above the ordering temperature, the susceptibility follows Curie-Weiss behavior, with an average effective moment of 3.65(10) μ(B) per Np and a Weiss constant of 14(1) K. Correlations between lattice dimensionality and magnetic behavior are discussed.     

Comparative study of vibrational spectra of Rb4LiH3(SO4)4, K4LiH3(SO4)4, K4LiH3(SeO4)4, Na5H3(SeO4)4.2H2O and Na2SeO4.H2SeO3.H2O crystals. Polarized infrared and Raman studies

Vibrational spectra of M4LiH3(XO4)4 family, where M=K, Rb, X=S, Se together with Na5H3(SeO4)4.2H2O and Na2SeO4.H2SeO3.H2O crystals were compared. Similarities and differences are described. The spectroscopic manifestation of the presence of hydrogen bonds is discussed. Position of the bands corresponding to bending type of vibrations (in-plane and out-of plane) of hydrogen bonds is analyzed in the function of temperature. Small dynamic splitting of the bands due to weak interactions between ions is noticed.     

细胞动力学研究VIII.Na2SeO3对黑根菌作用特征

The Characteristics of the action of Na2SeO3 on Rhizopus nigrocans has been studied by means of microcalorimetry, the relationship between growth rate constants and the concentration of Na2SeO3 is
k=0.03608exp[-0.003608(c+8.60)2]
It was found that Na2SeO3 of low concentration has promoting action on the growth of Rhizopus nigrocans cells, and high concentration of Na2SeO3 has inhibitory action. The study has provided a lot of information on the bioaffect of selenium and the research of toxicology.     

Laser ablation synthesis of selenium superoxide anion SeO4- via selenium trioxide photolysis. Time-of-flight mass spectrometry and ab initio calculations

Laser desorption/ionisation and laser ablation of solid selenium trioxide, as well as the gas-phase behaviour of selenium trioxide, were studied. Selenium trioxide undergoes photochemical decomposition and, from the mass spectra obtained by laser desorption/ionisation time-of-flight mass spectrometry (LDI-TOF-MS), the following species were identified: O-, O2-, O3-, SeO-, SeO2-, SeO3-, SeO4-, Se2O7-, Se3O11-, and Se4O14-. Formation of the selenium superoxide SeO4- anion is described in this work for the first time. In addition, low-abundance selenium species such as Se2O8H2-, Se3O11H-, and Se4O15H2- were also detected. The stoichiometry of all ions was confirmed via isotopic pattern modeling and/or post-source decay (PSD) analysis. Photolysis of selenium trioxide leads partly to ozone formation. It was found that the most likely mechanisms of selenium superoxide formation are oxidation of selenium trioxide with ozone and/or reactive oxygen radicals, or photolysis of selenium trioxide tetramer (SeO3)4. Therefore, ab initio calculations were performed to support the mass spectrometric evidence and to suggest probable geometries for selenium superoxide anion SeO4- and diselenium superoxide anion Se2O7-, as well as to provide insight into and/or predict possible formation pathways. It has been found that both cyclic and non-cyclic peroxide structures of SeO4- and Se2O7- ions are possible. In addition, the SeO4 structure was also calculated guided by thermodynamic considerations using Gaussian-2 methodology, and the inferred stability of the SeO4 neutral molecule was supported by ab initio calculations.     

Atoms-in-molecules analysis of extended hypervalent five-center, six-electron (5c-6e) C(2)Z(2)O interactions at the 1,8,9-positions of anthraquinone and 9-methoxyanthracene systems

To clarify the nature of five-center, six-electron (5c-6e) C(2)Z(2)O interactions, atoms-in-molecules (AIM) analysis has been applied to an anthraquinone, 1,8-(MeZ)(2)ATQ (1 (Z=Se), 2 (Z=S), and 3 (Z=O)), and a 9-methoxyanthracene system, 9-MeO-1,8-(MeZ)(2)ATC (4 (Z=Se), 5 (Z=S), and 6 (Z=O)), as well as 1-(MeZ)ATQ (7 (Z=Se), 8 (Z=S), and 9 (Z=O)) and 9-MeO-1-(MeZ)ATC (10 (Z=Se), 11 (Z=S), and 12 (Z=O)). The total electronic energy density (H(b)(r(c))) at the bond critical points (BCPs), an appropriate index for weak interactions, has been examined for 5c-6e C(2)Z(2)O and 3c-4e CZO interactions of the n(p)(O)sigma*(Z--C) type in 1-12. Some hydrogen-bonded adducts were also re-examined for convenience of comparison. The total electronic energy densities varied in the following order: OO (3: H(b)(r(c))=0.0028 au)=OO (6: 0.0028 au)>OO (9: 0.0025 au)> or =NNHF (0.0024 au)> or =OO (12: 0.0023 au)>H(2)OHOH (0.0015 au)>SO (8: 0.0013 au)=SO (2: 0.0013 au)> or =SO (11: 0.0012 au)=SO (5: 0.0012 au)>HFHF (0.0008 au)=SeO (10: 0.0008 au)=SeO (4: 0.0008 au)> or =SeO (1: 0.0007 au)> or =SeO (7: 0.0006 au)>HCNHF (-0.0013 au). H(b)(r(c)) values for SO were predicted to be smaller than the hydrogen bond of H(2)OHOH and H(b)(r(c)) values for SeO are very close to or slightly smaller than that for HFHF in both the ATQ and 9-MeOATC systems. In the case of Z=Se and S, H(b)(r(c)) values for 5c-6e C(2)Z(2)O interactions are essentially equal to those for 3c-4e CZO if Z is the same. The results demonstrate that two n(p)(O)sigma*(Z--C) 3c-4e interactions effectively connect through the central n(p)(O) orbital to form the extended hypervalent 5c-6e system of the sigma*(C--Z)n(p)(O)sigma*(Z--C) type for Z=Se and S in both systems. Natural bond orbital (NBO) analysis revealed that n(s)(O) also contributes to some extent. The electron charge densities at the BCPs, NBO analysis, and the total energies calculated for 1-12, together with the structural changes in the PhSe derivatives, support the above discussion.