Oxygen isotope effect in high-temperature oxide superconductors

The effect of oxygen isotope substitution on the superconducting transition temperature, T(c), has been measured for BaBi(0.25)Pb(0.75)O(3) (T(c), approximately 11 K) and Lal(1.85) Ca(0.15)CuO(4) (T(c) approximately 20 K), and is compared to the shifts observed for La(1.85)Sr(0.15)CuO(4) (T(c) approximately 37 K) and YBa(2)Cu(3)O(7) (T(c) approximately 92 K). For all four materials, the transition temperature is shifted to lower temperature upon substitution of oxygen-18 for oxygen-16. The observed shifts demonstrate that phonons are involved in the electron-pairing mechanism in these oxide superconductors.     

吉林省担子菌补记（三）

报道了吉林省新分布担子菌6种，即黄环鳞伞Descolea flavoannulata(L.Vassilieva)Horak,刺毛暗皮伞Phaeomarasmius erinaceellus (Peck)Sing.,二孢长根奥德蘑Oudemansiella radicata (Relh.:Fr.)Sing.var.bispora (Redhead,Ginns et Shoemaker)Z.L.Yang et Zang，带状盔孢菌Galerina vittaeformis(Fr.)Sing.,迭生灵芝Ganoderma lobatum(Schw.)Akt．和环沟纹韧革菌Stereum strigoso-zonatum(Schw.)Cunn.。其中，刺毛暗皮伞和带状盔孢菌为中国新记录种。     

菜用大豆田节肢动物的群落特征

根据菜用大豆田节肢动物物种的组成和数量,按照营养和取食关系,将群落划分为害虫类、捕食类、寄生类和中性类亚群落,采用群落分析的多个参数比较分析了群落的结构特征.在菜用大豆田共查出节肢动物116种,分属于59科.春种和秋种菜用大豆田各亚群落的相对丰盛度分别为:害虫类(0.7018)>捕食类(0.1641)>中性类(0.0923)>寄生类(0.0418),害虫类(0.9586)>捕食类(0.0164)>寄生类(0.0145)>中性类(0.0104).各亚群落的优势集中性分别为:中性类(0.4392)>捕食类(0.1547)>寄生类(0.1468)>害虫类(0.1310),害虫类(0.8388)>寄生类(0.6878)>捕食类(0.4452)>中性类(0.2852).各亚群落的多样性分别为:害虫类(3.3957)>捕食类(3.2822)>寄生类(3.1842)>中性类(1.9607),中性类(2.3116)>寄生类(2.1081)>捕食类(1.1338)>害虫类(0.5940).各亚群落的均匀性分别为:寄生类(0.8363)>害虫类(0.7088)>捕食类(0.7068)>中性类(0.5298),中性类(0.6071)>捕食类(0.4540)>寄生类(0.3278)>害虫类(0.1264).秋种菜用大豆田多样性指数和均匀性指数较低,优势集中性较高,害虫大发生的可能性较大.     

Tunneling Spectroscopy of M3C60 Superconductors: The Energy Gap, Strong Coupling, and Superconductivity

Tunneling spectroscopy has been used to characterize the magnitude and temperature dependence of the superconducting energy gap (triangle up) for K(3)C(60) and Rb(3)C(60). At low temperature the reduced energy gap, 2triangle upkappaT(c) (where T(c) is the transition temperature) has a value of 5.3 +/- 0.2 and 5.2 +/- 0.3 for K(3)C(60) and Rb(3)C(60), respectively. The magnitude of the reduced gap for these materials is significantly larger than the value of 3.53 predicted by Bardeen-Cooper-Schrieffer theory. Hence, these results show that the pair-coupling interaction is strong in the M(3)C(60) superconductors. In addition, measurements of triangle up(T) for both K(3)C(60) and Rb(3)C(60) exhibit a similar mean-field temperature dependence. The characterization of triangle up and triangle up(T) for K(3)C(60) and Rb(3)C(60) provides essential constraints for theories evolving to describe superconductivity in the M(3)C(60) materials.     

中国细棘虾虎鱼属（鲈形目,虾虎鱼科）分类再研究

本文通过对中国细棘虾虎鱼属鱼类头部感觉管孔及感觉乳突排列规律的观察和比较，研究细棘虾虎鱼属种类分类，并对国内外鱼类学者对中国细棘虾虎鱼属鱼类的记录和分类进行了整理，列出了该属各种类的同物异名。将中国细棘虾虎鱼类分成两个亚属，共有１１种。     

Hg2+胁迫下细叶蜈蚣草对水体总磷去除效果的研究

采用室内培养分析测试方法,研究了在不同梯度浓度的Hg2 处理下,细叶蜈蚣草对水体总磷去除效果的动态变化情况。结果表明:对照组和Hg2 浓度为0.10 mg.L-1试验组在Hg2 处理的96 h内,细叶蜈蚣草对水体总磷去除率随着处理时间的延长而增加;0.50 mg.L-1和1.00 mg.L-1试验组在48 h内,细叶蜈蚣草对水体中总磷去除率一直上升,但96 h后对水体中总磷的去除率明显下降;Hg2 浓度大于1.50 mg.L-1的试验组中细叶蜈蚣草对水体中总磷去除率一直下降。同时,细叶蜈蚣草对水体总磷去除率的均值与Hg2 浓度亦均呈曲线关系,细叶蜈蚣草对水体总磷去除速率的均值与Hg2 浓度均呈曲线关系。     

Pattern of bombardment-produced radionuclides in rock 10017 and in lunar soil

A large number of radionuclides have been measured as a function of depth in lunar rock 10017 and in bulk fines. Data are reported on (10)Be, (22)Na, (26)Al, (36)Cl, (49)V, (53)mn, (54)Mn (55)Fe, (56)Co, (57)Co, and (59)Ni and on upper limits for (46)Sc, (48)V, (51)Cr, and (60)Co. The results for several nuclides show striking evidence of excess surface production attributable to solar flare particles. Data for short-lived species, (56)Co, (57)CO, (54)Mn, (55)Fe, and (22)Na, appear consistent with fluxes from known recent events. Long-lived species demonstrate the existence of solar flare protons and alphas at least for the last 10(5) to 10(6) years, at fluxes comparable to those now observerved.     

Carbon-free fullerenes: condensed and stuffed anionic examples in indium systems

Condensed, well-ordered analogs of the fullerenes occur in the hexagonal phases Na(96)In(97)Z(2) (Z = nickel, palladium, or platinum). Large cages of In(74) (D3h) and M(60) (= In(48)Na(12), D3d) share pentagonal faces to generate a double-hexagonal close-packed analog of NiAs. All these polyhedra are centered by partially disordered In(10)Z clusters within deltahedra of sodium atoms that cap all inner faces of the cages, namely, Z@In(10)@Na(39)@In(74) and Z@In(10)@Na(32)@Na(12)In(48) "onions" The highest filled bands in these compounds apparently involve localized electron pairs on surface features on In(74)-based layers. Structural and electronic relations between diamond and Naln (stuffed diamond structure) parallel those between certain fullerenes and Na(96)In(97)Z(2) and, presumably, other valence-driven intermetallic phases.     

相邻单元差值估计法的性质

对系统抽样的估计方差　　＾Ｖ１（－ｙｓｙ） ＝ （ １Ｍ－ １Ｎ） １Ｍ－ １ ∑Ｍｊ＝１（ Ｙｉｊ－ －Ｙｉ）２　　＾Ｖ２（－ｙｓｙ） ＝ （ １Ｍ－ １Ｎ） １２（ Ｍ－ １） ∑Ｍｊ＝１（ Ｙｉｊ－ Ｙｉ,ｊ＋ １）２我们有下列结果：（ｉ） 如果ρｋ ≠０ ,Ｖ（－ｙｓｙ） ＝ Ｖ（－ｙ） ,则Ｅ［ ＾Ｖ２（－ｙｓｙ）］ ≠Ｅ［ ＾Ｖ１（－ｙｓｙ）］ ＝ Ｖ（－ｙ） ;（ｉｉ） 如果ρｋ ＜ ０ ,Ｖ（－ｙｓｙ） ＜ Ｖ（－ｙ） ,则Ｅ［ ＾Ｖ２（－ｙｓｙ）］ ＞ Ｅ［ ＾Ｖ１（－ｙｓｙ）］＞ Ｖ（－ｙ） ;（ｉｉｉ） 如果ρｋ ＞ ０ ,Ｖ（－ｙｓｙ） ＞ Ｖ（－ｙ） ,则Ｅ［ ＾Ｖ２（－ｙｓｙ）］ ＜ Ｅ［＾Ｖ１（－ｙｓｙ）］ ＜ Ｖ（－ｙ） ．其中Ｖ（－ｙｓｙ） ＝ １Ｋ∑ｋｉ＝ １－Ｙｉ － －Ｙ ２ ,Ｖ（－ｙ） ＝ （ １Ｍ－ １Ｎ） １Ｎ－ １ ∑Ｋｉ＝ １ ∑Ｍｊ＝１Ｙｉｊ－ －Ｙ ２ρｋ ＝∑Ｋｉ＝ １ ∑Ｍ－１ｊ＝１（ Ｙｉｊ － －Ｙｉ）（ Ｙｉ,ｊ＋ １ － －Ｙｉ） ＋ １２ ∑Ｋｉ＝１（ Ｙｉ１ － －Ｙｉ）２ ＋ ∑Ｋｉ＝１（ ＹｉＭ－ －Ｙｉ）２∑Ｋｉ＝１ ∑Ｍｊ＝ １Ｙｉｊ － －Ｙｉ ２     

Metastable phases in polar stratospheric aerosols

Phase changes in stratospheric aerosols were studied by cooling a droplet of sulfuric acid (H(2)SO(4)) in the presence of nitric acid (HNO(3)) and water vapor. A sequence of solid phases was observed to form that followed Ostwald's rule for phase nucleation. For stratospheric partial pressures at temperatures between 193 and 195 kelvin, a metastable ternary H(2)SO(4)-HNO(3) hydrate, H(2)SO(4) . HNO(3) . 5H(2)O, formed in coexistence with binary H(2)SO(4) . kH(2)O hydrates (k = 2, 3, and 4) and then transformed to nitric acid dihydrate, HNO(3) . 2H(2)O, within a few hours. Metastable HNO(3) . 2H(2)O always formed before stable nitric acid trihydrate, HNO(3).3H(2)O, under stratospheric conditions and persisted for long periods. The formation of metastable phases provides a mechanism for differential particle growth and sedimentation of HNO(3) from the polar winter stratosphere.     

Epitaxial cuprate superconductor/ferroelectric heterostructures

Thin-film heterostructures of Bi(4)Ti(3)O(12)Bi(2)Sr(2)CuO(6+x), have been grown on single crystals of SrTiO(3), LaAlO(3), and MgAl(2)O(4) by pulsed laser deposition. X-ray diffraction studies show the presence of c-axis orientation only; Rutherford backscattering experiments show the composition to be close to the nominal stoichiometry. The films are ferroelectric and exhibit a symmetric hysteresis loop. The remanent polarization was 1.0 microcoulomb per square centimeter, and the coercive field was 2.0 x 10(5) volts per centimeter. Similar results were obtained with YBa(2)Cu(3)O(7-x) and Bi(2)Sr(2)CaCu(2)O(8+x), and single-crystal Bi(2)Sr(2)CuO(6+x)as the bottom electrodes. These films look promising for use as novel, lattice-matched, epitaxial ferroelectric film/electrode heterostructures in nonvolatile memory applications.     

Atmospheric lifetimes of long-lived halogenated species

The atmospheric lifetimes of the fluorinated gases CF(4), C(2)F(6), c-C(4)F(8), (CF(3))(2)c-C(4)F(6), C(5)F(12), C(6)F(14), C(2)F(5)Cl, C(2)F(4)C(12), CF(3)Cl, and SF(6) are of concern because of the effects that these long-lived compounds acting as greenhouse gases can have on global climate. The possible atmospheric loss processes of these gases were assessed by determining the rate coefficients for the reactions of these gases with O((1)D), H, and OH and the absorption cross sections at 121.6 nanometers in the laboratory and using these data as input to a two-dimensional atmospheric model. The lifetimes of all the studied perfluoro compounds are >2000 years, and those of CF(3)Cl, CF(3)CF(2)Cl, and CF(2)ClCF(2)Cl are >300 years. If released into the atmosphere, these molecules will accumulate and their effects will persist for centuries or millennia.     

湖北省不同地区水稻土对几种养分的吸附能力研究

对湖北省4个不同地区典型水稻土的磷(P)、钾(K)、硫(S)、硼(B)、锌(Zn)的吸附能力进行了研究。4种水稻土对P的吸收能力大小顺序为:洪湖市油-稻两熟区近代河流冲积物母质发育的水稻土(4#土)>襄樊市麦-稻两熟区Q3母质发育的水稻土(3#土)>荆门油-稻两熟区Q3母质发育的水稻土(2#土)>蕲春县油-稻-稻三熟制区花岗片麻岩母质发育的水稻土(1#土);对K的吸收能力大小顺序为:3#>4#>1#>2#;对S的吸收能力大小顺序为:3#>2#>4#>1#;对Zn的吸收能力大小顺序为:3#>4#>2#>1#;对B的吸收能力大小顺序为:3#>4#>1#>2#。田间养分管理策略应根据不同地区土壤对养分的吸附能力大小进行相应调整。     

鸭H9亚型禽流感油乳剂灭活疫苗的免疫原性

对从发病雏鸭体内分离到的H9亚型禽流感病毒NJ01株[A/Duck/Nan jing/01/1999(H9N2)]进行了免疫原性研究。以含有108.0ELD50和108.5ELD50的NJ01进行静脉注射攻击无H9亚型禽流感抗体的26日龄、44日龄和140日龄鸭,结果显示,对小于44日龄和大于44日龄鸭分别以108.0ELD50和108.5ELD50病毒含量的NJ01株静脉攻击,攻毒后1~2 d的喉拭子病毒分离率均为80%以上。将病毒含量为107.9ELD50的NJ01株油乳剂灭活苗,肌肉途径免疫8日龄和28日龄鸭,在免疫后的第7 d、14 d和21 d用含108.0ELD50和108.5ELD50的NJ01静脉注射攻击,攻毒后取1~2 d喉拭子进行病毒重分离,结果表明,免疫后7 d产生抗体,14 d产生坚强免疫力,21 d相对保护率达100%。     

Pyrrhotites: Stoichiometric Compounds with Composition Fen--1Sn (nge8)

A new type of natural pyrrhotite, orthorhombic 11C type (a = 6.892, b = 11.952, c = 5.744 x 11 angstroms), and the hexagonal 6C type (a = 6.89, c = 5.76 x 6 angstroms) are described. Their compositions are Fe(10)S(11) and Fe(11)S(12), respectively. Pyrrhotites stable in nature have essentially stoichiometric composition, Fe(n)-(l)S(n) (n>/=8), with the structures of n/2C type for n even and of nC type for n odd. The solid solutions between Fe(11)S(12) and Fe(10)S(11), and between Fe(10)S(11) and Fe(9)S(10) are considered metastable in nature.     

A-Axis--Oriented YBa2Cu3O7/PrBa2Cu3O7 Superlattices

A modulated structure has been fabricated from high transition temperature superconductors where the individual CuO(2) planes are composed of alternating superconducting and insulating strips. This structure is made by growing a-axis-oriented YBa(2)Cu(3)O(7)/PrBa(2)Cu(3)O(7) superlattices by 90 degrees off-axis sputtering on (100)SrTiO(3) and (100)LaAlO(3) substrates. Superlattice modulation is observed to a modulation wavelength of 24 angstroms (12 angstroms-YBa(2)Cu(3)O(7)/12 angstroms-PrBa(2)Cu(3)O(7)), both by x-ray diffraction and by cross-sectional transmission electron microscopy. Rutherford backscattering spectroscopy indicates a high degree of crystalline perfection with a channeling minimum yield of 3 percent. Quasi-one-dimensional conductivity should be obtainable in these structures.     

拟盘多毛孢属在云南的34个种

本文报道了在云南的拟盘多毛孢属（Ｐｅｓｔａｌｏｔｉｏｐｓｉｓ Ｓｔｅｙ．）真菌３４个种，其中新组合种９个：（１）生于中粒咖啡（Ｃｏｆｆｅａ ｒｏｂｕｓｔａ Ｌｉｎｄｅｎ．）叶上的蕃薯拟盘多毛孢菌〔Ｐ．ｂａｔａｔａｅ（ＥＩＩ．＆ Ｅｖ．）Ｇ．Ｃ．Ｚｈａｏ ＆ Ｌｉ．ｃｏｍｂ．ｎｏｖ．〕；（２）生于蕃石榴（Ｐｓｉｄｉｕｍ ｇｕａｊａｖａ Ｌ．）叶上的木防已拟盘多孢菌（Ｐ．ｃｏｃｕｌｉ （Ｇｕｂａ）Ｇ．     

16种（品种）寒地型草坪草抗旱性及评定方法初探

本文对１６种（品种）寒地型草坪草抗旱性及六种抗旱性评定方法进行了研究．根据综合评定的结果，得到它们的抗旱顺序依次为紫羊茅＞狐茅＞猎狗高羊茅，瓦巴斯草地早熟禾＞ＢＯ－１号（剪股颖）＞眼镜蛇匍匐剪股颖、玛瑞草地早熟禾＞细叶早熟禾＞肯塔基草地早熟禾＞菲尔金草地早熟禾＞赛博草地早熟禾、荷兰草地早熟禾＞德比黑麦草＞多年生黑麦草＞爱胄草地早熟禾＞午夜草地早熟禾，综合评定的结果与实践观察结果基本一致，效果较为理想．     

Erratum

In the 26 December issue [Science 128, 1614 (1958)], the solutions to the problem "A door opening was 3 feet 9 inches higher than it was wide. Which one of the following best expresses the area of the door opening, in square inches, after the opening has been heightened 2 inches and narrowed 3 inches?" were erroneously given as A) lc + (x/w) B) l + (w/cx) C) l + (cw/x) D) (l + cw)/x E) (l + cx)/w The possible solutions should have been A) x(2) + 44x - 141 B) x(2) + 47x + 141 C) x(x + 45 ) + 66 D) x(2) + 45 + 72 E) (x + 45) (x - 3).     

The Postspinel Phases in the Mg2SiO4-Fe2SiO4 System

Samples of olivine (Fo(0)Fa(100), Fo(60)Fa(40), Fo(80)Fa(20), and Fo(100)Fa(0)) and of spinel (Fo(50)Fa(50), Fo(2)Fa(100), where Fo is forsterite and Fa is fayalite) were subjected to pressures up to 250 kilobars in a diamond anvil press and were heated in situ up to ~ 1700 degrees C by an infrared beam from a continuous-wave YAG (yttrium-aluminum-garnet) laser. The brightness temperature was determined from the intensity of incandescence of the sample by means of an optical pyrometer. X-ray diffraction patterns of the samples, obtained after quenching and unloading, show conclusively that these compositions disproportionate to (Mg, Fe)O and SiO(s) (stishovite) under these conditions.