(RbxK1-x)3C60 Superconductors: Formation of a Continuous Series of Solid Solutions

By means of an approach that employs alkali-metal alloys, bulk single-phase (RbxK1-x)(3)C(6O) superconductors have been prepared for all x between 0 and 1. For x = 1 it is shown that the maximum superconducting fraction, which approaches 100% in sintered pellets, occurs at a Rb to C(60) ratio of 3:1. More importantly, single-phase superconductors are formed at all intermediate values of x, and it is shown that the transition temperature (T(c)) increases linearly with x in this series of materials. The formation of a continuous range of solid solutions demonstrates that the rubidium- and potassium-doped C(60) superconducting phases must be isostructural, and furthermore, suggests that the linear increase in T(c) with x results from a chemical pressure effect.     

毛百合×有斑百合种间杂种的核型研究

利用染色体常规压片方法,对毛百合、有斑百合及其3个杂种后代进行了核型分析.结果表明:毛百合、有斑百合和3个杂种染色体均为2n=2x=24.毛百合核型公式为2n=6m(2SAT)+4sm(2SAT)+14st,有斑百合核型公式为2n=2m+8sm+12st+2t,杂种F1-1核型公式为2n=4m+2am+18st,F1-2核型公式为2n=2m+8sm(2SAT)+14st,F1-3核型公式为2n=2m+8sm+14st.F1-1、F1-2和母本的核型类型都是3B型,而F1-3与父本的核型类型都是3A型.在染色体长度比、平均臂比及不对称系数等指标上,杂种大部分都趋于父母本的中间值.杂种染色体形态具有父母本双亲的特点,可以鉴定为真杂种.     

草莓属植物染色体核型分析

[目的]分析二倍体野生种草莓的核型,为探讨草莓的起源、进化及遗传育种研究提供依据。[方法]对草莓属（Fragaria）植物4个二倍体种森林草莓（F.vescaL.）、纤细草莓（F.gracilis A.Los.）、黄毛草莓（F.nilgerrensis Schidl）和五叶草莓（F.pentaphylla A.Los.）进行了核型分析。[结果]纤细草莓的核型为2n=2x=14=10m＋2sm＋2m＊,属1B类型;黄毛草莓为2n=2x=14=14m,属1A类型;五叶草莓为2n=2x=14=12m＋2sm,属1A类型;森林草莓为2n=2x=14=14m,属1A类型。[结论]草莓二倍体及品种核型对称性为：黄毛草莓〉森林草莓〉五叶草莓〉纤细草莓,供试草莓种的新缘进化顺序可能为黄毛草莓、森林草莓、五叶草莓、纤细草莓。     

奥地利黑麦染色体核型和C-分带带型

以奥地利黑麦(S eca le cerea le L.)为试验材料,通过G iem sa C-分带对其进行了细胞学鉴定、染色体核型与C-带分析。结果表明,奥地利黑麦体细胞染色体为14条,花粉母细胞减数分裂中期Ⅰ染色体形成7个二价体,其核型公式为2n=2x=14=10m+2sm+2m(SAT)。通过C-分带将奥地利黑麦1R~7R的7条染色体区分开来,其C-带带型公式为2n=14=2C+I+T+2C+T+4I+T+2C+I+T++2T+2ST。奥地利黑麦除2R和4R长臂近端部约1/4处有带且7R无中间带外,其余带型与黑麦标准C-分带带型基本一致。     

一类等距结点上的双周期整插值问题

给定结点组xk=kπ/σ(σ>0,k∈Z),对于正整数m1相似文献   

A Molecular Ferromagnet with a Curie Temperature of 6.2 Kelvin: [Mn(C5(CH3)5)2]+[TCNQ]-

The study of magnetic phase transitions in insulating molecular solids provides new insights into mechanisms of magnetic coupling in the solid state and into critical phenomena associated with these transitions. Only a few such materials are known to display cooperative magnetic properties. The use of high-spin molecular components would enhance intermolecular spin-spin interactions and thus a series of chargetransfer (CT) salts have been synthesized that utilize the spin S = 1 molecular cation, [Mn(C(5)(CH(3))(5))(2)](+) (decamethylmanganocenium). The structure and cooperative magnetic behavior of [Mn(C(5)(CH(3))(5))(2)](+)[TCNQ(-) (decamethylmanganocenium 7,7,8,8-tetracyano-p-quinodimethanide) are reported. This salt is a bulk molecular ferromagnet with the highest critical (Curie) temperature (T(c) = 6.2 K) and coercive field (3.6 x 10(3) gauss), yet reported for such a material.     

毛百合×布鲁拉诺杂交后代核型研究

利用染色体常规压片法,对毛百合(2n=2x=24)×布鲁拉诺(2n=4x=48)杂交后代核型进行了研究。结果表明：杂交后代MB70-48染色体数为2n=2x=24,而MB70-30、MB72-6、MB71-5染色体数为2n=3x=36。毛百合核型公式为2n=2x=24=2m+4sm+12st+6t,布鲁拉诺核型公式为2...     

渥丹百合不同居群核型研究

采用染色体常规压片的方法,对渥丹百合(Lilium.concolorSalisb.)4个居群进行了染色体核型分析,结果表明,有斑百合BH27(L.concolorvar.buschianumBaker.)和有斑百合BH41(L.concolorvar.buschianumBaker.)核型分别为2n=2x=4m(2SAT) 4st 16t(2SAT)和2n=2x=4m(4SAT) 12st 8t(4SAT),黄花渥丹BH20(L.concolorvar.concolorf.coridionKitag.)核型为2n=2x=4m(4SAT) 4st 16t(4SAT),大花百合BH50(L.concolorvar.megalanthumWangetTang)核型为2n=2x=4m(4SAT) 6st(2SAT) 14t(4SAT);其核型分类都属于3B型,但结构变异明显,主要表现在染色体相对长度、臂比、次缢痕数目及分布。     

The spin excitation spectrum in superconducting YBa(2)Cu(3)O(6.85)

A comprehensive inelastic neutron scattering study of magnetic excitations in the near optimally doped high-temperature superconductor YBa(2)Cu(3)O(6.85) is presented. The spin correlations in the normal state are commensurate with the crystal lattice, and the intensity is peaked around the wave vector characterizing the antiferromagnetic state of the insulating precursor, YBa(2)Cu(3)O(6). Profound modifications of the spin excitation spectrum appear abruptly below the superconducting transition temperature T(c), where a commensurate resonant mode and a set of weaker incommensurate peaks develop. The data are consistent with models that are based on an underlying two-dimensional Fermi surface, predicting a continuous, downward dispersion relation connecting the resonant mode and the incommensurate excitations. The magnetic incommensurability in the YBa(2)Cu(3)O(6+)(x) system is thus not simply related to that of another high-temperature superconductor, La(2-)(x)Sr(x)CuO(4), where incommensurate peaks persist well above T(c). The temperature-dependent incommensurability is difficult to reconcile with interpretations based on charge stripe formation in YBa(2)Cu(3)O(6+x) near optimum doping.     

Analyses of Numerical Responses and Main Life Parameters for Determining the Suppression of Amblyseius cucumeris on Panonychus citri

In this paper, the numeral response and main parameters of experimental population life table were analyzed for determiningthe suppressing ability of Amblyseius cucumeris on Panonychus citri. The result showed that: (1) Under 21-31 ℃ and 1-9 prey densities/leaf fragment condition, the prey consumptions ofA. cucumeris increased with the temperature or prey density; (2) In 1:3 predator-prey ratio treatment, the suppression ofP. citri (Ro=34.0053; T=19.4369; t=3.8204) was rather weak, it was enhanced as the ratio over 5:30, and the populations ofP. citri in these treatments can be fully controlled within 4-5 days; (3) Under 25±1℃, 80-85% RH and 15L: 9D illumination conditions, the net reproductive rate, mean generation duration and the time for population double increase ofP. citri (Ro=34.0053; T=19.4369; t=3.8204) were higher than those ofA. cucumeris (Ro=21.8750; T=16.8943; t=3.7954). While the intrinsic rate of increase and finite rate of increase of the former (rm=0.1814; λ= 1.1989) were lower than those of the latter (rm=0.1826; λ= 1.2004). These results indicated that A. cucumeris is a desirable bio-control agent to suppress P. citri at lower population stage in citrus orchard.     

吉林省3种萱草的核型研究

本文对吉林省３种萱草进行了细胞学观察，其染色体数目和核型报道如下：北京黄花菜Ｈｅｍｅｒｏｃａｌｌｉｓｌｉｌｉｏ－ａｓｐｈｏｄｅｌｕｓＬ．２ｎ＝２２＝１０ｍ＋６ｓｍ＋４ｓｔ＋２Ｔ；小黄菜菜Ｈ．ｍｉｎｏｒＬ．２ｎ＝２２＝４ｍ＝１４ｓｍ＋２ｓｔ（２ＳＡＴ）＋２Ｔ ；重瓣萱草Ｈ．ｆｕｌｖａＬ．ｖａｒ．ｋｗａｎｓｏＲｅｇｅｌ为三倍体，２ｎ（３ｘ）＝３３＝１８ｍ＋９ｓｍ＋３ｓｔ＋３Ｔ，３个种的核型均属于２Ｂ型     

Observation of d(x2-y2)-like superconducting gap in an electron-doped high-temperature superconductor

High-resolution angle-resolved photoemission spectroscopy of the electron-doped high-temperature superconductor Nd(2-x)Ce(x)CuO4 (x = 0.15, transition temperature T(c) = 22 K) has found the quasiparticle signature as well as the anisotropic d(x2-y2)-like superconducting gap. The spectral line shape at the superconducting state shows a strong anisotropic nature of the many-body interaction. The result suggests that the electron-hole symmetry is present in the high-temperature superconductors.     

以色列野生二粒小麦和光稃野燕麦杂交亲本与后代核型分析

 对以色列野生二粒小麦（母本）和光稃野燕麦（父本）远缘杂交亲本与后代的核型及进化关系进行了分析。结果表明：母本的染色体长度比为1626,核型公式为2n=4x=28=18m（2SAT）+10sm（2SAT）,核型为1A。父本的染色体长度比为2526,核型公式为2n=6x=42=20m（2SAT）+22sm（4SAT）,核型类型为2B。以色列野生二粒小麦和光稃野燕麦杂交后代0878株系的染色体数目为42,染色体长度比为1.802,核型公式为2n=6x=42=22m（2SAT）+20sm（2SAT）,核型为2A。 0878-1株系的染色体数目为42,染色体长度比为2.057,核型公式为2n=6x=42=38m+4sm（4SAT）,核型为2B。由于光稃野燕麦遗传物质渗入到该杂交后代,获得了进化程度高于其母本的普通小麦型小麦新种质。     

Superconductivity at 40 K in the Oxygen-Defect Perovskites La2-xSrxCuO4-y

Structural, magnetic, and electronic properties of compounds in the series La2-xSrx CuO4-y for 0.05 相似文献   

药用植物茴香的细胞学研究

采用压片法,对生长在武汉地区的药用植物茴香(Foeniculum vulgareMiller)进行细胞学研究。结果表明:茴香的绝大多数花粉母细胞减数分裂过程中染色体的行为正常,终变期形成11个二价体,为染色体计数的最佳时期;茴香的染色体数目为2n=2x=22,核型公式为K(2n)=22=20m 2sm,其染色体相对长度组成为2n=2s 8M1 10M2 2L,属于“1A”对称型核型。     

HPLC法检测复合维生素片中叶酸和维生素B_(12)的含量

[目的]建立应用高效液相法测定复合维生素片中叶酸和维生素B12含量的方法。[方法]色谱柱用菲罗门lunaC18(4.6×250 mm,5μm),流动相为甲醇-0.028 mol/L磷酸氢二钠水溶液(用磷酸调pH到3.5)(21∶79),流速1.0 ml/min,检测波长为361 nm,进样量为20μl,柱温为25℃。[结果]维生素B12在6.65～66.50 ng范围内呈现良好的线性关系,回归方程是y=0.495 1x+1.342 8(R2=0.999 4,n=6),平均回收率为96.83%,RSD为0.82%(n=6)。叶酸在80～800 ng范围内呈现良好的线性关系,回归方程是y=0.021 1 x+0.661 1(R2=0.998 8,n=6),平均回收率为95.56%,RSD为1.54%(n=6)。[结论]高效液相色谱法灵敏度高,操作简便,重现性好,结果准确,可以用于复合维生素片中叶酸和维生素B12的含量测定。     

〔(亚洲棉×比克氏棉)F_1双二倍体×海岛棉〕F_1茸毛性状研究

亚洲棉茎叶茸毛少而短,比克氏棉茎叶茸毛多而长,山西农业大学棉花育种组创育的〔（亚×比）〕Ｆ１双二倍体（２ｎ＝４ｘ＝５２,Ａ２Ａ２Ｇ１Ｇ１）,茎、叶茸毛多而长,表明比克氏棉这一多毛抗虫性状被表达出来,本文用（亚×比）Ｆ１双二倍体与茸毛稀少的栽培四倍体海岛棉杂交,其多而密的茸毛性状能继续在杂种Ｆ１中得到表达。     

羊柴等四种沙生灌木的核型研究

本文对羊柴等四种沙生饲用灌木的染色体数目及核型进行研究。结果表明：羊柴核型为２ｎ＝２ｘ＝１６＝１６ｍ（２ＳＡＴ）；花棒核型为２ｎ＝２ｘ＝１６＝１６ｍ（２ＳＡＴ）；柠条为２ｎ＝＝２ｘ＝１６＝１６ｍ；红皮沙拐枣为２ｎ＝２ｘ＝３８＝２Ｍ＋４ｍ（２ＳＡＴ）＋８ｓｍ＋２ｓｔ＋２２ＴＴ。     

贝母属4种核型的报道

对四川产的４种贝母进行了核型研究，米贝母ＦｒｉｔｉｌｌａｒｉａｄａｖｉｄｉｉＦｒａｎｃｈ，核型公式为２ｎ＝２ｘ＝２４＝２ｍ＋２ｓｍ＋１０ｓｔ＋１０ｔ，染色体相对长度系数Ｉ．Ｒ．Ｌ＝２Ｌ十２Ｍ２十７Ｍ１＋２ｓ核型为２Ｂ型，瓦布贝母ＦｒｉｔｉｌｌａｒｉａｗａｂｕｅｎｓｉｓＳ．Ｙ．ＴａｎｇｅｔＳ．Ｃ．Ｙｕｅｈ，核型公式为２ｎ＝２ｘ＝２４＝２ｍ＋２ｓｍ（ＳＡＴ）＋２０ｔ，染色体相对长度系数Ｉ．Ｒ．Ｌ＝４Ｌ＋６Ｍ２＋１２Ｍ１＋２Ｓ，核型为２Ｂ型；浓度贝母ＦｒｉｔｉｌｌａｒｉａｍｅｌｌｅａＳ．Ｙ．ＴａｎｇｅｔＳ．Ｃ．Ｙｕｅｈ，核型公式为２ｎ＝２ｘ＝２４＝２ｍ＋２ｓｍ＋２０ｔ，染色体相对长度系数Ｉ·Ｒ·Ｌ＝４Ｌ＋８Ｍ２＋１０Ｍ１＋２Ｓ，核型为３Ａ型；槽鳞贝母ＦｒｉｔｉｌｌａｒｉａｕｎｉｂｒａｃｔｅａｔａＨｓｉａｏｅｔＫ．Ｃｓｉａｖａｒ．ｓｕｌｃｉｓｑｕａｍｏｓａ（Ｓ．Ｙ．ＴａｎｇｅｔＳ．Ｃ．Ｙｕｅｈ）ＨｓｉａｏｅｔＳ．Ｃ．Ｙｕ，核型公式为２ｎ＝２Ｘ＝２４＝２Ｘ（ＳＡＴ）＋２ｓｍ＋１０ｔ，染色体相对长度系数Ｉ．Ｒ．Ｌ＝４Ｌ＋４Ｍ２＋１４Ｍ１＋２Ｓ，核型为３Ｂ型。该４种贝母核型较一致，但各种之间在次缢痕、随体、Ｂ染色体的数目?     

彩棉三个品种的核型对比分析

采用常规压片法对滨彩2号(浅棕色)、99-55(深棕色)和滨绿1号(绿色)的染色体数目和核型进行了研究,得出结论:滨彩2号的染色体数目为2n=4x=52,核型公式为:k(2n)=4x=52=22m 18sm(2SAT) 12st,属于"2B"类型.染色体相对长度组成为2n=4x=52=10L 16M2 14M1 12S;99-55染色体数目为2n=4x=52,核型公式为:k(2n)=4x=52=26m(2SAT) 22sm 4st,属于"2B"类型.染色体相对长度组成为2n=4x=52=12L 10M2 22M1 8S;滨绿1号的染色体数目为2n=4x=52,核型公式为:k(2n)=4x=52=40m 12sm(2SAT),属于"1B"类型.染色体相对长度组成为2n=4x=52=8L 16M2 18M1 10s.