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Thirty-four palaemonid species from the northern area of South China Sea are reported in the present paper, including two new species, Paranchistus lini, new species, and Periclimenes chacei, new species, and eight other species are reported for the first time from South China Sea: Leander tenuicornis (Say, 1818), Leandrites stenopus Holthuis, 1950, Palaemon debilis Dana, 1852, Urocaridella antonbrurnii (Bruce, 1967), Kemponia platycheles (Holthuis, 1952), Paraclimenes franklini (Bruce, 1990b), Paranchistus spondylis Suzuki, 1971, Periclimenes hirsutus Bruce, 1971.

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对青海禾本科一新种——昂赛披碱草(Elymus angsaiensis S.L.LuetY.H.Wu)进行了形态描述和图解。该种与黑紫披碱草(E.atralus(Nevski)Hand.-Mazz)相近,但本种的叶鞘顶端两侧具披针形叶耳;穗状花序较疏松;小穗具小穗柄长约1mm,且具微毛;颖片窄披针形,长4~5mm;花药黄色或黄绿色,长约1.5mm,可以区别。

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采用两两互作实验并以尿标记来确定共居至成年的2雄性根田鼠同胞在行为竞争上的差异,之后在行为选择箱中分别观察它们对来自熟悉和陌生同性个体的新鲜尿气味的行为反应,以确定气味识别差异.结果表明:①雄性根田鼠两两互作时,尿标记的多少可以作为判断其社会等级的标准;②从属鼠对熟悉气味存在明显偏好,其对熟悉气味的访问时间、接近频次和自我修饰频次都显著高于陌生气味;③优势鼠则优先访问陌生气味,其对陌生气味的访问时间、嗅舔频次、嗅舔时间、自我修饰及反标记均显著高于熟悉气味;④对于陌生气味,优势鼠和从属鼠之间存在明显不同的行为反应模式.本实验结果提示,雄性根田鼠对同性尿气味识别的差异以及对陌生气味的行为反应,可能暗含着其领域防卫的信息.

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利用连续提取法(SEDEX) 详细调查了太湖五里湖表层沉积物中不同形态磷的组成和分布特征。结果显示:其中磷的含量较高,受人为污染输入的影响较大,并且已经有了一定的释放。总磷的变化范围为2105~4105 mg/ g ,平均约为2180 mg/ g。总磷主要由无机磷组成(70 %~90 %) ,大多数无机磷为CDB 溶液提取的铁结合态磷(75 %~85 %) 。CDB 溶液的n ( Fe) / n ( P) 都较小(210~513) ,说明CDB 溶液提取的铁主要是以无定形态存在的,并且铁与磷酸盐之间的吸附可能已经达到了平衡状态。除底部个别样品以外,多数样品n (Corg) / n (Norg) 较小(818~1016) ,所有样品的n (Corg) / n ( Porg) 都较大(135~320) ,表明沉积物在早期成岩作用过程中,湖泊内源自生有机质降解时有机磷优先释放。无机磷,特别是铁结合态磷,在氧化还原条件变化的情况下,能够通过沉积物—水体界面被再次释放到水体中去,这可能对湖泊的水体质量和营养状况有一定的影响。

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应用超临界CO2 萃取技术从印楝种子中萃取印楝素,研究了萃取温度、压力和夹带剂对印楝素萃取效果的影响。当萃取温度为35 ℃、压力为15 MPa、甲醇用量为CO2 体积的3 %时,可将印楝种子中90 %以上的印楝素A 萃取出来,所得产品印楝素A 的质量分数为2013 %。

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采用低硼高杂质离子样品硼同位素分析方法测定了黄土、古土壤样品中酸溶相硼含量及硼同位素组成。洛川黄土S0-S2剖面酸溶相硼含量变化范围为(0.8-2.7)×10-6,其δ11B值在-1.8~+18.6‰之间变化,多集中在0~+10‰之间。古土壤层的硼含量及δ11B值高于黄土层,尤以S1层表现最显著。引起剖面上酸溶相硼含量及δ11B值变化的主要原因是化学风化作用和粘土吸附作用强度的变化,气候条件变化所引起的风化作用强度的变化可能是酸溶相硼含量及δ11B值发生变化的原因。

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On the basis of the geological field investigations and isotope geochronological studies the Sm-Nd isochron age (513 Ma?0 Ma), Rb-Sr isochron age (511 Ma? Ma) and K-Ar age (312-317 Ma) of the Dapingzhang spilite-keratophyre formation in Yunnan Province are presented. From these geochronological data it is evidenced that this suite of volcanic rocks was formed in the Cambrian and the parent magma was derived from a depleted mantle, which was influenced by crustal contamination and/or seawater hydrothermal

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采用X射线衍射(XRD)和分析透射电镜(TEM)测试技术,对贵州产70、120、210kN和日本产120、210kN瓷绝缘子产品中长石物相组成、结构特征进行了测定和观察.结果表明,上述类型的瓷绝缘子产品均含有不等量的钾长石和斜长石,随瓷绝缘子等级增高、结晶质含量越高其长石含量降低,证实了高等级瓷绝缘子中存在长石,并分析其可能的形成机理.

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The variation of surface compositions on amorphous Ni80.4W1.5P18.1 alloy by O-2 oxidation and H-2 reduction treatments have been studied by XPS, UPS and ISS. It shows that addition of tungsten in the amorphous Ni-P alloy leads to dramatic changes of the relating component distributions in the surface layers before and after these treatments. Oxidation of a Ni80.4W1.5P18.1 amorphous alloy in 1 bar of oxygen at 513 K caused a significant segregation of nickel in different oxide states at the surface. The subsequent reduction of the oxidized surface with I bar hydrogen at 553 K resulted in only a small portion of Ni and P being reduced into elemental states, while most of them was found to combine to form a kind of nickel phosphate compound. On the other hand, under the same conditions, the oxidation and reduction of a Ni80P20 alloy gave rise to metallic Ni and elemental P as the predominate species on the alloy surface. The addition of W in the amorphous alloy might act as nuclei for a favorable formation of the phosphate structure which was proposed to be an active species for hydrogen-relating catalytic reactions. (C) 1999 Elsevier Science B.V. All rights reserved.

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From the organizational behavior point, this study initially explored how factors of educational changes influenced on teachers. This study adapted the questionnaire made up by Consortium for Cross-Culture Research in Education (CCCRE), by cooperating with other countries, interviewed 513 teachers in nine countries. The main results are as follows: 1. Factors of educational changes include: domain, origin, objective, teachers' role, and timetable. Comparative results show: More similarities than differences tend to be presented in five factors. The detail results are: in domain, it mainly involves teaching change and learning outcomes change; in origin, the educational change most teachers participated was initialed by government; in role, teachers more act as the implementer; in timetable, gradual development is the chief characteristic. 2. The domain of change, origin and teachers' role has a significant impact on the quality of worklife of teachers, but timetable of change has not. The further study about the influence of educational origin on the quality of worklife of teachers shows: Changes of teachers' time -using, professional development were significantly impacted by the origin of education, and there is a significant difference in the change of time-using among nine countries. 3. Change on students, change on teachers' relationship are two important factors to impact the teachers' evaluation about educational change. But the teachers' evaluation, teaching age and the change on relationship are valid factors to predicate teachers participate in next educational change. 4. Compared with the educational change of other eight countries, the change in school system management and the change in learning outcomes are more carried on in China. There is no significance about other factors between China and overall nine countries. In China, the educational change has a more positive impact on teachers' time-using and professional development, but professional development is also a important factor to impact teachers' evaluation on change; however there is a negative relationship between the Chinese teachers' evaluation and the teachers' participation in next change.