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811.
ZHANG XiaoLii HE Xini LIU DingZheni YAO XiuLini ZHANG YiZhuo ZHANG EnQuan ZHANG JinGuo JIANG GuoHua ZHAO ChangQi 《科学通报(英文版)》2013,58(18):2220-2229
The effects of individual removal by zoo managers on behavior and fecal glucocorticoid changes in snub-nosed monkeys(Rhinopithecus roxellana) were investigated at Beijing Zoo.The results showed that the effect of the removal of three subordinate individuals(DD,male,4 years;XZZ,male,3 years and LL,female,3 years) from a group varied across the remaining group members that may be related to individual’s social status,gender and age.The dominant male was impacted less than subordinate individuals in both the frequency and time duration for the four main behavioral categories.The frequency of stereotypic behavior significantly decreased in the dominant female after the removal of three animals(Z= 2.862,P=0.003).Fluctuations were found in both the behavioral frequency and time duration in other remaining individuals.These findings suggest that small,socially stable groups were somewhat resilient to changes in member composition.Moreover,the cortisol level did not change significantly in the remaining members.An alternative method of hormone assay using fecal samples for vulnerable animals was presented,and that may be useful for monitoring wild golden monkeys and other endangered species of animal. 相似文献
812.
高速铁路是复杂的巨系统。京津城际铁路是我国首条工程实践、运营实践的高速铁路,在攻克系统设计与系统集成、轨道高平顺与高稳定、高速列车安全与舒适、运行(营)控制可靠与高效四大方面科技难题和关键技术取得了重大创新成果;历时3年建造,开通运营验证,整体达到世界领先水平;该成果对推进我国铁路网又好又快地建设具有指导性、示范性的重大作用。 相似文献
813.
The abundant entities and entity-attribute relations in medical websites are important data resources for medical research. However, the medical websites are usually characterized of storing entity and attribute values in different pages. To extract those data records efficiently, we propose an automatic extraction system which is related to entity and attribute relations (attributes and values) of separate storage. Our system includes following modules: (1) rich-information interactive annotation page rendering; (2) separate storage attribute relations annotating; (3) annotated relations for pattern generating and data records extracting. This paper presents the relations about the attributes which are stored in many pages by effective annotation, then generates rules for data records extraction. The experiments show that the system can not only complete attribute relations of separate storage extraction, but also be compatible with regular relation extraction, while maintaining high accuracy. 相似文献
814.
Hydrothermal reactions of oxalic acid(H2ox) and 2-sulfobenzoic acid(H2L) with lanthanide oxide or hydroxide yielded five lanthanide oxalatosulfocarboxylates.They have a general formula [Ln2L2(ox)(H2O)6]n[Ln = La(1),Nd(2),Eu(3),Gd(4),Tb(5)].Their structures were characterized by single crystal X-ray diffraction,powder X-ray diffraction(PXRD),infrared(IR) spectroscopy,elemental analysis(EA),and thermogravimetric analysis(TGA).1-5 are isostructural coordination polymers and feature one-dimensional(1D) chains,which are extended into 3D supramolecular frameworks through inter-chain hydrogen bonds between coordinated H2O donors and oxygen acceptors from carboxylate,sulfonate and oxalate groups.In addition,the solid-state photoluminescence properties of the Nd(2),Eu(3) and Tb(5) derivatives have been measured at room temperature.The Eu and Tb-containing coordination polymers(CPs) exhibit intense red and green luminescence emissions,respectively,with lifetimes in the order of millisecond. 相似文献
815.
Bi2Se3 thin films were electrochemically deposited on Ti and indium tin oxide-coated glass substrates, respectively, at room temperature,
using Bi(NO3)3·5H2O and SeO2 as starting materials in diluted HNO3 solution. A conventional three-electrode cell was used with a platinum sheet as a counter electrode, and a saturated calomel
electrode was used as a reference electrode. The films were annealed in argon atmosphere. The influence of cold isostatic
pressing before annealing on the microstructure and thermoelectric properties of the films was investigated. X-ray diffraction
analysis indicates that the film grown on the indium tin oxide-coated glass substrate is pure rhombohedral Bi2Se3, and the film grown on the Ti substrate consists of both rhombohedral and orthorhombic Bi2Se3. 相似文献
816.
We investigated the dynamic properties of a two-section composite chain of beads under vertical vibration.By analyzing the chain’s motion,including phase-shift,mean dilation,center-of-mass displacement,and energy,we found that with different bead arrangements,the chain behaved in different ways.We believe that interaction existing at the interface between bead sections provides the underlying cause.This interaction causes different energy in different arrangements,which leads to different dynamic characteristics. 相似文献
817.
Sheng-jun Li Yuan Lin Wei-wei Tan Jing-bo Zhang Xiao-wen Zhou Jin-mao Chen Zeng Chen 《矿物冶金与材料学报》2010,17(1):92-97
The ZnO-modified TiO2 electrode was prepared by adding Zn(CH3COO)2·2H2O to the TiO2 colloid during the sol-gel production process, and was used in dye-sensitized solar cells (DSCs). The open circuit voltage
(V
OC) and fill factor (ff) of the cells were improved significantly. The performances of the ZnO-modified TiO2 electrode such as dark current, transient photocurrent, impedance, absorption spectra, and flat band potential (V
fb) were investigated. It is found that the interface charge recombination impedance increases and V
fb shifts about 200 mV toward the cathodic potential. The effect mechanism of ZnO modification on the performance of DSCs may
be that ZnO occupies the surface states of the TiO2 film. 相似文献
818.
何建朝 《重庆三峡学院学报》2010,26(2):34-39
《庄子》"谬悠之说,荒唐之言,无端崖之辞,时恣纵而不傥,不以见之也"的独特风格的形成原因,是一种以"虚构"和"幻想"组成的"虚幻"思维。通过深入探析这一思维的结构内核,我们可以发现其对当下的本土奇幻小说的影响。 相似文献
819.
TiO2-based nanosheets (TiNSs), TiO2-based nanotubes (TiNTs) were prepared by hydrothermal processing, and polyurethane foams with TiO2 nanopowders (P25), TiNSs and TiNTs were synthesized by free-rising foaming method. The Fourier-transform infrared (FT-IR) spectra show that the addition of titanium dioxide does not affect the chemical structure of polyurethane foam. However, microscope observations show that PU/TiNSs composite foams have more uniform cells and the average aperture smaller than that of pure poly-urethane foams. According to the results of thermal analysis, the PU/TiNSs composite foams have better thermal stability, the temperature of decompostion occurring with a maximum weight loss rate is about 30 ℃ higher than that of pure PU foams. The decompostion temperatures are 167 ℃ and 148 ℃ for the PU/P25 composite foams and the PU/TiNTs composite foams respectively, which are lower than that of pure PU foams. Moreover, with the addition of the fillers, the sound absorption property also has changed; the addition of TiNSs improved the sound absorbing property efficiently. The better thermal stability and sound absorption of PU/TiNSs composite foams are mainly due to the uniform cells diffuse and smaller aperture. 相似文献
820.
关于水利工程钢筋混凝土施工技术的探讨 总被引:1,自引:0,他引:1
水工混凝土建筑物因所受水荷载及温度变化等条件的不利影响,建成后往往带病运行,运行后又有一个老化过程,因此需要精心地检查、维护和修理才能保证其安全运行。否则,一定期限后就会发生严重事故,许多预防老化病害的措施,在规划设计和施工阶段就应认真考虑并实施。笔者就钢筋混凝土施工中的技术工作进行了探讨。 相似文献