甘肃白龙江流域苔藓植物种类组成和分布类型的初步研究

白龙江位于甘肃南部,属长江水系,是嘉陵江的一级支流,流域面积31800 km2.对该流域进行调查研究后,报道苔藓植物34科,89属,172种,其中甘肃省新记录科4个,新记录属17个,新记录种70个.并初步分析了白龙江流域苔藓植物的特点.     

High repetition rate passively mode-locked erbium-doped fiber laser

We report a passively mode-locked high repetition rate erbium-doped femtosecond fiber laser via nonlinear polarization rotation, with a fundamental repetition rate of 101.94 MHz. The output power is 34 mW when pumped by a single mode fiber coupled laser diode at 370 mW. The spectral width is 25 nm, corresponding to a transform limited pulse width of 105 fs.     

Occurrence of sulfonamide antibiotics in sewage treatment plants

The occurrence of sulfonamide antibiotics （SAs） was investigated in the six sewage treatment plants （STPs） of Beijing, China. Of the 13 objective antibiotics, suIfamethoxazole, suIfapyrldine, suIfamerazine, sulfadiazine and suIfamethizol were detected in the influents with the average concentrations of 1.2 ± 0.45, 0.29 ± 0.25, 0.048 ± 0.012, 0.35 ± 0.52 and 0.33 ± 0.21 μg·L^-1, respectively, and those in the effluents were 1.4 ± 0.74, 0.22 ± 0.19, 0.021 ± 0.008, 0.22 ± 0.21and 0.01± 0 μg·L^-1, respectively. SuIfamethoxazole was the predominant compound detected, and was found in all wastewater samples with the other two compounds sulfapyridine and suIfamerazine. It should be noted that suIfadiazine was first reported in wastewatera, and the concentration levels of all detected compounds except for suIfamethizol （detected once in the effluent samples） in the influents were observed to be similar to those in the effluents. From the dsts in this study, it can be found that suIfamethoxazole, suIfapyridine, suIfamerazine and suIfadiazine could be partly removed in anoxic and aerobic treatment unit and vice versa in anaerobic process, which led to their low or even negative removal rates in the effluents. The increase on the concentrations of suIfamethoxazole and suIfapyridine in the effluents was found probably due to the biotransformation of their acetylated forms in anaerobic treatment unit. In addition, it was observed that the biodegradation of suIfamethoxazole and suIfapyridine could partly occur during the anoxic and aerobic process, while suIfamerazine was partly eliminated in the anaerobic and anoxic units.     

Millennial temperature reconstruction based on tree-ring widths of Qilian juniper from Wulan, Qinghai Province, China

The climate of the past 1000 years is an important context for evaluating the recent climate warming. However, there are few 1000-year-long climate reconstructions with annual resolution in the Qinghal-Tibet Plateau. In this paper, a dendroclimatic analysis was conducted for the radial growth of Qilian juniper from the upper forest limit in Wulan, Qinghai Province. The results of correlation analysis between the tree-ring widths and the climate variables indicate that the growth of junipers at the upper forest limit is mainly limited by low temperatures of September, November and February of the pregrowth season, and July of the current growth season. There is no significant correlation between the tree-ring widths and precipitation. A mean temperature from the previous year＇s September to the current year＇s April was reconstructed for the Wulan area since A.D. 1000. The reconstruction can explain 40.8% of the instrumental variance in the calibration period （1856-2002）. The reconstruction shows that the 20th century is the warmest 100 years, and the 1990s is the warmest decade during the past 1000 years, while the coldest 100 years and decade occur at 1600-1699 and 1642-1651, respectively. The variations are verified well by the temperature reconstruction of the middle Qilian Mountain （QL） and the total organic carbon （TOC） in the Qinghai Lake sediments. The comparison of our reconstruction with the annual temperature reconstruction of extra-tropical Northern Hemisphere suggests that the climate of Wulan during the Medieval Warm Period is of obvious regional specialty, but there was a good response to the climate of hemispheric scales during the recent 400 years.     

功能对等理论指导下的颜色习语翻译

颜色习语形象生动,蕴含丰富的比喻意义与文化内涵,承载着独特的风俗习惯与民族特色,其翻译也因浓厚的文化特色而无法实现完全对等。"功能对等"翻译理论作为奈达翻译理论的核心,对颜色习语的翻译有重要的指导意义。     

湖南废次烟叶中茄尼醇的提取工艺研究

采用有机溶剂浸取法提取湖南废次烟叶中的茄尼醇,单因素实验获得了其较佳工艺条件为：正己烷为溶剂,浸取温度为30℃,浸取2个小时,重复浸取2次.在该较佳工艺条件下进行实验,提取率为1.25%,得率为90%.     

一类特殊的三色有向图的本原指数

一个三色有向图D是本原的,当且仅当存在非负整数h,k,l,且h＋k＋l〉0,使得D中的每一对顶点（i,j）都存在从i到j的（h,k,l）-途径,并称h＋k＋l的最小值为D的本原指数.文章研究一类特殊的三色有向图,其未着色图恰含一个n-圈、一个3-圈和一个4-圈,我们研究了该图的本原性并给出了在一种本原条件下的三色有向图的本原指数.     

取向估计方法研究进展

取向是一个区分多维信号和一维信号的基本特征,取向估计在图像处理和机器视觉中具有重要作用。总结了取向估计方法的原理、现有方法以及进一步的研究方向等等。     

技术解放作用与奴役性评析

分析了技术发展对人类生存和发展带来的巨大积极作用和诸多威胁,提出必须树立以人为本,人与自然协调发展的技术观,以促进技术的健康发展。     

有效利用专利文献提高企业技术创新能力

文章从专利文献的特点入手,介绍了专利文献在企业技术创新中的作用,并通过对我国、我省企业利用专利信息现状的分析,分别从政府、企业和信息咨询服务机构三个层面,对加快专利信息的传播、开发和利用,提高企业创新能力提出了相应的措施建议.