广州市区人工湖泊PFU原生动物群落群集过程及其对水质差异的指示作用

应用PFU法(GB／T12990-91)对广州市区主要湖泊——流花湖、荔湾湖和麓湖的原生动物群落与水质进行研究．结果表明：用PFU法所测定和计算的原生动物群集的种类数、植鞭虫指数、群集参数(SeqG、T90%)、群落多样性指数d和群落污染值(CPV)等都能较好地指示3个人工湖泊水质的差异，水质由优到劣的排列顺序为麓湖＞荔湾湖＞流花湖．流花湖、荔湾湖和麓湖目前虽仍处于富营养状态，但清污截流等对城市湖泊污染的综合治理措施可以减少湖泊外部营养物负荷及沉积物内负荷，降低水体的营养盐含量，有助于原生动物群落的恢复．图3表3参16     

Floristic composition and vegetation ecology of the Malindi bay coastal dune field, Kenya

A short outline is given of the floristic composition, structure and distribution of coastal dune vegetation found at Malindi Bay, Kenya. The area was studied by air photo interpretation and field sampling to determine the relationship of plants to aeolian features. TWINSPAN classification was used to distinguish geomorphological units on the basis of their species composition. In this paper, an inventory and first quantitative analysis of vegetation distribution is presented. We identified 174 plant species from 62 families in the sand dunes and several plant communities are distinguished based on the species content and the connection with morphological units.Papilionaceae with 18 species andPoaceae with 17 species were the most represented families. A distinct zonal distribution of the plant communities was found. The most important plant species are the pioneer vegetation consisting ofHalopyrum mucronatum, Ipomoea pescaprae andScaevola plumieri. The woody shrub species which have colonized the established primary dunes and hummock dunes areCordia somaliensis, Pluchea discoridis, Tephrosia purpurea (dunensis). Succulent herbs were identified in the dune slacks and salt marsh that are moist and damp environments.     

海洋细菌B3B产河豚毒素特性的鉴定及其发酵培养基优化

从我国渤海红鳍东方豚(Fugu rubripes)的卵巢中分离到了一株海洋细菌B3B,对其发酵产物进行了分离和精制,通过小鼠试验、高效液相色谱试验及质谱分析,认定其发酵产物中含有河豚毒素(tetrodotoxin,TTX).采用均匀设计回归分析及优化系统对其培养基组分做了优化,获得了较理想的发酵培养基,使TTX的产量提高了128.7%.图2表2参21     

超材料复合吸波体的设计与研制

目的研制一种比传统吸波材料雷达波衰减更强、合格频带更宽的新型吸波材料。方法设计超材料谐振单元图案及其组合排列方式,采用丝网印刷工艺在介质基板上制作超材料吸波体,与传统吸波材料复合形成超材料复合吸波体。通过对比分析不同介质基板、谐振单元图案及组合方式、导电炭黑含量对复合吸波体的性能影响规律。结果超材料复合吸波体能实现比传统吸波材料,在12～17 GHz峰值反射率最大降低-20 dB;在2～18 GHz反射率低于-20 dB的带宽拓展17.7%。结论新研制的超材料复合吸波体实现了峰值衰减更强与合格带宽拓宽的研究目的,对未来吸波材料的发展极具研究价值与方向指引。     

以控制资源消耗量为突破口做好环境保护规划

提出了稳态、非稳态社会经济系统在环境方面的基本关系式.着重说明了资源消耗量是源头上的"因",而环境质量是最终的"果".提出了以控制资源消耗量为重点,进一步完善末端治理,提高环境自净能力,标本兼治的环境保护工作思路.介绍了编制环保规划要掌握的2个基本公式.强调了单位(以104元计)GDP环境负荷及其年下降率的重要性.穿越"环境高山",应成为制定规划的目标.按计划管理模式,编制环境保护规划,在我国可能是完全必要的.      

14C‐dimethoate residues in olive oil during oil processing

Abstract

An olive tree was treated twice in the field with ¹⁴C‐dimethoate (237.7 (μCi, 2.4 g) and ¹⁴C residues were determined in the olive fruits at harvest. The fruits were crushed and pressed to extract the crude oil, then refined by neutralization, bleaching and deodorization. The crude oil contained 14.1% of the total ¹⁴C in the olive fruits. Neutralization resulted in a reduction of ¹⁴C by about 50% of the total ¹⁴C residues in oil. Bleaching and deodorization processes further reduced the ¹⁴C residues and the refined oil contained 31.6% (which corresponds to 4.4% of ^I4C residues of the total ¹⁴C in olive fruits) of the total ¹⁴C in the crude oil. Industrially extracted crude oil was fortified with ¹⁴C‐dimethoate at 1.8 mg kg^‐1 (0.02 μCi) level and subjected to the same refining process. A sharp decrease in the amount of ¹⁴C was observed by neutralization and the amount of ¹⁴C remaining in the refined oil was about 7.3% of the total ^l4C in the crude fortified oil. The data suggest that the ¹⁴C residues in the aged and the fortified oil amples were not of the same nature. The terminal ¹⁴C residue in the refined oil obtained from the field experiment did not contain dimethoate and/or its oxon.     

基于迭代退火算法的高压变频器功率单元频繁故障诊断方法研究*

现有的变压器故障诊断方法较为复杂且计算冗余度较高,在高压变频器的功率单元频繁发生故障时难以高效地检测故障。为此,提出基于迭代退火算法的高压变频器功率单元频繁故障诊断方法。采用小波包分解方法提取高压变频器功率单元的电压信号特征熵,将该特征熵输入到支持向量机模型。使用迭代退火算法优化支持向量机的训练参数,并输出诊断结果。研究结果表明:该方法提取的高压变频器单元故障的平均冗余度最低至3.2%,平均诊断时间为15.1 ms,可实现高压变频器功率单元频繁故障的高效诊断。     

动态瓦斯地质预测算法研究与可视化应用

为实现煤矿瓦斯地质动态精准预测与可视化,基于煤层埋深、厚度、倾角、地质构造等多种因素,通过将相似的地质模块定义为同一微单元,在此基础上将反距离权重插值算法和递归邻域搜索策略与数据优化处理算法相结合,应用于瓦斯地质动态预测可视化系统开发。研究结果表明:根据递归邻域搜索算法模型开发的多级瓦斯地质图动态分析系统利用瓦斯地质基础数据可对矿井瓦斯含量、压力、涌出量等瓦斯赋存参数进行实时分析和计算,动态绘制散点图、等值线和区域预测图,使瓦斯区域预测图过渡更加平缓,显著提高预测的精准性及整体的显示效果,同时其制图耗时也无明显增加,可为高瓦斯矿井安全生产提供决策依据。     

丁二烯装置基于风险的检验技术应用

采用RBI技术对丁二烯装置进行风险评估,经分析装置存在的主要损伤机理有碱应力腐蚀开裂、有机酸腐蚀、冷却水腐蚀、冲刷腐蚀和丁二烯自聚等,装置的风险由失效后果主导,失效可能性较高的评估.单元集中在脱重冷凝系统和薄壁小直径管道。根据基于风险的检验策略对装置实施检验,检验过程中发现装置存在脱重冷凝系统设备应力腐蚀开裂、一萃塔系统换热器点蚀、接管角焊缝开裂和压力管道腐蚀減薄等主要问题,检验检测结果与风险评估过程中识别的损伤机理和薄弱环节保持一致。     

炉盖排风罩在精炼炉除尘系统中的应用

介绍了炉盖排风罩在涟钢一炼钢厂 2× 30t钢包精炼炉除尘系统中的应用 ,并将其与传统的炉内捕集式炉盖进行分析比较 ,说明其优越性和推广价值。由于该项技术的使用 ,涟钢一炼钢厂精炼炉除尘系统从根本上解决了环保与生产之间的矛盾 ,运行结果表明 ,各项技术指标均可达到国家标准