论中国种子植物特有属在台湾的分布

通过对台湾产的12个中国种子植物特有属即青钱柳属Cyclocarya,通脱木属Tetrapanax,华参属Sinopanax,八角莲属Dysosma,棱果花属Barthea,棱果茜属Hayataella,银脉爵床属Kudoacanthus,异叶苣苔属Whytockia,毛药花属Bostrychanthera,泡果荠属Hilliella,悬竹属Ampelocalamus.井岗寒竹属Gelidocalamus等的地理分布分析,发现台湾产的中国种子植物特有属具有衍生性质,属于次生的成分.     

外力作用下管道内表面缺陷处裂纹扩展研究

为提高油气管道安全风险评估的准确性,以含内表面缺陷管道为研究对象,利用ABAQUS软件线弹性及弹塑性分析不同尺寸缺陷对裂纹萌生特征的影响;采用扩展有限元法,建立管道3点弯曲模型与全尺寸静载物理试验,并非线性拟合裂纹扩展尺寸,研究内表面缺陷处裂纹扩展情况.研究结果表明:内表面缺陷中心处极易萌生裂纹,随着缺陷尺寸的增大,裂...     

Canopy Seed Banks as Time Capsules of Biodiversity in Pasture-Remnant Tree Crowns

Abstract: Tropical pastures present multiple barriers to tree regeneration and restoration. Relict trees serve as “regeneration foci” because they ameliorate the soil microclimate and serve as safe spots for dispersers. Here, we describe another mechanism by which remnant trees may facilitate pasture regeneration: the presence of seed banks in the canopy soil that accumulates from decomposing epiphytes within the crowns of mature remnant trees in tropical cloud forest pastures. We compared seed banks of canopy soils (histosols derived from fallen leaves, fruits, flower, and twigs of host trees and epiphytes, dead bryophytes, bark, detritus, dead animals, and microorganisms, and dust that accumulate on trunks and the upper surfaces of large branches) in pastures, canopy soils in primary forest trees, and soil on the forest floor in Monteverde, Costa Rica. There were 5211 epiphytic and terrestrial plant seeds in the three habitats. All habitats were dominated by seeds in a relatively small number of plant families, most of which were primarily woody, animal pollinated, and animal dispersed. The density of seeds on the forest floor was greater than seed density in either pasture‐canopy or forest‐canopy soils; the latter two did not differ. Eight species in 44 families and 61 genera from all of the habitats were tallied. There were 37 species in the pasture‐canopy soil, 33 in the forest‐canopy soil, and 57 on the forest floor. Eleven species were common to all habitats. The mean species richness in the pasture canopy was significantly higher than the forest canopy (F =83.38; p < 0.02). Nonmetric multidimensional scaling ordination revealed that the communities were distinct. Greenhouse experiments verified that many of these seeds were viable, with 29 taxa germinating (23 taxa in pruned mats [mimic of exposed conditions] and 16 taxa in control mats [intact conditions]) within 2 months of observation. Nearly half the species that germinated were characteristic of primary forests (primary forest samples, 19%; pasture samples, 29%). This supports the idea that canopy seed banks of pasture trees can function as time capsules by providing propagules that are removed in both space and time from the primary forest. Their presence may enhance the ability of pastures to regenerate more quickly, reinforcing the importance of trees in agricultural settings.     

Large-scale risk assessment of polycyclic aromatic hydrocarbons in shoreline sediments from Saudi Arabia: Environmental legacy after twelve years of the Gulf war oil spill

A large-scale assessment of polycyclic aromatic hydrocarbons (PAHs) from the 1991 Gulf War oil spill was performed for 2002-2003 sediment samples (n = 1679) collected from habitats along the shoreline of Saudi Arabia. Benthic sediment toxicity was characterized using the Equilibrium Partitioning Sediment Benchmark Toxic Unit approach for 43 PAHs (ESBTU_FCV,43). Samples were assigned to risk categories according to ESBTU_FCV,43 values: no-risk (≤1), low (>1-≤2), low-medium (>2-≤3), medium (>3-≤5) and high-risk (>5). Sixty seven percent of samples had ESBTU_FCV,43 > 1 indicating potential adverse ecological effects. Sediments from the 0-30 cm layer from tidal flats, and the >30-<60 cm layer from heavily oiled halophytes and mangroves had high frequency of high-risk samples. No-risk samples were characterized by chrysene enrichment and depletion of lighter molecular weight PAHs, while high-risk samples showed little oil weathering and PAH patterns similar to 1993 samples. North of Safaniya sediments were not likely to pose adverse ecological effects contrary to sediments south of Tanaqib. Landscape and geomorphology has played a role on the distribution and persistence in sediments of oil from the Gulf War.     

Rain‐washing of foliar deposits of Dimilin®WP‐25 formulated in four different carrier liquids

Abstract

Dimilin^® WP‐25, a wettable powder formulation of diflubenzuron (DFB) [1‐(4‐chlorophenyl)‐3‐(2,6‐difluorobenzoyl) urea], was formulated in four different carrier liquids, viz., water; a light petroleum paraffinic oil, ID 585; a heavy paraffinic oil, Sunspray^® 7N; and a 1:2 mixture of a light petroleum aromatic solvent (Cyclosol^® 63) and canola oil; to provide four end‐use mixtures, Dim‐W, Dim‐585, Dim‐7N and Dim‐Cy‐C respectively, each containing 28 g of DFB per litre. Balsam fir branch tips clipped from greenhouse‐grown seedlings, and sugar maple branch tips clipped from field‐grown young trees, were exposed to uniform‐sized droplets (ranging in diameters from 135 to 190 μm) of the four end‐use mixtures which were atomized using a monodispersed droplet generator. Droplets were collected on the fir and maple branch tips and the initial residue per g fresh weight of foliage was determined by high‐performance liquid chromatography (HPLC). The branch tips were exposed to cumulative rainfall of 3, 6 and 10 mm at an intensity of 5 mm/h and at time intervals of 1, 12, 36 and 72 h after DFB treatment, to test the influence of ‘ageing’ of foliar residues on rainfastness. Foliar samples were collected for residue determination just before the onset of rainfall, and at 0.5 h post‐rain. DFB was quantified by the HPLC method. In the case of fir foliage, the Dim‐W formulation was the most susceptible to rain‐washing and the rainfastness did not increase with the ageing period of foliar deposits. In contrast, the three oil‐based mixtures showed greater rainfastness depending upon the carrier liquid and the ageing period. Rainfastness decreased in the order of Dim‐Cy‐C > Dim‐7N > Dim‐585 > Dim‐W. In contrast, the data on maple foliage indicated that the ageing of deposits increased the rainfastness of all the 4 end‐use mixtures. Dim‐585 was the most susceptible to rain washing, and rainfastness decreased in the order of Dim‐W > Dim‐Cy‐C > Dim‐7N > Dim‐585.     

植物油燃料研究概述

本文介绍了植物油作燃料的研究历史以及试验研究状况，表明植物油作为柴油的替代品是最易实现的方案。但植物油燃料还需进一步试验研究才能使其实用化，其技术储备具有深远的现实意义。本文还通过对燃料油植物栽培问题的探讨，认为“农林复合经营”是生产植物燃料油的重要途径。     

Synthesis of cellulose-fatty acid esters for use as biodegradable plastics

Long-chain fatty acid carbohydrate esters (FACE) were synthesized by the acid chloride-pyridine reaction to different degrees of substitution (DS). The hydrolyzed soybean oil was used as the source of unsaturated fatty acids. High molecular weight FACE polymers are insoluble in common solvents, such as benzene, toluene, THF, etc., and are highly water resistant. However, FACE polymers of hydrolyzed cellulose (MW 180 kD) are soluble/swellable in toluene and can be cast into tough, flexible films. FACE polymer properties of tensile strength and clasticity vary with degree of substitution and polymer size.Paper presented at the Bio/Environmentally Degradable Polymer Society—Third National Meeting, June 6–8, 1994, Boston, Massachusetts.     

切实做好全厂停工检修中的环保工作

为确保炼油厂设备安全而稳定地运行，各生产装置都要定期进行停工检修，在此期间排放的污染物对环境将产生一定的影响。停工检修中的环保工作包括实施环保措施；加强环境管理；并且将2000m~3隔油池由一间式变为两间式，提高污水处理率和达标率。     

催化裂化废水萃取脱酚预处理研究

选用焦化粗柴油为萃取剂,对催化裂化含酚废水进行脱酚预处理,结果表明,最佳萃取条件为：ｐＨ７．０－８．５,温度１５－４０℃,油水体系比１．７－２．１,理论萃取级数４－７级。在上述条件下,出水酚质量浓度为５０ｍｇ／Ｌ。萃取后的粗柴油用于炼油厂加氢精制装置。     

Utilization of red mud as catalyst in conversion of waste oil and waste plastics to fuel

The aim of this study was to investigate the possibilities of using a by-product (red mud) from alumina production as a catalyst for recovery of waste. The conversion of waste mineral oil (WMO) and waste mineral oil/municipal waste plastic (WMO/MWP) blends over red mud (RM), a commercial hydrocracking catalyst (silica–alumina), and a commercial hydrotreating catalyst (Ni–Mo/alumina) to fuel has been studied. The effect of the catalyst and the temperature on the product distribution (gas, liquid, and wax) and the properties of liquid products were investigated. In the case of hydrotreatment of WMO, the liquids obtained over RM at both 400° and 425°C had larger amounts of low-boiling hydrocarbons than that of thermal or catalytic treatment with hydrotreating catalyst. Gas chromatography and nuclear magnetic resonance analysis of the liquid products showed that RM had hydrogenation and cracking activity in hydrotreatment of WMO. In coprocessing of WMO with municipal waste plastics, temperature had an important effect as well as the amount of MWP in the blend and the catalyst type. The hydrocracking at 400°C produced no liquid product. In hydrocracking at 425°C, the product distribution varied with catalyst type and MWP amount. The commercial hydrocracking catalyst had more cracking ability in the conversion of WMO/MWP to liquid and gas fuel than RM. In the case of hydrocracking over RM, the largest amount of liquid having satisfactory quality was obtained only from the blend containing 20% MWP.