长江口海域悬浮物的分布时空变化特征

本文以１９８６年冬季和夏季两个航次调查资料，研究了长江口吸其毗邻海域的枯丰水期的数百个海不悬浮物样品的成分和分布。悬浮颗粒物浓度变化范围，河口区，夏季为１３４．０－１８９．０ｍｇ’ｄｍ＾３，冬季为７１．６－２９９．０ｍｇ／ｄｍ＾３，而海区，冬季为６．９－１２．５display status     

我国各地膨润土化学组成及其矿床矿样间差异性

考察了我国各地膨润土的化学组成以及各类型矿床矿样间的差异性 ,并对膨润土各化学组分间的相关性进行了分析。研究表明 ,硅和铝相对含量的变化是控制膨润土化学成分最主要的因素 ,富镁环境有利于蒙脱石形成 ,钛含量在供试样品间差异较小     

中国河道外用水变化趋势分析

以1980、1993、1997三年的全国性河道外用水调查统计数据为依据 ,结合有关社经资料 ,全面系统分析了全国及各流域片的用水总量、用水组成、用水指标的变化趋势。从1980年至1997年 ,全国总用水量由4437亿m3 增加到5566亿m3,平均每年增加66 4亿m3,年均递增率为1 34 % ;用水组成有明显变化 ,农业用水比例由83 4 %下降到70 4 % ,工业用水比例由10 3 %上升到20 2% ,生活用水比例由6 3 %上升到9 4 % ;人均综合用水量变化不大 ,稳定在450m3左右 ;综合用水效率不断提高 ,万元GDP(1980年不变价)用水量由9820m3 下降到2410m3。     

The enantiomeric composition of monoterpene hydrocarbons in the defensive secretions ofNasutitermes termites (Isoptera): Inter- and intraspecific variations

Summary Frontal gland secretions of termite soldiers of the speciesNasutitermes costalis, N. ephratae, N. nigriceps, N. rippertii, andN. hubbardii were analyzed. The chiral compositions of the monoterpene hydrocarbons were investigated by means of two-dimensional gas chromatography. Two of them, 3-carene and-pinene were present in the form of (–)-enantiomers of high purity in the majority of the samples. The other monoterpenes,-pinene, camphene, sabinene, limonene, and-phellandrene, exhibited a great variation in the enantiopurity between different species.-Pinene and limonene varied significantly even between different colonies within the species.N. costalis was the only species with an invariable composition of the secretion, independent of the locality or origin.     

上海市城市垃圾处理现状

说明上海市城市垃圾的产生、组成和收集运输情况，介绍常用垃圾处理方法和上海市城市垃圾卫生填埋技术，描述厌氧塘－兼性塘－曝气塘接湿地土地处理的上海市城市垃圾渗沥水处理方法，并展望上海未来城市垃圾处理的远景。     

Atmospheric mineral particles collected at Qira in the Taklamakan Desert, China

Aerosol particles were collected in the situation of the widespread dust suspension on 21 February 1991 at Qira in the southern edge of the Taklamakan Desert, western China. The collected particles were examined by a transmission electron microscope equipped with an energy-dispersive X-ray (EDX) analyzer in order to obtain the size and elemental composition of individual mineral particles.On the basis of EDX analyses for 386 particles, mineral particles were present in high number fractions (>99%) of particles in the radius range of 0.1–4 μm. Particles mainly composed of silicates comprised 76% of mineral particles. “Ca-rich” particles were detected in 7% of all the particles. Ca in the particles would be present not only as CaCO₃ but also as an internal mixture of CaCO₃ and CaSO₄. Particles containing halite (NaCl) were detected in number proportions of about 10% and were mainly present in the radius range of 0.5 μm. Some halite particles would be modified by chemical reactions with sulfuric acid.     

Shift in ectomycorrhizal community composition in Scots pine (Pinus sylvestris L.) seedling roots as a response to nickel deposition and removal of lichen cover

Scots pine seedlings were exposed to wet-deposited nickel (Ni) and removal of lichen cover in a dry heath Scots pine forest. Ni deposition affected the colonization of roots by indigenous ectomycorrhizal fungi in contrasting ways in intact and skimmed quadrats. Highest frequencies of tubercle morphotypes of ectomycorrhiza were found in quadrats exposed to 100 mg m⁻² year⁻¹ Ni in lichen covered treatment, while in skimmed quadrats these peaked after the treatment with 10 mg Ni m⁻² year⁻¹. Removal of the lichen layer increased the value of diversity index (H′) of ectomycorrhizal fungal community, probably due to the increase in the evenness of the morphotype distribution. Lichen removal seemed also to improve the condition of the short roots, as the frequencies of poor and senescent short roots were decreased by the removal.     

Degradation of benomyl, picloram, and dicamba in a conical apparatus by zero-valent iron powder

Reduction of some pesticides (benomyl, picloram, and dicamba) was studied in an aerobic batch conical pilot system to investigate the disappearance of these pesticides on contact with iron powder (20 g/l, 325-mesh). Aqueous buffered solutions of the compounds were added to the system followed by zero-valent iron powder (ZVIP), and the decline in the pesticide concentrations was monitored over time. HPLC analyses show a complete disappearance of picloram (1.20 mg/l) after 20 min of reaction. Benomyl (1.00 mg/l) and dicamba (1.25 mg/l) disappear after 25 and 40 min, respectively. The t₅₀ values ranged from 3 to 5.5 min, and were about slightly less than the t_1/2 values reported when the log of the relative HPLC peak area was plotted versus time, where the relative peak area was calculated by dividing the measured peak area by the initial peak area. Pathways for the degradation of the studied pesticides by ZVIP are proposed.     

盾构隧道内大客车人员下车试验及数值模拟研究

为研究盾构隧道火灾时大客车人员构成比例及满载系数对下车时间影响,采用现场试验及Pathfinder数值模拟,分析不同人员构成比例及满载系数下大客车人员下车过程。结果表明:不考虑人员疏散反应时间情况,大客车下车时间为54～68 s,大客车平均下车时间为60.68 s,每位人员平均下车时间为1.22 s;老人下车时间最长,成年女士下车时间最短,成年男士与儿童下车时间基本相等。当老人比例在30%~80%范围变化时,下车时间随老人比例增大显著增加;成年女士比例对大客车下车时间影响较小;大客车人员下车时间与满载系数相关,随满载系数增加而增加,并趋于正比例函数关系。     

Role of small mammals in natural and anthropogenic landscapes of the right-bank region of Saratov oblast

Small mammal communities inhabiting natural and anthropogenically transformed areas of the right-bank region of Saratov oblast are fairly similar in species composition. They are represented by wide-spread, common species that, against the background of a low population density of typical steppe species, make a major contribution to the community. The highest ecological tolerance is characteristic of the striped field mouse Apodemus agrarius, which is widespread in the study region and dominates in the majority of natural biotopes and in agrocenoses; the common vole Microtus arvalis is scarce in agrocenoses.